Doug Pardee Offline Image Upload: Off
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p.2 #3 · Cleaning 5D Sensor - Need Help! | |
Cableaddict wrote: this is the first I've heard that the LPF was put it backwards, though that could certainly be. Is this verifiable?
No, because that was just some early speculation before people understood that the 5D sensor was the first one that Canon had made that didn't have a glass cover.
In the earlier sensor stack designs, the frontmost layer was a glass cover with a dichroic IR-reflective coating on the back. The coating was toward the rest of the stack and thus protected. Occasionally Canon had been known to get this cover on backwards, with the dichroic coating exposed.
With the 5D, Canon saved some money by getting rid of that glass cover and coating the front of the frontmost low pass filter with the dichroic coating. This is clearly described in Canon's White Paper on the 5D. So on the 5D, the camera is designed to have the dichroic coating exposed. (All of the dust-shaker cameras, too.)
What I read was that Canon used a different material for the coating.
That was more speculation, and possibly correct but my guess is probably not. According to Photographic Solutions, maker of Eclipse fluid, Canon says that the issue is "a result of a variance in the coating on the surface of the image sensor of the EOS 5D." So the question is what do they mean by "a variance"? Is it a change in material, a change in thickness, a change in processing, or…?
Dust-Aid quotes a company that does coatings: "It is possible for coatings to be weak if, during it's lamination process, insufficient heat was applied to the coating or if the surface of the glass was not prepared properly. This weakness in the coating could easily lead to bond failure when cleaned."
Dust-Aid also says that Canon Factory Service claims that "all of Canon's low pass filters are made the same so there is no difference between them" to which Dust-Aid says, "we do not agree with Canon's statement that all of their low pass filters are made the same." (linked page)
Either way, is there any documentation as to what serial numbers are in question? My 5D is second generation, I believe, ser # 2221 200093.
It's not clear to me that it really is a matter of serial numbers. Photographic Solutions originally said that it was only a problem on early production 5Ds, but has removed that statement from their page linked above.
Dust-Aid believes that there is a visible difference between the low-pass filters, and provides photos on their page linked above. I can't tell if they're right about that, either.
I am petrified of swabbing it, even with Eclipse, until I know for sure.
Photographic Solutions will pay for any damage if you follow their directions, including using Sensor Swabs instead of Pec*Pads, and if you send the damaged camera to them instead of directly to Canon.
Dust-Aid says on their page linked above, "If you discover that you have a below standard coated filter from Canon, which Dust-Aid has de-coated, we will replace the filter for you."
Edited on Jun 30, 2008 at 04:40 PM
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