Page 2 of 3 FirstFirst 123 LastLast
Results 11 to 20 of 21

Thread: What caused this "half moon dot" in the attached photo?

  1. #11

    Join Date
    Dec 2015
    Location
    Erie, Colorado
    Posts
    72

    Re: What caused this "half moon dot" in the attached photo?

    The only time we've seen the SP-445 film holders interfere with processing, is when the negative is loaded in backwards (we've had several customers admit to that.) That leaves very distinct vertical lines if they're using the original holders. Haven't had anyone do it (or admit it to us) with the new holders.

    Besides, Tom Wakefield (on the facebook thread) spotted it in another image of mine. I missed it, since it's on the white part of the church.
    Click image for larger version. 

Name:	centerville church006 LR.jpg 
Views:	37 
Size:	76.1 KB 
ID:	164247
    Click image for larger version. 

Name:	centerville church006 crop.jpg 
Views:	40 
Size:	53.4 KB 
ID:	164253

  2. #12

    Join Date
    Sep 2010
    Posts
    833

    Re: What caused this "half moon dot" in the attached photo?

    I have seen similar half moon-shaped defects on roll film due to crinkling the film when loading the reel, but never on sheet film. As you probably know, stressing the film can cause a build up of extreme density at the site.

  3. #13

    Join Date
    Nov 2015
    Location
    Alberta, Canada
    Posts
    105

    Re: What caused this "half moon dot" in the attached photo?

    Are they on the negative Tim?

    Thanks
    Dave

  4. #14

    Join Date
    May 2015
    Location
    SooooCal/LA USA
    Posts
    2,802

    Re: What caused this "half moon dot" in the attached photo?

    Check the neg carefully to see if there is something stuck to the neg, or a density spot (as this is white, and didn't allow light through the neg there)...

    You can also sell the image to the tabloids (or Ripley's) if you come up with a good enough story... ;-)

    Steve K

  5. #15

    Join Date
    Dec 2015
    Location
    Erie, Colorado
    Posts
    72

    Re: What caused this "half moon dot" in the attached photo?

    Dave,
    Appears to be in the emulsion; part of the image.
    No dust, dirt etc.
    Might have it on another negative as well.

    Tim


    Quote Originally Posted by DHodson View Post
    Are they on the negative Tim?

    Thanks
    Dave

  6. #16

    Join Date
    Oct 2012
    Location
    Boulder, co
    Posts
    627

    Re: What caused this "half moon dot" in the attached photo?

    they both appear to be on the same part of the negative. curious... is there any part inside the camera that is shiny and could focus a bit of a flare somewhere?
    ~nicholas
    lifeofstawa
    stawastawa at gmail

  7. #17

    Join Date
    Sep 2003
    Location
    La Luz del Oeste, Albuquerque NM
    Posts
    538

    Re: What caused this "half moon dot" in the attached photo?

    Well, another thought:
    Quote Originally Posted by stawastawa View Post
    they both appear to be on the same part of the negative. curious... is there any part inside the camera that is shiny and could focus a bit of a flare somewhere?
    Both white 'blips'--on the shingles and next to the window--have the same shape and approximately the same orientation. Look at, for example, the upper right side of the blip: something like a curved 'cap' is in this quadrant of the blip.

    So I might go back to the camera, check for light leaks, problems with inserting film holders, etc.
    Peter Collins

    On the intent of the First Amendment: The press was to serve the governed, not the governors --Opinion, Hugo Black, Judge, Supreme Court, 1971 re the "Pentagon Papers."

  8. #18

    Join Date
    Dec 2015
    Location
    Erie, Colorado
    Posts
    72

    Re: What caused this "half moon dot" in the attached photo?

    I think I found the problem: there's a bubble in the lens! Of course, the bubble will move with the movements; so it shifts from one photo to the next. Never noticed this before; I guess you have to aim into the sun just right.
    Click image for larger version. 

Name:	bubble.jpg 
Views:	16 
Size:	15.6 KB 
ID:	164268

  9. #19

    Join Date
    May 2001
    Location
    Switzerland
    Posts
    1,330

    Re: What caused this "half moon dot" in the attached photo?

    No I do not beliefe your bubble theory, I have also an old lens with 2 bubbles but I didn't see something like this in my negs from this lens! Could it be that a tiny bit sunlight hit the front lens element! Is it a old uncoated lens?

    Cheers Armin

  10. #20
    Nodda Duma's Avatar
    Join Date
    Nov 2014
    Location
    Batesville, Arkansas
    Posts
    1,116

    Re: What caused this "half moon dot" in the attached photo?

    A bubble in the lens is as out of focus as the lens itself. The "aperture" diameter of the bubble is so small that it would be a shadow and not a spot of light. Bubbles in lenses create scatter, reducing contrast ever-so-slightly. They don't, however, create focused spots.

    I'd suggest checking for pinholes in your bellows.
    Newly made large format dry plates available! Look:
    https://www.pictoriographica.com

Similar Threads

  1. Ilford FP4+ or Delta 100: "moon crater" pattern on skies after a long exposure
    By alps-art.ch in forum Darkroom: Film, Processing & Printing
    Replies: 19
    Last Post: 8-Oct-2016, 03:14
  2. Asanuma "half-plate"?
    By Scott -- in forum Cameras & Camera Accessories
    Replies: 45
    Last Post: 22-Feb-2011, 12:57
  3. Can one "half stop" the shutter?
    By riooso in forum Lenses & Lens Accessories
    Replies: 7
    Last Post: 20-Jul-2006, 08:04
  4. Ansel Adams photo, Moon and half dome
    By william mundy in forum Resources
    Replies: 10
    Last Post: 5-Aug-2004, 17:45

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
  •