Cleaning a camera lens

My camera photos have picked up some dark circles. They seem especially pronounced when I use the zoom function, which seems to focus on these dark spots and make them more distinct.

I love to take photos but have never actually taken a class or learned photography rules. My camera came with some kind of cleaning cloth but this seems insufficient. I have a strong suspicion that this isn’t one of those learn by doing type of things, and that if I try to clean the lens by trial and error that I could scratch it. So:

  1. What’s the best, cheapest, easiest way to clean my camera lens?

  2. It kind of seems like in addition to the dust and oil on the main exterior lens, that there might be some dirtiness to the interior lens - how do I clean that? Can I disassemble my camera easily and clean it myself or do I need to take it to some expert? If so so where? Camera shops don’t seem to exist anymore… But I don’t want to rack up a huge fee at a place like Best Buys where I would think the fee might equivalent to a substantial down payment on a new digital camera. What is my best option there?

It it’s a good lens, take it into a camera shop for a professional cleaning. It’ll cost a few bucks but it’s worth it to not make the problem worse, which I’ve seen people do when they try to clean the internals of their own lens. There are still camera shops that do this in most cities of any size, but they are getting harder to find.

I had a similar problem a few years ago. But it turned out to be dust on the sensor, not the lens.

This is most likely the problem you are experiencing. Dust on the lens is too close to ever be focused enough to cast a shadow.

You could try blowing the dust off the sensor with one of these first.

It would be useful to know what kind of camera it is.
Dust on the sensor will appear more distinct if you stop down (use a small aperture, highest f stop available). If the spots vary in appearance not with aperture, but actually with zoom/focus differences, then I’d think the issue is in the lens somewhere. Grunge on the front element is rarely focused enough to see and isn’t very likely to be the problem.

This. I would have to see the picture and what you mean by dark circles, but dust or other imperfection in the lens usually creates more general, widespread artifacts like blurriness in areas of the photos, haloing, unacceptable light “bleeds” in high contrast areas, etc.

If you see dark circles that look like spots, that is definitely dust on the sensor. At lower aperatures (f/5.6 and below) it will look like a fuzzy, out-of-focus blotch. As you get to higher and higher apertures, it will become more distinct and pin-point. When you get to f/16 or f/22 it should look like a hard, black dot (or even a curved line if you got a hair or thread in there.)

As for cleaning the lens, cleaning the internal elements really is a professional’s job. Or perhaps an experienced hobbyist. I photograph for a living, I like to tinker with things, but I would never attempt to take apart a lens to clean it. That goes to the camera shop. As for outside elements, I first use a blower of canned air to get out any large particles, then lens cleaning solution onto a microfiber cloth, and gently clean the lens with it. The rear lens element (closest to the camera) is the most important one, optically, as it’s closest to the focusing plane. Any dust or imperfection there is much, much more noticeable than the front element.

This is an example of dust on the sensor of my D-SLR:
Imgur
Easily fixed using the the little gadget that UncleRojelio linked to, although you need to know the menu functions on your camera to get into cleaning mode (i.e. flipping the mirror up and having it stay there).
Hope that helps.

ETA: it was a fairly big speck of dust that caused that. Whatever you do, don’t touch your sensor with anything at all. Only use a blast of clean air.

Sometime air won’t do it. I have to wet clean my sensors every two months or so with Pec Pads and sensor cleaner solution. A blast of clean air often won’t do it. Also, canned air is generally not recommended for this application, but rather one of those little blower brushes. The reason is sometimes you get a blast of propellant (or whatever that wet stuff is that comes out of canned air when blasted at weird angles), and you don’t want that on your sensor.

That said, your not actually cleaning the sensor. Atop the sensor in almost all cameras is an anti-aliasing filter, and that’s what you’re cleaning the dust off of. Sure, you don’t want to scratch this, but sensor cleaning isn’t quite the dangerous delicate operation people make it out to be. Just be careful, use common sense, and you’ll be fine. But do try the air cleaning methods first.

Canon PowerShot SD800IS. Not a super expensive camera, and I’ve had it a few years, so I don’t want to spend mucho mula just to get it cleaned, but I don’t have quite enough cash to get a new one either.

At regular zoom there are some mostly transparent fuzzy grey circles, and as I press the zoom button they get smaller, sharper, and darker.

What is this sensor of which people speak?

I guess I’ll try the air blaster first. If I do have to resort to finding a camera place, any idea of what ballpark of costs I’m looking at?

Most of the advice posted in this thread pertains to an DSLR type camera. The air blaster isn’t going to help you because you can’t remove your lens to access the sensor.

OK, that’s my camera, a simple P&S. There’s no way to clean the sensor, and unlikely that there’s any gunk on it anyway.

Just take a lens cleaning cloth that you can get from an eyeglasses store and wipe the lens clean. I do it all the time. Air blaster may help, but a simple wipe with a lens cleaning cloth is all you need.

4.6mm focal length when you zoom wide is going to result in a lot of depth of field. Really a lot. Could be that junk on the front of the lens could be resolved at wide angle and near focus.

The lens isn’t any more delicate than glasses and such - probably less, actually. Don’t clean it with sandpaper or anything, but a microfiber cloth and a modicum of care and you’ll be fine.