Page 1 of 3 123 LastLast
Results 1 to 10 of 24

Thread: Help Toyo View D45M Focus problems

  1. #1

    Join Date
    Nov 2018
    Location
    Northern California
    Posts
    32

    Help Toyo View D45M Focus problems

    Hello all,
    I am new to LF photograhy but have been taking and printing my own photos for quite a few years. I recently purchased a Toyo D45M. The problem I am having is that the focus is shifted, I focus on an object and on the GG it looks great, but when I look at my negatives what I focused on is soft and things a few feet back from it are very sharp. I have checked the fresnel lens and GG and it looks like it is installed correctly from info I found online from Toyo. This model camera seems to have come with the fresnel lens installed from the factory, all the D45m's I see have one. What could be the problem, I am at a loss? Any help is appreciated.

  2. #2
    Tin Can's Avatar
    Join Date
    Dec 2011
    Posts
    13,559

    Re: Help Toyo View D45M Focus problems

    Consider 5 things.
    Format
    Lens FL
    Where to focus
    DOF desired
    Aperture desired

    This free tool is useful

    http://www.dofmaster.com/dofjs.html

    After that you have movements.
    sin eater

  3. #3

    Join Date
    Nov 2018
    Location
    Northern California
    Posts
    32

    Re: Help Toyo View D45M Focus problems

    I know where I am focusing and about DOF etc. the focus is never on the object I focus on for example a still life of a camera on a shelf, the camera turns out soft and and behind it is sharp. Thank you for the link that tool looks very useful, I will try some of the suggestions there.

  4. #4
    Tin Can's Avatar
    Join Date
    Dec 2011
    Posts
    13,559

    Re: Help Toyo View D45M Focus problems

    sin eater

  5. #5
    Maris Rusis's Avatar
    Join Date
    May 2006
    Location
    Noosa, Australia.
    Posts
    1,067

    Re: Help Toyo View D45M Focus problems

    If the focus you get on the film is clear for objects further away that the ones you focussed on in camera then the film is closer to the lens than the ground surface of your ground-glass. Two initial possibilities:

    The ground-glass might require a fresnel between it and the camera lens. The effect of a fresnel is to shorten the optical distance between the ground-glass and camera lens. If the camera was designed to incorporate such a fresnel and it is missing then the ground-glass is too far from the camera lens and you will get the back-focussing problem you see.

    The ground-glass may be in backwards with the ground surface facing away from the camera lens. The size of the focus position error is the thickness of the ground glass and again back-focussing is the unfortunate result.
    Photography:first utterance. Sir John Herschel, 14 March 1839 at the Royal Society. "...Photography or the application of the Chemical rays of light to the purpose of pictorial representation,..".

  6. #6

    Join Date
    Nov 2018
    Location
    Northern California
    Posts
    32

    Re: Help Toyo View D45M Focus problems

    Actually the camera has a official Toyo fresnel lens and a ground glass, it came this way from Toyo and everything is installed correctly. the fresnel lens is in front of the GG and everything is facing the proper way. it's a mystery.

  7. #7
    ic-racer's Avatar
    Join Date
    Feb 2007
    Posts
    5,507

    Re: Help Toyo View D45M Focus problems

    Since the subject in focus is behind where the ground glass shows, the film is closer to the lens than expected. Rather than moving the film back, try moving the ground glass forward. For example, see what happens when the fresnel lens is removed and the ground glass is moved forward.

  8. #8
    Arca-Swiss
    Join Date
    May 2002
    Location
    Phoenix, AZ
    Posts
    124

    Re: Help Toyo View D45M Focus problems

    As people have suggested the addition of glass or fresnel, and even filters will move the focus 1/3 the thickness of the added glass.

    My suspicion is the fresnel is reversed. The smooth side of the fresnel should be on the lens side and also the ground side of the glass is also correctly placed when the rough or ground side faces the glass.

    In terms of a focus aid, if you use one, it should not be higher than 5x in magnification. If higher it begins to magnify the pattern of the GG or even the rings of the fresnel. *x and higher are definitely not good. The Hoodman loops for LCD screens are good at 2-3x.

    Finally check the rear group of the lens is crewed all the way into the lens. We focus wide open as is correct. But when we stop down the lens the Red wave lengths move forward and cause softening of the image. This may be somewhat covered by stopping the lens down as can be done with film photography. For normal lenses 135mm and longer you should always stop down at least 2 stops for best quality. For wide angles as this red movement is worse, 3 stops are called for.

    Hopefully this may be of help for you.
    Rod Klukas
    US Representative
    Arca-Swiss International
    480-755-3364


    Digital Camera Solutions including R-series Technical Cameras, Large Format View Cameras and Ballheads. 480-755-3364

  9. #9

    Join Date
    Nov 2018
    Location
    Northern California
    Posts
    32

    Re: Help Toyo View D45M Focus problems

    Now that I'm home I see how it fits together, the fresnel lens is held in by clips and it is smaller than 4x5, so even though the GG is sandwitched with it the fresnel lens does not effect the spacing of the GG, the GG is flush like it should be with or without the fresnel, the GG still sits in the same place. So I will try some focus tests tonight.

  10. #10

    Join Date
    Nov 2018
    Location
    Northern California
    Posts
    32

    Re: Help Toyo View D45M Focus problems

    I'm positive nothing is reversed or put in backwards, it is all facing the correct direction. Yes the fresnel has the shiny side facing the lens like Toyo states.

Similar Threads

  1. Toyo-View Deuxe 45M Rail Problems
    By gentlegiant1972 in forum Cameras & Camera Accessories
    Replies: 3
    Last Post: 13-Apr-2018, 16:20
  2. Toyo View D45M tripod bush size
    By brucep in forum Cameras & Camera Accessories
    Replies: 3
    Last Post: 17-Jul-2012, 18:04
  3. Toyo view d45m - any spare parts?
    By jvuokko in forum Cameras & Camera Accessories
    Replies: 8
    Last Post: 27-Nov-2009, 09:53
  4. Toyo D45M mania?
    By John C Murphy in forum Cameras & Camera Accessories
    Replies: 3
    Last Post: 29-Apr-2005, 07:50

Tags for this Thread

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
  •