Marks on pictures

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snappit

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Ken
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Hi all. First of all hoping I have posted in the right section but am asking for some help please.

For various reasons it's been a long time since I've posted on here or been doing photography. I'm at the point to start up again and got my camera (canon 40D) out again. I thought I would clean the sensor but when doing some test shots at f22 I noticed some strange marks in the top right hand corner. This doesn't show up at larger apetures such as f8 and was wondering what it could be. I've cleaned the sensor and got rid of most of the dust spots that you can see but these lines still remain. The nature of the marks doesn't suggest to me a scratched sensor and I don't know how I would have scratched it anyway. It looks to me like hair or something. Does anyone have any ideas what it could be or how to rectify it. Many Thanks.IMG_6745.JPG
 
just clean it again and remember the marks are upside down, if I remember correctly

take a shot of a white wall at f/16 or above, it does not have to be in focus to shown the marks
 
It looks like fibres of some kind. Get in there with a blower brush and do the edges of the sensor thoroughly. I imagine there's a small chance it could be fungus, though I've not heard of that on sensors before.
 
Looks like moisture of some kind, possibly oil.

Get the right cleaning fluid and give it another go or maybe two.
One of the loupe lights helps see any contamination in greater detail
 
It could be dried cleaning fluid if you used too much or it was old and did not evaporate properly.
 
Is your cleaning kit of reputable make? Did you air-blast the mirror-box with the mirror up & the camera held upside down before starting? Did you use a fresh swab of the right dimension for the sensor from a just-opened packet? Did you apply the stipulated amount of correct fluid? Did you wipe the sensor across & then back, or what?

And I don't think it's mould, but mould can occur on almost any substrate ... unless the substrate's transparent or reflective, we rarely see it.
 
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Hi all. Thanks for your replies. I use Dust Aid cleaning swabs and liquid so a reputable brand. Did all the cleaning correctly but don't think that can be the issue as the marks were there before I cleaned it. Have now had a good look at the sensor and it does appear that for some reason there are marks on the sensor itself. No idea how they got there, a real mystery as this is the first time I've cleaned the sensor. Went out with the camera today to do some macro shots with my new Sigma 105mm Macro lens (great lens by the way) and the marks aren't showing. I do need a new camera anyway as this one is fairly old and I need to update.
 
Some sensors are coated, so there is the possible chance that what you're seeing is cracking of the coating or possible fungus underneath it.

Anyway, although I've always cleaned my own sensors; I'm no expert on these matters so I'd suggest taking it to someone who is.
 
snappit said:
Hi all. Thanks for your replies. I use Dust Aid cleaning swabs and liquid so a reputable brand. Did all the cleaning correctly but don't think that can be the issue as the marks were there before I cleaned it. Have now had a good look at the sensor and it does appear that for some reason there are marks on the sensor itself. No idea how they got there, a real mystery as this is the first time I've cleaned the sensor. Went out with the camera today to do some macro shots with my new Sigma 105mm Macro lens (great lens by the way) and the marks aren't showing. I do need a new camera anyway as this one is fairly old and I need to update.
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I recall having a dust/mark issue on a camera that had been converted to IR. This involved replacing the hot filter with an IR pass filter and can result in debris on the sensor. The hot filter is the bit that you clean, the sensor is beneath the filter glass. One thing that stuck with me is that the dust/marks will be much more focused if the debris is actually on the sensor itself. If, like your experience, the marks disappear at larger apertures and are quite diffused at their sharpest, then it's likely that they are (difficult to shift) marks on the outside... unless there is a larger than normal gap between the sensor and filter.
 
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