How Many Mega Pixels Is Enough???

[BruceSD]

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I'm a serious amateur photographer.  I used to print my digital images on a large format Epson roll printer.  In time, I found that I had no use for giant 24 x 36 inch prints.

A year ago I switched to desktop printer (Epson ET8550).  Now, my largest prints are 12x18 inches.  I can not see myself ever making prints larger than 12x18 again.

I carefully compose my images in the viewfinder and almost never crop.

I have 3 Nikon mirrorless cameras (Z6, Z5ii, and Z7).  The 24 megapixels from the Z6 and Z5ii are probably more resolution than I'll ever need.  I'm thinking of selling the like new (2,348 clicks) 45 megapixel Z7, but am hesitant  to list it for sale, thinking some day I might regret it.

Can any of you think of a good reason why I should keep the Z7?

Thanks

[MEPER]

If you mostly take pictures handheld I think 24 MP if fine. You also get better ISO performance than the 45 MP sensor.
To utilize the 45 MP sensor you need a tripod?
Could be an interesting test to take handhold pictures with both and check the details in the pictures and see if you get more "real" information using the 45 MP sensor.
You could perform such a test?

What is a realistic price for a Z7 sold private?

12 x 18 inch prints then 24 MP should be enough. Then you can do 300 DPI prints?

[Bruno Schroder]

I like more pixels for nature macro work. The little reframing of zoom effect you get from cropping is often useful, particularly for insects.

[aerobat]

Bruce, I don't often feel that I need 45MP but this sensor has a very nice dynamic range.
As said before it's very good for nature where a lot details can be useful.
On the other hand I more often prefer the low noise of the 24MP models.
That obviously largely depends on your use case.
But then 45MP can also be downsampled to 24MP in order to get rid of part of the noise.
If Nikon bring a new Z8 II with say 80MP I wouldn't be too interested unless some other specs like dynamic range would improve drastically.
It seems a plateau has been reached with current CMOS technology. I don't know how far away a radically new sensor type may be.
 

[Birna Rørslett]

My answer is: it depends.

Meaning, having lots of MPix might help sometimes when you crop, for example. This also allows using DX lenses on FX cameras and stll have a useful pixel number.

I would keep a Z7 to use for special occasions. Otherwise, 24 MPix is sufficient for nearly all normal purposes. An original version Z7 has fallen drastically in price. Not worth selling in my opinion.

To put this into perspective:  I have printed 4x6m photos from 6MPix RAW files. It would be easier and preferred to have more, but the scene was the most important to the client.

[BruceSD]

What is a realistic price for a Z7 sold private?

I did some research on the price of a used Z7, and I listed my Z7 (with extras) for sale on eBay for $1,200 USD.   https://www.ebay.com/itm/136623361590

If sold direct (and not through eBay), I would hope to get $1,100 USD.

I do thank everyone for your excellent comments.  So far, I'm not convinced to keep the Z7.
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[paul hofseth]

In principle given sharp enough wideangles and steady camera support many pixels would make other lenses unnecessary since the crop-zoom would take over.

p.

[Ilkka Nissilä]

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I'm a serious amateur photographer.  I used to print my digital images on a large format Epson roll printer.  In time, I found that I had no use for giant 24 x 36 inch prints.

A year ago I switched to desktop printer (Epson ET8550).  Now, my largest prints are 12x18 inches.  I can not see myself ever making prints larger than 12x18 again.

I carefully compose my images in the viewfinder and almost never crop.

I have 3 Nikon mirrorless cameras (Z6, Z5ii, and Z7).  The 24 megapixels from the Z6 and Z5ii are probably more resolution than I'll ever need.  I'm thinking of selling the like new (2,348 clicks) 45 megapixel Z7, but am hesitant  to list it for sale, thinking some day I might regret it.

ET8550 is not archival. I'm wondering if you considered how long you want the prints to last when choosing this printer.

Can any of you think of a good reason why I should keep the Z7?

Thanks

In another thread you suggest mainly shooting at base ISO. The Z7 base ISO (64) has a larger dynamic range (and tonal range and color sensitivity) than the ISO 100 base ISO of Z6 or Z5II. So, photos from the Z7 will look smoother with nicer colours and less noise per area, not to mention more detail, given that they're shot at base ISO. At higher ISO settings the Z5 II and Z6 may have advantages, though.

The ET8550 is not archival. Have you considered the lifetime of the prints in the printer choice?

[BruceSD]

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Good points Ilkka!

I am not concerned about "longevity" of my prints.  If they degrade, fade or are damaged - I can print another identical print in minutes.

Pigment prints last what, 100 - 200 years?   The ET8550 dye prints have better color fidelity and last only 50 - 75 years.  That's many years longer than I'll be around...

[Ilkka Nissilä]

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Good points Ilkka!

I am not concerned about "longevity" of my prints.  If they degrade, fade or are damaged - I can print another identical print in minutes.

Pigment prints last what, 100 - 200 years?   The ET8550 dye prints have better color fidelity and last only 50 - 75 years.  That's many years longer than I'll be around...

It depends on the conditions, but the most obvious difference is if displaying prints without (glass) frame: Epson Ultra Premium Photo Paper Luster with ET8550 is rated 26 years (ozone resistance not yet tested) by Wilhelm Imaging Research and P900 (pigment A2 desktop printer) with Epson Premium Luster is rated > 250 years and unprotected resistance to ozone >100 years. Now, none of us will live that long obviously, but I would like something of the effort to exist even when I do not. I am sure that no one will ever go through my original files and print them to keep my work but I think some prints might be kept around. Maybe I am optimistic. ;-) The reason for my interest in print permanence is that under some conditions I found Epson dye-based prints to change color noticeably in only a few months (I had an air cleaner which probably produced ozone that resulted in this print color change). Thus I switched to pigments (around 2005) and have been printing with them since. None of my prints made with pigment inks has noticeably changed in the 20 years. 

If you keep your prints away from light or use a glass frame to protect displayed prints, ET8550 should be fine (89 years) and P900 more than fine (>400 years). In that sense things have improved from the early days. But my trust in the dye-based printers will probably never recover from my past experiences.

[Akira]

The late NG friend Dave Patterson who was retired professional photographer once told me and Mike (Selby) about his experiments to know the amount of megapixels needed for professional quality prints.  He concluded that 9MP is good enough for the 60cm wide print.  He added that a friend of his, who was also professional photographer and was more critical than Dave about the quality of the print, had said that even 180dpi is good enough for the professional quality print of the same size.

If you only need to print of the size up to 18"x12" (46cm x 30cm), the result of Dave's experiment would offer good food for thoughts.

[Birna Rørslett]

I am fortunate enough to have one of Dave's fantastic prints having on my wall. It's 90 by 100 cm. The motif is Japanese maikos chattering at afternoon. Absolutely stunning in every respect and he told me when I selected the print that it was approx 20 MPix if memory serves.  Image smoothness and perceived sharpness both are sublime. He obviously knew, as a life-long professional photographer, how to do his post processing. RIP, dear Dave. I am reminded of you every day when I go past your wall print.

[Ilkka Nissilä]

The late NG friend Dave Patterson who was retired professional photographer once told me and Mike (Selby) about his experiments to know the amount of megapixels needed for professional quality prints.  He concluded that 9MP is good enough for the 60cm wide print.  He added that a friend of his, who was also professional photographer and was more critical than Dave about the quality of the print, had said that even 180dpi is good enough for the professional quality print of the same size.

If you only need to print of the size up to 18"x12" (46cm x 30cm), the result of Dave's experiment would offer good food for thoughts.

I don't want to be discriminating based on age, but young people typically see a lot better and in creating the print, it's probably not a good idea to do it based on the vision of retired individuals. Some fully functional retired people can't see the difference between standard and high definition TV and seem to think such a difference is relevant to no one. I recall one well-known landscape photographer online at one point suggesting that increasing original resolution to 1000 ppi of inkjet prints was useful and produced visible improvements in print quality but later he seemed to be of the opinion that most people can't tell the difference between point and shoot and medium format in a printed landscape image ...

I personally think that it depends greatly on the individual what they can see at optimal reading distance away, and how good their vision is, are they used to evaluating the quality of photographs etc. also how they value certain aspects of technical image quality such as detail. 180 ppi may be OK if the print is large and viewed from far away, but for making small to medium prints to be viewed at reading distance away I print at 360 ppi (or however much resolution there is in the file, it doesn't have to be the same number for every image). For large prints it may not matter what the resolution is at the ppi level as the typical viewing occurs so that you can see the whole image in one glance. If the goal is to walk to the large print and inspect it very closely then 180 ppi may not be enough, at least if the original is very detailed. "Enough" is highly subjective. Content is still (of course) much more important than detail, but if the content is such that fine detail is important to convey it then the print should be made at the highest possible quality available (and that's not going to be 180 ppi for small prints).

A higher resolution original (if shot at a wide to medium aperture) also prints with a softer transition between in and out-of-focus areas, and one could say the higher-resolution original looks more natural as the pixel count is not limiting where the detail stops being finer as the areas truly in focus are approached.

[Akira]

I've heard that Nikon settled on using a 6MP sensor on their D1X because the professional photographers required that pixel count becuase they need that resolution for the image filling a spread page of an A4 size magazine (which equals to A3 size).  They felt that 2.7MP of D1 was only enough for the full A4 size print.  It should be safe to assume that the professional photographers meant the working photographers of every possible age demographic.

FWIW, in Brna's old review of D1X, she (he at that time) compared the resolutions of D1, D1X and Fuji Velvia film (shot with D5, namely the 135 film and scanned) here (parton me for the direct link to the page):

http://www.naturfotograf.com/D1X_review.html

The comparison of the small crop of the "famous" brickwall images clearly tells that the 6MP D1X clearly outperformed Velvia in 135 size.  Even the lowly D1 image looks slightly sharper than Velvia.

Admitting that we (in all age demographic) are spoiled by the images of the digital cameras with much higher MP sensor, the practical resolution should be much lower than we think.

[MEPER]

Years ago I had a trip to Scotland together with a friend. I used Nikon + Velvia and my friend used Canon 1D Mark II (8 MP).
We agreed to do a test and we set up both cameras at tripod and framed the same image.

The frames are here and a couple of 100% crops from both:
https://pbase.com/mxp/velvia_and_dslr

I think if you search the topic Velvia vs. digital you see some claim that Velvia 50 resolution correspond to about 24 MP.

When I got my Nikon D2X I sold my Hasselblad equipment when I found out that my A3+ prints was as good as the scanned 6x6 frames (Coolscan 9000).
Then I did not care about all those tests anymore. The D2X files were much smaller and cleaner and were much easier to work with in editing programs.

The Scotland images was from a time when I was still a "film believer" and I did a lot to convince myself and other.
That said I did the test above as objective as possible. I got the Canon image already processed as a .jpg file from my friend.