Porous shutter blind repair on iiif

[seneschal]

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A week ago I acquired a Summarit 1.5 from a New York auction. Cleaned the lens (subject of another post) and did a quick clean of the iiif that it was attached to. The camera looked nice, once cleaned, shutter speeds sounded OK... but, once wound on and the shutter was cocked, I could see that there were some little wrinkles in the first blind. Impatient to find out whether the camera would leak, whether shutter speeds would be accurate enough for correctly exposed images and whether the rangefinder would be synchronised I loaded the camera with a roll of FP4 and went out to shoot. Last night I got the TIFFs back, the negs take a few days longer. 

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As I suspected... and as you can clearly see... the blind is porous... leaking light all over the place. This is the first blind, if I am shooting and have wound on immediately, the burn on the film is directly proportional to the amount of time until the next shot (I have not put the lens cap on between shots). Some of the frames are significantly worse than this, but this shows nicely where the little pinholes are.

Hmm... I said in my post about the Summarit that I didn't really "want" the camera... viewed it as a free gift with the lens, I already have a very nice iiif body which I bought to replace the iiif that was stolen 10 years ago.

Unfortunately, having got the camera, and seeing it look so nice once cleaned a bit, I have already become attached to it. I cannot just leave it with a leaky blind. So last night I did some research, both about the shutter, how to get at it and options for fixing the rubberised silk where it has become porous.

Here's a link to the video which gave me the confidence to believe it's easy:

https://www.youtube.com/watch?v=H-gVXjAe448

I was not over keen on the idea of liquid rubber, as I was concerned about how stiff it might be once cured, although it was clear from the video that it had worked in this case. My biggest worry was getting something that could be applied really, really thinly, in multiple layers, would remain perfectly flexible, not add weight beyond milligrams and thereby adversely affect the motion of the shutter. I was concerned about the viscosity of the liquid rubber and how thick this would be in application.

Just in case I changed my mind I ordered some "Black Witch" neoprene which I have used in the past with wetsuits... it arrives tomorrow.

This morning I removed the 6 screws and the casing from the iiif, followed the video advice on using a card holding the film pressure plate and springs in place, to have a proper look at the shutter.

The second blind is perfect. Shining an extremely bright CREE LED flashlight through the first blind I got this:

AAGGGHH! You would think that something like this would immediately fog the film, but you can see from the first photo that even this amount of porosity allows less light than you would expect through the blind.

I just couldn't wait until the neoprene arrived and I wasn't sure how I would thin it anyway. So I did a bit more research, taking the idea of "pop-up liner" from the video and looking more at fabric paints, flexibility, application methodology and degrees of opacity. Loads of web content read and digested I think I understood more and was zeroing on on how to achieve what I wanted.

In the end I actually went to my local fabric and sewing shop. I got some advice from them about creating designs on fabric and then followed up on their advice to visit an arts and crafts store.

They were able to advise expertly on how to paint on silk, without losing the draping capability and how to achieve flexibility without losing opacity.

It is really satisfying to take knowledge and experience from two different craftspersons and then apply both together in a different application... this is what the original craftsmen who built cameras were doing... there was no precedent then.

I got advice on which products could be useful to me, designed specifically for silk, how to apply it and which brush to use, even to use a nylon brush rather than sable. FANTASTIC!

So here's all you need to do this yourself.

• Wera flat blade screwdriver (118004, 0.3mm, 1.8mm, a 0.4mm screwdriver is too thick for the screws that hold the casing in place... use the correct tool and you will not damage the screwheads)
• Super bright flashlight (you will find any porosity remaining after each coat, even out to the edges of the blind)
• Pēbēo Setasilk (just in case you have lost dye from the blind, I did not use this in the end)
• Pēbēo Setacolor Opaque (I did a total of 4 super thin layers, allowing it to dry completely between layers, and releasing the shutter at least 20 times between coats, before I was happy that the blind was 100% light tight and would be stable when used in anger, I may do a couple more for safety's sake)
• Number 1 ProArte Nylon brush

Here's the finished shutter, good as new in terms of being light tight. I cannot notice any difference in shutter timing... but will load another test FP4 and see how it goes. The real proof of the pudding will be ISO 3200!!! Not sure I dare try that until after I see the results with FP4.

Edited July 10, 2021 by seneschal

[spydrxx]

Brave man you are! I’d have sent it off to Youxin or DAG.

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[seneschal]

In the end it's a question of how much damage can I do... if it needed new blinds I would have to send it to a pro shop anyway and I would have to carry that cost. If it can be repaired and it appears to be easy from doing the research, then it's the process of balancing the risk of doing damage and the cost of the potential repair versus the dopamine hit of learning new skills and about learning how the camera works, coupled with the time in a repair shop versus the immediacy of doing it yourself.

There are some things I would not touch, at least not without some practice... I'm not going to dismantle and service a coupled rangefinder on a Leica or attempt DIY open heart surgery!

It's not for everyone, but for those who might dare but are concerned about the risk of doing this job, I hope that I have given them the thumbs up that it can be done quite easily if you have the right tools... take advantage of me being stupid enough to take a risk and  having come out the other side of it safely.

By the way, it doesn't always turn out like this. I have planted a surfboard into a sandbar, smashed it and nearly drowned, by "bravely" going for the wrong wave and realising too late that I had made a mistake. I've had more than a few close scrapes like this when climbing or snowboarding or riding a bike... never learned my lesson. Not brave, not totally reckless, sometimes lucky.

[250swb]

1 hour ago, seneschal said:

The second blind is perfect. Shining an extremely bright CREE LED flashlight through the first blind I got this:

Here's the finished shutter, good as new in terms of being light tight. I cannot notice any difference in shutter timing... but will load another test FP4 and see how it goes. The real proof of the pudding will be ISO 3200!!! Not sure I dare try that until after I see the results with FP4.

I think 'good as new' should be reserved until you've done 50 films at least. People can either get it done professionally with known techniques of shutter curtain replacement etc, or try a home fix, the problem is if the home fix ends up costing valuable images in the long run it doesn't work. To be honest I'd try this if I had a hole in my shutter curtain, I've used other home grown methods successfully in the past, yet I wouldn't recommend anything until I'd tested it to death. Also not sure why 3200 ISO is the benchmark, have you just plucked a higher number out of the bag? If you want to test shutter integrity use a slow film (50 ISO Pan F for example) and long exposure times to see how much light comes through.

[seneschal]

I doubt I have enough life left in me to put 50 films through this body alone! If it still leaks or springs a leak again after a dozen films then I'll probably do the same repair... I'm pleased with it, the materials are great to work with and it was fun. It's not for everybody, but anyone who wants to give it a go and has the same degree of risk tolerance could easily try the same... with other materials and method possibly. I'm just sharing what I did and adding to our joint body of knowledge and experience in this forum. Yes, "I plucked ISO 3200 out of thin air", (to coin an idiom correctly), but I also happen to have 2 rolls left of that speed in hand which I have been using in another body playing with available light. Using a slow film and long exposure times is not the answer to testing whether the first curtain is light tight now. To do this you would need a fast film, wind on the film, take the lens cap off, leave it a couple of minutes, put the cap back on again, release the shutter and wind on again. Once the film is processed you will be able to see whether any light made it through the blind, it should be a blank frame. Using a fast film would be the best way to check whether light is getting through, as a slow film would not be affected as much. With a long exposure the blinds are open... I am not testing the opacity of the blind... maybe what you were suggesting is that this might be a way of checking the  accuracy of the shutter times themselves? I can certainly see this. Before I did this repair I shot a roll of FP4 at ISO 125 with the porous shutter. Quite a lot of latitude with this film, admittedly, but from the picture at the head of this post you can see that the exposure and therefore shutter speed is there or thereabouts. The light was not that changeable on that day, I was in a rush to shoot the film and get it sent off for processing, so I measured once and then guesstimated every other shot after the first. The test will be to see with the next roll how it performs now, if it doesn't leak and exposes correctly then it is good as new and good enough for me... for the time being... at least until it needs repair again. I'll put FP4 through it again... as a controlled experiment. I've never understood sarcasm or negative feedback, I'm not sure what anybody who trolls another on a forum is hoping to achieve. We are all different but are we not all ultimately on the same side?

[willeica]

I have used Deco Textil black paint to repair minor pinholes and it has worked, both on bellows and cloth shutters. I have only done this for minor pinholes and not for major repairs. I'll be interested to see any results from your camera after treatment with Pebeo. What you are doing is more than just closing holes, but rather you have applied a whole new surface. It should in theory work so long as the new surface holds together. I must mention the Pebeo products to my CLA guy who recommended the Deco Textil.

William

[seneschal]

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I put a roll of FP4 through it again yesterday. Very bright day! I have never been so nervous about leaving a lens cap off as I wandered round!

My bet is that I have missed a spot, either top or bottom of the blind and will have to have one more go. I did my best first time, checked with the flashlight round the edges, was pretty certain that I had got everything but the proof will be after I get the film processed.

The Pebeo Setacolor Opaque was incredibly easy to use, it dries perfectly matte and opaque and layers really thinly. I think the fact that it is specifically for painting on silk without changing or stiffening the draping characteristics of silk means it lends itself really well to this application. Light, flexible and opaque.

[seneschal]

Finally got the chance to compare the scans with the negatives from the roll of FP4 I shot after the blind repair. It seems I no longer have any leakage from the blind and the exposure across the whole roll seems pretty close to what I expected.

What I didn't expect is artefacts on the negatives that I was rather hoping were from the scanner and would only be on the scanned images... they're not.

Turns out that I had something(s) small poking it's(their) way into the edge of the frame. Very easy to see on this shot.

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So it looks like an old sliver of something hanging down near the film plane. I will have to take the case off the camera and have a proper look. It doesn't move across any of the frames, it's always present although less easy to see if that part of the photo is in shadow.

What a drag! I'll get there though... eventually.

At least the Pebeo works.

 

[seneschal]

And here it is, not the best photo in the world but amazing how close you can focus and the depth of field you can get with the tiny lentil on an iPhone, particularly if you use the flash. You can just about see the flake of old rubber that is the main „dangling“ artefact sticking up at the bottom of the shutter gate. Time to take the case off again and do a thorough inspection and clean.

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[PFM]

On 8/14/2021 at 7:37 AM, seneschal said:

And here it is, not the best photo in the world but amazing how close you can focus and the depth of field you can get with the tiny lentil on an iPhone, particularly if you use the flash. You can just about see the flake of old rubber that is the main „dangling“ artefact sticking up at the bottom of the shutter gate. Time to take the case off again and do a thorough inspection and clean.

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Yeah, that's the thing with eroding shutter curtains, the remains collect down in the channels.  I've used the fabric paint repair before on other cameras that weren't worth an expensive CLA by the pros, but from the condition of your curtains before the painting it might be better to replace them before they self destruct.  I've seen cameras before where only the second curtain was replaced (because it was the one usually visible) before the owner sold it.  You'd think anyone going to that much trouble would go ahead and do both, but then there are cheapskates everywhere.

PF

[rfaspen]

I used the Pebeo on a less porous curtain, IIIf BD, and it worked well.  However, I missed a spot and haven't had the energy to get it yet.  My IIIa gets nearly all my Barnack attention.  Just wanted to provide one more data point......Pebeo can work in right circumstances and proper application.

[seneschal]

On 8/27/2021 at 7:55 PM, PFM said:

Yeah, that's the thing with eroding shutter curtains, the remains collect down in the channels.  I've used the fabric paint repair before on other cameras that weren't worth an expensive CLA by the pros, but from the condition of your curtains before the painting it might be better to replace them before they self destruct.  I've seen cameras before where only the second curtain was replaced (because it was the one usually visible) before the owner sold it.  You'd think anyone going to that much trouble would go ahead and do both, but then there are cheapskates everywhere.

PF

I am sure it will eventually "self destruct" but maybe the Pebeo will hold the fabric together for a  bit longer before it needs to go for replacement. It's done nearly 70 years on its first set of blinds and only blind number 1 seems to have suffered degradation. I wonder why? Perhaps it was left on display, in the sun with the shutter cocked for a long period of time. That might also explain why the filter on the Summarit it came with was so filthy when I got it. Yesterday I found the time to take the case off again and thoroughly clean the channels. It now looks like there is nothing that will stick up, hang down or otherwise interfere with the frame.

I'll put another roll through it this weekend and see how we get on.

[seneschal]

On 8/28/2021 at 5:23 PM, rfaspen said:

I used the Pebeo on a less porous curtain, IIIf BD, and it worked well.  However, I missed a spot and haven't had the energy to get it yet.  My IIIa gets nearly all my Barnack attention.  Just wanted to provide one more data point......Pebeo can work in right circumstances and proper application.

I found the energy to take the case off and clean the debris from the frame yesterday. Feel lots better having done it! Go on! Your iiif BD deserves some TLC... take out 6 screws, slide a card down the back of the pressure plate, ease the case off and get your Pebeo out. Great way to make yourself feel positive and "re-energised". "Great minds think alike"... or is it "fools seldom differ" 😄?

[PFM]

On 9/10/2021 at 1:22 PM, seneschal said:

I am sure it will eventually "self destruct" but maybe the Pebeo will hold the fabric together for a  bit longer before it needs to go for replacement. It's done nearly 70 years on its first set of blinds and only blind number 1 seems to have suffered degradation. I wonder why? Perhaps it was left on display, in the sun with the shutter cocked for a long period of time. That might also explain why the filter on the Summarit it came with was so filthy when I got it. Yesterday I found the time to take the case off again and thoroughly clean the channels. It now looks like there is nothing that will stick up, hang down or otherwise interfere with the frame.

I'll put another roll through it this weekend and see how we get on.

My theory on that is it's due to the fact that the first curtain is usually wound up on the spool for extremely long periods of time, like when lounging around in the bottom of a dresser drawer, forgotten for years.  It seems to stress the coating much more than on the second curtain which is flat across the film plane.

PF

[Nick Dennis]

Three years on, May I enquire about how the shutters are holding up? I have a similar but not so extensive pin holing on my IIIc and this may be a route I could take initially to resolve.