Larger Sensors Do Matter

[Michael Erlewine]

At least, that’s my opinion. I got into a large sensor because I was curious about medium-format cameras and was able to pick up a used Hasselblad X2D at a reduced price. And even at that price (with a few lenses) I have to pay, pay, pay, and I am selling some fifty lenses and other equipment to do just that. What follows here is for the very few that are interested in focus stacking in some detail.

I have written elsewhere on this forum something about my experience with the Hasselblad X2D, which was a good one, so I will spare you the details here. Instead, I just want to discuss the obvious effects I see in using a large sensor, in this case the 100 MP sensor in the Hasselblad X2D.

Up until now, I have thirsted for a larger sensor from Nikon, but they have not obliged, so I’ve been stuck with the 45.7 MP stacked CMOS sensor (35.9x23.9) that are in the various Nikon Z cameras.

Of course, Sony now has a 61 MP mirrorless, etc. Nikon has not delivered anything more that 45.7 MP so far.  Perhaps they will bring on one this year, 2024!

With that withstanding, while I could opine on the helpful features of the Hasselblad X2D, as mentioned, here I am just determining how a larger sensor helps my closeup photography and in particular focus stacking. And in particular how I can salvage for use all my old F-mount lenses!

To begin, the Hasselblad X2D has the following ways to shoot closeup and can take the following adapters.

First of all, there are the native Hasselblad lenses, the XCD class of lenses, some 13 or so to date. These work flawlessly with the XCD. There are adapters for the older Hasselblad lenses, but something is lost and my reading of many blogs on the subject suggest that it’s not worth going for the older types of Hasselblad lenses, like the HC/HCD, HX, and so on.

You can read about how these earlier lens systems disappoint and make life difficult (IBIS does not work, vignetting, and on and on). I’m not even going to try this approach.

I am sticking with the native XCD lenses, an adapter for Nikon F lenses, and purchasing a Hasselblad X2D adapter for my technical camera, the Cambo Actus-Mini (G), where the X2D becomes the digital back, and we can put whatever we want on the front end of the technical camera we wish.

I very much like the Hasselblad XCD lenses, yet the ones I have are not very fast and I miss the fast wide-open APO lenses I collect. I know, there is the XCD 80mm f/1.9, but I am still saving my pennies for that one. Yet, even if I had all of the XCD lenses, they are not geared for close-up photography and don’t have very closeup reproduction ratios.

Even the only macro lens in the XCD set, the 120mm f/3.5 has a reproduction ration of 1:2, only half the way there. Here is the list.

HASSELBLAD REPRODUCTION RATIO

120mm  F/3.5 1:2   at 1.41 feet
45mm P F/4   1:5.2 at 13.8 inches
65mm   F/2.8 1:5.4 at 1.65 feet
90mm   F/2.5 1:5.8 at 26.4 inches 
135mm  F/2.8 1:5.8 at 3.28 feet
38m    F/2.5 1:6.2 at 11.8 inches
45mm   F/3.5 1:6   at 1.31 Feet
28mm   F/4   1.6   at 8.7 inches
55mm   F2.5  1:6.4 at 17.7 inches
80mm   F/1.9 1:6.4 at 2.3 feet
21mm   F/3.5 1:9.6 at 1.31 feet
30mm   F/3.5 1:9.6 at 1.31 feet

35-75mmF/3.5-4.5 0.15x (bad) at 1.


Lloyd Chambers in a personal conversation wrote “XCD lenses are all engineered for rigorous performance.   Totally opposite of Leica SL lenses.”

OK. I can see that from my use of them, so how am I going to let a little more light on the subject and get wide-open lenses? That’s what I am looking at here.

As mentioned, it’s not going to be through the set of XCD lenses, so I’m going to have to improvise, something that I have been forced to do a lot of in my photography over the years. I like it.

NIKON F-MOUNT ADAPTER

A good first step is to pick up the adapter for the X2D that allows mounting any of our old F-mount lenses. Of course, I have been busy adding the new Nikon Z “S” series lenses for use with my Nikon Z7II and Z8 cameras. Well, none of those lenses will be any help because they can’t be mounted on the Hasselblad X2D, not ever.

There is something like a small difference between the Z and the XCD lenses which give us about zero room to adapt anything. So where does that leave me?

One good thing is I have a lot of really good APO quality lenses with the older F-mount, lenses like the Leica 100mm Elmarit R, the Coastal Optics 60mm, and so on. These all fit nicely on the X2D and while they don’t electrically work, if I fiddle with the controls available to me, I can have all their virtues on the X2D, and do. Very helpful.

And so, I’m busy digging through my old lenses for lenses fit for the X2D, even rescuing a few from Ebay sales, because I put them up for sale.

Suddenly I have a bevy of fine lenses that will mount on the X2D Nikon adapter for F-mount lenses. Wow. Glad I didn’t sell these beauties! I even mounted my Zeiss 135mm f/2.0 lens (to me an Otus) on the X2D, one of the sharpest lenses I know of.  And there is another treasure trove open to us as well.

And that is via technical cameras. I have had technical cameras for years, a whole line of them, all the way back to the 14-pounder technicals I could barely mount on the tripod.

I got rid of those and settled for the Cambo Actus-Mini (G) camera which has an adapter mount for the Hasselblad X series cameras. It does not have all the bells and whistles that the really heavy cameras do, but has more than I need, tilt, shift, and all of that.

With the Hasselblad X2D as a digital back on the Cambo Actus-Mini (G), I suddenly have a wealth of options, including my whole collection of Large-Format lenses that fit in Copal this and Copal that.

In addition, many of the small Nikon F lenses will also fit on the Actus Mini’s front standard, another group of lenses that produce good images, which brings me to my last point here, the basic methods of focus stacking images.

I also had a Mamiya RZ67 and a bunch of lenses back in the day, so I’ve flirted with medium format over the years.

I’ve been focus-stacking for decades and can well remember right here on NikonGear when folks used to argue whether it is cheating to stack focus? We’ve come a long way since then!

It is important to remember that it makes a difference (to the stacking software) how we stack the photos in the first place. There are three popular ways to photograph stacked layers, and some are more artifact-prone than others. The key is to move the entrance pupil of the lens as little as possible.
If you are going to stack photo layers, there are three basic ways to do this, each successive one is better than the last, so here they are, starting with the least adequate method:

(1) WORST. Mount the camera and lens on a focus rail (which is on a tripod) and gradually move the unit (camera and lens) along the rail toward the subject being photographed. This is the least efficient way to focus stack and is liable for the most artifacts.

(2) BETTER. Mount the camera and lens on a tripod and turn the lens barrel (helicoid) in as ‘fine’ a way as possible. Lenses with a long focus throw make it much easier to so this. If the focus throw of the particular lens is too short, we are forced to use the rail method.

(3) BEST. And finally, the superior method (that will cause the least artifacts) is to fix the lens on a bellows (on a tripod) so that the front standard with the lens is fixed and mount the camera on the rear standard of the bellows. Then move only the rear standard (and camera) to focus. This method holds the entrance pupil in the lens stationary and moves only the camera. This is the best way to stack focus.

So, there you have my plan moving into the future. Of course, I like the Hasselblad X2D and its take on color. Yet that alone is not what I am enthused about. I see a great future for many of my old Nikon-F lenses although it involves a fair amount of fiddling on my part, which I am happy to do.

It seems I have been fiddling with photo gear since 1956 when I got my first Kodak Retina 2a, a set of closeup lenses, a tripod and light meter.

The Hasselblad X2d on the Cambo Actus-Mini (G) and the APO El Nikkon 105 enlarging lens on the front standard.

[Akira]

The biggest reason for me responding less and less to your posts of the results of stacking experiments is that my all-too-humble monitor is not qualified to appreciate the advancements of the image quality.

The cheapest way to achieve the (3) BEST option would be to support the lens and the camera at the filter thread of the lens and rotate the helicoid gradually.  That would burden the helicoid too much, but a decent lens and a light camera like SIGMA fp might work.

[Michael Erlewine]

The biggest reason for me responding less and less to your posts of the results of stacking experiments is that my all-too-humble monitor is not qualified to appreciate the advancements of the image quality.

The cheapest way to achieve the (3) BEST option would be to support the lens and the camera at the filter thread of the lens and rotate the helicoid gradually.  That would burden the helicoid too much, but a decent lens and a light camera like SIGMA fp might work.

The Cambo Actus-Mini (G) technical camera is easy to use and does a great job of holding the lens fixed and moving the rear standard, IMO.

[Birna Rørslett]

Fixing the entrance point in space only means you have a perspective invariance. Magnification and therefore optical aberrations will and do change.

With a focusing rail, magnification -- and  hence many optical aberrations -- are invariant. However, perspective will change and any geometric distortion can factor into the outcome as well.

When the lens itself is used for focusing, magnification, aberrations, and perspective, all change during the captures.

The software packages differ in their abiity to juggle all the variables towards a best solution. The subject itself is also important since fine detai like air or antennae can cause troubles for the stacking program.

For real close-ups and true macro work, including microscope usage, all methods can work passably well. For really 'deep' stacks of the 'infinite landscape' type where small foreground is combined with far away objects, perhaps the fixed entrnce point approach is better. However, again the subject is a part of the whole.

[Birna Rørslett]

I did make a fixed entrance pupil setup using an old Olympus OM 28mm f/3.5 lens, a cut-down bellows, and makeshift bellows material inbetween. It did work, but was awkward for field use, so now I tend to use tilt/shift lenses instead for such cases.

With an FTZ or similar adapter, it should work on the Z cameras. Perhaps time has come to search the cupboards for my old invention?

[Michael Erlewine]

I did make a fixed entrance pupil setup using an old Olympus OM 28mm f/3.5 lens, a cut-down bellows, and makeshift bellows material inbetween. It did work, but was awkward for field use, so now I tend to use tilt/shift lenses instead for such cases.

With an FTZ or similar adapter, it should work on the Z cameras. Perhaps time has come to search the cupboards for my old invention?

Yes, please do and explain to me how to make one myself please. Right now anything I can get on my Actus-Mini (G) works very well, where the front lens is fixed and the rear standard moves forward. I can put all kinds of lenses on the front standard: Copals, small lenses, and on and on. I also have small and larger bellows so that I can get as close as I can to closing down and not be limited by many bellows frames.

Also, I have a Hasselblad to Nikon-F adapter that works very well, so all my F-mount lenses work well. Nothing I can do (is there?) to get the Nikon Z lenses (which I have been aquiring) to work with the Hasselblad X2D?

Of course the Hasselblad XCD series of lenses are very good, yet are almost all oriented toward landscape rather than closeup, which is what I do. Even their one macro lens is only 1:2, etc.

I am looking into to getting an adapter for Mamiya and trying related closeup lenses and see how that works.

I have spent too much money on all this and have to budget down a bit. I am selling about 50 of my lenses, although as I see how well this 100 MP sensor works, I have been cherry-picking Nikon-F lenses I could still use off of Ebay where I have them for sale. LOL.

Most of all, aside from the rather nice "color science" of the Hasselblad, I am impressed by what can be done with a larger sensor and wonder why Nikon has not blessed us with a 60MP or 100MP camera yet, in which case I could use all my Z "S" lenses.

I can get a Hasselblad camera mount....and a Nikon Z lens plate (if there is one) and build something like you mention. I need some guidance please.

[Bob Foster]

From Michael:

Nothing I can do (is there?) to get the Nikon Z lenses (which I have been acquiring) to work with the Hasselblad X2D?

I wondered about this also. Having looked at my X2D body I concluded that an adapter that allowed the full focus range of Z system lenses, while possible, would render the camera unusable with XCD lenses.

An adapter that is also a short extension tube for the Z lenses is possible, but to the best of my knowledge, not commercially manufactured.

Top quality symmetric lenses (like the Apo EL Nikkor) as well as variable β lenses (like the Schneider Macro Varon) often perform superbly with extension.

I have been less happy when using extension with many, but not all fairly recent lens designs. In the case of Hasselblad extension tubes were available for the HC and and HCD lenses. The shortest extension tube (13mm) worked passably for many users that did not need the highest IQ with HC 80 (close to a classic symmetric design) and less well with the HC 100 (not so to a classic symmetric design).  Given the more recent lens design I suspect, but do not know, that this is at least a significant part of why Hasselblad does not offer extension tubes for the XCD system. Third party extension tubes are available.

The HC 120 Macro II (orange dot) lens produces much better results than use of extension tubes with either the HC 80 or HC 100 though it does not produce results quite as good as the XCD 120. It does go to 1:1 magnification. This lens has considerably better color correction than its' predecessor. With the XH adapter and lens firmware 19.1.0 autofocus will not work, but despite what current the X2D manual states stacks can be made with the camera using the same procedure you would use to have the camera execute a stack with the XCD 120.

Many users of the Mamiya  macro lens are happy. I haven't tried it myself. YMMV. The (used) Mamiya lens is priced so much more reasonably than the (used) Hasselblad lens that if I did not own the Hasselblad HC 120 Macro II (orange dot) lens I'd be try the Mamiya first.

Bob

edit: clarity

[Michael Erlewine]

From Michael: 

Top quality symmetric lenses (like the Apo EL Nikkor) as well as variable β lenses (like the Schneider Macro Varon) often perform superbly with extension.

Bob

Yes they do. I have both those lenses and would not part with them.

I am surprised how a larger sensor, in this case 100 MP, clarifies an older lens. I have the original Nikon 70-180 Zoom lens and started out with that many years ago as a main lens, but have not used it for years because it is not as sharp as I like. However, I tried that lens yesterday with the the Nikon-F adapter to the X2D and got quite acceptable results. I include a photo here.

Hasselblade X2D and the Nikkor 70-180 Zoom.. f/4.5...older one.

[Bob Foster]

Michael,

Comparison of the two photos speaks for itself.

Bob