I have googled trying to find information on minimum focal distance on LF lenses. for example a fujinon-w 150mm...
What factors effect the ability to focus up close?
If I wanted to fill the frame with Rose is is better to use a longer focal length? The closer you want to focus the more bellows travel is needed, is that correct.
Generalizations are made because they are Generally true...
Bellows extension is your limiting factor. Yes, the closer the lens-subject distance, the more bellows is required.
Is Rose a flower or a person? If the latter, you won't be doing her any favors by using a shorter FL lens. The resulting perspective would be less than flattering. Other than that, optically, I doubt if it makes any difference, but I can't substantiate that statement.
Don't forget bellows factor when you determine exposure!!
MTF curves for non-macro lenses are usually done at 'infinity' but you can expect the field to curve more and more the closer you get.
Lenses that are designed for close up work do indeed come with specs on minimum useful distance (encoded as 'magnification' in this chart.)
I probably didn't ask the question correctly. Example; if I extend the bellows fully and find I have to either back up or partially retract the bellows then the limitation is the lens and not the length of the bellows...correct???
Generalizations are made because they are Generally true...
Barry, the answer you need is in this http://www.largeformatphotography.in...crophotography recent discussion.
General purpose lenses are optimized usually for 1:20 and some, like the Apo SIronar-S for 1:10. These lenses, including your Fujinon, are not corrected for macro.
If you extend the bellows fully and cannot get 'close enough' to the subject, nothing is wrong with the lens. You need a longer bellows.
If you find you have to shorten the bellows to get the size image you want (I assume you mean this by "partially retract the bellows") then everything is fine; you have plenty of bellows and more extension than you need. Nothing is wrong with the lens. Only you can decide if macro results from a general purpose lens are adequate for your purposes.
As somebody said earlier, make sure you understand that you will need extra exposure for such close ups.
In that case you can approximate with 1/p + 1/q = 1/f where p = subject to lens and q is lens to film and f is focal length.Originally Posted by stradibarrius
ic, see post #5
One of our venerable moderators has this page on his site which you may or may not find helpful as the original question is about as clear as mud now.
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