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Dirty Sensor on EOS20D


I took the plunge and bought the EOS 20D last Wednesday. It's a great camera and have been pleased with it. I have been very careful with it. Yesterday morning, I noticed a 'speck" on the viewfinder and I tried to blow it off. It did not work, I took it to the local camera shop here ( Samy's Camera ) and showed it to the repair guy. He opened the lens and cleaned it up for me using blower and brush. When I looked it at, it looked worse!! I ended up with more "dirt" than I started. I read up on books on how to clean the sensors and even used the "swabs". It's still dirty. I am going to bring it to the Canon Service Center tomorrow and hope it works!! My camera is less than a week old. Gimme a break!
>If the camera is less than a week old then the first stop should have been >either Canon or a Canon accredited repair facilty .Nowhere else ...

Yes I agree, you should take it back and complain but what a pain and trauma. This is one of the things which puts me off the idea of DSLRs. It is a problem which the manufacturers really need to sort out. Only Olympus so far has really addressed it.
I just came back from the Canon Serrvice Center in Irvine. It is appoximately an hour drive from L.A. They checked it and said that they have to replace the "soiled" focus screen on the camera. The focus screen is on back order and I have to wait for at least two weeks. Meanwhile, they recommended that I take it with me and shoot pictures, as this wont' affect the picture quality.
John, I realise from reading other forums that this is an issue on DSLR's.
If the dirt is on the focusing screen and it requires sending to the shop to change or clean then that's a camera-specific design issue, not a generic DSLR issue.
The problems I have heard about have been from dust on the sensor itself as I understood it. I have found the focusing screens on film SLRs to be very difficult to clean once they get dirty and I have always been wary of blowing compressed air at them in case the dust gets into the works of the camera. I suppose it's the same with a DSLR and maybe blowing at the dust will get it on to the sensor.
Perhaps the camera is so new that the service centre didn't yet have supplies of screens in stock but I'm surprised that you can still focus without a screen. I suppose you can use the LCD screen?
I guess I'm spoiled because every serious camera I have owned that I can remember had a removable focusing screen, so cleaning was never an issue.
I took pictures today ( with dirty focus screen ) and it's working fine. Other than the annoying cloudy, dirty viewfinder:-( Actually, with the EOS20D , the LCD screen is not used as viewfinder.
Sorry Ren,
I hadn't realized that they'd left the old screen in the camera pending replacement nor that the LCD didn't act as an extra viewfinder. Glad it's working OK though.

I find cleaning a screen difficult even where it's replaceable. Even with the special tweezers to remove it, I tend to scratch it and find it difficult to get dust off and then I may well get a finger mark on it. Then it's a new expensive screen and the problem of inserting it without damaging the new one as well. Consequently I tend to leave well alone nowadays. I expect that it is just clumsy me.
> [I assume what really got dirty was the focusing screen rather than the CMOS sensor based on your context. That said, the focusing screen won't affect the picture quality although, depending on how dirty it is, it can throw off the expsoure some. The focusing screen is micro-etched and really should never be cleaned with a swab, brush, or the like. You can use compressed air, just make sure you don't shoot any fluid out. If it is really soiled (but not scratched) you can sometimes clean it with an ultrasonic cleaner and/or flushing with reagent grade cleaners. This requires removing the screen, which really should only be done by a competent service center. The easiest is to replace the screen.]