Page 1 of 2 12 LastLast
Results 1 to 10 of 12

Thread: information on miniumum distance for LF lens???

  1. #1
    stradibarrius stradibarrius's Avatar
    Join Date
    Feb 2011
    Location
    Monroe, GA
    Posts
    818

    information on miniumum distance for LF lens???

    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...

  2. #2
    William Whitaker's Avatar
    Join Date
    May 2002
    Location
    The Southern Part of Heaven
    Posts
    1,265

    Re: information on miniumum distance for LF lens???

    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!!

  3. #3
    ic-racer's Avatar
    Join Date
    Feb 2007
    Posts
    5,285

    Re: information on miniumum distance for LF lens???

    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.)
    Click image for larger version. 

Name:	Nikkor.jpg 
Views:	27 
Size:	75.6 KB 
ID:	123132

  4. #4
    stradibarrius stradibarrius's Avatar
    Join Date
    Feb 2011
    Location
    Monroe, GA
    Posts
    818

    Re: information on miniumum distance for LF lens???

    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...

  5. #5

    Join Date
    Dec 2001
    Location
    NJ
    Posts
    7,437

    Re: information on miniumum distance for LF lens???

    Barry, the answer you need is in this http://www.largeformatphotography.in...crophotography recent discussion.

  6. #6

    Join Date
    Sep 1998
    Location
    GA
    Posts
    12,380

    Re: information on miniumum distance for LF lens???

    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.

  7. #7

    Join Date
    Feb 2001
    Location
    Los Angeles
    Posts
    2,235

    Re: information on miniumum distance for LF lens???

    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.

  8. #8
    ic-racer's Avatar
    Join Date
    Feb 2007
    Posts
    5,285

    Re: information on miniumum distance for LF lens???

    Quote Originally Posted by stradibarrius View Post
    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.

  9. #9

    Join Date
    Dec 2001
    Location
    NJ
    Posts
    7,437

    Re: information on miniumum distance for LF lens???

    ic, see post #5

  10. #10
    William Whitaker's Avatar
    Join Date
    May 2002
    Location
    The Southern Part of Heaven
    Posts
    1,265

    Re: information on miniumum distance for LF lens???

    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.

Similar Threads

  1. Distance lens to film plane
    By cyron123 in forum Lenses & Lens Accessories
    Replies: 2
    Last Post: 14-May-2014, 00:55
  2. Lens to Film Distance for 180mm?
    By Garry Madlung in forum Lenses & Lens Accessories
    Replies: 27
    Last Post: 11-Apr-2009, 00:39
  3. lens focus distance
    By swmcl in forum Lenses & Lens Accessories
    Replies: 7
    Last Post: 3-Dec-2006, 16:18
  4. Enlarging lens to paper distance
    By Dan Fromm in forum Darkroom: Equipment
    Replies: 1
    Last Post: 30-Nov-2003, 17:24
  5. Horseman 45FA Lens Distance Scale
    By d.s. in forum Lenses & Lens Accessories
    Replies: 5
    Last Post: 9-Dec-2001, 06:09

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •