Bkplant |
Exposure Problem Hi there! I am relatively new to manual photography and have encountered a problem already. Perhaps someone can help me out. I recently purchased a used Rolleiflex SL35 with a 50 and 70 mm lens. I shot my first roll last week but about half of the photographs came out with a shadow on the right side, about 1/8th of the print, as though they have been underexposed along the edge. I noticed that some have this quite bad, while others have a slight tinge of it. One vertical picture has it on the bottom, while all the other pictures, taken horizontally, have it on the right side. I am curious if anyone might know what this is. I was using 200 kodak gold film, the proper ASA setting, good light and seems like the proper aperture and shutter speed settings as, aside from the edge, the exposure of the rest of the prints look fine. I have 2 ideas so far: one that light was coming in through the eyepiece. I have no eye cup on it. Two: it has something to do with the shutter speed. I had the camera checked out at a shop after I bought it and they said that the shutter speeds were fast on the higher settings and could use adjustment. I don't know if a fast shutter would cause this problem, as no flash was involved and light was good that day.
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John A. Lind |
Hi, I presume this problem is without flash using only available light. If so, this sounds like "shutter capping." A focal plane shutter has two curtains. When the shutter is fired, the first (opening or leading) curtain is released. After a delay, the exact time for which is determined by the shutter speed selected, the second (closing or trailing) curtain is released. The shutter curtains always travel at the same speed, regardless of the shutter speed selected. Shutter speed is changed by changing the time delay between releasing the first and second curtains. At shutter speeds faster than the X-Sync speed (the one used for flash), the second curtain is released before the first one has completely traveled. [This is why the X-Sync speed, or slower, must be used with flash.] At the faster shutter speeds, the delay becomes so short that the film is exposed by a slit traveleing across the film gate. If the opening curtain starts to slow (or even stops) before its end of travel, the closing curtain will start to catch up to it resulting in the "slit" becoming narrower near the end of shutter curtain travel and the portion of film near the end of shutter travel receives less exposure than the the rest of the frame. If the "capping" is severe enough, the second curtain completely catches up with the first one resulting in a completely unexposed strip at a frame edge. Shutter capping is most often found in older cameras with heavily used shutters. The problem is usually the weakening of the spring[s] that pull the opening shutter curtain across the film gate, but it can also be the opening curtain binding slightly near the end of travel. Have the shop check it out specifically for shutter capping. If they have the equipment to test shutter speed, they should be able to set it up to test for capping near the end of travel. You can also run your own test. Evidence of capping in the print (the underexposed strip near the edge) is almost always more severe at higher shutter speeds than lower ones. Run a roll of film through, use various shutter speeds and make note of what shutter speed was used for which frame. Then look to see if the problem is worse at the higher shutter speeds. On most cameras it can be fixed by adjustment of the spring tension on the shutter curtains, or by cleaning the shutter curtain mechanism, or both. Note: -- John
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Bkplant |
Thanks for that well written response. It sounds like you have the problem dialed. I took it to a shop and they said the same thing. A shame really as the repair estimate is too high for it to be worthwhile to fix. I will have to stick to shutter speeds of 125-250 or less as I think the 500 setting was causing the problem. I guess this is something I will need to really watch out for when buying older used slr's. I guess it pays to have it checked out first, regardless of the asking price.
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John A. Lind |
Byron, How I was nearly certain about the problem? Been there, done that with a nearly 50 year old Zeiss Ikon Contax IIIa that was capping at the top speed of 1/1250th and occasionally at 1/500th. A collectable, it was worth having a complete shutter overhaul. It's a pleasure to use these old gems! The cost for fixing will vary from shop to shop. Since it's a Rollei (I also have a Rollei 35S), I know of one or two shops that specialize in them. Contact me off-forum and I'll send you the names of one or two people to contact that specialize in cameras like yours (and have an excellent reputation among the collectors of them). You should be able to get a ballpark cost from them for a shutter overhaul and can make some decisions from that. (Typically firm estimates are only made after actually looking at the camera.) My name below this with the date next to is hyperlinked to my page here. Go to my page and use the "Contact" button below my picture on it to send an email directly to me. It will contain your email address when I receive it, as if you had sent it to me directly. -- John
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Connie Campbell |
WOW! I just posted a note about this exact same thing.....but my "black strip" happens when I use the flash. But I think John just nailed it for me! I use only shutter speeds of 125 and 250 so I think until I can get a new camera or pay for repair I wont use flash photography! Thanks to Byron for having a problem and to John for answering! Now I am not so confused! Connie
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John A. Lind |
Connie, You may have an entirely different problem if this occurs *only* when you use a flash. There are two primary causes for the symptoms you describe. First: The reason is how focal plane shutters work. It consists of two curtains, an opening (first) curtain and a closing (second) curtain. The curtains *always* travel at the same speed across the film plane. Shutter speed is controlled by changing the amount of delay time between releasing the two curtains. Set a shutter speed fast enough and the closing curtain is released *before* the opening one has fully traveled. At speed such as 1/1000th or 1/2000th, it's more like a narrow slit traveling across the film plane. The X-sync speed for a focal plane shutter is the fastest shutter speed at which the opening curtain fully travels *before* the closing curtain is released. The flash is fired by the camera between while the film plane is fully open. Newer cameras have faster traveling shutter curtains, and they are more vertical ones than before (vertical shutters travel a shorter distance [2/3 that of horizontal ones]). Second: -- John
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