Photoshop Creative

I suspect there may be dust on my sensor. I have a recommendation for a shop who does a good job of cleaning sensors, but I would like to test myself how much dust there may be. I have read somewhere which kind of picture I should take to make this problem obvious. If I remember well, the subject should be clear and out of focus? Any idea?

Michel,

Clear, out of focus, so a sky shot, and slightly over-exposed - but try an exposure bracket.

Before giving it over to the pros, have you tried something like this?

http://www.henrys.com/webapp/wcs/stores ... emID=98951

I have a similar contraption and have found that setting it up on my tripod with the body pointing down and a few short shots of air has dislodged everything to date.

Here's a thread on dpreview that tells how to check.

http://forums.dpreview.com/forums/read.asp?forum=1034&message=13363346&q=how+to+tell+if+dust+on+sensor&qf=m

Thanks very much, John!
I'll try this kind of test shot. I'll do a search for your air blowing solution; I think there should be little risk in this operation.

Michelle,
Thanks for the link! I can only see suspected spots on clear skies with wide aperture, especially if I play heavily with levels or such, and it is rare enough to be treated easily by Elements. Anyway, it is good to know I could resort to a trustworthy shop in case of need.

Michel,

When I got my first sensor dust, I was about 1 year into the camera and was in a dither. I took the camera back to the place I bought it from (Henrys - like the link I posted) and asked what could be done. The clerk took off the lens, peeked in and said Yes, it's dust.

I asked what could be done and he went and opened up the blower I eventually purchased and showed me how to use it. I was free and clear for about another 6 months, then got it again. I tried the tripod trick and just to make sure, I used my fingers to only allow about about 1 inch (2 cm) to get into the camera body. Two squeezes of the bulb and problem gone.

One thing is to set the camera up for sensor cleaning. The image below is from the canon manual for the 20D:[

attachment=0]ScreenShot00112.jpg[/attachment]

P.S. You can download the English or French version of the 20D manual in PDF format from the Canon Canada web site. I have done that for my 30D and usually find it a lot faster then thumbing thru the Canon User Manual. French version here - http://canoncanadafr.custhelp.com/ci/fa ... 1139950418

I have the exact same "rocket blower", linked in John's post. I will no doubt reach the point of paying somebody to "scrub stuff off" but, so far, this blower has always done the trick. And.... at around fifteen bucks or so, you sure can't beat the price.

Never thought of putting the camera on the tripod. Well, duh -- that sure works better than holding the camera in one hand and the blower in the other

Rusty

Bear in mind you are not really cleaning the sensor, but a glass filter over the sensor for protection. Moose Peterson has an excellent tutorial on his site for how to clean. I have been cleaning my camera sensors for years. it is quite easy.