Is the 5D Mark III Sharp??

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dilbert said:
There's no such thing as a sharp or soft DSLR.

Really? Then why is Nikon selling both a D800 and a D800E? Isn't one of those sharper than the other? By extension, doesn't it stand to reason that the properties of the anti-aliasing filter determine the 'sharpness' of the dSLR, and that's one of the design decisions that a manufacturer makes?

Canon has stated that the 5DIII offers improved video characteristics, in particular they mention a reduction in moiré. I'd argue that the easiest way to reduce video moiré is to use a 'stronger' AA filter. One of the trade-offs in doing so is reduced sharpness.

Worth noting is the person who took apart his 5DIII and removed the AA filter, in particular the statement, "It does seem like a particularly strong optical low pass filter on this camera... OLPF, AA, anti-aliasing filter, call it what you will – it seems Canon put too strong a one in the 5D Mark III! Yes it crushes moire but the trade off is less resolution not just in video mode, but also for stills." You can see examples on the linked page.
 
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dilbert said:
Readout noise does not affect sharpness, it affects the SNR.
SNR is a relevant factor to sharpness, taking that to mean (fine) contrast resolving power. Readout noise can reduce the SNR and thereby the resolving power of the signal. Which does in the extremes affect sharpness (though probably not on ISO 100 images taken in controlled studio conditions. But you were saying that there was no influence on sharpness whatsoever, and that's just wrong.)

The area covered by the microlens/pixel will not affect sharpness, it will affect light gathering ability.
I was thinking about that. I was not entirely sure. However, I figured that it'd have an effect in more smoothly rendering small detail, when the pixel is a full square rather than when it is a tiny hole covered with non-light-gathering gaps in between (to take an extreme example). Obviously, light gathering ability is the major difference, and a sharpness increase will be tiny. But I'm tending to think that there will be SOME effect.
Compare a grid of small circles (the circles being light sensitive, the area in between the circles not) and a grid of squares (100% coverage pixels) and compare their resolving power. The grid of small circles will miss some light (coverage), which will in most situations also include contrast differences (which equals detail). Cropping out contrast differences can't have a positive effect on sharpness, I'd think.

Sensor well leakage only happens when a pixel has too much light in it.
I thought its effects became more significant as the wells filled up (perhaps exponentially so), but that it is still present below the threshold of a completely "full" well. If you're correct, then it indeed has no impact on sharpness or contrast resolving ability.

Whether the above are or are not possible factors, that still leaves the AA filter as well, of course.
 
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neuroanatomist said:
dilbert said:
There's no such thing as a sharp or soft DSLR.

Really? Then why is Nikon selling both a D800 and a D800E? Isn't one of those sharper than the other? By extension, doesn't it stand to reason that the properties of the anti-aliasing filter determine the 'sharpness' of the dSLR, and that's one of the design decisions that a manufacturer makes?

Canon has stated that the 5DIII offers improved video characteristics, in particular they mention a reduction in moiré. I'd argue that the easiest way to reduce video moiré is to use a 'stronger' AA filter. One of the trade-offs in doing so is reduced sharpness.

Worth noting is the person who took apart his 5DIII and removed the AA filter, in particular the statement, "It does seem like a particularly strong optical low pass filter on this camera... OLPF, AA, anti-aliasing filter, call it what you will – it seems Canon put too strong a one in the 5D Mark III! Yes it crushes moire but the trade off is less resolution not just in video mode, but also for stills." You can see examples on the linked page.
funny you mention that!
I was painstakingly analysing my $50 note shots of 5D3 vs 5D2 again at 200% and you can distinctly see moire pop up in the 5D2 shots (which also happen to appear to be sharper than the 5D3 to me at this magnification)
the 5D3 shot dont seem to have the moire issue.
Although all this is observed at 200% magnification it really has a miniscule impact on the overall image.
Disclaimer : I dont go through puiles of pictures at 200% for fun, just trying to get to the bottom of my twightlight zone AF issues i'm having :(
 
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What´s wrong with my replies? I tried twice to reply to this topic including two jpg-files, one of them showing, that the 5D III is sharp, but nothing appears here?

What is my mistake?
 
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dilbert said:
If you shoot raw then the camera is neither sharp nor soft.

A lens can be soft if its focus alignment does not match up with the camera (see discussions on micro-focus adjust).

A JPEG can be soft if the conversion algorithm is not up to scratch.

That's it.

There's no such thing as a sharp or soft DSLR.

I would disagree... my rebel XT (8mp ) is way sharper than the 1d mk.ii I had (8mp).. I attribute that to the aggressive AA filter on the 1d2. So yes you can have a sharp and soft DSLR just like the D800 is a softer version of the D800E.
 
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risc32 said:
I happen to of taken very similar photos of my dog the other day with my mk3. i used my 70-200 2.8, not sure right now about the exact values, but the focus was spot on. I think it's pretty good when you can make out your house in the reflection of an eye. When i get to my computer i'll try and post one.

Correct, the hair around the eye looks soft, but the veins in the eye and the reflection is very sharp... tells me you shot wide open and the shallow DoF caused the hair to look soft.
 
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JohnX said:
Here's another sample hand held in dim light

Lens: EF 24-105mm f/4L IS
ISO: 2000
Focal Length: 105mm
Aperture: f/4.5
Shutter: 1/40s

6892432752_4041a50fd6_b.jpg

You got only one figure in focus... rest are so soft. :P
 
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