Repairing the light seals on my Cannon AT-1

Of Sky

I have already said a lot about how much I love my Canon AT-1 so I won’t say any more. For a while using the camera resulted in my fingers and film canisters being covered in a black gunge. It didn’t take me long to realise that the viscous material was in fact the light seals from inside the back of the camera. I chose to ignore this for as long as I possibly could but eventually the light leaking into the back of the camera started to affect the images that I was capturing. Sometimes this resulted in some pleasant surprises, like the image of the fly above where a band of light frames the insect and adds to the final image. In other cases this effect was much more dramatic and not really what I was looking for like the image from Donnington below.

Image damaged by leaky light seals

Failure of light seals in older film cameras is not uncommon and is certainly not specific to the AT-1 or other AE models. If you start to see the tell tale lighter areas in your images I would suggest that you are probably better fixing it sooner rather than waiting like I did. Yes I ended up with some nice images but I have also missed out on others which would have showed some potential if it weren’t for the dreaded light leak. When it comes to fixing the light seals you have two options, buy a kit and fix it yourself or send the camera away for servicing. The value of the camera is probably going to have an impact on your decision but the fix is fairly simple if you have the time. Personally I was keen to try and fix my camera myself and I wanted to share my experiences in this blog post.

What you will need

  • A light seal kit for your camera (Can be found on eBay)
  • A sharp knife
  • Some tissue paper or kitchen roll
  • Some wood or a surface to cut on
  • Solvent (I used lighter fluid)
  • Wooden cuticle stick
  • Tweezers
  • Cotton wool buds
  • A metal ruler
  • Some instructions
  • Time, lots of time
  • Tea (This probably goes without saying)
  • A steady hand

Out of all of those things the most  valuable item IMHO was the cuticle sticks. I picked up a pack of 6 for 50p which meant that I could throw them away and pick up a clean one when I needed to. The fact that they have one pointed end and one angled end means that you can use them for all sorts of things and they are soft enough that they won’t damage your camera. When it comes to a sharp knife I found that a Stanley knife with a brand new blade was sufficient but I did swap the blade for a fresh one part way through just to be sure.

When it comes to a kit and instructions a quick Google search should reveal something specific for your camera. Personally I picked up my kit from eBay but the instructions that came with it were pretty rubbish so I was able to find some more with another quick search:

You could of course just buy the foam and cut it all yourself but I couldn’t imagine doing that as the kit makes things much, much simpler. The pieces of foam you will be dealing with are pretty small and having a straight edge to work with is really useful.

The other thing worth noting is time, you need to leave yourself plenty of time to do this job as its extremely fiddly. I spent about 3 hour fixing my camera. I expect that you could do it faster but I am pretty meticulous with the way I do things and I wanted to make sure I got this just right.

Getting started

Lay all of your items out on a working space which is going to be big enough for everything you need. I used a small coffee table and this was ample. Remember that you are going to be there for a while so make sure you can sit comfortably. My other tip would be to RTFM. If you have instructions read them from start to finish. I missed a part on my instructions and as it turned out it didn’t apply to my camera but my heart stopped for a moment when I read it.

Getting ready to fix the light seals

Removing the old light seals

Despite the fact that the seals in my camera had disintegrated into nothing in places, it still took quite a while to clean what remained of the original foam that made up the light seals. Things are much easier if you can remove the film door from the back of the camera. The AE series cameras have a small catch on the door hinge that allows you to room the door easily. I also found that leaving my 35mm prime on the camera body made it easier to hold the camera and meant that I wasn’t worried about damaging the mirror on focusing plate whilst cleaning the back of the camera.

Cannon AE seriers film door catch

The catch which releases the film door of Canon AE series cameras

Ready to start

Ready to start removing the original light seals

A solvent is a must for this step but use it a small amount at a time as you don’t want to end up damaging the exposed components of your camera. I used lighter fluid as my solvent just because it is readily available. I found three techniques for applying the solvent without pouring it all over my camera:

Solvent applied with cotton bud

Cotton wool buds are good for larger areas with good access.

Solvent applied with kitchen roll

Kitchen roll soaked in solvent can be applied to local areas with difficult access.

Solvent applied with cuticle stick

Small amounts of solvent can be poured against a cuticle sticks to drop solvent into localised areas.

Work in one area at a time, apply solvent and then use the cuticle sticks to scrape away the damaged foam. Keep the cuticle sticks clean as you go so you don’t drop the gunge into the inner working of the camera and switch to a new stick once it becomes too clogged to clean.

You want your camera to be completely free of old adhesive so once you have cleaned your camera go over it again to make sure you haven’t missed anything. You want to be able to move the new seals around once you have stuck them down and this will be extremely difficult if there are bits of old glue and foam.

Almost finished film door

Mostly clean film door with some adhesive still remaining

Clean camera back

Clean camera back ready to have the new light seal foam applied

Applying the new seals

The first thing you need to do before you start applying the new seals in tidy your workspace. At this stage I had old foam, solvent soaked kitchen roll, used cotton wool buds and cuticle sticks all over the place. You are going to need all of that space for cutting the foam into shape so its a good idea to start with a clean working area.

Take note that your kit will probably come with two thicknesses of foam. My kit contained 1mm thick foam for the light seals and 2mm thick foam for the mirror damper. Make sure you check your kit before you start as you wouldn’t want to use the wrong foam.

My instructions suggested cutting all of my foam up front but I decided that I would rather cut the foam as I needed it. That way I could check the foam as I went and make adjustments for the next piece if I needed to. I started with the seals on the back of the camera body. My approach was gently press the foam into the groove and use the cuticle stick to make a mark where I should cut. The AE cameras have a catch in the top groove which moves inward when the door is shut. I made sure that I was as close to this as I could be without stopping it from moving. There is no glue on the strips which go into the top and bottom of the camera body back so this is fairly simple.

Checking the length of foam needed

Here I am checking the length of foam that is required

Cutting the foam

Cutting the top and bottom light seals is extremely easy

The next step for me was the foam at the hinge end of the camera back. My instructions has suggested sizes but I found it easier to make my own measurements as I knew this would create a better seal. Putting pressure on the foam with a metal ruler and making a single cut meant that I was able to get the shape I wanted.

One of the best tips in my instructions was to lick the adhesive on the foam before applying it. I found that licking the adhesive and the area of the camera where I was sticking it gave the best result. This meant that I could move the foam around once I had placed it. I could then hold it in place with a cuticle stick (see how useful they are) for a minute or so until it was stuck in place. For placement I used tweezers so that I didn’t touch the adhesive and so that I could see what I was doing. For moving the foam around once in place I found that it was easier to use a cuticle stick.

The other strips on the film door where fairly similar. The only thing that I found was that my camera also had felt / foam seals at the sides of the latch end of the film door. This meant I had to cut shaped pieces of foam and slide them into place. This was probably the most fiddly part of the whole fix but licking the adhesive meant that I could move the foam fairly easily.

Part way through fixing the new light seals

Part way through fixing the new light seals

New catch end door seals

New catch end door seals

New hinge end door seals

New hinge end door seals

Replacing the mirror damper

This is a good point to replace the film door on your camera and clean your working area. You don’t want to undo all your good work on the rear of the camera.

I thought that my mirror damper was still OK but when I touched it most of it came away with my finger. I then realised that some of it was stuck to the mirror. You shouldn’t use solvent to remove the damper foam as you may damage the focus plate. Instead use a fresh blade and gently cut the foam away. Once most of it is gone you can use a cuticle stick to scrape away any unwanted adhesive. Using a very small amount of solvent on a cotton wool bud I was able to clean the mirror but I would suggest you are very careful if you decide to do this too.

At this stage I cleaned up my work area one last time before cutting and applying the last piece of foam. Remember that the mirror damper is normally a thicker piece of foam than that which is used in the back of the camera. Its job is to stop the mirror hitting the inside of the camera after all.

Old mirror damper

The old mirror damper still in place

New mirror damper

The new and improved mirror damper

All done

And there you have it. You should find that your light leak problems and all fixed. This fix does take a bit of time but I think it is well worth it. I’m pretty proud of the fact that I was able to do a pretty clean job. I hope that sharing my experience has been useful to some of you or perhaps made you feel a little less apprehensive of fixing your own camera.

Fully repaierd camera


What can you learn from shooting film?

In my last post I mentioned that my beloved Canon AT-1 deserved a blog post all of it’s own so here it is.

Canon AT-1


Back when Mark Wahlberg was Marky Mark I purchased a my first SLR second hand from a family friend. He had made the move to digital and he was happy for me to take his Canon AT-1 camera body with a 35mm prime, a 70-200mm telephoto and a flash off of his hands. The family friend gave some basic instructions on how to use the camera and off I went. Whilst my early photography wasn’t the best, much of what I did at the time was about experimentation. I have a few sets of images where I am trying out different techniques and approaches to imaging a subject.

This early exposure to photography still has an impact on what I do today. I love to experiment with a subject trying to understand how different approaches to composition, exposure and other techniques can alter the picture that is produced. The act of imagining the scene that will be captured by the camera with its single all seeing eye and it’s  two dimensional view of the world is still extremely thrilling to me especially when the image that is created matches the idea of what I was trying to see. For me shooting film increases this excitement even more. The digital screen on the back of a modern DSLR is a useful tool and has definitely helped me to improve my photography but it takes away from the thrill of not knowing what has been recorded, unlike the images that are recorded on the cellulose of a 35mm reel of film.

Metal Hills and Opaque Clouds

Some of you reading this will have never have shot film and some will be thinking “why bother?”. I would imagine that for many not knowing what has been captured in an image is frustrating rather than exciting. I understand this viewpoint completely but I would still recommend shooting film to anyone who has an interest in photography. IMHO there are many reasons why shooting film is good for your photographic ability and it’s not just the excitement. Shooting digital is cheap in more than just financial terms, it’s far too easy to reel off 100s of the same shot with a digital camera. Whilst there are some benefits to the ability to churn out a great number of images, one of the dis-benefits is that it can start to devalue the pictures that you take. I don’t expect I am alone in discounting many of the pictures I have taken on my digital camera.

So what makes film different? If you take the same approach to a roll of film as you would a SD or flash card then not much. I would suggest however that there are features of film photography which will mean that isn’t the case. My Canon A series camera requires you to manually wind the film between exposures and added to that it doesn’t have any modes other than fully manual. It has an in camera light meter which is extremely handy but it is nothing more than a needle which moves up and down depending on the amount of light hitting the sensor. As a photographer you have to make choices about your aperture and shutter speed to get the right exposure. In addition to this you can forget about changing the ISO. Not unless you want to change a roll of film between shots and increase the costs even more.

If you weren’t thinking “why bother?” earlier then you may well be thinking that now. Whilst I have pointed out the some of differences of using a film camera like my Canon At-1 I haven’t really said how all of this helps. For me the biggest aspect is time. All of the things that I have mentioned mean that taking a single image takes more time. You have to think about what you are doing, you have to remember to wind the film, you have to think about the exposure and the cost of pressing the shutter. All of this slows you down and in doing so you start to think differently about what you are doing. For me I started to think about what is important. The content and composition of my images is at the forefront of my mind. I start to see things differently and I start to enjoy the process of advancing the film as I look at the world around me. More often than not I find most of my 36 exposures are worth keeping.

Another thing that I love about using my Canon At-1 is the way it feels in my hand. In comparison to my D7000 the AT-1 it’s a featherweight and well suited to street photography. Even when fitted with a 70-200mm its much more inconspicuous than some of the modern glass available for todays digital SLRs. Coupled with a 35mm prime you get the benefits of being invisible in a crowd, similar to how you would with a compact system camera with the benefit of a “full frame” 35mm negative. In addition to all of this it looks fantastic. Who needs to splash out on the vintage looking Nikon Df at close to £2.5K when you can have the real thing at a fraction of the cost.

Canon AT-1 and Nikon D7

A comparison between my Nikon D7000 and my Canon AT-1

Canon FD and Nikon F lens comparison

A comparison between a modern 70-22mm telephoto and the 70-200mm lens that I use with my Caannon AT-1

I know that shooting film won’t be for everyone but one of the best things is that you can pick an exceptionally good camera at relatively small cost so even if you only use it every now and then it’s not a massive investment. A quick search on eBay will reveal a number of different cameras that will get you started. Some even come with a number of serviceable lenses. The only thing to bear in mind is the cost of film and processing. Expect to pay somewhere around £4 for 36 exposures and upwards of £3 for processing. Personally I opt to have my film processed and scanned so that I can choose the images that I like and order prints. I normally use Ag Photo Lab who offer free postage in the UK and have always offered me a reliable service however you will find many companies offering similar services. Like digital photography you can print the images yourself. I have recently become the owner of a complete darkroom set up which I found on eBay. I think perhaps that is a story for another time.

If you already shoot film or you are thinking about giving it a go I would be interested in what made your experiences. Please reply by commenting on this post.