## Canon Image Challenge 21 - Energy ##

Started Aug 6, 2010 | Discussions thread
JimH Forum Pro • Posts: 12,901
Re: I'm pretty lazy about it, but...

sparkey2 wrote:

When you say "cotton swab" Do you mean run of the mill Q-tips or even possibly cotton balls?? If so do you have problems leaving cotton fibers behind when you use them?

Paul A.

Yes. Just Q-Tip type swabs.

They will shed fibers sometimes, but usually, the fibers are so enormous that they're easy to blow out of the mirror box. I've had them get stuck between some tight-fitting pieces on occasion, though, so I had to then yank them out with tweezers. But that's pretty rare and it's easy enough to remedy anyhow.

But I don't like the really high-quality swabs because they're wound so tightly that they don't have any "give" to them and thus, they cover a very tiny surface. I actually like some of the really low-end swabs because they're even looser and more "fluffy", so they cover a larger swath with each pass. Kind of like a large mop head

I breathe into the mirror box, then swab the moisture off of the sensor filter, then I follow that up with a blast from the canned air to get out any loose particles. It usually works great on the first try and takes only a few seconds.

The one thing I'm careful of, though, is to get a fresh box of swabs and open it in a relatively clean area, being careful not to touch any of the swabs with my fingers and then I dump them immediately into some ziplock bags. That way, when I want one, I know it'll be clean.

The thing I fear most is some kind of hard grit either on the swab or on the sensor filter such that it gets drug across the filter, scratching it or its coating.

So I usually blast the sensor off well with the canned air as the very first step. Then I do a dust check. Then, only if needed, I proceed with the swabbing, and then I check again.

To test for dust, I use a lens set to f/32 and the pop-up flash on the camera and my favorite milk-jug diffuser. I focus the lens to infinity and get about four inches from a white or light-colored, uniform surface and shoot.

I then simply check the image on the back of the camera, zooming in fairly deep and "panning around" to see the whole image eventually. That way, I don't have to mess with transferring files to a computer, etc. So the whole dust test takes only a few seconds. If it still has some dust, I just take the lens off again and have another go at it.

I don't ever use autolevels on a computer to test for dust. I just take a plain shot using normal settings, and review it on the back of the camera. It's fast, reveals anything that will actually show up in a real life photo, and doesn't drive me nuts chasing nits that would never be a problem in real shooting.

The thing that makes me need to clean more frequently than most people is usually macro shooting at very tiny actual or effective apertures. At larger apertures, you can live with a fairly dusty sensor filter.

-- hide signature --

Jim H.

Post (hide subjects) Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow