M9 vs M8 and the effect on bokeh?

Fujitsu

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I´ve seen resolution and "high iso" comparisons of both cameras. What I wonder is, how far the full frame M9 affects bokeh over the M8?

If you have used both cameras, maybe even side by side, please share some examples.
 
yeah, its the same image just cropped on the m8.
the m9 renders a better image @ higher ISO'S - imagine one stop improvement.
the m9 is leaps and bounds a better camera, although it's slower than the m8.

i have 2 m8's (one m8.u one m8.c) for sale -- PM me.
going to put them up tomorrow.

thanks
 
DOF in crop cameras

DOF in crop cameras

In general, you get greater depth-of-field the smaller the sensor/negative, assuming that you are taking the same picture from the same location (so you would be using a 35 mm focal length on the M8 where you would use a 50 mm on the M9).

It is possible to calculate (although I wouldn't be able to) how much more DOF you get with a certain crop. I have heard that you gain 1-2/3 of a stop DOF when you go from full frame to APS-C size (typical dSLR sensor size, roughly half-frame). I understand that to mean that f/2.8 on APS-C will look like close to f/5.6 on FF. The crop factor on the M8 is less than on the APS-C (1.3 vs. 1.6) so the difference will not be as dramatic, but you should definitely expect more DOF with the M8 (less pronounced out-of focus areas) than the M9 for the same aperture.
 
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On modern lenses it is much of a muchness, with older, high-aberration lenses the M9 shows more of the bokeh character one would expect on film. The cause is the cutting off of the edge rays by the M8 due to the crop.
 
If you shoot with the same lens from the same distance, bokeh should be the same.

You will see different amount of bokeh ONLY WHEN you try to frame the same, which you need to either shoot closer with the same lens with M9 or shoot with longer lens from the same distance.
 
.) same lens, same distance, different crop: M8 has less DOF
.) same distance, same FOV/crop, different focal length: M8 has more DOF

As for the digital vs. film impact on bokeh, I always felt there was something but cann't put my finger on it.
 
.) same lens, same distance, different crop: M8 has less DOF
.) same distance, same FOV/crop, different focal length: M8 has more DOF

As for the digital vs. film impact on bokeh, I always felt there was something but cann't put my finger on it.
I can (put my finger on it) Film has a thickness, causing diffraction, refraction, etc and thus creates a much gentler DOF gradient than a sensor which is a plane without any (well, nearly) thickness. The difference is like shining a torch into a murky bowl of soup vs a flat surface. Thus bokeh on a sensor is much more defined. Some would call it harsh.
 
.) same lens, same distance, different crop: M8 has less DOF

I don´t think so. If you also mean same aperture, the M8 has the same DOF with the same lens (= same focal lenght) and distance. The FOV is smaller, because you use only a smaller part of the screening by cropping, but the characteristis of the lens are not changed.

.) same distance, same FOV/crop, different focal length: M8 has more DOF

I agree because, as you are writing, the different focal lenght.
 
In general, you get greater depth-of-field the smaller the sensor/negative, assuming that you are taking the same picture from the same location (so you would be using a 35 mm focal length on the M8 where you would use a 50 mm on the M9).

It is possible to calculate (although I wouldn't be able to) how much more DOF you get with a certain crop. I have heard that you gain 1-2/3 of a stop DOF when you go from full frame to APS-C size (typical dSLR sensor size, roughly half-frame). I understand that to mean that f/2.8 on APS-C will look like close to f/5.6 on FF. The crop factor on the M8 is less than on the APS-C (1.3 vs. 1.6) so the difference will not be as dramatic, but you should definitely expect more DOF with the M8 (less pronounced out-of focus areas) than the M9 for the same aperture.

Thanks, that´s very helpful. And it is one reason for me to stay with crop 1,3 to get some more sharpness with wide open lenses. It is not that easy to get the right focus at low light.
 
generally speaking, there will be slightly less dof, and the lenses you use for a given angle of view on either camera will make the biggest difference.
 
A 50mm lens has exactly the same DOF on either camera at the same focusing distance; however, the crop camera will more tightly frame the subject, so for equal framing you will have more DoF because the distance from the subject will have to increase. This is easy to understand. Why is there so much BS in here?
 
A 50mm lens has exactly the same DOF on either camera at the same focusing distance; ... This is easy to understand. Why is there so much BS in here?

No.

DOF is defined via a given print size and viewing distance. It's a simple concept with lots of literature around.

I repeat, for the same lens, same aperture and focus distance (i.e., different FOV) the M8 will have less DOF than the M9; To get the same final print size, the M8 image has to be enlarged more than the M9 image. The DOF scale on the lens will be correct for M9 but not for M8. A 90/2 Summicron or 50mm Noctilux is harder to focus on M8 than on M9.

Check dofmaster.com, and M8 and 35mm film COC definitions.
 
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Print size and circle of confusion

Print size and circle of confusion

Ferider, I agree that it is overly simplistic to not consider the effect of negative size (sensor size) relative to print size, but I believe your statement

"same lens, same distance, different crop: M8 has less DOF"

makes one assumption, namely that those crops will be printed at the same size. If, on the other hand, you print the M8 and M9 at sizes proportional to their sensor size (the M9 print being bigger than the M8), wouldn't the part of scene visible on the M8 print look more or less exactly as the same part of the M9 print in terms of DOF, bokeh?

If someone had a hard time focusing a 50 mm lens on an M9 in low light, wouldn't he/she be better off with a 35 mm on an M8?

What print size and viewing distance are the DOF markings on a lens traditionally based on?

Thanks.
 
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No.

DOF is defined via a given print size and viewing distance. It's a simple concept with lots of literature around.

I repeat, for the same lens, same aperture and focus distance (i.e., different FOV) the M8 will have less DOF than the M9; To get the same final print size, the M8 image has to be enlarged more than the M9 image. The DOF scale on the lens will be correct for M9 but not for M8. A 90/2 Summicron or 50mm Noctilux is harder to focus on M8 than on M9.

Check dofmaster.com, and M8 and 35mm film COC definitions.

You are wrong. 100% wrong. The M8 will never have less DoF at a given distance than a full-frame camera.
 
... I believe your statement

"same lens, same distance, different crop: M8 has less DOF"

makes one assumption, namely that those crops will be printed at the same size. If, on the other hand, you print the M8 and M9 at sizes proportional to their sensor size (the M9 print being bigger than the M8), wouldn't the part of scene visible on the M8 print look more or less exactly as the same part of the M9 print in terms of DOF, bokeh?

If someone had a hard time focusing a 50 mm lens on an M9 in low light, wouldn't he/she be better off with a 35 mm on an M8?

What print size and viewing distance are the DOF markings on a lens traditionally based on?

Thanks.

Agree on all your points.

Usually it's 8x10 print size view'ed from 1 foot. See for example http://www.cambridgeincolour.com/tutorials/depth-of-field.htm.

Best,

Roland.
 
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