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Robclarke
4-Aug-2017, 05:07
I occasionally have a negative like this. This was processed in a sp4-45 tank the other 3 negatives came out fine. It always happens like this I get one bad one and the others are fine. I am pretty sure the film holder was properly inserted into the camera.

https://farm5.staticflickr.com/4338/35558628483_77107844ce_c.jpg (https://flic.kr/p/Wbcgpr)Untitled (https://flic.kr/p/Wbcgpr) by biotecbob (https://www.flickr.com/photos/robertedwardclarke/), on Flickr

Ken Lee
4-Aug-2017, 05:11
http://www.kennethleegallery.com/images/forum/SqueezeBack.jpg

Whenever removing and inserting a dark slide with one hand, squeeze the back with the other hand, to keep the light seal closed.

Robclarke
4-Aug-2017, 05:20
So you think it is a light leak rather than development problem? I am using a Linhof Master Technika camera I think the camera back holds the film holder pretty tight but will try implementing your advice in future. Thanks.

Jim Jones
4-Aug-2017, 06:13
Light leak, possibly in the film holder. Note the light leaking into the area that the holder flap should cover. Many of my film holders are uniquely identified by identifying notches filed in the flap so problems with a holder can be traced to a particular holder.

Ken Lee
4-Aug-2017, 08:27
Jim may be right of course :)

When we shoot a portrait like yours, the subject's head appears at the lower end of the negative. If like most people you load your film so that the notch is near the holder flap, that's where the light leak appears.

It's possible that the film holder was not positioned snugly. When removing or inserting the dark slide, a little leverage (or torque) can unseat the film holder, especially if it's an older film holder.

But as Jim suggests, perhaps the tape or flap is broken or loose.

Doremus Scudder
4-Aug-2017, 11:07
Definitely a light leak. I doubt that it's a problem with the tape or the flap on the holder (even if the tape is completely gone, the flap should be lightproof as long as it's seated properly). Check the holder for cracks/separation in the area corresponding to the upper right of the image. If that looks alright, then, as Ken suggests, make sure the holder is seated correctly before pulling the darkslide, and make sure to pinch the camera back to the body when pulling and re-inserting the slide.

If the problem persists with other holders, then it's time to check the camera back for leaks (probably a good idea anyway...). Look for bellows separation, warping, etc., anything that would cause a misalignment to let light in around that area of the camera that corresponds to the upper right in the image you show.

Best,

Doremus

Ken Lee
4-Aug-2017, 12:36
...make sure the holder is seated correctly before pulling the darkslide,

Excellent point (in addition to your other excellent points).

A spring-loaded back will hold a wrongly seated film holder in place just as firmly as it holds one in the correct position.

Clasping the camera back even more tightly doesn't fix the problem because by then it's too late.

I've had to learn the hard way, to check the film holder and make sure it is seated properly.

Robclarke
13-Sep-2017, 06:26
I am still having problems with light leaks. I did some testing with the holders in the spring back.

I noticed that there is a bit of play in that after it is inserted I can pull the film holder slightly out before it comes to a hard stop. This means that there is a small gap between the edge of the film holder frame and the film holder but with the film holder still firmly seated against the camera back. I wonder if this small gap could cause a light leak?

Can anyone else with a Technika see if they have this play in theirs?

Neal Chaves
13-Sep-2017, 06:55
Could be a dark slide insertion problem. Did you have a light source over the back of the camera? If so, just as outside in bright sunlight, rotate the back and insert from below or if horizontal from the side opposite the sun. One reason I suspect this is the angle of the fogging. If you insert a dark slide one corner first it opens the light trap all across its length. Insert the slide straight in.

consummate_fritterer
13-Sep-2017, 12:01
There's no question it's a light leak. The fog leaks over into the film's rebate. And I'll ad that I think it happened during either film loading or unloading because of the intensity and angle of the fog.

MikeS
14-Sep-2017, 17:53
What brand of film holders are you using? I ask, because if you're using Linhof brand film holders, they load slightly differently than 'normal' film holders. Also, are you using 'newer' plastic film holders like Fidelity, or such, or if you're using older wooden Graflex brand film holders, that can make a big difference. It's fairly normal for a film holder to have a slight amount of play right to left even when it's sitting against the camera back properly. Do you have your film holders marked so you can tell which holder the fogged film came out of? Is it always the same one? If you don't have your film holders marked, I would suggest that you mark each one with either a notch code, or a number on a small piece of film mounted so it marks the film, such as the ones in the images attached to this message. Once you have a way to tell which film holder is fogging the film, you can go further to investigate the fogging.


169820 169819

mikestr
30-Dec-2017, 08:38
Did you ever solve this mystery? Assuming you haven't, I would check to see if this is the result of an incompletely inserted film holder. With many 4x5 spring backs it is necessary to give an extra shove to get the holder past the last "ridge" so that it's in all the way. Take Ken's advice regarding the need to squeeze the focus panel and rear standard when removing and inserting the dark slide so you don't all move the camera at the same time. I always check the far end of the holder after insertion to see if it's flush with the frame of the camera back. If not I will have a light leak when the dark slide is pulled. In your example I might also suspect that the holder is not lying flat and perpendicular to the lens axis, as the bottom of the image is so much less focused than the middle (lower arms v shoulders) even though the image appears to be taken straight on (this could however be the result of a tilted lens standard. This can also be the result of an incompletely seated holder. Ignore the comment about the tape on the flap: It serves only as a hinge and has no light-sealing function; the flap is designed as a light trap.