NikonGear'23
Gear Talk => Camera Talk => Topic started by: Michael Erlewine on April 25, 2017, 14:02:16
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Right now, with the X1D, I am learning to take photographs, as in: the process. I am not quite there with the camera enough to capture my ‘impressions,” at least not yet. And it’s not just the learning curve I’m talking about either, but the entire process, in particular getting the focus and the aperture just right. This will take some time.
The process involved in using the X1D is more involved than the simplistic camera it is made out to be. Since I tend to use LiveView, outside and in sunlight, this requires some kind of optical viewfinder to block the sunlight and offer some magnification. I started out with the Zacuto Z-Finder, hanging from a lanyard around my neck. However, the Z-Finder is so robust that its heaviness proved distracting. So, I switched to one of the ELVID viewfinders that, while not as good as the Zacuto, are so very light that I even forget I’m wearing it. Still, it is sharp enough and magnifies adequately to work just fine. I don’t need the extra clarity offered by the Z-Finder, at least not with the LiveView screen on the X1D. I can see to focus via the magnification “star” button.
Meanwhile, I am still very put off by the fact that LiveView switches off automatically after 15 seconds. This is not helpful when setting up a shot with the X1D, so I have no idea what they were thinking. However, I have been assured that this LiveView problem is fixed in the next firmware update, so I can wait for that. I am getting too old to always be the sacrificial lamb at the altar of technology, even (or especially!) with a Hasselblad.
I will leave it to others to comment on using the X1D for sports or walk-around shots. I may get to that, but so far that has not happened. I do have to keep remembering to have the timer on, since often (but not always) it turns itself off when I turn the camera off. Perhaps someone could tell me how to set it and have it on permanently. Since there is no hard-wired remote cord, I am stuck with the timer or using Phocus on my iPhone, which is just one more stone around my neck to carry around.
I am happy with the color on the X1D although I do find myself looking to NIK’s “Color Efex Pro 4” to tweak the removal of color casts from time to time. As mentioned earlier, at this stage in my learning curve I am just taking photos with the X1D, not actually creating them yet in my style, although I am getting close.
I am more or less happy with the lenses and understand that they may be working to improve the focus shift of the 90mm lens. I do everything with manual focus, and that is working OK. As for stacking, no problem, but I have not attempted large stacks, only what I call short stacks of maybe 3-4 layers. Like all cameras, this one takes some study, coupled with learning to use a medium-format lens, such as it is.
There is no doubt that I move more slowly with the X1D compared to the Nikon D810, and it is not just because it is a new camera to learn. In large, being more careful and attentive to process is good for me, and the X1D demands this if I want good results. So, I am into it.
Things I would like: Aside from leaving LiveView on, I would like a wired or IF remote and not have to haul around (and be careful of) my iPhone with Phocus software to be a remote. No thanks!
I would like a separate button to return to LiveView other than trying to guess how much pressure to place on the shutter release without accidently taking an unwanted photo. That is a pain.
And I would like my 30mm lens to arrive, which they took the entire money for but have yet to produce. As for batteries, when I asked the fellow at B&H when my two extra batteries would come (this about a month ago), his answer was July, which I couldn’t believe. So, at GREAT expense, I found and bought the first two batteries to come up on Ebay, giving me three. That is enough for now... I hope.
As for repairs, I have not needed any, but I did call the Hasselblad Bron center in New Jersey and they explained that they try to repair things there; otherwise they send them overseas. So, I’m crossing my fingers.
And finally, I am waiting (like many) for the release of the 120mm Macro lens in June, since that is the lens I need for most of my work. I don’t do much macro anymore, but I do a lot of close up. That’s the state of the situation with the X1D for me.
A shot with the 90mm, lightly stacked. Not there yet, but working on it.
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Thank you for your observations. It is good to hear how you are getting on with it.
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Dear Michael
Thanks for continuing to give this invaluable first hand feedback on the X1D. Have you considered using H lenses using the XH adapter? Used H lenses are advertised at reasonable prices compared to new (eg B&H)
thanks
woody
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Dear Michael
Thanks for continuing to give this invaluable first hand feedback on the X1D. Have you considered using H lenses using the XH adapter? Used H lenses are advertised at reasonable prices compared to new (eg B&H)
thanks
woody
I have tried stuff like that and it just gets too big and clunky for my taste and the lenses often are not that great IMO.
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I have had my new Hasselblad X1D on the back burner for a couple of weeks, while waiting for a lens that I can do close-up work with. Instead, I have been doing close-up photography with my trusty Nikon D810 with and without the Cambo Actus. And I have been getting some great shots.
But I thought to just do a little X1D shooting, getting as close-in as I can with the 90mm and 45mm lenses that I have for that camera. So, I took a few stacked photos, making just short stacks of several images.
I was a little shocked to see the IQ of the X1D images, compared to the Nikkor lenses I have been using, like the Otus 55mm APO, the El Nikkor 105mm APO, and some others. There is a sense of space and light with the X1D that is pretty much missing from the Nikon images. Hmmmm.
There is a darkness and almost a viscosity to the Nikon images that is not there in those from the X1D. I almost feel naked when I look at the X1D images, or it’s like walking from a darker room out into the sunlight, so much space and transparency.
Of course, I don’t have any close-up lenses for the X1D, as mentioned, not yet, so if I did that would “close me in” to good degree and make things more equal. But, right now, I am impressed anew with the quality of the Hasselblad images.
And I also see the challenge of MF in terms of focusing and putting images together. Because the lenses are not fast, there is little depth-of-field; everything is mostly in focus. And I guess the larger photosites gather more light. So, the X1D is definitely for a different kind of photography than the more impressionistic photos I tend to take. I will continue to do those on the Nikon D810 and on the X1D, who knows? I’m going to have to learn that as I go.
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Meanwhile, back in the jungle (so to speak), I continue to vet the Hasselblad X1D. I’m long past the time-period I could return it, so it’s mine. Right now, the X1D is limited by the lenses available to me. I’m not about to buy the adapter to mount the old and too-bulky Hasselblad lenses, not to mention the T/S adapter as well. I had bought one to try out (120mm Macro), but it was HUGE, so I sold it back on Ebay.
IMO, the X1D sensor is a better sensor than my D810, but the lenses (90mm and 45mm) are not better lenses than, say, the Zeiss Otus 55mm and their APO kin. So, who wins out? Well, so far (in my use) the Otus lenses win out and that means the D810 is still the camera I am most-often reaching for. This could change if I had the XCD 30mm and especially when the XCD 120mm Macro finally shows up, if that lens is up to speed.
I find the Hasselblad X1D easier and easier to use. As for any focusing issues, I find myself not using the focus points at all, but just double-tapping the point on the LiveView screen I want and magnifying that. For me, that works great and I can drag the magnified point around with my finger to where I want it. It is so easy. However, I do find myself automatically trying to tap on the LCD screen of the D810, which tells me that I like this approach.
Right out of the chute, the color of the X1D seems better than what I can get out of my D810. The images of both cameras have to be color-tweaked, but to my eyes the X1D color is much closer (or at least somewhat closer) than that from the Nikon D810.
I’m not a techspert, but lately I have been doing my own form of testing, comparing the X1D and the D810, using many hundreds of tests. Looking closely at the results at many f/stops, I find the quality of the Otus lenses beat out anything I can get in terms of fine detail from the X1D 90mm lens, although I am sure most folks could care less to even look. Yet, if they did, that is what they would find.
I am so used to the X1D by now that (aside from the LiveView turning itself off after 15 seconds, which should be soon fixed) I find the X1D very easy to use. In fact, anyone could use it, including more technical folks like me. Haptic-ally I like this camera. And since I finally got a bunch of extra batteries, that helped a lot. Do keep in mind that I am only using the X1D in manual focus mode. I never use autofocus or almost never.
I have yet to do any family walk-around shots or things like that. Right now, I am trying to duplicate my standard type of work, and have not come up with a match. It is getting obvious that the X1D has qualities of its own and means a shift to seeing what this camera can do outside of what I’m used to.
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Michael,
A Nikon D810 sensor presents 8.62 square centimeters of image sensor to the light from the lens while a Hasselblad X1D presents 14.52 square centimeters to the light. [If the intensity per square centimeter is constant, shutter speed and aperture then the Hasselblad X1D collects almost 1.7x the light (1.68x) compared to the Nikon and...] If other things are equal such as electronic noise the Hasselblad should give better color fidelity and higher dynamic range. Is this what you are finding?
The big question mark is are the lenses available to take advantage of potentially higher image quality?
Dave Hartman
What about adapting the Nikkor AM series APO lenses to the 1XD since the ones you own are I believe mounted in shutters? Is this practical?
[ As usual my dyslexia kicked in and I didn't type what I was thinking hence the edit above. Sorry for the mistake. ]
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The X1D collects "more" light and has a larger area to distribute that amount over. Thus the light intensity (light/unit area) is exactly the same. Intensity determines exposure not the total collected.
So easy to fall into the circularity trap and forget about the final division by area.
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...forget about the final division by area.
This is true, but the area to be considered is the area per pixel. A larger sensor can give you more pixels of same or smaller size, or same number of larger pixels or ...
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At best this is confusing because people in general do not discern intensity and pixel area. Intensity will not change any way.
Pixel independence is another can of worms and despite the obvious issues associated with it might lead us down a more rewarding lane of explaration.
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To me, the true advantage of a larger sensor (format) is that the same gradation spreads in the wider area, and thus the tonal slope is less steep than that on smaller sensors, which creates more pleasing tone and atmosphere.
In this image of Michael, the gradation of the "glow" of the leaves from the bottom left to the top right is a good example.
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I havent seen a single digital medium format image, that differs from other formats. The only difference IMHO, comes from the editing and use of DOF. I have shot with the 645z many times and the RAW files is no different than those from a 36, 24 or 16 MP camera, just slower to work on in PS. I honestly belive it comes down to the editing and I dont see any special glow to Michaels picture. But that is me. Its a nice image, but nothing that couldnt be done with a normal up to date digital sensor. When it comes to the print, I might see things differently :)
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I havent seen a single digital medium format image, that differs from other formats. The only difference IMHO, comes from the editing and use of DOF. I have shot with the 645z many times and the RAW files is no different than those from a 36, 24 or 16 MP camera, just slower to work on in PS. I honestly belive it comes down to the editing and I dont see any special glow to Michaels picture. But that is me. Its a nice image, but nothing that couldnt be done with a normal up to date digital sensor. When it comes to the print, I might see things differently :)
Part of the reason the difference is small is that the sensor size difference is small. The hassy and Fuji are both mini-medium format. MF is typically 6cm by 6cm or larger.
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It's the DX-FX debacle repeated again.
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It's the DX-FX debacle repeated again.
And always will be...
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If the aperture and shutter speed remain constant photon shot noise is less of a problem with a larger sensor. More total light is collected by the larger sensor. The intensity per/unit of square measure is the same so the larger area collects more. (I hope I typed that sensibly and correctly this time :) If the final presentation is the same, e.g. 11x14" print the color fidelity and noise levels should favor the medium format.
Dave Hartman
I'm sure many money wrenches can be tossed into this none off which involve shot noise (or so I surmise)
I'm not too excited about the mid-medium format camera as it's not a big enough step up in format size to be worth a second set of lenses, that's for me. It's all theoretical for me as the cost of a second system is prohibitive, particularly a medium format system.
Dave
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I don't like photon shot noise like I don't like death and taxes.
Dave
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Only makes sense if the pixels on the larger format also each are larger. The sensor area itself is not the primary determinant. One could as well argue that the larger format confers a potential disadvantage by putting more stress on the optics to be sufficiently corrected to cover a greater image circle and still have adequate sharpness and low levels of colour aberrations.
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You can theoretically produce a scaled version of your lens that should perform the same. I'm assuming no size or weight constraint by the user. Generally the engineering problems come with downsizing stuff, don't they?
The ideal sensor would have an infinite number of pixels and a fill factor of one. You would record the position of each photon, and all the binning and averaging would be done in post. 😄
But we would need faster computers, since there are on the order of 10^12 photons that hit an FX sensor.
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Scaling is not that easy to implement in practice. There may be production or size constraints that limit the degree of what one could diminish or enlarge a given design.
We need to keep in mind that what we mount onto our camera virtually always are mass-production items with all that this entails.
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Scaling is not that easy to implement in practice. There may be production or size constraints that limit the degree of what one could diminish or enlarge a given design.
We need to keep in mind that what we mount onto our camera virtually always are mass-production items with all that this entails.
Yes, I understand that we cannot get this off the shelf and there are practical limitations. I think that a copy of the Otus lens that covers 8x10 would be rather hard to construct. But theoretically, one could make copies of Michael's favorite Zeiss lenses to put on the Hasselblad, and they should not perform worse. The scaling factor is rather modest. On the contrary, they would probably perform slightly better because the same level of absolute tolerance would result in better relative tolerance.
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The "small" Otus for FX carries already a very high price tag. Imagine the cost of an upscaled version with much more heft and smaller potential sales volume. Not convinced Zeiss would embark on such a venture.
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Nikon D700 v. Nikon D700 (http://www.photonstophotos.net/Charts/PDR.htm#Nikon%20D700,Nikon%20D700(DX))
Nikon Df v. Nikon Df (http://www.photonstophotos.net/Charts/PDR.htm#Nikon%20Df,Nikon%20Df(DX))
Nikon D750 v. Nikon D750 (http://www.photonstophotos.net/Charts/PDR.htm#Nikon%20D750,Nikon%20D750(DX))
Nikon D800 v. Nikon D800 (http://www.photonstophotos.net/Charts/PDR.htm#Nikon%20D800,Nikon%20D800(DX))
Nikon D810 v. Nikon D810 (http://www.photonstophotos.net/Charts/PDR.htm#Nikon%20D810,Nikon%20D810(DX))
Nikon D5 v. Nikon D5 (http://www.photonstophotos.net/Charts/PDR.htm#Nikon%20D5,Nikon%20D5(DX))
Hasselblad X1D-50c v. Nikon D810 (http://www.photonstophotos.net/Charts/PDR.htm#Hasselblad%20X1D-50c,Nikon%20D810)
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So, the very same sensor and photo site "knows" its total area is limited, all other parameters being identical? How strange, perhaps we see the marks of artificial intelligence (AI). I cannot see that in-camera processing or later "equivalencing" has been eliminated as a variable here either. Furthermore the graphed data points are from a model not measured. If the model is misleading so will the data and conclusions be.
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Graphs based on Lies, Damned Lies and Statistics?
I keep reading the size of the format is significant, perhaps more than pixel size. This must assume that the image will be printed modestly large, a print for the wall not a mural, or presented on a high quality display. Clearly the exposure must be the same.
Let's say we take a photo with a D810 in DX with a 70/2.8 lens with an exposure of 1/800 at f/5.6 and then one with the same D810 in FX with a 105/2.8 lens with the same exposure of 1/800 at f/5.6. We'll assume the subject is the same and the subject distance is the same. Assuming the IQ of each lens is the same which RAW file will hold the most real data? Now if we make 22x30cm (9x12in) print or a 28x42cm (11x17in) print from the DX and the FX RAW file the potential is the print from the larger collection of data (photons) will make the better print. I'm sure a few monkey wrenches can be thrown in the works but potentially we can make a better print from more data which should be a better sample.
Anyway that's what I've read for a time.
Dave Hartman
Graphs based on DxOMark data?
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The darned "equivalence" approach can be twisted any way one prefers to support almost any supposition one wants.
The crucial point, however, is as follows: will a single photosite "understand" the total area of the *same* sensor is DX or FX? In any case, I find this assumption highly questionable. What happens later during post-processing stages is another issue, but will not influence the basic first stage of light collection, which is per photosite.
I wish there had occurred some kind of peer reviewing of these models floating around on the 'net before too much trust can be placed on the model predictions.
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The crucial point, however, is as follows: will a single photosite "understand" the total area of the *same* sensor is DX or FX?
Of course it won't.
These graphs don't talk to the initial light collection, but to the perceptual magnitude of noise in the final image. That's why he uses what he calls "photographic dynamic range", and not "engineering dynamic range".
When we view images (at a standardized size), we don't examine individual pixels, but integrate information across a finite patch of the photograph. We need to normalize the statistics of individual photosites to reflect this*. This is the only part where a model is applied (rightly so, don't you think?). The photon transfer curves and SNRs are measured values, and the site explains how they were measured.
* To make an example: if you make the photosites smaller, they will each record less photons. But will the image viewed at large become noisier? Perhaps, but only if the higher pixel density leads to a lower efficiency of light collection. When those technological obstacles are overcome, the per-pixel noise will be more, but since the pixels are smaller, the noise will not be more bothersome compared to the lower-MP sensor when the image is viewed at a standardized size. So the graphs that were linked by Dave are, to a large extent, independent of the photosite size.
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I repeat that with the underlying 'equivalence' thinking one can "prove" almost any measure one wishes.
In the referred charts, modelled output based on unspecified or implied conditions deemed relevant to the average photographer is presented as were it to show the DX sensor is inherently inferior to the FX. Or by extension, any smaller vs. larger format sensor. However, careful consideration should indicate this is a largely circular argumentation and results from intentional differences in the output, not the input.
Fortunately, there is much more to actual photography than blindly relying on dubious models and charts.
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I cannot speak for others, but I'm certainly not blindly following anything.
I also don't think that you can prove everything with the equivalence principles, unless you deliberately misuse them or apply them selectively.
Of course I see many people do that, but this is hardly the fault of those that understand them.
In all these years I haven't seen a single experiment that actually genuinely contradicts any of the principles, nor a more concise summary of digital signal processing principles as they apply to photography.
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Any proficient photographer tends to aim for using the best tools for their work. That encompasses choosing the suitable format for capturing the initial image. Sometimes the "best" format is small, sometimes it is larger, but any sane decision has to be based on very different criteria than what can be gleaned for the noisy information available on the internet. Severe abuse of concepts and understanding physical laws are wide-spread to the extent that in some user groups they have replaced the facts.
The inevitable information loss (or introduction of noise, which is the same thing) associated with overall degree of magnification of detail along the work flow from raw file to print should receive much emphasis. It is a basic fact that a larger format needs less secondary magnification to get a fixed print size, but is that a relevant basic for comparison if the end user doesn't care about what format they print to? Can a higher initial pixel count negate the issue of magnification loss, or will we face the apparition few know or care about, the ghost of empty magnification? In fact, with most of the gear available today, we can make final prints much bigger than anything deemed feasible only a few decades ago, unless you had an awkward slow-operating view camera of 4x5" or larger. For viewing on a web page, even a measly 2 MPix model would suffice thus most of our captures are truly overkill in terms of the amount of data captured.
I'm definitively not saying techincal information is superfluous or we shouldn't wish for improvements in sensor technology or camera features, merely pointing out the danger of running in circles to bite one's tail if not allowing less technical aspects to play prominently in our photographic life.
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Yes, I agree with this perspective. It is clear that artistic vision is very important and that for me the fascination of photography is the combination of science and creativity.
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Clearly the exposure must be the same.
Why?
Let's say we take a photo with a D810 in DX with a 70/2.8 lens with an exposure of 1/800 at f/5.6 and then one with the same D810 in FX with a 105/2.8 lens with the same exposure of 1/800 at f/5.6. We'll assume the subject is the same and the subject distance is the same.
If you are going to keep the same perspective and framing, why change the DOF?
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Why?
More exposure less photon shot noise; less exposure more photon shot noise.
If you are going to keep the same perspective and framing, why change the DOF?
It's a gift and one that can't be refused.
Dave
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It's a gift and one that can't be refused.
Usually lenses have adjustable apertures and you can set the depth of field where you want it and format choice should not stop you from making creative decisions like that. Of course there can be limitations (aberrations at wide apertures and availability issues with lenses) but your statement makes it seem like there is no choice. Or am I missing some humor?
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Usually lenses have adjustable apertures and you can set the depth of field where you want it and format choice should not stop you from making creative decisions like that. Of course there can be limitations (aberrations at wide apertures and availability issues with lenses) but your statement makes it seem like there is no choice. Or am I missing some humor?
No, not humor. It's part of a discussion on dynamic range and format size where many contend that a larger format will give more DR than a smaller one because the larger format collects more total light where all else remains constant. This theory may be true or it may not because it's based on DXOMark's, "lies, damned lies and statistics."
I posted a group of links to graphs of various popular Nikon FX camera where the graphs show the same camera in DX format mode gives less DR than it does in FX mode. I think these are a page back.
If all else remains the same, shutter speed, f/stop, distance, angle of view but the format changes from larger to smaller one will gain DoF. It's a gift of the smaller format.
Dave
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Dynamic range is a function of the capacity of the photosite and accuracy in measuring it - noise.
A photosite that is too small will get saturated with electrons when struck with too much light - thereby clipping the highlights. It will also be somewhat more subject to signal noise as the noise is a larger proportion of the electricity being transmitted.
Larger sensors can have larger or smaller photo-sites, or the same size as smaller sensors.
As the constant improvement of digital photo sensors shows, the most important element is not the size of the format as that plays a very small part in the quality of images. The largest leaps in dynamic range are made in the lab and the fab.
I think the rational photographer is one who chooses the format which allows them to achieve their goals.
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If all else remains the same, shutter speed, f/stop, distance, angle of view but the format changes from larger to smaller one will gain DoF. It's a gift of the smaller format.
But if the user of the larger format doesn't need the extra SNR or DR, they can sacrifice that and stop down the lens to match the depth of field of the smaller format. Things were different with film because film speed was basically fixed, so people got used to thinking in terms of what exposure was required to get a good image on a given speed of film. Today the variable ISO and great dynamic range of many sensors allows the user to choose the depth of field they prefer rather than think of it as a side effect of format choice. And diffraction affects the image in a similar way if the depth of field is fixed across formats. So if you've got diffraction limited lenses of sufficient maximum apertures you can get basically the same image from different formats - this is what equivalence theory covers: which settings to use on different formats to get the same image. If your lenses are aberration limited then there is a likelyhood that the larger sensor gives the more detailed image, at least in the center. OTOH your smaller system is smaller. But aberrations are not really covered by equivalence theory.
I don't think there is any controversy really. It's just different generations thinking using terminology they're familiar with and not really understanding each other.
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What I've found is this...
D5 v. D5 (http://www.photonstophotos.net/Charts/PDR.htm#Nikon%20D5,Nikon%20D5(DX))
D5 v. D500 (http://www.photonstophotos.net/Charts/PDR.htm#Nikon%20D5,Nikon%20D500)
D5 v. D5 v. D500 (http://www.photonstophotos.net/Charts/PDR.htm#Nikon%20D5,Nikon%20D5(DX),Nikon%20D500)
What science wants is independent verification.
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Why on earth would a camera sensor have better dynamic range in Dx format than in Fx format? The sensor doesnt know if only a part of it is read out. If you use RAW format, it is the same if you crop the image afterwards. This is pseudoscience and proof to why it is of no value to discuss sensor performance decopled from real world experience. It all boils down to what one find pleasing to ones eye and to what gear one find suited to the task at hand. If one find that MF does the job well, ok, if it is MFT that is equally ok. One doesnt need to draw a curve in a diagram to prove anything. The very existence of Canon users have proven that long ago 8) That is just my two last cents :)
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It's even worse, Børge.
What people discuss are model outputs without even questioning if the model is appropriate or even applicable. Where is the simple consideration of whether circular arguments are introduced in the model chain? I have yet to see these models take into account the basic fact that by comparing two formats printed to a final fixed and similar size, the magnification of detail along the image chain will be different and thus also will the effective aperture. Just the normalisation removes a degree of freedom that later never can be recovered. It introduces circularity.
The only imaginable use of these models is comparing two cameras having the *same* format. Everything else is not only apples-to-orange, it is fundamentally flawed and hence just a waste of time and internet bandwidth.
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It's even worse, Børge.
What people discuss are model outputs without even questioning if the model is appropriate or even applicable. .....
"All models are wrong but some are useful"
Attributed to the late George E. Box, son in law of Ronald A. Fisher who founded parametric statistics and much else besides. Here's the original source if you are interested in reading further:
Box, G. E. (1976). Science and statistics. Journal of the American Statistical Association, 71(356), 791-799.
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What I've found is this...
D5 v. D5 (http://www.photonstophotos.net/Charts/PDR.htm#Nikon%20D5,Nikon%20D5(DX))
D5 v. D500 (http://www.photonstophotos.net/Charts/PDR.htm#Nikon%20D5,Nikon%20D500)
D5 v. D5 v. D500 (http://www.photonstophotos.net/Charts/PDR.htm#Nikon%20D5,Nikon%20D5(DX),Nikon%20D500)
What science wants is independent verification.
As far as I know the numbers come from DxOMark and the analysis is by Bill Claff himself. Both have been described in more or less detail and discussed extensively. What else does "science" want ? Does it want someone to independently repeat DxOMark's measurements ? Who is going to pay for it ?
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Whether input data points are good or bad is immaterial if the model they are used for is not appropriate or is flawed. If the model, however, is sound, then quality of the input obviously matters.
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"Sciene" want anyone to stop measuring the degree of "nothingness" in an empty space of emptyness..
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I opened a separate thread under http://nikongear.net/revival/index.php/topic,5905.0.html (http://nikongear.net/revival/index.php/topic,5905.0.html) for anyone who wishes to further discuss the topic of equivalence.
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What else does "science" want ? Does it want someone to independently repeat DxOMark's measurements ? Who is going to pay for it ?
Yes, that's the idea. If an experiment can be replicated and the results are the same or nearly the same that gives credence to the theories involved. If the experiment is repeated and different results are obtained then something is wrong. Maybe the original theories need refining or maybe they are just wrong.
The object of repeating an experiment is to prove or disprove.
Dave Hartman
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It seems logical that the extra sampling of light, of photons, yields an advantages to the larger image sensor. If and what advantages is another matter. Maybe the graphs of dynamic range are true? Maybe I'm too willing to believe and they will be disproved?
Dave
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A different approach that is carefully constructed to take all factors into account might or might not support the current hypotheses ('theories'). Just repeating something possible wrong won't make the outcome more correct. We need urgently complete independence in other set(s) of data to advance our understanding of these relationships.
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Why on earth would a camera sensor have better dynamic range in Dx format than in Fx format?
(Sorry! I misread your post. Edited.)
The D500 sensor has more dynamic range at low ISO than the D5 likely because of different sensor architectures; sports photographers and journalists likely prefer a camera optimized heavily for high ISO and many wildlife photographers would use the D500 and shoot in relatively bright light. So Nikon (or whoever they work with, Sony etc.) designed each sensor so that it is optimal for the target applications.
The same sensor in DX crop mode does have less dynamic range than in FX, at equal ISOs, unless there is an error in the measurement or presentation. This is because each pixel in the DX image has to be magnified by 1.5x more than each pixel in an FX image to reach the same print size. This magnification makes the noise more apparent.
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Just my point. The "difference" occurs after the data has been captured and is due to processing not true difference in sensor performance.
Ie, just a very convoluted way of stating the obvious, that a larger format needs less overall magnification of detail to reach a fixed print size. A fact that has been known since the dawn of photography. One allegedly blame the sensor performance instead of pointing to the underlying assumptions responsible for the claimed "difference". Take away the fixed print size and what remains of value in the model output??
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Comparisons between algorithms, instrumentation, technologies or products usually involve each contestant performing a fixed task. I don't think any methods or instrument focused scientific journal would publish a comparison where the tasks performed by two methods are different, or evaluated using criteria which is not the same for each method.
You can use several different tasks and metrics if you want to gain a more in depth understanding of the advantages or disadvantages of each method. For example a big lawn mover might finish an acre faster than a smaller one, but the smaller one is more dexterious and can reach places where the larger one can not. So the speed of covering a large field might not be the most important metric. Still it seems not very scientific to present the following comparison result:
Lawn mover 1 finishes a town in a fortnight
Lawn mover 2 tweaks a home lawn in an afternoon.
It is difficult to grasp these results as to what exactly the relative performance was, since the same task or metric were not used and they were not precisely defined (even though the above speed evaluations might appeal to some for their practical value to a common person, they would not be considered scientific).
As long as the methods are described clearly, and the experiments are correctly carried out and presented, one can find value in the numerical data that is presented. Of course, a truly comprehensive analysis of a camera's performance needs to consider lens availability, focusing, etc. all factors which contribute to the experience of the users. But there is a lot of fixation on the numerical data these days. This is not a good or bad thing in itself, it is just important to remember that this is only a part of the story.
Personally I value greatly the viewfinder quality of the cameras that I use. Yes, it is subjective, but it has an important role in my experience of the photography process and also indirectly influences the outcome (and sometimes directly as well as the information I get through the viewfinder is different and that influences my choice of when to take the shot). And ultimately my personal experience is what drives me to do photography, not some numerical performance criteria. That doesn't mean the numerical criteria isn't of some value. I enjoy the D810's super silky smooth tones at ISO 64 and the quantitative sensor performance evaluations give some rigorous validation of the subjective findings. However, when I'm photographing people, I usually use the D5 as it gives me a very high rate of focus keepers and so I don't have to lose shots to slight misfocus as much as I used to and above all I don't have to spend as much time editing. In this situation I choose the metric which is more important to me. I think the cameras have been fairly described in reviews - there is discussion of the dynamic range, and autofocus capabilities. For me the D8x0 always put me in an uncomfortable place focus-wise; the D810 is an improvement over the D800 in that respect (and many others) but the D5 really kicks the (autofocus) ball right out of the park.
Although ergonomics, viewfinder and AF are important criteria for me, I still always check the numerical sensor data as well, as they give me important information on what I can expect image quality wise. I have not been disappointed by the much-criticized D5 base ISO dynamic range because I knew to expect it and I've been very pleased with the results from ISO 1000 to 25600. Without the measurements I would probably try to try to shoot at low ISO and wonder what's going on when the image looks a bit rough. In my figure skating photography with the D810 (and D800 before that) I was only happy up to ISO 1000 and even ISO 2000 seemed a bit noisy especially if I had to crop. With the D5 I can shoot at ISO 6400 with impunity and while it obviously isn't quite as good as D810 at ISO 1000, it gives me additional options as to what kind of lens I can use for this application, such as the 300/4. I've shot wedding dance at ISO 8000-11000 and been very happy with the image quality of the prints, something that would have been totally outside of the domain of the D800 or D810 in my view. So by checking the quantitative sensor data I was able to start on the right foot and use each camera for where it excels rather than go on a rampage about the D5's base ISO image quality. Which is still fine, not the best by today's standards, but at least the shots are in focus. I was testing the D5 and 300 PF at Helsinki City Run on Saturday to get some practice and to get a feel for whether it would be better to use the D810 at this week's two outdoor fashion shoots for its low ISO DR. If I shoot with the 300/4 PF the D810 nails the focus most of the time but not so much with the 200/2 - in backlight the camera is likely to pick on the brightly lit, high contrast detail in the hair which is several cm behind the eyes and so shots are likely to be backfocused in this scenario (I actually trick the system by subtracting 1 or 2 points from the normal focus fine tune value to increase my odds). The D5 has enough AF sensitivity and specificity to focus on the facial details without being lured by the brighter, contrasty hair most of the time. And I think the DR will be ok as long as I don't make a gross misjudgment of my exposure.
(Sorry, I always seem to slip onto the topic of AF in any sufficiently long post.)
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Take away the fixed print size and what remains of value in the model output??
A smaller print? :)
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In the referred charts, modelled output based on unspecified or implied conditions deemed relevant to the average photographer
The output is not modeled it is measured from raw test images.
Nothing is unspecified it is all documented on the site.
Assumptions are made (and stated) regarding visual acuity and reference is made to well established (eg. ISO) levels of acceptable SNR.
I think that's relevant to the average photographer.
FWIW, I think this test is better designed to provide relevant information than the "equivalent" DxOMark Landscape (print) score; and feedback from photographers indicates that many agree.
is presented as were it to show the DX sensor is inherently inferior to the FX. Or by extension, any smaller vs. larger format sensor. ...
There is no intent to show anything. The measurements speak for themselves.
You could interpret it that way but like anything it needs to be put into context.
That said, the results are unsurprising.
Since this is a measure normalized to a fixed print size and viewing distance; the smaller sensor area must be enlarged more and suffers more loss in quality.
Surely no one expects a small crop from a full image to retain the same image quality when both are enlarged to the same size; this is no different.
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As far as I know the numbers come from DxOMark and the analysis is by Bill Claff himself. Both have been described in more or less detail and discussed extensively. What else does "science" want ? Does it want someone to independently repeat DxOMark's measurements ? Who is going to pay for it ?
To clarify ... everything in the first section of my site, for example Photographic Dynamic Range (http://www.photonstophotos.net/Charts/PDR.htm), are from my own independent measurements.
The second section comprises measurements that are derived from DxOMark data.
This is provided largely because they have tested more cameras.
Also as a resource for those who had become accustomed to getting data from sensorgen (which still exists but is not longer maintained).
And finally, as a cross-check.
So in the second section you would find DxOMark Derived Photographic Dynamic Range (http://www.photonstophotos.net/Charts/DXOPDR.htm)
Same PDR methodology using DxOMark data rather than my own.
Although I don't repeat DxOMark's methodology I do think a valuable cross-check already exists in PhotonsToPhotos (http://www.photonstophotos.net).
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To clarify ... everything in the first section of my site, for example Photographic Dynamic Range (http://www.photonstophotos.net/Charts/PDR.htm), are from my own independent measurements.
The second section comprises measurements that are derived from DxOMark data.
This is provided largely because they have tested more cameras.
Also as a resource for those who had become accustomed to getting data from sensorgen (which still exists but is not longer maintained).
And finally, as a cross-check.
So in the second section you would find DxOMark Derived Photographic Dynamic Range (http://www.photonstophotos.net/Charts/DXOPDR.htm)
Same PDR methodology using DxOMark data rather than my own.
Although I don't repeat DxOMark's methodology I do think a valuable cross-check already exists in PhotonsToPhotos (http://www.photonstophotos.net).
Thank you.
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We agree on the effect of secondary magnification and that'll suffice for me. Again, just bringing the focus (sic) back to what was known centuries ago.
I can attest to the fact that in practical field situations, the 'theory' plays no role for the final image. We do not make the "same" images with different gear, which is a nonsensical approach, we use the best tools for the purpose or even whatever tool is at disposal.
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In the days of film I never owned a half frame camera. I would still have used Tri-X as my primary film. I would still have made 8x10" prints just like with a full frame 35mm camera. I would not have liked the increase in grain form the extra enlargement required. I would not been able to crop images and accept the grain. The loss of image quality would have been too great for me.
Today my primary format is 36x24mm (FX, FF). I would make most use of a D5 if I could afford one. I don't believe in equivalence. If you need a medium format camera you can't make a DX or FX camera do medium format. I would find 24x16mm (DX, APS-C) as available in the D500 very useful. I can but dream of a medium format digital camera.
I hope Michael continues to enjoy his Hasselblad X1D and finds the lenses that facilitate his photography.
Dave
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I agree with David. Good to hear Michael is using his gear for making images.
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I can attest to the fact that in practical field situations, the 'theory' plays no role for the final image. We do not make the "same" images with different gear, which is a nonsensical approach, we use the best tools for the purpose or even whatever tool is at disposal.
Right but you have decades of experience and use that to decide what gear to use.
Someone with no experience can use theory to get an idea of what can be expected using a particular setup in a particular situation. This is helpful to get started. An author doesn't usually refer to grammar when writing a novel or a poem but nevertheless grammar was taught at school and this education likely contributed positively to their writing skills.
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I don't believe in equivalence. If you need a medium format camera you can't make a DX or FX camera do medium format.
It's not a question of a religious belief but the theory comes from basic physics and geometry and has been experimentally validated.
Under diffraction limited conditions you can get the same image using a medium format or small format camera, to a good approximation. I will be happy to demonstrate this some time (with FX and micro four thirds, the formats which are available to me) when I have time to set up the experiment.
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SELLING MY X1D
After shooting some 1100 or so shots with the Hasselblad X1D system, I have decided that it is not what I need for my work. I’m sure, many will point out that I don’t get it, but I am only trying to “get it” for my own work. It’s embarrassing to admit this, after all my praise, but at my age, who cares? I have put my X1D system, including the 45mm and 90mm lenses, plus the lovely RSS L-Bracket and 5 batteries for sale on Ebay under my nickname ALLMUSIC.
Although there are a number of druthers and small reasons for giving up the camera, the two main reasons are:
(1) The lack of lenses I need now for the camera. I have waited months for the 30mm and, of course, probably will would have waited for the announced 120mm Macro, as well. This is summer, and now is the time I need those lenses. As a close-up photographer, neither the 45mm or 90mm can get me close enough, especially since there are no extensions available.
(2) And secondly, having very carefully done hundreds of test shots for overall sharpness, I am, despite what others say, disappointed with the degree and kind of sharpness I can attain with the X1D system and their lenses. Please don’t ask me to prove this. It’s just my opinion.
No one is more sorry than I am, and perhaps selling this system is a stupid thing to do. I lose a bunch of money. Or, is it that I’m hooked on the Nikon system and how the D810 works? I am not arguing that the D810 IQ is better than the X1D, but only that what I am able to get from the X1D is not worth what I have to put up with to get it. And, of course, there are all the great lenses I have that will never work on the X1D, but that is a minor thing.
And finally, for me and the work I do, the X1D is just not ready with what I need. I should have waited for perhaps the second edition. And, I can always get another copy, should an X2D comes out. Meanwhile, I will wait for the rumored 46 Mpx D820 and have to be happy with that. I have TRIED to love this system, but I can’t get there from here.
I will say that the X1D haptics are extraordinary and that, if I wanted to afford what for me would basically be a $20k system, I would keep it. The system is easy to use and I love the touch-screen of the LiveView.
So, there you have it. I report this because I owe it to those who have read any of my other comments on this system. C'est la vie
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A very fair and succinct summing-up of your decision and the underlying rationale. Kudos.
This also confirms my conviction that photographers basically are more interested in what they can achieve rather than any numeric specification of the same, however enticing the latter might be on paper.
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Thank you for the update Michael!
I can relate to your findings.
Good luck with the sale :)
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I could add a little more. I am also (equipment-wise) totally exhausted from purchasing and vetting the Pentax K3 and K1, the Fuji GFX, the Sony A7R2 (for the second time), and the Hasselblad X1D, including all the trimmings for each system. All of this in an attempt to reach beyond my current D810, since Nikon has not ponied up. So... here I am with my D810, which for my work is better than any of the above. My GAS is finally satisfied. Enough.
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Long term Review of the X1D by Ming Thein
https://blog.mingthein.com/2018/01/31/long-term-review-the-hasselblad-x1d/