Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 71,957   Posts: 1,586,049   Online: 788
      
Results 1 to 10 of 10
  1. #1
    blackmelas's Avatar
    Join Date
    Aug 2004
    Location
    Corinth, Greece
    Shooter
    35mm RF
    Posts
    353
    Images
    24

    Omega D-3 vignetting problem

    Recently I noticed significant corner vignetting while printing 4x5 full-frame with a 135mm lens. The D-3 has a variable condenser housing with three slots for the upper condenser lens: the upper slot for 50-80mm, middle for 90-105mm, lower for 135mm, and removing the condenser lens for 150-165mm. When the vignetting was noticed naturally the lens was in its proper place in the lower slot. However when I removed the condenser lens altogether the vignetting disappeared. Will I be compromising sharpness significantly by printing without the condenser lens and a 135? Should I spring for a 150mm lens for better coverage of the negative?
    Thanks for your advice,
    James

  2. #2

    Join Date
    Dec 2004
    Shooter
    Multi Format
    Posts
    2,146
    I don't know in how much the D3 resembles the DII, but I noticed the same when I started using the DII.
    The problem was solved when I completely lowered the condensor house onto the negative carrier, using a 150mm lens.

    G

  3. #3

    Join Date
    Aug 2003
    Location
    sao paulo - brazil
    Posts
    127
    Ask Harry, who knows everything about it.
    www.classic-enlargers.com
    sergio caetano

  4. #4

    Join Date
    Dec 2003
    Location
    memphis
    Shooter
    4x5 Format
    Posts
    60
    I used a D-3 for several years with a 150mm lens and didn't have a problems. I never used a 135mm on this enlarger so I can't comment directly to your problem. As Sergio stated above, contact Harry at classic enlargers. He made my 150mm focus track and told me how much to extend a 135mm cone where I could use a 150mm lens.
    Ron
    Memphis

  5. #5

    Join Date
    Dec 2004
    Shooter
    ULarge Format
    Posts
    194
    I had the same problem with my D2 and a 135 mm. The same problem also appears when using a 80 mm and the condensor in the upper slot. So, now i print without a condensor when using a 135 mm, and with the condensor in the middle slot when using a 80 mm. Never noticed a loss of sharpness with this construction, but i didn't do any comparative testing. Someone may correct me, but my understanding is that the condensors are meant to provide an even illumination of the negative and have no direct influence on the sharpness of the print.

    Huub

  6. #6

    Join Date
    Jan 2005
    Location
    Downers Grove Illinois
    Posts
    1,053
    I have an original D2, not the variable, with all three condenser sets.

    The 6+in condensers work fine with both 135 and 150 lenses on the proper cones. The condensers are as close together as possible flat sides out, convex sides nearly touching.

    I think you are using the wrong bulb. The PH111 &112 have a long neck compared to other bulbs. A shorter neck like a household bulb has will have the light source improperly positioned, ie too high up, thus causing the vignetting.

    Most 135 lenses will cover 4x5 minimally. My Schneider Comparon 4.5 works perfectly from 8x10 to 20x24. The 150 Comparon was moved to the D6 Chromega for color work, but was fine for the D2.

  7. #7

    Join Date
    Jan 2005
    Location
    Downers Grove Illinois
    Posts
    1,053
    steve swinehart , jul 06, 2005; 11:55 a.m.
    D2-V (variable condenser) head. I bought my D2-V enlarger in 1973. The variable portion of the condenser head is a movable 3rd condenser lens above the two main condensers. The correct positions of the condenser for the film formats are printed on the inside of the door to the variable condenser compartment.


    The above makes more sense to me than removal of the top large condenser. you are likely to be missing the third condenser.

  8. #8
    blackmelas's Avatar
    Join Date
    Aug 2004
    Location
    Corinth, Greece
    Shooter
    35mm RF
    Posts
    353
    Images
    24
    Quote Originally Posted by Ronald Moravec
    I think you are using the wrong bulb. The PH111 &112 have a long neck compared to other bulbs. A shorter neck like a household bulb has will have the light source improperly positioned, ie too high up, thus causing the vignetting.
    This is a possibility. I ordered PH111 or 112 bulds from a US source forgetting about the 220v here-- knocked out a circuitbreaker altogether. So I just bought whatever bulb my shop in Athens had. Perhaps I need to try harder to find those bulbs.

    Do European or Apuggers have an online source for enlarger bulbs? Or Greek Appuggers a source in Athens?

    Thanks for the help,
    James

  9. #9
    Jim Noel's Avatar
    Join Date
    Mar 2005
    Shooter
    Large Format
    Posts
    1,909
    Blog Entries
    1
    IN our college labe we always have students remove the condenser from the Omega enlargers when printing 4x5 negatives. SInce the diameter of the condenser is barely as long as the diagonal of the film, this is the only way we have found to eliminate the vignetting.
    [FONT=Comic Sans MS]Films NOT Dead - Just getting fixed![/FONT]

  10. #10
    blackmelas's Avatar
    Join Date
    Aug 2004
    Location
    Corinth, Greece
    Shooter
    35mm RF
    Posts
    353
    Images
    24
    Thanks to everyone for your help. I also got a reply from Harry Taylor who said that as long as the light is even then removing the lens shouldn't cause any problems. It seems even and definitely more so than with the lens in its tray but I'll have a printing session with it to check.
    Best regards,
    James



 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin