Page 1 of 3 123 LastLast
Results 1 to 10 of 21

Thread: Dark shade on negative

  1. #1

    Join Date
    Jun 2018
    Posts
    95

    Dark shade on negative

    I just developed a sheet and I noticed a dark strip on the right side of the image (see attached). I'm not sure what that could be (I used the sp45 development tank).


    Click image for larger version. 

Name:	hotel_16_corrected-Edit.jpg 
Views:	184 
Size:	31.5 KB 
ID:	191888

  2. #2
    bob carnie's Avatar
    Join Date
    Jan 2004
    Location
    Toronto, Ontario,
    Posts
    4,464

    Re: Dark shade on negative

    This is the single most common mistake in film processing here or on other sites I see.. Problem is neutral sky's or grey areas show process defaults.. To solve this the first 15 seconds of development good agitation must happen, as well sufficient chems to process in.

    I use Jobo system and even then I will invert and twist for 15- 20 seconds to ensure chem's get to all areas of the negatives and fast. hope you solve the problem .

  3. #3

    Join Date
    Jun 2018
    Posts
    95

    Re: Dark shade on negative

    Quote Originally Posted by bob carnie View Post
    This is the single most common mistake in film processing here or on other sites I see.. Problem is neutral sky's or grey areas show process defaults.. To solve this the first 15 seconds of development good agitation must happen, as well sufficient chems to process in.

    I use Jobo system and even then I will invert and twist for 15- 20 seconds to ensure chem's get to all areas of the negatives and fast. hope you solve the problem .
    Why would it happen on the right side of the image only?

  4. #4
    Resident Heretic Bruce Watson's Avatar
    Join Date
    Sep 2003
    Location
    USA, North Carolina
    Posts
    3,257

    Re: Dark shade on negative

    Quote Originally Posted by rpagliari View Post
    Why would it happen on the right side of the image only?
    Because you didn't cover the entire film with developer at the same time. For example, you were tray processing and put the film into the developer emulsion side up and didn't get that last bit on the right side pushed under the developer for a second or two (and that's all it takes) after the center was pushed under.

    Film development is weird stuff -- the first couple of seconds are crucial to getting even development.

    Bruce Watson

  5. #5

    Join Date
    Jan 2012
    Location
    Beijing
    Posts
    158

    Re: Dark shade on negative

    Quote Originally Posted by Bruce Watson View Post
    Because you didn't cover the entire film with developer at the same time. For example, you were tray processing and put the film into the developer emulsion side up and didn't get that last bit on the right side pushed under the developer for a second or two (and that's all it takes) after the center was pushed under.

    Film development is weird stuff -- the first couple of seconds are crucial to getting even development.
    That doesn't make sense in this case though. The SP-445 tank loads vertically.

  6. #6
    Jim Jones's Avatar
    Join Date
    Aug 2006
    Location
    Chillicothe Missouri USA
    Posts
    2,670

    Re: Dark shade on negative

    I always use a pre-wash to guard against this problem. Some film makers say a pre-wash is not needed. However, with a few film and developer combinations it is absolutely necessary.

  7. #7

    Re: Dark shade on negative

    I have not solved photography and don't know the answer to your question; however your problem interested me enough to watch a tutorial video about the SP-445 tank, so I have some idea of how the tank is constructed and how it is supposed to work, and on the basis of that very limited bit of information, I offer the following for your consideration. First of all, it is clear that this aberration is caused by uneven development, i.e., namely that the edge received less development than other parts of the negative and therefore the positive is darker in the affected areas. Second, and very importantly, the problem is not limited to the right side of the image. If you look very carefully at your scan you will see that the problem occurs on the left side as well. It is not so obvious along the full length of the image, but it is apparent in the lower left corner of the positive (the difference can be made more obvious by running the image through different filters in PhotoShop and, I assume, other comparable programs). So taken together, what does all of this suggest? My guess, and here I cannot overemphasize the word "guess," is that you may have inadvertently loaded the negative in the an orientation opposite to that recommended by the maker, i.e., the film was loaded with the emulsion side facing the continuous, unbroken, flat part of the holder vs. having the emulsion side facing outward toward the intermittently-spaced tabs that hold the sheet film in place to prevent it floating away from the holder. If that is indeed what happened, then it may be possible that the developer did not reach those edges of the film as quickly as the developer covered the remainder of the negative, e.g., because the film edges may have adhered slightly to the flat parts of the holder, partially on the positive left, and more completely on the positive right, for a brief time - certainly longer than 1 or 2 seconds - and the agitation provided was not sufficient to dislodge the stuck parts quickly enough to give even development across the entire negative. I do not know the proper name for this adhesion but what I am thinking of is not unlike what happens when a bit of liquid or humidity causes a dry negative to stick to another negative, to a polyethylene sleeve, or to some other material. I assume the problem could be exacerbated if you happened to use only one holder and cross loaded it so that there was more pressure on the edges than would otherwise occur, but I am certainly not suggesting that was the case. I do not assert that this theory is correct, and will not be the least bit embarrassed or ashamed if it is determined to be wrong. In the meantime, I too recommend that you pre-soak to minimize this problem going forward if you are not already using a pre-soak, and I also recommend that you contact the manufacturer of the SP-445 directly to see what they might have to say about the cause and cure, especially if the problem is a recurrent one.

    N. Riley
    http://normanrileyphotography.com
    Last edited by NER; 1-Jun-2019 at 20:05. Reason: to correct misspelling of site URL

  8. #8

    Join Date
    Jun 2018
    Posts
    95

    Re: Dark shade on negative

    Quote Originally Posted by NER View Post
    I have not solved photography and don't know the answer to your question; however your problem interested me enough to watch a tutorial video about the SP-445 tank, so I have some idea of how the tank is constructed and how it is supposed to work, and on the basis of that very limited bit of information, I offer the following for your consideration. First of all, it is clear that this aberration is caused by uneven development, i.e., namely that the edge received less development than other parts of the negative and therefore the positive is darker in the affected areas. Second, and very importantly, the problem is not limited to the right side of the image. If you look very carefully at your scan you will see that the problem occurs on the left side as well. It is not so obvious along the full length of the image, but it is apparent in the lower left corner of the positive (the difference can be made more obvious by running the image through different filters in PhotoShop and, I assume, other comparable programs). So taken together, what does all of this suggest? My guess, and here I cannot overemphasize the word "guess," is that you may have inadvertently loaded the negative in the an orientation opposite to that recommended by the maker, i.e., the film was loaded with the emulsion side facing the continuous, unbroken, flat part of the holder vs. having the emulsion side facing outward toward the intermittently-spaced tabs that hold the sheet film in place to prevent it floating away from the holder. If that is indeed what happened, then it may be possible that the developer did not reach those edges of the film as quickly as the developer covered the remainder of the negative, e.g., because the film edges may have adhered slightly to the flat parts of the holder, partially on the positive left, and more completely on the positive right, for a brief time - certainly longer than 1 or 2 seconds - and the agitation provided was not sufficient to dislodge the stuck parts quickly enough to give even development across the entire negative. I do not know the proper name for this adhesion but what I am thinking of is not unlike what happens when a bit of liquid or humidity causes a dry negative to stick to another negative, to a polyethylene sleeve, or to some other material. I assume the problem could be exacerbated if you happened to use only one holder and cross loaded it so that there was more pressure on the edges than would otherwise occur, but I am certainly not suggesting that was the case. I do not assert that this theory is correct, and will not be the least bit embarrassed or ashamed if it is determined to be wrong. In the meantime, I too recommend that you pre-soak to minimize this problem going forward if you are not already using a pre-soak, and I also recommend that you contact the manufacturer of the SP-445 directly to see what they might have to say about the cause and cure, especially if the problem is a recurrent one.

    N. Riley
    http://normarileyphotography.com
    Thanks a lot NER. I did not do pre-rinse, but I think your suggestion is s. There is spot on. There is no way to check but it makes perfect sense. I will be more careful next time.

  9. #9

    Join Date
    Dec 2018
    Location
    Guelph, Ontario, Canada
    Posts
    292

    Re: Dark shade on negative

    N. Riley's idea is highly probable, and you can check for yourself. Measure the width of the plastic bars on each side of the holder. If they correspond, that's your answer. Early on with this tank, I managed to load two sheets in the same side! It happens.

    Another suggestion for future: Tim, the creator and seller of the SP-445, is quite responsive on email. He helped me figure a few things out over email.

  10. #10

    Join Date
    Jun 2018
    Posts
    95

    Re: Dark shade on negative

    I developed another negative with the mod54 and got the same result. I think it might be the bellows that is shading a bit.

Similar Threads

  1. Dark corner on bottom left of the negative
    By rpagliari in forum Darkroom: Film, Processing & Printing
    Replies: 7
    Last Post: 13-Apr-2019, 20:01
  2. Dark Spots on Negative
    By Justin Roxbrough in forum Darkroom: Film, Processing & Printing
    Replies: 6
    Last Post: 29-Aug-2018, 11:32
  3. Dark stripes and mottles across 4x5 B&W negative film
    By younghoon Kil in forum Darkroom: Film, Processing & Printing
    Replies: 15
    Last Post: 5-Mar-2015, 07:50
  4. Artifact (dark ray) on Negative
    By Tim Povlick in forum Cameras & Camera Accessories
    Replies: 25
    Last Post: 11-Oct-2011, 06:33
  5. Lee shade vs Arca Swiss Compendium Shade
    By postman in forum Cameras & Camera Accessories
    Replies: 9
    Last Post: 6-Nov-2010, 10:39

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
  •