New to MF - have a few ?'s

[compur]

I fully agree that in the real world one usually gets less DOF shooting MF vs 35mm and I said so in my first post.

I also said that the same focal length and same enlargement results in the same DOF and gave a reference to back up that statement.

I don't know what the big argument is about. If one disagrees with my reference then complain to the wikipedia. It says what it says and I didn't write it.

You first said; "DOF is determined by lens focal length and aperture regardless of film format." That's incorrect.

No, it isn't as long as the degree of enlargement is the same and I gave a reference to back that up.

Folks who shoot medium format cameras don't process their film and then only make prints enlarged to the same degree as if they had shot 35mm film. They don't take a pair of scissors and cut out 35mm sections from their 120 negs to print from.

Maybe you are confused by "same degree of enlargement"? It just means if you enlarge by say 4:1 then you'd get a 4x6 print from a 35mm negative or roughly a 9x11 (8x10 in the real world) print from a 6x7cm negative. I don't think either of these print sizes are unusual or "not what folks who shoot medium format do." I have made many 4x6 prints from 35mm negatives and many 8x10s and 11x14s from 6x7 negatives. What is so "not-real-world" about making prints in these sizes?

 

[Ysarex]

I fully agree that in the real world one usually gets less DOF shooting MF vs 35mm and I said so in my first post.

And you went on to qualify that statement in that same sentence: "However medium format cameras do tend to use longer lenses than 35mm cameras so in that sense you will tend to have shallower DOF with a MF camera but it's not the film format that is causing it." The film format is in part causing a DOF difference and you could possibly slide by with this statement except that you said in the previous sentence: "DOF is determined by lens focal length and aperture regardless of film format." That's wrong. Film format is a DOF determinant factor. You're first post is incorrect -- obviously proven so by the illustrations I posted.

I also said that the same focal length and same enlargement results in the same DOF and gave a reference to back up that statement.

No you did not. You're use of "also" in this sentence is a trumpian attempt to imply you said that in your first post. Here's your entire first post:

"DOF is determined by lens focal length and aperture regardless of film format. However medium format cameras do tend to use longer lenses than 35mm cameras so in that sense you will tend to have shallower DOF with a MF camera but it's not the film format that is causing it. In other words, if focal length and aperture are the same on a 35mm vs MF camera then the DOF will also be the same with both."

There is no mention in your first post of enlargement. In fact your 3rd and final sentence drives home the initial error. If focal length and aperture are the same on a 35mm vs MF camera the DOF will NOT be the same with both. You mentioned enlargement in your 2nd post after I pointed out your first post was incorrect. Your first post still stands as incorrect and the condition of "same enlargement" is simply a way of removing the variation of format size from the equation and is completely lame.

If you're going to do a comparison of DOF between cameras with different formats the only valid comparison that makes sense is to take the same photo with both. That will necessitate different degrees of enlargement (which is also pointed out in the Wiki article you referenced) and the difference in DOF that will occur will be in part due to the difference in the film formats.

Joe

 

[compur]

This has just gotten too ridiculous to continue. I advise others, if they are interested, to simply read the wikipedia page on Depth of Field which I happen to agree with but don't really care enough to argue about.

Joe, you may now carry on enlightening the world with your superior knowledge of all things photographic without further interruption from me.

 

[Ysarex]

This has just gotten too ridiculous to continue. I advise others, if they are interested, to simply read the wikipedia page on Depth of Field which I happen to agree with but don't really care enough to argue about.

No argument from me over the Wiki article -- good source.

Joe

Joe, you may now carry on enlightening the world with your superior knowledge of all things photographic without further interruption from me.