30D and Rocket Blower?

How on earth can I get the dust off of the focussing screen?

Use the rocket blower again. It should dislodge the spec on the view finder.

snatiep wrote in post #4071755
How on earth can I get the dust off of the focussing screen?

If you blew it onto the screen, you should be able to blow it off.

Don't use the "sensor clean" option, since you don't want to lift the mirror and open the shutter. Just take the lens off and look above the mirror - that's the focusing screen. Fortunately, the focal plane of the screen is the bottom side, so you have it at your mercy.

Don't touch the mirror! It's delicate.

-js

yes, just use the blower on the mirror and on the focusing screen but make sure not to let it actually touch either of those. On a new camera, it's actually good that you're blowing out all this dust and particles sitting inside your mirror box. so keep at it and it'll be good soon.

snatiep wrote in post #4070177
Here is a cropped image I just took. It is from the upper right hand corner. Do you think the Rocket Blower would take care of this?

Thanks,
A very nervous new 30D owner!

I guess I am a whole lot pickier than many of you guys. This sensor is filthy. To get a better feel for how much is there, take a better, uniformly colored picture and un-focus as much as you can. If your taking the sky, set for manual focus and focus as close as the lens will go. You don't want nice focused clouds, but nice focused dust. Then in photoshop, use the "Auto Levels" function and the dust will pop right out. Even if the dust is not noticeable at lower f-stops, it is still doing it's damage in reduced IQ. Cleaning is so easy once you have been through the process once or twice. Anyway, here is the pic with auto levels applied.

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number six wrote in post #4070825
That's not much dust at f/22. You probably can't see it at larger apertures, right?

I'd call that a bit of dust for f22 especially all in one corner, it's a crop of a corner he said. I use f22 often for landscapes and macros.

It's easy to process so that dust and boogers are more obvious. I do that as a rule when looking for problems.

It's also easy to overemphasize the problem.

Here's my sensor, from an OOF shot of a blank monitor screen:

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Wish I could have responded to this one sooner, this happens and is why I stopped blowing mine out and informed all of our employees with cameras (which in turn I have to maintain and clean). I did this and the same thing, blew specks and what looked like an eyelash in and up over my focusing screen. It was a pain in the butt to remove and clean and once was enough for me. While I recommend that anyone can clean a sensor, I certainly do not recommend cleaning your own focusing screen. The clips alone are fragile and a pain to put back into place.

That's why I never recommend blowing any air (and certainly never use canned air, the propellant can fog the sensor requiring a scrubbing) into the camera body. Get yourself a visible dust brush or if that is too expensive, get the coppermine brush. I like the visible dust brushes because they are larger - I can clean the sensor and also wipe down the inside walls of the camera opening.

So, deal with the focusing screen dust (it won't affect your images) and get yourself a nice brush. Use the rocket blower to 'charge' your brush so that it sucks up the dust from a sweep on the sensor but for goodness sake, please don't blow air directly into your camera. There will be a lot of specks all around the inside and hard air blows it in there deeper. When you get tired of the dust on top of the screen, send it in for a cleaning - you might even get your first one free.

EDIT: I know a lot of people do use blowers and swear by them. If you're in a pinch and can't brush off or scrub your sensor, what are you going to do? My experience is dust blown will eventually get above the focusing screen so its not worth the hassle for me to remove the screens. I'm very particular about not seeing dust on the screen or the sensor. So I had to learn to clean the screens pretty quickly.

-John

snatiep wrote in post #4071717
Darn it!!!!!!

I just used the Rocket Blower and now there is a black speck when looking through the viewfinder. The Rocket Blower must have blown the speck up into the camera. I took a few pictures and the dust is still in the photos too.

bsmotril wrote in post #4069881
Your lucky, mine was filthy when new and required a thorough wet cleaning to get it anywhere close to six specks left.

Mine was disgusting when I got it. I really should have taken it back (I was pretty pissed).

For the $20 to mail it to Canon, I'l just let them clean the focus screen and sensor. I'll sleep better.

Since it is under warranty (I only got it last week) Canon won't charge me to clean it will they?

Thank You!