This topic feels a little out of place. I hope I'm not posting in the wrong spot. Everyone is talking about the latest developements and I want to know what makes an old camera die.
I have read the specs for some cameras, and have seen them proudly state that their shutters will last 100,000 or 200,000 actuations before failing. Well, I envisioned not working as being kind of boring. You push the shutter release and nothing happens. My situation was different. I thought my photos were getting a little soft so I took a look at the shutter and the sensor. The shutter has a small hole in it, and the sensor beneath the hole looks like it has smoke residue on it. Is this the normal way a shutter passes from this mortal coil? Did the sensor make the shutter too hot? Did the shutter generate the heat? Is this normal or must some obstruction had to have got inside between the moving parts. The camera is not dead (yet). It's not a big hole. It's not a good sign.
I did clean the smoke off of the sensor. Maybe the worst is over? I'll attach a photo if I can. Any information about this would be appreciated.
Thanks,
Arthur.
Just speculating, had the camera been pointed at the sun for too long at some point? That could burn a hole in the shutter. I can't imagine another way for such localised damage.
The cases of shutter failure I've seen are more mechanical in nature.
<a class="bbc_url" href="http://snowporing.deviantart.com/">dA</a> Canon 7D2, 7D, 5D2, 600D, 450D, 300D IR modified, 1D, EF-S 10-18, 15-85, EF 35/2, 85/1.8, 135/2, 70-300L, 100-400L, MP-E65, Zeiss 2/50, Sigma 150 macro, 120-300/2.8, Samyang 8mm fisheye, Olympus E-P1, Panasonic 20/1.7, Sony HX9V, Fuji X100.
Quote:Just speculating, had the camera been pointed at the sun for too long at some point? That could burn a hole in the shutter. I can't imagine another way for such localised damage.
The cases of shutter failure I've seen are more mechanical in nature.
Good suggestion Popo, Arthur, is the holed shutter made of metal? if it's steel I doubt if it's sun burnt, also could have been a short circuit , maybe a denuded wire briefly touched the shutter, that could explain the black deposits. let's see the photo! Strange.
The shutter seems like it is metal. I tried to attach a file but it said that the "flle upload failed" I posted a couple photos on Flickr, sorry for the hassle, but please take a look if you would:
https://www.flickr.com/photos/handsoff/14049330563/
https://www.flickr.com/photos/handsoff/14026136151/
I was thinking maybe a bug flew in when I was changing lenses and got fried on the sensor, maybe that would generate enough heat?
Oh, about the Sun theory: I was thinking that was a possibility as well. I use a 500mm mirror (Tamron SP 500 f/8) a lot. Also -and I am taking the stupidity bullet here so that some lucky reader might not have the same happen to them- I did sort of point a 135mm Takumar straight at the sun a while back. Not that long. It was a bright sunny day here in California. I wanted the catch the sun coming over the edge of a tall building to produce flare. Yes, everyone wants flare controlled, and I'm out trying to create it. That's me. I feel pretty foolish if that is what did it. On the other hand, that was over two weeks ago, and I use my camera every day (of course!) On the third hand I have been noticing light control and contrast problems...
Well it pretty much looks like the sun did the job then, I didn't think it could melt metal, maybe it's titanium or some other light alloy with not such a high melting point, it was relatively well know with cloth focal plane shutters though.
It's a lesson for all of us!
Quote:Oh, about the Sun theory: I was thinking that was a possibility as well. I use a 500mm mirror (Tamron SP 500 f/8) a lot. Also -and I am taking the stupidity bullet here so that some lucky reader might not have the same happen to them- I did sort of point a 135mm Takumar straight at the sun a while back. Not that long. It was a bright sunny day here in California. I wanted the catch the sun coming over the edge of a tall building to produce flare. Yes, everyone wants flare controlled, and I'm out trying to create it. That's me. I feel pretty foolish if that is what did it. On the other hand, that was over two weeks ago, and I use my camera every day (of course!) On the third hand I have been noticing light control and contrast problems...
It is a bit odd still. Indeed, it looks like as if the sun has been allowed to burn a hole by laying around without lens cap. However, the mirror assembly is in front of the shutter, directing most of the light upwards to the view finder, and a bit down to the AF sensor. Only mirror lock up could cause this?
Anyway, see if you can clean the smoke residue with a good wet sensor cleaning system. And let the shutter be replaced, i guess.
I don't think anything could have fried on the sensor, as you can't actually reach the sensor from the front without passing through more optical filters.
I have to wonder if the sun could still be the culprit. The mirror will reduce the intensity, but as it isn't focused on the mirror itself that wont take the worst of the heat. If anything, perhaps a slight misfocus at the time would make the shutter a more likely target? If the sun were in perfect focus on the sensor, even the small distance to the shutter would give a defocus effect and may reduce the chances of it burning.
Given all this, I have to say I've shot directly at the sun with various lenses before without ill effect. I did try to keep the duration the sun was in view to a minimum though. Maybe a longer period is required.
<a class="bbc_url" href="http://snowporing.deviantart.com/">dA</a> Canon 7D2, 7D, 5D2, 600D, 450D, 300D IR modified, 1D, EF-S 10-18, 15-85, EF 35/2, 85/1.8, 135/2, 70-300L, 100-400L, MP-E65, Zeiss 2/50, Sigma 150 macro, 120-300/2.8, Samyang 8mm fisheye, Olympus E-P1, Panasonic 20/1.7, Sony HX9V, Fuji X100.
Quote:I don't think anything could have fried on the sensor, as you can't actually reach the sensor from the front without passing through more optical filters.
I have to wonder if the sun could still be the culprit. The mirror will reduce the intensity, but as it isn't focused on the mirror itself that wont take the worst of the heat. If anything, perhaps a slight misfocus at the time would make the shutter a more likely target? If the sun were in perfect focus on the sensor, even the small distance to the shutter would give a defocus effect and may reduce the chances of it burning.
Given all this, I have to say I've shot directly at the sun with various lenses before without ill effect. I did try to keep the duration the sun was in view to a minimum though. Maybe a longer period is required.
As have I, a strange one, even the shutter would be in front of the focal plane reducing the heat concentration and the hole was quite a decent size and it is at the upper part of the shutter, with the image inversion the hole would be in the lower half (from the sun) and as you say behind the mirror.......... hmmm... in live view the shutters open, even with a long exposure the shutters open and leaves only the short time between the mirror rising and the shutter opening......with the mirror in lock up the camera would be on a tripod, a long wait before the exposure maybe with the sun in the lower frame or in portrait? that's really the only way! would you forget to mention mirror up on a tripod?
seriously weird, maybe I'm back to my electrical theory, or not!
04-28-2014, 05:28 AM
(This post was last modified: 04-28-2014, 05:40 AM by Arthur Macmillan.)
You know what they say? I little knowledge is a dangerous thing! It's like this...a guy I met at an open air market looking at used camera lenses and I got to talking. He had managed to get some spectacular flairs by shooting wide open in the direction of the sun. He described how he did it, and he showed me a couple examples on his iPhone. They were very unusual...one part was the shape of a square sheet draped over a sphere but elongated as though pulled at on the corners. There was another part that was like a diamond with one corner stretched out, so it was like a long spear head. Part of the recipe was to use a lens that was not fully coated. Such as the 135mm Takumar.
Before I tried it I wanted to find out if it would harm the sensor. I normally am pretty careful with my camera. So I read some about the subject, and it seemed as though the sensor was considered capable of withstanding very high temperatures. But someone was worried about people risking there eyesite looking at the sun. So I thought why not try to aim in live view, so that I wouldn't be looking in the sun. Well, this wasn't such a great idea. I have never used live view before in a situation where I was not glad to have the exposure of the screen normalized they way it does when it normalizes a view that would be too dark for you to focus or frame your subject. Without getting into details, as far as I could see live view does not know how to present either the sun, nor the vicinity when it is aimed in the general direction of the sun. It didn't take me too long to figure that out. But, yes, there was a tripod, and yes the mirror was locked up for live view. The shutter should have been open, except when the mirror was down. I don't think I would have been using mirror lock-up alone.
I'd like to think I didn't do anything really stupid to cause this, but failing that, I'd like to learn something from the experience so that I don't do it again.
I'm very grateful for your comments. I feel a sort of kinship with those of you who have shared their thoughts, especially because I believe you know a great deal. I was afraid as a humble Rebel user I would find myself being asked to step to the back of the forum. But I may have to put your patience to the test one more time in order to try to understand this.
I gather the sensor produces quite a bit of heat when it is...sensing. What condition causes the heat? For instance, it is not unusual to have a long exposure, but normally this would only happen when there was not much light hitting the sensor. The shutter is open longer, but the total amount of light is fairly consistent. We can add 2 or 3 EV's. Using manual exposure we could keep the shutter open for 30 seconds even in a bright setting. My question is does the sensor get hotter when exposed to a very bright light for a period of time than it would if it were exposed for the same amount of time in a low light setting. Could the sensor get hot enough to melt the shutter if exposed for a long time to normal light?
There is a reason I ask, other than the ill-fated flare shoot. But if that can't happen I'll spare you the details.
Disclaimer:
-When I say cleaned the sensor, or expose the sensor I mean the filter over the sensor. That is what appeared smoked, and that is what I cleaned. It seemed to clean up well. Today I shot about 250 photos the majority of them outdoors since cleaning the sensor last night. The sensor/filters look clean still, and the shutter doesn't look any worse.
I should go through my photos for some clues. Sorry, about my impatience. It's hard on me because I don't know enough about the way the camera works to make an intelligent guesses.
-Arthur
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