So how many pixels are enough?

ggbutcher

Capt_Spaulding said:

@ggbutcher - I was initially wondering how much difference going from an eXpeed4 to an eXpeed6 "in-camera" engine mattered if you were exporting RAW files to a third party converter.

Your project sounds really interesting. The various post processing software makers all claim to have the "best" RAW converters and, while I can see differences, what it means is mostly opaque to me.

When you finish I'm hoping you can do a "for dummies" version.

Good luck - stay well

PS: Just did a little reading/watching on LUTs and color grading. It was eye opening.

The processor itself doesn't have much to do with it directly, except to provide cpu speed to do the work. That speed, however, can drive the manufacturer to include or exclude functionality, and that can possibly affect quality.

In that regard, using a matrix vs a LUT for the color transform could be affected. A LUT transform requires "more processor" (kinda like, "more cowbell??? ) than a matrix transform.

[Deleted User]

Resurrecting this thread, first in the interest of those who may be using less then perfect AF settings, and secondly to debate whether MFD (i.e. Hasselblad X1D) will produce the effect of more megapixels (i.e. higher acuity) in prints.

After reviewing my D800 and D810 images at 200% with particularly the 24mm F1.8, I felt the lens was not producing expected outputs with landscapes. Good at 100%, deteriorating at 200%. So venturing on the net I found an opinion that one should not use AFC (continuous mode) when using lenses for landscape, but switch to AFS (single). Well after some quick experimentation, I found the difference substantial. Now details are more refined at 200% when using my lenses for landscape.

I had previously defaulted to AFC due to a predominance of bird and wildlife photography with the 200-400 zoom (by the way, you really must use AFC and active VR along with AF fine tuning (I have a +4 setting) with this lens for the best results. The results are stunning with fine very details at 200%). Others knock this lens with D800 and subsequent upgrades.

Second, the test results of the X1DII with various lenses suggests to me a way to print larger than what a 46+MP DSLR will be able to output normally.

Anyone try the Hasselblad and compare it to say a D850?

P.

Pistnbroke

Anything to me with a low pass filter is a waste of space.

tc88

I don't see how AF-C or AF-S makes a difference in landscape. You typically shoot f/8 or smaller openings, and by the nature of landscape, there will be a range of distance anyway. A small focus inaccuracy will just shift the range slightly and should not affect the overall sharpness. Then we are talking about wide angle and it minimize the effect even further. Unless you are shooting at f/2, then it's a different story. My guess which could be wrong, is that the manual switch on either the camera or the lens is accidentally toggled.

[Deleted User]

For almost 7 years I agreed with you which is why I found "the solution" odd. I was going to sell the 24mm because my 28mm was producing sharper landscape enlargements (recent print making).

Having experimented, however, it does seem to me that using AFS does make a noticeable enough difference. Try the experiment yourself and note your own results.

At 200% the 24mm images are materially improved using AFS vs AFC most of the time. So the question with AFC is does focus continue to move even though the subject is stable, and this is causing a slight reduction in acuity. IDK. My shutter speeds are usually less than 1/8 of a second (always on a tripod), so if the camera is shifting to attain focus on AFC while the shutter is moving, is that causing the issue? I am not knowledgeable enough to know. When the shutter is released has the lens changed focus materially to cause the slightly lower acuity? IDK (P.S. I have always used MUP with 2-3 second exposure delay mode and the same tripod for most of my work).

In any event, the new found acuity of the 24 makes it a keeper.

Anyone on use of the Hasselblad?

Pistnbroke

The post is about pixels so if they are hidden behind a low pass filter the sharpness is reduced 20% I think thats relavent .

tc88

@flip, I think it's your lens specific. If the focus changes, you should be able to tell from a sharper area somewhere else since you said the lens is capable of being sharper optically. Rather I think your lens motor may still be whirling even though it's not moving focus, thus causing vibration and reduction of the sharpness.

spraynpray

Pistnbroke said:

Anything to me with a low pass filter is a waste of space.

@flip was comparing lenses and focus settings. The fact that his body has a filter fitted will not change that.

Pistnbroke

The post is about pixels so if they are hidden behind a low pass filter the sharpness is reduced 20% I think thats relavent .

[Deleted User]

You may be correct tc88 in your assessment. I am not sure.

The reference to this issue and recommendations which I have adopted is found in in DP Review threads on the subject.

My point is perhaps I need fewer pixels if my lenses are producing higher acuity due to better practices. If I can produce great prints at 150-200% due to getting the best results from my lenses, then my need for more pixels is perhaps less then I would otherwise expect to need. So with best practices and lenses using good apertures, I may be able to produce 24x36" prints which satisfy. Perhaps 50MPs is enough?

I will continue to experiment.

spraynpray

Pistnbroke said:

The post is about pixels so if they are hidden behind a low pass filter the sharpness is reduced 20% I think thats relavent .

Yes of course. My point was that the same body was used for the comparison so the fact that there is a filter is not relevant.

[Deleted User]

Just an update. The results using AFS with the 24mm are astonishingly better than with AFC - to the point that if Nikon were to come out with a D850 replacement without increasing MPs further, I would likely bite. I would like to see a compliment to the D780 but with at least 45 MPs. Would also like to see silent mode (or as close to silent as possible) using mechanical shutter in other than live view for wildlife. The distortion from electronic shutter with moving subjects is problematic.

As to the Hasselblad, I did some math using PC Magazine's imatest numbers comparing resolution output of a comparable FL lens in 35MM FF 45MP vs X1D at comparable working landscape apertures. The results suggest that other than a higher acuity due to cleanliness of the file with less noise and greater bit depth from the X1D, resolution output is similar, in some cases in favor of FF.

The higher noise from the Sony A7RIV even at lower ISO settings is well established. Whether Nikon feels 60+ MPs can be successfully used in their cameras without an increase in noise at low ISOs is as yet unclear. But one could hope. At this point improved image quality with slightly less saturation in SD profile, greater color accuracy, silent shutter, and a host of benefits from the Z7 with at least 45MPs would be most desirable.

BTW, in performing some careful testing with all of my lenses using AFS for landscape, I found the 28MM improved as well on many images, but also noticed a slight left skew in the lens where top left corner is more OOF then the right at the same aperture. So where I might have used say F11, I am forced to stop down further to compensate for the skew.

I had reached out to Lens Rental a few years back to suggest they might test used (and new) lenses and rate them for proper centering, resolution etc. I guess when they modeled out the costs and what they could charge, it was not feasible.

Perhaps this would be an appropriate business model for WestEndFoto to take on once he purchases an Imatest machine.

More MPs please.

spraynpray

flip said:

More MPs please.

Looks like you will get your wish next year flip.

Photobug

spraynpray said:

Pistnbroke said:

The post is about pixels so if they are hidden behind a low pass filter the sharpness is reduced 20% I think thats relavent .

Yes of course. My point was that the same body was used for the comparison so the fact that there is a filter is not relevant.

Really, I did not know it was 20%. Figured there was some loss of sharpness but had no idea it was that much. Learned something new today, thanks spraynpray.

Photobug

For most amatures the current number of MP is fine. Btu for us advanced a lot of time 24MP is fine but my hunch is that 56 to 60 is really what is needed by pros and some advanced photographers.

I know two wedding photographers and they have been using the D750 for years. Then again, I had a friend in Ohio and one here in Wisconsin that uses the D850 and they told me they need every MP they can get for enlargements.

[Deleted User]

You can always downsample large files to reduce artifacts and improve the output quality. As long as your style is not hindered by buffer limits or slower than needed FPS, and your computer is up to handling the files without freezing, well the more MPs the merrier. If I can get very clean almost noiseless files at ISO 200 and less out of a Nikon ~60MP camera, I would be pleased.

spraynpray

Photobug said:

For most amatures the current number of MP is fine. Btu for us advanced a lot of time 24MP is fine but my hunch is that 56 to 60 is really what is needed by pros and some advanced photographers.

I know two wedding photographers and they have been using the D750 for years. Then again, I had a friend in Ohio and one here in Wisconsin that uses the D850 and they told me they need every MP they can get for enlargements.

I think they are just gearheads justifying their purchases . I have seen one of my D7100 images of a wedding party blown up to 4 feet on the long edge and that was 24mp. My D850 is good for landscape but my D750 was better for general and low light photography. The brilliant AF of the D850 makes it impossible for me to go back though and as I have said before, a 24mp D850 would be buried with me.

Photobug

spraynpray -- I agree that the D750 was better for general and low light photography. Walks all over my D7100. When I sold it last month I felt good in that the lady who bought the D750 knew exactly what she was getting.

Can't wait for a vacation with the D780 and I have got to start playing with the video side of this camera.

Oh, I had one of my D7100 images blown up to 24 inches and framed and hung in a photo store for 2 months for winning a photo contest. Tack sharp. Miss that 17-55 F/2.8 lens. Doesn't surprise me about that 56 to 60 inches.