information on miniumum distance for LF lens???

[stradibarrius]

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.

[William Whitaker]

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!!

[ic-racer]

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.)
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[stradibarrius]

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???

[Dan Fromm]

Barry, the answer you need is in this http://www.largeformatphotography.info/forum/showthread.php?117048-Enlarger-lenses-for-Large-Format-Macrophotography recent discussion.

[Bob Salomon]

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.

[Kevin Crisp]

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.

[ic-racer]

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???

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.

[Dan Fromm]

ic, see post #5

[William Whitaker]

One of our venerable moderators has this page (http://www.kenleegallery.com/html/tech/bellows.php) on his site which you may or may not find helpful as the original question is about as clear as mud now.

[Tin Can]

I admire Mr Lee's generosity of providing a valuable website, but that link and it's mostly metric sizing gives me a conversion headache. I can convert metric to US pretty darn good, but wow, I wish he had included the same thing done in inches.

Not trying to be a USA Luddite, but many of my lenses and formats are already described in inches. Gross estimation of bellows factors by full inches is much faster to internalize and utilize than in millimeters.

My 210 mm lens is actually marked 8-1/4 and I simply call it 8". Mr Lee does use the simple conversion of 8" to 200 mm, but after that...

Not trying to obfuscate or complain about Mr Lee's FREE site, simply observing a possible difficulty in utilization.

[StoneNYC]

I admire Mr Lee's generosity of providing a valuable website, but that link and it's mostly metric sizing gives me a conversion headache. I can convert metric to US pretty darn good, but wow, I wish he had included the same thing done in inches.

Not trying to be a USA Luddite, but many of my lenses and formats are already described in inches. Gross estimation of bellows factors by full inches is much faster to internalize and utilize than in millimeters.

My 210 mm lens is actually marked 8-1/4 and I simply call it 8". Mr Lee does use the simple conversion of 8" to 200 mm, but after that...

Not trying to obfuscate or complain about Mr Lee's FREE site, simply observing a possible difficulty in utilization.

I'm an American and I HATE the very luddite us measure system, it's ridiculous...

4 of something equals 12 of something else that equals 16 of something else? And fractions (a division equation) as a number? Ridiculous!!!

Also, just do all calculations in metric and take the final result and convert it don't try and convert every step.

Good luck!

Also, OP, there's an app for this called the "reciprocity timer" app on iPhones, if you have that, I highly recommend at LEAST getting the basic version, I think it's $3? Totally worth it!!! And it will adjust for your long bellows.