Camera Labs

Dust, we all hate them. I've got one which appears at the top left hand corner of my photos. So far, it's eluded me so I'm here to ask for help in tracking it down

1) It doesn't appear on shots taken with apertures less than f16. At f22, it's as clear as day.
2) Focal range doesn't matter. At f16 and above, it is clearly visible when you focus to infinity and it is also very clear when you focus as near as possible.
3) It isn't on the lense as it happens with all my lenses at the same spot.

I'm struggling to figure out where it could be . I hope it's not on the sensor or the low pass filter but if it is, why is it not visible/blurry at low f-numbers?

It's driving me insane.

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PhilipGoh.com

It's on the sensor. If it's not on the lens, were else could it be? Have you tried a blower on it already? If that doesn't shift it, then you'll have to get more serious. I ended up using sensor swaps and solution to shift a particularly troublesome spot on mine.

As for why they appear at small apertures, my best guess is here although I never got confirmation that is what's actually happening.

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Canon DSLRs: 7D, 5D2, 1D, 600D, 450D full spectrum, 300D IR mod
Lenses: EF 35/2, 50/1.8, 85/1.8, 135/2+SF, 28-80 V, 70-300L, 100-400L, TS-E 24/3.5L, MP-E 65, EF-S 15-85 IS
3rd party: Zeiss 2/50 makro, Samyang 8mm fisheye, Sigma 150 macro, 120-300 f/2.8 OS, Celestron 1325/13
Tinies: Sony HX9V.

It's not visible at low f-numbers because the DOF is small enough to exclude the dust speck. Sounds like it is definitely on your low pass filter, changing lenses doesn't help and it shows up in your shots so it's not on your focusing screen or mirror, I think a sensor cleaning is required.

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Graham
Flickr

I think I'll go buy a cleaning kit later today. It looks like scary business, but I've read through http://www.cleaningdigitalcameras.com/ and that seems to help a bit.

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PhilipGoh.com

Success! Got the blasted dust spec and I don't see any obvious ones now in the shots I take. Though I seem to have gained a small speck on the view finder.

Ah well, I'll live

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PhilipGoh.com

Glad to see you got it....


Did you use a wet cleaning kit or get it with the rocket blower??

If you got a cleaning kit, which one and did you learn anything

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Canon EOS 400D, EF-S 18-55mm, EF 24-105mm f/4L IS USM, EF 50mm f/1.8 MK I, EF-S 10-22mm, EF 70-200mm f/4L IS USM, EF 28mm f/1.8, EF 85mm f/1.8
Canon 430EX II, Manfrotto 055CXPRO3, Arca Swiss P0
Panasonic GF3, Panasonic 20mm f/1.7, Olympus 45mm f/1.8

MY FLICKR!

Congrats on the dust thing... and i think that if you can see it in your viewfinder then its on the mirror? dunno.

I bought this. http://www.lenspen.com/?cPath=&products ... 1&tpid=146

Initially started with the blower to remove any loose dust. But this bugger that was giving me grief was not willing to move, so I had to use the lens pen to gently wipe down the sensor. Took me a few tries to get the hang of it but I finally managed to get rid of it.

Now there is a small speck of dust that is visible on the view finder. I think it's on the glass that's directly above the mirror (which is spotless now) and it's hard to clean because the glass is "grooved". But I don't mind, as long as it doesn't visibly affect my finished photos

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PhilipGoh.com