Is this sensor dust or debries?

toadlet

I have had this "issue" now for several months now and am wondering if the problem is acutally sensor dust or something to do with lenses.

When I head out and shoot a CF card full of shots a few of them now and again will come back with dark marks in the lighter areas of the photos. I would say by guessing this happens in around 1 in 20 images.

From all the research I have done on the forums and the internet it seems that sensor dust doesn't move and looks more like an out of focus blob, not hard black small dots. I have also heard that its impossible for dust/dirt in a lens to show up in photos as it would be out of focus. I have looked in all my lenses and no dust that I can see.

These examples can happen on any apature and with any lens. The annoying thing is that it happens so randomly in that it can happen in one image and then not for dozens and dozens of shots later.

Here are some 100 per cent crop samples.

Harryb

Looks Like dust to me. To be sure take a picture at a small aperture (f/16 for example) of a white wall or a blue sky.

toadlet

Harryb wrote:

Looks Like dust to me. To be sure take a picture at a small aperture (f/16 for example) of a white wall or a blue sky.

Do you think its dust on the sensor or dust showing up that might be inside lens/s?

The porblem with doing the white wall/blue sky test is that like I said the marks are so random. Can shoot loads of shots of sky and nothing, and then all of a sudden these specs can appear

Harryb

Sensor dust

toadlet

I feel like I am the only one with this "problem" as I have done many image searches and have never see dust like this in other peoples photos before.

Still, if it is indeed dust, I was thinking of getting the Arctic Butterfly Dry brush. Don't want to play around with wet swabs atm. I have also triend a bulb blower. Has anyone used the Butterfly brush, is if safe?

Harryb wrote:

Sensor dust

Richard

Harryb wrote:

Sensor dust

As mentioned above, take a shot of a uniform sky at f/22. Drop it into Photoshop and run auto-levels. Prepare to be horrified.

toadlet

Richard wrote:

As mentioned above, take a shot of a uniform sky at f/22. Drop it into Photoshop and run auto-levels. Prepare to be horrified.

Thanks Richard. I have done this test at f22 and yes I do have the usual dust bunnnies over the image when applying levels.

The images above are differnet to normal looking sensor dust wouldn't you agree? Have you ever seen anything like these as sensor dust before?

Harryb

toadlet wrote:

Thanks Richard. I have done this test at f22 and yes I do have the usual dust bunnnies over the image when applying levels.

The images above are differnet to normal looking sensor dust wouldn't you agree? Have you ever seen anything like these as sensor dust before?

Many, many times :cry

I use the Artic Butterfly, its overpriced but very effective. Most dust can be removed with a good blow from a Rocket Blower.

Richard

toadlet wrote:

Thanks Richard. I have done this test at f22 and yes I do have the usual dust bunnnies over the image when applying levels.

The images above are differnet to normal looking sensor dust wouldn't you agree? Have you ever seen anything like these as sensor dust before?

Looks like normal dust to me. I suppose it could be some other kind of debris, but I would bet that whatever it is, it's on the sensor, not in a lens.

toadlet

OK, thanks for the replies so far guys. I think just seeing confirmation of other peoples dust that looks like my photos would be good, because as I have said I havnen't seen them anywhere else on the net like mine. If you have samples or links please do send them.

Regarding the Arctic Butterfly brush. I was looking at the SL700 model to clean a 1.6x sensor. Will this do the trick? What would cause it to show like dark blobs on the sensor rather than the more common fuzzy out of focus blobs? My thinking is it could be metal shavings from the lens itself?

Richard wrote:

Looks like normal dust to me. I suppose it could be some other kind of debris, but I would bet that whatever it is, it's on the sensor, not in a lens.

ziggy53

toadlet wrote:

... My thinking is it could be metal shavings from the lens itself?

Let's hope not!

Yours certainly looks familiar to me and I believe it is common dust. (Been there, done that.)

It's always a good idea to blow off the sensor prior to actually touching it with anything, Once you do start physical cleaning, use a light touch to start with and change surfaces, or blow off the sensor brush, frequently to get rid of anything potentially abrasive. Test the camera with the f22/Levels test to gauge your progress.

You may be surprised to see how tenacious some of the crud is with dry cleaning alone, so do prepare yourself for the possibility of wet cleaning as well.

Don't over clean. The f22/Levels test becomes more sensitive as you eliminate the problem. Perform a more sensible manual Levels test at maybe twice the amount you would ever consider using in an actual photo. When you can't see the problem at that stage, you will not see it in practical application either.

Google Images for sensor dust examples:

http://images.google.com/images?hl=en&q=sensor+dust&btnG=Search+Images&gbv=2

ipduffy

Cleaning how-to with examples
Hi:

I found an article about sensor cleaning that was very helpful the first time I needed to clean my sensor. It's at www.the-digital-picture.com which is mostly for Canon stuff, but the cleaning tips are universal I think. There are a lot of sample pictures and how-to information.

Here is the link. Cheers!

jwear

yes --clean the sensor or have someone do it

Freezframe

Just did mine about a week ago !!!!!
My Dust look very similar, maybe a little more transparent ,but dust is made up from a lot of different entities....Human skin ,dirt,lint,etc.....I to used Arctic Butterfly SL700 to be exact...Work quite well indeed.

Make sure you use ac adapter or your batteries are at full...It's a little nerve racking the first time ..... U CAN DO IT !!!!

Goodluck : Brady

toadlet

Freezframe wrote:

My Dust look very similar, maybe a little more transparent ,but dust is made up from a lot of different entities....Human skin ,dirt,lint,etc.....I to used Arctic Butterfly SL700 to be exact...Work quite well indeed.

Make sure you use ac adapter or your batteries are at full...It's a little nerve racking the first time ..... U CAN DO IT !!!!

Goodluck : Brady

OK, sounds like then it might be dust, even though I haven't seen anyone elses dust look like mine:) I will have to give a contact method of cleaning a go. Would people who use the Arctic Butterfly recommed I go the SL700 or the SL747? Should I also buy a rocket blower and use this first? How much or a risk is there in scratching the internal filter?

cmason

toadlet wrote:

OK, sounds like then it might be dust, even though I haven't seen anyone elses dust look like mine:) I will have to give a contact method of cleaning a go. Would people who use the Arctic Butterfly recommed I go the SL700 or the SL747? Should I also buy a rocket blower and use this first? How much or a risk is there in scratching the internal filter?

try Copperhill method, works like a charm, and much cheaper than Artic butterfly. get the wet+dry kit, comes with a brush for a quick wipe, you charge it with a can of air, rather than the artic butterfly spinny thing.

toadlet

cmason wrote:

try Copperhill method, works like a charm, and much cheaper than Artic butterfly. get the wet+dry kit, comes with a brush for a quick wipe, you charge it with a can of air, rather than the artic butterfly spinny thing.

Thanks for your comments. I would prefer to try the dry butterfly method first, as seems less invasive than the wet method.

cmason

toadlet wrote:

Thanks for your comments. I would prefer to try the dry butterfly method first, as seems less invasive than the wet method.

Fair enough. I bought this from Copperhill, it is a dry brush, works great, costs only $22. Artic butterly basically is similar, but 'spins' to apply a static charge to the brush.

BTW, the wet method is no more 'invasive' and not nearly as frightening as it seems. It works the best, as often there are spots or dust I can not get rid of otherwise.

Robinivich

I've yet to get around to this, but it pays to remember that you're not brushing the sensor itself. It's the low pass or high pass or whatever filter in front of the sensor itself. There are actually several layers of filters to "prepare" the light for the sensor to process; UV and IR so the spectral range is close to what the human eye sees, anti aliasing so prevent colour moire, not sure if there are any others I'm missing. Obviously still a very important little piece of glass, which you do not want to damage, but it's not like you're brushing the microlenses or something.

So you're wiping down a piece of glass, not the business end of a potentially several hundred dollar microchip.

My plan for sensor cleaning... get a 40d, then practice on my now quite dusty XT...

ziggy53

The one thing I would be careful of is that some of the newer sensors have an anti-static film applied to the antialias filter or cover plate. While the filter or cover plate is difficult to scratch, the anti-static film can be affected by either too much physical abrasion or the wrong cleaning fluid.

toadlet

ziggy53 wrote:

The one thing I would be careful of is that some of the newer sensors have an anti-static film applied to the antialias filter or cover plate. While the filter or cover plate is difficult to scratch, the anti-static film can be affected by either too much physical abrasion or the wrong cleaning fluid.

OK, cool I will give one of the cleaning methods a go and see how things work out. Would still like to see anyone else with spots like I have though Thanks for everyones comments and help thus far.:D

claudermilk

I don't have any examples--I don't tend to save dust bunny images, but I have seen that kind of sensor dust before. IIRC it's usually the nasty, sticky crud that does that, so I expect a wet method cleaning is in your future. I'll also recommend the Copper Hill kit. I got the package with both the set cleaning supplies & the brush, still less than half that VD gizmo. I refuse to recommend anyone waste their money with those crooks.

toadlet

claudermilk wrote:

I don't have any examples--I don't tend to save dust bunny images, but I have seen that kind of sensor dust before. IIRC it's usually the nasty, sticky crud that does that, so I expect a wet method cleaning is in your future. I'll also recommend the Copper Hill kit. I got the package with both the set cleaning supplies & the brush, still less than half that VD gizmo. I refuse to recommend anyone waste their money with those crooks.

OK so if it's nasty, sticky crud as you claim then why does it not show up in every image? As I have said in earlier posts I can shoot the blue sky 20 times at f32 and not see these dark specs, and then all of a sudden they are in some - so obviously they must be moving around.

ziggy53

toadlet wrote:

OK so if it's nasty, sticky crud as you claim then why does it not show up in every image? As I have said in earlier posts I can shoot the blue sky 20 times at f32 and not see these dark specs, and then all of a sudden they are in some - so obviously they must be moving around.

I think CLaudermilk was relating from his experience, not saying for sure what "you" have. I don't recall you mentioning the "moving around" before?

toadlet

ziggy53 wrote:

I think CLaudermilk was relating from his experience, not saying for sure what "you" have. I don't recall you mentioning the "moving around" before?

Thanks yeah, was talking about when I said

"...The annoying thing is that it [specs] happen so randomly in that it can happen in one image and then not for dozens and dozens of shots later."

Sorry not as clear as "moving around", but yeah, it gets me thinking that they are moving around as they are not in the same place on every image.

claudermilk

toadlet wrote:

Thanks yeah, was talking about when I said

"...The annoying thing is that it [specs] happen so randomly in that it can happen in one image and then not for dozens and dozens of shots later."

Sorry not as clear as "moving around", but yeah, it gets me thinking that they are moving around as they are not in the same place on every image.

Yep, like ziggy said. I missed the moving around part. Hmmm... Dunno about that. I'd still give it a thorough cleaning & see where it is after that.

evoryware

Been there done that till Canon put in the self cleaning system

toadlet

Thanks for the images. I assume the last 2 are with your new camera? The black line on on the bottom of your first photo looks closer to what I have been getting.

evoryware wrote:

Been there done that till Canon put in the self cleaning system

toadlet

Upon researching the differnet cleaning options I cam accross this video on youtube. I don't know what others think, but I found it rather interesting that he was blowing around in the sides of the chamber first; I thought this would just make more of a mess. Suppose everyone has a differnet approach

http://www.youtube.com/watch?v=kxym2dhFPPA

evoryware

the black line in the bottom of the first picture is an airplane. The dust surrounding the plane and in the top and bottom left corner is what I'm talking about. That was shot at f/16. That dust can also be seen in the 2nd and 3rd pictures but it is blurrier because I was at f/11. I have circled them for you. I asked the same question on forums as you and immediately purchased and used the Giottos Rocket Blower only on the sensor. The dust disappeared. TIll some more replaced it. Blew it out again.
Eventually got the XTi. No more blowing. My new cameras have not had any dust problems at all.