digitial dust

Gary Glass · May 30, 2007

I'm having a devil of a time keeping my sensor clean (Canon 20D). I don't switch lenses very often, and I clean it carefully, but it still seems like I've always got a speck or two on the sensor. Am I missing something? Well, there's this:

http://the-rob-in-va.blogspot.com/2007/05/dust-in-wind.html

If anyone has any tips, I'd be happy to hear them.

ziggy53 · May 30, 2007

Gary,

When you say "a speck or two", are you talkng large specks or just pixel sized specks? Do you have any links to full sized images to demonstrate the problem?

rosselliot · May 30, 2007

well, see, I don't work in a camera store - - - - but it's going to attract dust no matter what! haha. When you take off the lens and expose the inner workings of the camera, you're destined to get dust in there. also, dust is so small, it really can slip into little crevaces and cracks that may be elsewhere in the camera. I just have the rocket blower and the visible dust sensor brush, and they work great.

it's inevitable.

- RE

cmason · May 30, 2007

For the second time in about a year, I've had to bring my digital SLR camera in to a camera
store to have the image sensor removed.

Whoa! Sensor "removed"? Are you sure about that? Never heard of that, and it sounds frightening. Dust is very common, and with care, very simple to remove. No need to 'remove' your sensor, or even take the camera to the store, do it yourself...I suspect you will do a much more thorough, if not careful job yourself.

A key thing to know, is that the sensor itself has a protective filter covering it, so when you clean the sensor, you are actually cleaning the filter on top.

Another area that caught me: dust also collects on the viewscreen, be sure to check, blow and clean that as well. (the viewscreen is at the 'top' of your camera...take off the lens, and then look 'up' through the opening. I cleaned and cleaned my sensor but could not eliminate dust spots that I could see (not in prints mind you). I finally realized they were not on the sensor.

The best info on cleaning your sensor, and in my personal use, the best 'system' around is known as the Copperhill method. It is not expensive, and works very well:

http://www.copperhillimages.com/index.php?pr=tutorials

pathfinder · May 31, 2007

After spending two weeks in the desert in Utah, I certainly did not limit my cameras to a clean room. I saw folk's cameras literally dragged through the sand last week.

It is important to think carefully about how to clean your camera after this kind of environment.

DO NOT USE CANNED AIR OR A ROCKET BLOWER. It will just blow dust/grit inside the camera bodies small openings.

I clean the outside carefully with a fine haired 1 inch paint brush, taking special care around the lens/body junction. Remove the eye shade around the viewfinder portal and brush to remove any grit from the viewfinder.

Some of the L lenses have a rubber seal around the base of the lens mount that tends to attract grit as well, so use the brush there until it is clean under a good inspection light. Then wipe the camera down with a microfibre cloth - I buy'em at Sam's in the auto department - these are not for lens cleaning, but to remove sand and grit from the external portions of the camera.

Now , and only now, are you ready to remove and swap a lens or "clean a sensor".

What we are actually doing when "cleaning a sensor" is cleaning the anti-aliasing filter in front of the sensor itself.

My first suggestions about sensor cleaning is to not do it at all, unless it is really needed. A few dust motes are best ignored, and cloned out of the image as necessary. If you are shooting landscapes at small apertures ( f16, f22 etc) you will want a clean sensor. If you shoot portraits at f2.8, a dirty sensor will never bother you in the least.

So - you've decided that your sensor needs cleaning, by shooting a frame of the sky at f16 and brought the image into Photoshop and increased the contrast of the image by Image>AutoContrast or whatever, and the dust motes stand out in the image. Note that these are NOT the dust motes that you see looking through the viewfinder - they are on the pentaprism screen and can be removed with a fine camel hair brush or a rocket blower, but are never seen in the image at all.

My first choice for sensor cleaning is a simple Rocket Bulb air blower - this will dislodge or move small hairs and dust motes and carries little to no risk to the sensor/anti-aliasing filter.

If dust motes are still present after using a Rocket Blower and checking a frame shot of the sky, I move to a Sensor Brush or an Artic Butterfly ( which is a sensor brush that does not require any canned air and can thus be transported on an airplane) - I carry a sensor brush in my camera bag when travelling as it is small and light and easy to use. Brush off the sensor and that may be all you need. Again the risk of the sensor brush/ Artic Butterfly is almost nonexistant.

Check the sensor again - this is getting tedious isn't it ( that is why I don't like to do it very often) Do you still have stuff struck to the sensor?

Now we go to Sensor Swabs and Eclipse, or the CopperHill method. We are now actually using a solvent and washing the windshield of the sensor so to speak. Use a minimum amount of Eclipse on the swab and carefully, but firmly, make one and only one pass across the filter in front of the sensor. The reason for the single pass is to avoid passing a particle of grit back across the "sensor" and scratching it. The risk of the CopperHill method is not large, but I do know of more than one case of a scratched anti-aliasing filter. That is why I do not get overly compulsive about a few dust motes on my sensors. Put the lens back on and fire another test frame of the sky looking for residual motes and swab again if necessary.

Congratulations, you should now have a clean camera and sensor and be ready to meet the world again.

I pack a micro-fibre cloth in my camera bag at all times to help remove grit from the external surfaces. I even use it without ANY pressure on the lens surfaces as well if needed. It is also a good thing to think about vacumning out your camera bag or clenaing it as well with a micro-fibre cloth. You do not want sand and grit from your camera passing to your bag and then back to a lens or camera body a second time.

rjpat · May 31, 2007

In my experience, the lens you use has a lot do with dust. When I first got my 20D I was using the kit lens and a cheap Tamron 70-300 and had a lot of trouble with dust. I had to clean the sensor every week or two (copperhill method). I now only use L glass and have very little trouble with dust.

Gary Glass · May 31, 2007

rjpat wrote:

In my experience, the lens you use has a lot do with dust. When I first got my 20D I was using the kit lens and a cheap Tamron 70-300 and had a lot of trouble with dust. I had to clean the sensor every week or two (copperhill method). I now only use L glass and have very little trouble with dust.

Yeah, that's about the same gear I have. I want the Canon L glass bad.

pathfinder · May 31, 2007

Unsealed zooms are notorious. Especially trombone stye zooms and that includes the 100-400 L of Canon.

I had a brand new 1DMkll and after an afternoon shooting airplanes with a 100-400 L my sensor was direly in need of cleaning. I never did any lens changing that day at all either.

I suspect high frame rate shooting is a bit more dirt prone also with all that hardware stirring up air currents in the mirror box.

com3 · May 31, 2007

heh... sensor dust. my goodness, have i had to deal with that. thankfully, i learned the trick...

i climb in the dirt, dust, mud, and crap all day long for my shoots. dirtbikes, supermoto, and road racing are what i make my living off of. hell, just a few days ago, i was getting tire particles blowing all over me, my camera, and my super sexy white shirt i had on coming offa T10 at infineon raceway. i get teh ebil dust frequently.

i know most of you are gonna cringe, cry, post disclaimers, and other stuff like that, but i've been doing this, about once a week, for about a year and a half now:

1 - set cam to "sensor clean" mode,

2- lightly blow on it, making sure i don't accidentally spit on the sensor (did that once before...made it uber clean, but took forever to get the swirls off...hehe)

3 - and stick a clean corner of my COTTON t-shirt in there and wipe the sensor off using my finger.

4 - blow again in case i knocked any dust off the barrel or whatever.

5 - eyeball it using direct sunlight (you can see the dust better under the sun)

it's usually pretty clean by then, but i always set shutter to 1/60 and take an unfocused panning shot across the blue sky at f/8 to check. that'll tell me right then and there if i got anything still on the sensor. every once in a while, i'll have to repeat the above steps a 2nd time. not often.

since i shoot motorcycles for a living, shooting at anything less than 1/320 will REALLY show dust spots. if my camera ain't 100000% clean, i ain't gonna shoot with it until it is.

dust spots are EBIL.

gus · May 31, 2007

Gary Glass wrote:

I'm having a devil of a time keeping my sensor clean (Canon 20D). I don't switch lenses very often, and I clean it carefully, but it still seems like I've always got a speck or two on the sensor. Am I missing something? Well, there's this:

http://the-rob-in-va.blogspot.com/2007/05/dust-in-wind.html

If anyone has any tips, I'd be happy to hear them.

I shoot with the dust & never see it. Are you doing landscapes with plenty of sky & a very small ap ?

I doubt there is a camera in here that gets more dust in it than mine. I swap lenses all day in this & at the most...i will lean over it as i do it to stop rocks falling in.

Desmond · June 1, 2007

I scratched the sensor on my D70 a while back in a moment of fraustration and a dry tissue . I have since learned a bit : zooms suck dust in and the most dust is indoors ! Something like 80% of dust in the house is human skin . When you want to change lenses indoors switch on a desktop lamp so you can see dust in the air . Open the windows [ especially if it has rained recently and the water has trapped all the dust in the air outside ] , when you no longer see dust under the lamp change lenses , keep the camera away from your body [ ever tried patting your shirt when there is a shaft of sunlight coming in through a window ? see the dust that comes off ? ] and pointed down .
For cleaning my sensor I haven't had to use more than a sensor brush since moving away from the coast [ no more stuck to the sensor ] . Get one of those foot bellows pumps and glue a dust mask filter on the inlet , pump air over the brush and it gets static , wipe the sensor once , pump again to blow off the dust and wipe the other half . I have had good success that way after a lot of messing with the copperhill method and the right amount of fluid etc.
Remember to let the dust blow out of the house first with the windows open , save it for a rainy day when there is no dust in the air if possible .
I look forward to the day when Nikon cameras have olympus dust reduction !

thebigsky · June 1, 2007

I hate sensor dust with a passion, I've taken to employing the 'Indiana Jones' method of lens changing, I put the camera on its back and unscrew the lens on my camera but leave it in place, I then take my new lens in my right hand and hover it by the camera, whip out the unsrewed lens and insert the new one in one action.

It doesn't seem to make much difference though

Charlie

claudermilk · June 1, 2007

I typically shoot in more benign environments than some of you (I understand the amazing amount of stuff thrown up by passing racers). So, I don't jump through all sorts of hoops when changing lenses. However, I have changed in all sorts of places--beaches, up a tree in the jungle, cramped dusty light booths in theaters, etc. I just have the next lens ready-mount up with the rear cap loose. Make sure the body is pointed down while open & just do the swap quickly--but not rushed. My 20D is about 3 1/2 years old and I rarely have to clean the sensor (ok, so I manily shoot wide open too); I've swabbed twice & used a Copperhill sensor brush about a dozen times.

This is one of the biggest mountain-of-a-molehill topics I see on photography fora. It's really not as big of an issues as people make it out to be, and it's not nearly as hard or dangerous as the Chicken Littles would have you believe. Just take some time & care while doing the cleaning.

Desmond · June 1, 2007

claudermilk wrote:

This is one of the biggest mountain-of-a-molehill topics I see on photography fora. It's really not as big of an issues as people make it out to be, and it's not nearly as hard or dangerous as the Chicken Littles would have you believe. Just take some time & care while doing the cleaning.

My first lens change with my first dslr was in a car which had just driven along a dusty road and I was 1000km from home , I never knew about dust getting on the sensor then . I saw these two spots in the sky in all my picturesand went into a shop and asked how to clean it . They told me to use a blower so I did , with the brush still on and it got 10X worse . I went onto the net and found out about the copperhil method and used a cheap spatula and lens tissue and too much solvent . About 8 attempts and a lot of sweating later it was clean . A few months later I managed to scratch the sensor by pushing too hard on a stubborn piece of dust which cost me a new sensor , so I wouldn't under-state the problem involved .
Once when I thought the sensor was clean since I had only left the 18-200 lens on since the last clean I did a F32 shot to slow down a fountain and saw hundreds of little spots in the picture which meant another clean .
A molehill on a sensor is effectively a mountain !

claudermilk · June 3, 2007

I'm not going to argue about it. My point is that in general, in my opinion, this is one of several subject that have gotten blown out of proportion to the actual issue. Apparently our opinions don't mesh...oh well, I'm not going to lose sleep over it & I suggest you don't either.

Joemess · June 3, 2007

claudermilk wrote:

I'm not going to argue about it. My point is that in general, in my opinion, this is one of several subject that have gotten blown out of proportion to the actual issue. Apparently our opinions don't mesh...oh well, I'm not going to lose sleep over it & I suggest you don't either.

Gotta agree with you on that one.

Give it a quick puff and move on. I have my camera in all types of woodland / outdoor / windy conditions and I have never gotten any speck on the sensor that a little puff of air would not remove. This is one of those pseudo crises that sell lots of little gizmos and gives folks something to talk about.

My 2 cents.

michaeln · June 3, 2007

If you do decide to clean your sensor, I hope you are much better at it than I am:

http://michaelnel.smugmug.com/gallery/2808360#149987694

Desmond · June 3, 2007

michaeln wrote:

If you do decide to clean your sensor, I hope you are much better at it than I am:

http://michaelnel.smugmug.com/gallery/2808360#149987694

I know where you are coming from , I think it had something to do with living near the beach but the dust spots I got there stuck sometimes .
Once I bought a second hand D70 and it arrived with a large spot stuck to the sensor . I used "sensor swabs" which do a decent enough job but it was stuck so hard it tore pices off the tissue until I left a drop of cleaning fluid on the sensor for a while and then it came off in pieces after 3 more wipes ... Most of the time people are lucky enough to just have dust settled on the sensor that blows off easily , but when conditions are damp and things get bad try telling a customer the spot on all their pictures is no big deal !

ire-david · June 12, 2007

digital dust
having read the horror stories about scratched sensors i am so glad that i bought my digital slr where i did.

ok it cost about 200 euro more than the mass retailer down the road, but they perform the sensor cleaning for free. definatly worth the extra money for that sort of piece of mind.

Desmond · June 12, 2007

ire-david wrote:

having read the horror stories about scratched sensors i am so glad that i bought my digital slr where i did.

ok it cost about 200 euro more than the mass retailer down the road, but they perform the sensor cleaning for free. definatly worth the extra money for that sort of piece of mind.

That's a good deal . Over here it costs NZ$180 to have it cleaned by Nikon .

Strav · June 12, 2007

Noticed dust on my Canon last evening shooting a sunset with a long lens closed down. Was depressed there for a bit, but found a local guy about a block away from me that services all of Henry's cameras (largest cam. store in Toronto). Charged me $70 Canadian for a 2 day turnaround. I'm happy. Figured I wasn't going to tackle this myself because I'd be at it for hours based on how long it takes me to wash a car, or clean my home or office.

Desmond · June 13, 2007

Strav wrote:

Noticed dust on my Canon last evening shooting a sunset with a long lens closed down. Was depressed there for a bit, but found a local guy about a block away from me that services all of Henry's cameras (largest cam. store in Toronto). Charged me $70 Canadian for a 2 day turnaround. I'm happy. Figured I wasn't going to tackle this myself because I'd be at it for hours based on how long it takes me to wash a car, or clean my home or office.

A very wise decision . I would happily pay that amount for someone elses to do it properly . I would advise doing a proper dust reference photo as soon as you get it back .

digitial dust

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