Sensor Cleaning

[MarkBarbieri]

The scourge of the DSLR.

1) How often (if at all) do you clean your DSLR sensor?
2) How do check to see if it is dirty?
3) How do you clean it?
4) Has getting a DSLR with the anti-dust shivering helped?


I'll start with my answers.
1) Only when necessary. It may be once a day. It may be once in a few months. I do it when I notice that it is dirty.

2) Sometimes I notice in shots that I've taken and that prompts me. Other times I check before I got on a big shoot. I check by setting the aperture to the smallest setting (highest f-stop) and either shooting through my Expodisc (it's like an extreme diffusion filter) or by shooting something with no detail (clear sky or solid cloud, a non-textured wall, or a campaign speech). Depending on my mood, I either look at the image on my computer or I look at it on the LCD on the DSLR. If I use the LCD, I magnify it as much as possible than then scroll across the entire image in stripes. I'm just looking to see if there is more dust than I find acceptable. It's just about never pristine.

3) I clean with a little battery powered blower. Following that, I either use a sensor cleaning brush or a Dust-Aid (a little sticky thing like a post-it note on a stick). If that still doesn't cut it, I use a pec-pad on a stick and wipe it.

4) My sensor only shakes when I'm hand-holding the camera, so I have no answer for this one.


The affect of aperture on sensor dust is interesting. When I first started shooting with DSLRs, this baffled me. Here's my attempt at explaining it. This should show why you want to use a small aperture when checking for dust and why dust is a bigger problem when using small apertures.

The aperture is the opening in the lens. A wide aperture (low f-stop number) is a big hole and a narrow aperture (high f-stop number) is a small hole.

A piece of dust isn't actually on the bit that does the sensing. On top of the sensing bits are other things like microprisms, anti-aliasing filters, and maybe evening a little protective coating. So the dust is sitting just a bit in front of the actual sensing parts.

When you are taking a picture with a wider aperture, light is hitting the sensor bits from a lot of different angles. A piece of dust might block some of the light, but other bits of light will get past it because they are coming in from other angles. When you are taking a picture with a narrow aperture, the light is coming through a much smaller hole. If there is a piece of dust in front of the sensor, it's going to block more of the light from the sensor parts behind it. In photography terms, the wider the aperture, the softer the shadow behind the dust spec.

So when you shoot wide open, the dust specs are softer and less noticeable. When you shoot with a small aperture, the dust specs are harder and stand out more. That's why you check for dust with a narrow aperture; you can see it better that way. It's also why dust is a bigger problem when you are shooting with a narrow aperture.

One other trick you can use when you don't have a solid colored surface for your dust check is to take a very out-of-focus shot using a very small aperture. The aperture size is what determines how hard the edges are for the dust spot. If everything else is extremely out-of-focus and soft looking, the hard edged dust will stand out more. At least that's the theory. I've never actually tried that but I've been told by others that it works for them.

 

[MarkBarbieri]

Oh, and I should add that when I check for dust, I'm just seeing if it is there or not. I don't look for it and then try to clean that spot on the sensor. I get too confused about which part of the sensor maps to which part of the image.

 

[DVC Jen]

1. Only when I have to... when I start noticing things. I will probably do it again before we leave for Disney in June. I will be using a smaller aperture more then than I do normally.

2. Not as often as I should - probably every few months - I kinda feel like if it isn't noticable in my photos - ignorance is bliss. If I knew it was there it would make me nuts.

3. blow it first with a bulb type thingie (more tech talk from me ) and then I use a wet swab - pec pads.

4. The XTi does - but I think it is useless.

 

[mabas9395]

I used to try to clean it with a Rocket Blower about weekly depending on use. Then one day I got a single stubborn spot and really blew the heck out of it with the rocket blower and noticed that it had multiplied 100 times and my sensor was now completely covered with specks. I must have blown so hard that I dislodged some dust from the sensor area.

When it happened I got so freaked out that I bought the Copper Hill Cleaning kit to take care of it. But I'm also parnoid about ruining my sensor so I haven't even used the C.H. kit yet.

They are only visible when I shoot beyond f/16 or so, which I never do unless I am checking for dust so it hasn't been a problem yet. But now that the weather is nicer I hope to get out and shoot some landscapes which I usually do closer to f/8 or f/11 or so. So it may be time to get brave and finally do a good wet cleaning.

Worst thing that can happen is that I get a clean sensor out of it. Best thing that can happen is that I get a scratched XT and a brand new 40d.

 

[Gdad]

I just got the first spec of dust (visible with my regular shooting style) on my D300 a few days ago. I just passed the 10,000th shutter actuation mark- so not too bad I guess. I don't know if the automatic sensor cleaning does anything or not- maybe it has kept it clean this far- but it is not dislodging this clump. Hopefully a rocket blower will- I have never tried a wet cleaning. I think the local camera repair shop charges like $50 for it- I will probably just go there. (That is who de-gunked my D70 when I foolishly sprayed compressed air from a can at the sensor- not a good thing to do. )

 

[Code]

1) How often (if at all) do you clean your DSLR sensor?
2) How do check to see if it is dirty?
3) How do you clean it?
4) Has getting a DSLR with the anti-dust shivering helped?

This is one area where Olympus owners are fortunate. I'm hardly careful changing lenses unless there is spray or sand around.

1) Never
2) f/22 blue sky or wall, extreme contrast boost in photoshop if I'm being really thorough
3) I haven't yet
4) Obviously yes

I'm going to have to get a Rocket Blower anyway.. I'm having a dust problem on the viewfinder screen.

 

[handicap18]

I use a rocket blower when I see bunnies show up on my images (maybe once a month depending on how often I'm shooting and changing lenses). Thus far, that has worked very well. When things get bad I do a wet cleaning (once or twice a year). I'll check for dust every now and then by shooting at a blue sky at f/22. I don't have an answer for #4.

 

[AndrewWG]

1. I clean it about once every 2 months or so when I think about it or notice my photos having spots.

2. Same as most people I suppose. Smallest aperture (f22 or above) taking a pic of the blue sky. I have used a white wall too, but never a campaign speech as they are full of gobbledy gook.

3. I only use wet cleaning using the Photographic solutions (Copper Hill) method. I did try the rocket blower and found that I was blowing more dust around then actually cleaning it. My DD walked off with that thing months ago and I haven't seen it since.

4. I don't have auto sensor cleaning but know of someone who does and is not very careful with the camera and is in a VERY dusty environment to take pics, and the sensor is still quite clean. I think they work, but who knows, maybe they have just been lucky.

 

[Groucho]

Well, there's two answers to #1, which skews the rest. There's two cleanings I do - Rocket Blower, and the full wet wipe of the sensor itself.

On my *ist DL, I had to do my first big cleaning of the sensor after my WDW trip. Before that, I was a bit cavalier about lens changing. I've since gotten much more circumspect. I did clean the sensor a couple more times since then, but most of the time, the Rocket Blower did the trick.

On my K100D, I've only ever had to use the Rocket Blower, it's somewhere north of 4,000 photos so far.

On my K20D, I haven't had to do anything. It has several features designed to minimize dust. It has a special coating on the sensor, a fairly vigorous shake (on demand and/or on startup), and adhesive under the sensor to catch the dust. It can also automatically check for dust and show you a picture on the LCD of how the sensor looks and where noise is (even reversed, so it looks the same as it will when you pull the lens off - you even see the outside of the lens mount ) and it also makes a "dust" folder on the memory card and puts "dust.jpg" in there so you can pixel-peep it if desired; no more taking photos of white paper and doing "auto levels" in Photoshop.

It will get a real workout this upcoming trip, and I have the Rocket Blower with me - hopefully it'll stay dust-free though but I will be changing lenses a lot.

 

[fitzperry]

This is one area where Olympus owners are fortunate. I'm hardly careful changing lenses unless there is spray or sand around.

Why are Olympus owners better off in this regard?

On my K20D, I haven't had to do anything. It has several features designed to minimize dust. It has a special coating on the sensor, a fairly vigorous shake (on demand and/or on startup), and adhesive under the sensor to catch the dust.

Hope this isn't too far off-topic, but for those of you who have a camera with a shake thingy type dust reduction system (see, I'm proficient with the technical lingo too ), do you have it set to do that on startup or do you just use it periodically? I have mine set to "clean" on startup.

Oh, and to answer the original questions so as hopefully not to offend Mark with my off-topic questions:

1. Only when absolutely necessary, which fortunately has not been very frequently, as it still scares the heck out of me.
2. Same as everyone else--small aperture, blue sky. Tried the white wall, auto levels deal once too.
3. Rocket blower first (that doesn't cause me too much anxiety); Copper Hill cleaning system if that fails.
4. Jury is still out on that one. I have not had to do a wet cleaning on my D300 (knock on wood), but I haven't had it for very long so I can't really say whether it helps or not.

 

[boBQuincy]

Not much new to add here, I usually clean the sensor before a trip or photo outing.

Any featureless surface will do for a dust check. The usually is some to be found after any trip. Political speeches don't work, they shift around too frequently to find anything at all.

I use the Copperhill method, it is the most reliable I have found.

None of my cameras have shake thingies, the only report I read was not too impressed with them so they are not a big selling point to me.

boB

 

[Code]

Why are Olympus owners better off in this regard?

Because Olympus' anti-dust system is very effective, the industry leader for sure. I doubt that it's 100% but I haven't had a single dust spot yet.

 

[cpbjgc]

I was reluctant to answer so as not to "jinx" my streak

1) Never;
2) I am a horrible pixel peeper, always watching for dust;
3) No method as yet (keep meaning to pick up a cleaning kit, but never have)
4) Yes - I think it works, since I have never had problems with dust to date, and I do change my lens with some frequency (but not at the beach

I think the Canon dust removal/control system got a bad rap because of the "test" done on a photography site where the basically emptied dust on the sensor to see how it worked - not exactly a realisitic test, unless you normally change lenses while emptying your vacuum cleaner or operating a cricular saw. The system is meant to control dust that's normally around and was not a sensor cleaning system.

 

[MarkBarbieri]

Because Olympus' anti-dust system is very effective, the industry leader for sure. I doubt that it's 100% but I haven't had a single dust spot yet.

How is the Olympus system different? What makes it the industry leader? I've not heard anything about it.

Intuitively, I would think sensors with higher pixel densities would have more dust concerns. Any given piece of dust would block more pixels and would be magnified more on a higher pixel density sensor than on a lower pixel density sensor. My intuition may be totally wrong.

It has a special coating on the sensor, a fairly vigorous shake (on demand and/or on startup), and adhesive under the sensor to catch the dust.

Coatings sound like a partial solution to me. Anything that reduces the chances that dust will stick are good.

I'd love to see reworld tests on how effective shaking is. At the dust particle level, I would think that eletrical attractions would dwarf the other forces at work. I'm not sure that shaking would do much.

The adhesive idea sounds great, but only if it is replacable. I can foresee a day when the air in the chamber is circulated through a little replaceable dust sensor that is charged to pull as much dust out as possible.

I'd like to see some type of windshield wiper like arrangement that can "dust off" the sensor on demand. That might have problems with smearing, though.

I've noticed a lot of variability in how much a problem people have with dust. I suspect that there are a lot of factors being the camera's dust handling capabilities. There are differences in how people shoot. Sports shooters tend to use wider apertures than portrait shooters, so they are probably more tolerant of dust spots. Some people change lenses frequently and others don't. There are probably differences in lens changing techniques. I assume that dust climate is also an issue - some places are just dustier than others.

I used to read about people steaming up their bathroom for a while before cleaning their sensor. They figured that the moisture in the air would capture the dust. I don't read about people doing that anymore.


It's probably worth reminding people to make sure that they clean their sensor only with a reliable source of power for the camera. Either plug it into the wall or use well charged, reliable batteries. If you lose power while cleaning, your shutter may close on your cleaning tools. Shutters are very fragile and somewhat costly to replace.

 

[boBQuincy]

... At the dust particle level, I would think that eletrical attractions would dwarf the other forces at work. I'm not sure that shaking would do much. ...

At the voltage our sensors use the electrical attraction is not much. This is nothing like the static from a CRT (with thousands of volts). Also the attraction decreases rapidly with distance, even the small distance from the sensor through the anti-alias filter.

... It's probably worth reminding people to make sure that they clean their sensor only with a reliable source of power for the camera. Either plug it into the wall or use well charged, reliable batteries. If you lose power while cleaning, your shutter may close on your cleaning tools. Shutters are very fragile and somewhat costly to replace.

This is a good idea but in the rare event of a power blip at home the shutter would probably get farkled if we use 110V power. Maybe using our PC UPS would help? It's cheap insurance to avoid a $200+ farkle fee!