Isaac Brooks Posted November 10, 2010 Share Posted November 10, 2010 Hi, I have a new SBM factory-coverted Super 16 body. I've discovered that the aperture plate on these new cameras is black and not as scratch-free as the older ones (with the lighter shade of color). In fact, just from cleaning with an orangewood stick, it got roughed up. Anyone feel the same about this? Does anyone know if this might yield abrasions on the film itself? It seems unlikely to me, as it took so little to scratch it. About to shoot some stock for a Spirit Scan - so I suppose testing this would be a good idea. Opinions about this are very welcome though. Thanks! Isaac Link to comment Share on other sites More sharing options...
Robert Lewis Posted November 10, 2010 Share Posted November 10, 2010 Hi, I have a new SBM factory-coverted Super 16 body. I've discovered that the aperture plate on these new cameras is black and not as scratch-free as the older ones (with the lighter shade of color). In fact, just from cleaning with an orangewood stick, it got roughed up. Anyone feel the same about this? Does anyone know if this might yield abrasions on the film itself? It seems unlikely to me, as it took so little to scratch it. About to shoot some stock for a Spirit Scan - so I suppose testing this would be a good idea. Opinions about this are very welcome though. Thanks! Isaac I am not sure what you mean by the term "aperture plate", but I am wondering whether you are referring to the pressure pad which is made of "plastic" and is black. In any event, there is a serious risk that anything which comes into contact with the film which is scratched will, in turn, scratch the film. Even the finest of scratches can do this. I think, therefore, that you are going to have do a test film. One thing you can do, I think, is to do the test in two parts. Part one: as the plate or pad is at the present time - this will tell you whether you have a problem at all. It just could be that that the scratch you have will not cause scratching of the film. Part two: After smeering the pad or plate with some natural skin oil taken from the side of your nose. Run a clean finger down the side of your nose and gather a little natural oil from the surface. Then smeer the oil on the plate or pad. This is an excellent lubricant which will not affect the film, but it does most effectively lubricate the surfaces between which the film must pass. Part two of the test will tell you whether, if Part one shows you have scratching, lubrication is sufficient to overcome it. Frankly, if you have scratching of the film which shows up in Part one of the test, I have some doubts whether lubrication will overcome it. If, however, you are referring to the plate which forms part of the gate (the plate with the aperture cut into it), then much of what I say above is relevant. I haven't seen a black plate - only the light ones, but it occurs to me that the fitting of a "black plate" is associated with the conversion of the camera to S16. If that is scratched and the test shows that it is scratching the film, then you could be into replacing the plate, and if it was a factory conversion it might be you are best advised to send the camera to Bolex for attention. Best of luck. Link to comment Share on other sites More sharing options...
Jean-Louis Seguin Posted November 10, 2010 Share Posted November 10, 2010 Hi, I have a new SBM factory-coverted Super 16 body. I've discovered that the aperture plate on these new cameras is black and not as scratch-free as the older ones (with the lighter shade of color). In fact, just from cleaning with an orangewood stick, it got roughed up. Anyone feel the same about this? Does anyone know if this might yield abrasions on the film itself? It seems unlikely to me, as it took so little to scratch it. About to shoot some stock for a Spirit Scan - so I suppose testing this would be a good idea. Opinions about this are very welcome though. Thanks! Isaac When you say scratches, you have to be more specific. Emulsion-side and base-side scratches are caused by different factors. The "black" aperture plates are made of steel and should not be easily scratched with an orangewood stick. In any case, the plate only come in contact with the emulsion outside the negative area. If properly machined, this should not be a cause of scratching. It doesn't really matter whether they are steel or anodized aluminium like the later, light colored ones. Scratches in the perf area are sometimes visible because of the claw design. Again, this is not part of the exposed negative. The pressure plate, however is another matter. First, they are not and never were plastic. They are made made of highly polished aluminium, hard-anodized, black on the earlier ones and light colored on the newer super-16 ones. These are contact with the base side across the whole width of the film. They must be cleaned frequently to prevent accumulation of debris that could cause base-side scratches. However, I have noticed that the newer super-16 type pressure plates supplied by Bolex do not seem to be as "hard" as the original ones and may get damaged more easily. Cheers, Jean-Louis Link to comment Share on other sites More sharing options...
Robert Lewis Posted November 10, 2010 Share Posted November 10, 2010 I have a great deal of respect for Jean-Louis, and willingly acknowledge his expertise. He is one of those guys one is very happy to have around. I have not seen a black aperture plate notwithstanding that I have a number of Bolex 16mm cameras. All of my cameras are fitted with the light anodised aluminium plate. As to the pressure plate, one learns something every day, as they say. I appreciate that the basic structure is metalic and appears to be anodised or finished in black. However, I would ask to be excused if the plate iteslf is anodised aluminium. It does seem a very highly polished and hard black finish which has all the appearance of being a "plastic" material or coating. That having been said, Jean-Louis is the expert, not I, and if Jean-Louis says it is anodised aluminium, then that is what it is. I return to the central point of what I said, however. If you suspect that any scratch you might have caused comes into contact with the film, to be certain that it will not scratch the film you need to run a test film. You can then do a visual check perhaps with a magnifying glass. You don't necessarily need to use unprocessed film for this purpose. If you put a length of unmarked film through the camera, you should be able to see whether any scratches which were not on the film before you did so have appeared and whether any such scratches as might have been made on the film as result of running it through the camera are significant. I hope all is well. Link to comment Share on other sites More sharing options...
Isaac Brooks Posted November 10, 2010 Author Share Posted November 10, 2010 I am not sure what you mean by the term "aperture plate", but I am wondering whether you are referring to the pressure pad which is made of "plastic" and is black. In any event, there is a serious risk that anything which comes into contact with the film which is scratched will, in turn, scratch the film. Even the finest of scratches can do this. I think, therefore, that you are going to have do a test film. One thing you can do, I think, is to do the test in two parts. Part one: as the plate or pad is at the present time - this will tell you whether you have a problem at all. It just could be that that the scratch you have will not cause scratching of the film. Part two: After smeering the pad or plate with some natural skin oil taken from the side of your nose. Run a clean finger down the side of your nose and gather a little natural oil from the surface. Then smeer the oil on the plate or pad. This is an excellent lubricant which will not affect the film, but it does most effectively lubricate the surfaces between which the film must pass. Part two of the test will tell you whether, if Part one shows you have scratching, lubrication is sufficient to overcome it. Frankly, if you have scratching of the film which shows up in Part one of the test, I have some doubts whether lubrication will overcome it. If, however, you are referring to the plate which forms part of the gate (the plate with the aperture cut into it), then much of what I say above is relevant. I haven't seen a black plate - only the light ones, but it occurs to me that the fitting of a "black plate" is associated with the conversion of the camera to S16. If that is scratched and the test shows that it is scratching the film, then you could be into replacing the plate, and if it was a factory conversion it might be you are best advised to send the camera to Bolex for attention. Best of luck. The aperture plate is the piece that essentially has the gate cut into it and which faces the pressure pad - the pressure pad is fine so far and is scratch free. Link to comment Share on other sites More sharing options...
Chris Millar Posted November 10, 2010 Share Posted November 10, 2010 The pressure pad is certainly alu - running mag stripe film will grind itself through the black and reveal the metal soon enough :lol: Link to comment Share on other sites More sharing options...
Isaac Brooks Posted November 10, 2010 Author Share Posted November 10, 2010 When you say scratches, you have to be more specific. Emulsion-side and base-side scratches are caused by different factors. The "black" aperture plates are made of steel and should not be easily scratched with an orangewood stick. In any case, the plate only come in contact with the emulsion outside the negative area. If properly machined, this should not be a cause of scratching. It doesn't really matter whether they are steel or anodized aluminium like the later, light colored ones. Scratches in the perf area are sometimes visible because of the claw design. Again, this is not part of the exposed negative. The pressure plate, however is another matter. First, they are not and never were plastic. They are made made of highly polished aluminium, hard-anodized, black on the earlier ones and light colored on the newer super-16 ones. These are contact with the base side across the whole width of the film. They must be cleaned frequently to prevent accumulation of debris that could cause base-side scratches. However, I have noticed that the newer super-16 type pressure plates supplied by Bolex do not seem to be as "hard" as the original ones and may get damaged more easily. Cheers, Jean-Louis Hi Jean-Louis, The scratch is not deep, it looks as though the finish on the plate has been irritated. It all got started when I was trying to get rid of some emulsion w/ the orangewood stick. At first I thought the scratch was just this stuff getting spread around, but it looks like the plate is a little scratched. Thoughts? Isaac Link to comment Share on other sites More sharing options...
Jean-Louis Seguin Posted November 11, 2010 Share Posted November 11, 2010 Hi Jean-Louis, The scratch is not deep, it looks as though the finish on the plate has been irritated. It all got started when I was trying to get rid of some emulsion w/ the orangewood stick. At first I thought the scratch was just this stuff getting spread around, but it looks like the plate is a little scratched. Thoughts? Isaac The black aperture plates have chrome plated side rails. The chrome plated rails do come into contact with the emulsion but outside the picture area. The black part of the aperture plate does not come into contact with any part of the picture area. If the black part is scratched, it will not cause a scratch to the picture. During the conversion, as done by Bolex, the original black part of the steel was probably fading and was re-blackened by a chemical process. This blackening is only superficial and can be worn off by rubbing which is probably what happened in this case. Cheers, Jean-Louis Link to comment Share on other sites More sharing options...
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