Yet another M8 DOF internet myth busted

[ampguy]

First photo is with my M6, 2nd two photos are with M8. Both are using the same 35/1.4 pre-asph lux at f8, and both are at 1/30th. Both are on the stationary tripod (note that the M8 has tripod threads under the center, M6 has tripod mount on side).

Focus for the first two images is on the "Scotch" tape wording on the tape on the white comforter, 6 feet away.

Focus for the 3rd image, or 2nd M8 image, focus barrel was moved exactly 1 stop on the DOF markings towards wider open, further focus of about 7 ft.

This author found no improved benefits for the DOF barrel move, to match the DOF of the film image.

Conclusion? Internet Myth Busted. Leica is correct in that no lens adjustment is needed with 35mm M-mount lens on the M8, in order to equal DOF of M FF systems.

results are here

 

[henningw]

It really depends on your shooting parameters and what you are trying to do. Is a consistent angle of view important (your shots don't show that) or a consistent perspective (your shots do show that).

If the same angle of view and same perspective are required, dof differences arise.

All this is assuming the final image will be enlarged to the same size with no cropping. If that's not the case, things change again.

In any case, the baseline parameters have to be stated in full, otherwise a conclusion is impossible.

Henning

 

[Brian S]

I agree completely, the DOF marks are equally valid for the M8 as they are for a 35mm camera.

And I could quote Rudolf Kingslake on this forum too....

DOF marks are guides, indicators, with a set of assumptions made about viewing the image and the medium that the image is recorded with. "Mental grains of Salt" should be used. Get to know a lens and how it performs at each F-Stop, and how you plan to present the final image.

 

[jaapv]

I like this approach. Quite refreshing

http://www.trenholm.org/hmmerk/DOFR.html

 

[ampguy]

Thanks Henning, Brian and Jappv.

Yes Jappv, that guy's idea of shooting at infinity always does make some sense, and it is interesting that I believe he wrote all that even before digital, but as films were getting better.

But if you've got close up subjects, you do need to focus.

On the Hexar AF, which has a dedicated infinity focus button, I do hit that if my subjects are past about 15 meters, and I believe all ~200+ focus steps on the Hexar are all within the .5-20m range, then past then all is at infinity focus.

 

[jaapv]

Indeed he is not alone. I still remember Gunther Osterloh telling me with emphasis: "If you want something sharp, focus on it!" He does not believe in hyperfocal either.

 

[ampguy]

Haha, well I don't know Mr. Osterloh, but after reading his book a few times, and making a hefty profit on selling it, it's hard to believe him saying anything about RF photography without trying to sell you something

Indeed he is not alone. I still remember Gunther Osterloh telling me with emphasis: "If you want something sharp, focus on it!" He does not believe in hyperfocal either.

 

[jaapv]

Gunther has never been in the selling line. His forte is teaching.