Comparison of DOF for an Olympus OM Zuiko 50mm f/1.2 lens on a Canon 10D dSLR

[Neil]

... part 1,

From top to bottom: f/1.2, f/2, f/2.8, f/4

[Neil]

... part 2,

From top to bottom: f/5.6, f/8, f/11, f/16

[mikaelwardhana]

wait a minute...this is from an OM zuiko lens...but mounted on a 10D canon.... how did you do this?
very curious mode = ON..

[Neil]

Originally Posted by mikaelwardhana

wait a minute...this is from an OM zuiko lens...but mounted on a 10D canon.... how did you do this?
very curious mode = ON..

No great mystery here - I have an OM-EF adapter. It's about 2mm thick, goes on the EOS camera, and the OM lenses go on the adapter.

Originally Posted by Pavel

Neil, I would be interested to see some kind of comparison with the same lens on a E-1 or E-300 to see what the difference would be like if the image size was adjusted for so that the subject was kept at the same size. Any ideas how we could set that up to do a comparison from across the US? Perhaps to include a ruler in the shot and a identical scene made up of carefully placed common objects? It would help answer and illustrate the dof thing with the ( I know I'm going to get taken to task for this wording ) crop difference between 1.6 and 2. I'd be curious.

I don't have (or have access to) either the E-1 or E-300 (but donations will be appreciated!!). I'll think about your idea, and if I come up with any thoughts, I'll post back here.

Originally Posted by Pavel

It's interesting to note the difference in contrast and color between the sets of shots ... I pressume it must be in the editing of the shots, right?

Guilty as charged - I was using auto exposure (this was a mistake, although I didn't expect it to have so much effect!!) for each f-stop. I have not adjusted the colours, but the sun was quite low in the sky at the time (I had actually shut the door on the sunlight, but enough of a change must have got through to affect the colour). I do confess to adjusting the brightness - guilty as charged!! but the photos were really different in brightness!
Why didn't I wait until another time to do it? I'd already promised this days ago and decided to do it then as a spare moment had finally come up. I admit the comparison is flawed, but not with the DOF at least...

Thanks all who had an interest!

[Neil]

Originally Posted by Pavel

Neil, I would be interested to see some kind of comparison with the same lens on a E-1 or E-300 to see what the difference would be like if the image size was adjusted for so that the subject was kept at the same size. Any ideas how we could set that up to do a comparison from across the US? Perhaps to include a ruler in the shot and a identical scene made up of carefully placed common objects? It would help answer and illustrate the dof thing with the ( I know I'm going to get taken to task for this wording ) crop difference between 1.6 and 2. I'd be curious.

Hi Pavel,
I think you are right - a ruler in the photo would work, and probably it would be best to agree on a distance that the ruler should be from the camera. Say perhaps have the ruler at 2 feet (ie. set the lens to focus at 2 feet, and move the ruler until it is in sharp focus). Or the ruler could be at any distance, but this should probably be agreed upon first and everyone sticks to this distance.
I'm not sure what common objects - and I mean truly common objects here - could be used for this; within one country, coins could be used I guess... but here in Australia I do not have any U.S. coins handy!!