Hasselblad A12 Light Leaks?

Tom Cross · Apr 27, 2016

Hi all, I'm looking for some opinions regarding some light leak issues I appear to be having with an A12 back I bought from a camera shop a while ago. They have since had it back, looked at it and sent it back confirming there is nothing wrong with it. It arrived back yesterday and I ran a roll through it and processed.

The shop thought it was me not loading the film correctly (saying it was cause the film to be slack) and sent me instructions for the A12 back along with some condescending post-it notes placed on and in the back! After double checking I found I was loading it correctly!! They also said they had checked the seals (they didn't say how).

I've put some photos of the freshly developed negative in a Dropbox folder here : https://www.dropbox.com/sh/5sqmi51xgdmomho/AADAoR-0q9PnylzD5r0UdMB2a?dl=0

Hopefully someone will recognise the pattern of exposure along the edges of the negative. I have had a similar pattern from the first roll I took with this back but on that one the leak went further into the negative onto the frame itself. This roll was taken indoors, the first roll with worse leakage was outdoors.

shutterfinger · Apr 27, 2016

Time to look at the body. Look at the light seals around the viewfinder, focusing screen, mirror.

What I'm seeing in the uper center of the image area may be the background of the shower showing through. Dark film edges are not a problem.

Is that the latest incarnation of the "Chuckie doll"?

MattKing · Apr 27, 2016

That isn't a problem with the back.

You aren't keeping the film and backing paper tight enough on the spool - either when loading the unexposed film into the back or more likely unloading the exposed film from the back and sealing the finished film.

It is not an uncommon thing to see, and usually has no practical effect on your photos unless you allow the backing paper to get really loose.

Tom Cross · Apr 27, 2016

Yeah my son does look a bit like a chucky doll - we don't feed him after midnight either! If it was a problem with loading/unloading/something I do then I would expect to see these issues on rolls from other backs too? I am always careful to keep the roll tight

shutterfinger · Apr 27, 2016

Load a spool with the backing paper of a processed roll like it was fresh film. Pull the darkslide and use a #2 pencil to mark the frame opening of the back. Advance the paper 1 frame, attach the back to the camera. With the camera on B and no lens mark the frame opening of the camera on the backing paper. Remove the paper from the back and check the alignment of the frame opening marks, they should be the same. Check other backs with the paper and their alignment against the suspected bad one.

In total darkness with no film holder attached, the viewfinder removed, no lens, and the mirror up shine a bright light source such as a 2AA mini mag flashlight set to spot at 2 inches or a small LED flashlight around the view opening while observing the back opening. Now close the mirror and shine the light from the lens opening. No light should be getting through in either instance.

Tom Cross · Apr 27, 2016

shutterfinger said:
Load a spool with the backing paper of a processed roll like it was fresh film. Pull the darkslide and use a #2 pencil to mark the frame opening of the back. Advance the paper 1 frame, attach the back to the camera. With the camera on B and no lens mark the frame opening of the camera on the backing paper. Remove the paper from the back and check the alignment of the frame opening marks, they should be the same. Check other backs with the paper and their alignment against the suspected bad one.

In total darkness with no film holder attached, the viewfinder removed, no lens, and the mirror up shine a bright light source such as a 2AA mini mag flashlight set to spot at 2 inches or a small LED flashlight around the view opening while observing the back opening. Now close the mirror and shine the light from the lens opening. No light should be getting through in either instance.

Just tried the second item - nothing showing. I will do another roll but unload in complete darkness. Like I said, this negative isn't too bad as it was taken indoors, but the first one was outdoors and was worse.

Philippe-Georges · Apr 27, 2016

There are a few possibilities (causes and solutions):
- Dropping an unpacked roll on the border of the plastic spool, exposed or not, is enough to fog the borders of the film. Due to the impact, the rim of the spool wil 'move' and let some light in.
- This can be mechanical fog, while (un-)rolling the film it might rub agains the rim. Some emulsions are more or less sensitive to that.
- As already suggested, the film might not be tightly enough rolled on the spool.
- It's not a light seal leak in the film chassis, these marks are completely different and mostly across the image (unless it's in the very beginning of this issue, worse to follow).
- Loading and unloading film in intensive light is not wise, do it in subbed light (turn your back towards the light source and handle the film in your own shadow).
- In some very, very, rare occasions, it could be du to static electricity discharging while the film is rubbing over the plastic film spool, wether it is the original spool or the plastic reel used to hold the film in the developing tank.
- Be careful while handling film, do it slowly and attentively.
- Be aware of the ever present coincidence of different unknown and colliding elements of causality.
- Ask Murphy.
- As long this fog is not on the image itself, don't bother...
- And above all, do not stop shooting film!

Tom Cross · Apr 27, 2016

Thanks all. It does seem odd that this is limited to one back only - perhaps it's not winding the film tight enough. I have just taken a few images around the yard at work, unloaded in complete darkness and stored in lightproof box which it wont come out of until its in the changing bag. We'll see what happens.

shutterfinger · Apr 27, 2016

You can load in dim light, tape the shell hinge, latch, and body attach seams with black electrical tape then unload in dim light to total darkness to eliminate or minimize light as the cause.
Marking the backing paper can show winding problems. There are two sets of guides, one for the paper and one for the film. If the holder is winding .02 or .03 millimeter off center it will be pushing the film tight against a paper guide resulting in the pressure exposure along one edge.

Philippe-Georges · Apr 27, 2016

The one back is not the other!
They all have their own light seal (that can leak).
This light seal is located in the slit where the inox light protecting slide is put in. Actually it's the only real weak element, made of plastic, in the Hasselblad that deteriorates fast.
On YouTube there are numerous videos demonstrating how to replace that seal yourself, if you can find a genuine replacement part of course.

Tom Cross · Apr 27, 2016

Sent photos to Classic V - said based on photos its a classic light seal/darkslide problem easy to fix.

rulnacco · Apr 27, 2016

If it's just a light seal problem in the dark slide slot, that's so easy to fix, you can do it yourself--takes about 10 minutes the first time you do it, even less after.

I buy the seals on eBay from seller blackbird711 (http://www.ebay.co.uk/usr/blackbird711?_trksid=p2047675.l2559). He'll post them to the UK for a minimal charge, and includes detailed instructions. I actually did a bit of profitable business for my local second-hand camera shop by installing seals on backs for the proprietor and his customers--and I re-sealed all my own backs as well.

MattKing · Apr 27, 2016

Tom Cross said:
Thanks all. It does seem odd that this is limited to one back only - perhaps it's not winding the film tight enough. I have just taken a few images around the yard at work, unloaded in complete darkness and stored in lightproof box which it wont come out of until its in the changing bag. We'll see what happens.

Some times the geometry of a particular camera or back makes it harder to get the film out without loosening the backing paper. Have you been tightening the paper on the spool before you take the spool and film out of the back?

If that is the nature of the problem, then the experiment you are referring to in this post will likely show a difference.

Hasselblad A12 Light Leaks?

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