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wideangle
02-11-2008, 2:48pm
I have been looking at some of my photos that show stuff that has landed on the sensor
and contrary to what material I have read about sensor dust on the internet; a) sensor dust
doesn't just appear as 'dust bunnies' (soft out of focus specs) and b) it can move around
from shot to shot.

The photos below have been taken at f8 and with different lenses, and shots
and in each shot the specs appear in differnet areas. Then in many other
shots of sky detail etc there is nothing, wheather shooting at a high or low f stop. So
it seems that sensor dust can move around and can appear as hard defined specs,
not just soft out of focus ones and always in the same spot as posts and articles about
the issue suggest. Unless of course a UFO has landed in this neck of the woods! lol

Here are some samples:
http://thomasryan.smugmug.com/photos/407701380_cW4bj-L.jp

http://thomasryan.smugmug.com/photos/407701371_WUptg-L.jp

http://thomasryan.smugmug.com/photos/407701366_YcE5G-L.jp

Kym
02-11-2008, 3:04pm
Handy links...
* Changing Lens (dust) http://www.clarkvision.com/photoinfo/dslr.changing.lenses/
* Cleaning Digital Cameras - The Methods http://www.cleaningdigitalcameras.com/methods.html
* Dust http://www.cameralabs.com/workshops/dslr_dust/page3.shtml

Blower 1st... try a magnifying glass and see if you see anything on the sensor.

Seesee
02-11-2008, 3:56pm
Must say I've not seen sensor dust in a long shape before as are these....maybe not dust but a smear from something, hopefully not scratches.

Some sensor duust moves for sure, but depends on well it adheres to the sensor no doubt.
Generally sensor specs will show up more on images taken of bright subjects and more so at smaller aperatures of f8, f16 or above.

wideangle
02-11-2008, 4:59pm
Must say I've not seen sensor dust in a long shape before as are these....maybe not dust but a smear from something, hopefully not scratches.


I don't reckon it would be scratches on the sensor anyhow as these spots show up in different places in all shots. Would think that if it were scratches then it would be in the same spot.

davesmith
03-11-2008, 3:54pm
I'm not surprised dust moves around. Unless it's physically stuck to the sensor it would have to succumb to the same forces that got it there in the first place, whether it be gravity, suction, static or whatever. It'll still move around.

My sensor moves around as well every time I take a shot, not to mention vibrating every time I turn it on/off, so that adds to it too. Longer specs tend to be hairs. Generally a blower will get rid of it all (or at least blow it into a nook and/or cranny where it might stay out of the way for a while).

Kym
03-11-2008, 3:59pm
I'm not surprised dust moves around. Unless it's physically stuck to the sensor it would have to succumb to the same forces that got it there in the first place, whether it be gravity, suction, static or whatever. It'll still move around.
My sensor moves around as well every time I take a shot, not to mention vibrating every time I turn it on/off, so that adds to it too. Longer specs tend to be hairs. Generally a blower will get rid of it all (or at least blow it into a nook and/or cranny where it might stay out of the way for a while).

Agreed. My K20D innards has a sticky pad below the sensor which is supposed to collect the errant dust etc. The K20D shakes rattles and rolls the sensor on power up. The body is weather sealed so dust is kept to a minimum anyway.

arthurking83
03-11-2008, 6:19pm
try the same shot at f/29 and see if there is any 'ingrained' dust on your sensor.

These larger spots easily move around(as has already been stated) by the natural forces that deposited them there in the first place.. but as time wears on, smaller dust particles 'attach themselves' to the sensor, in a harder to remove manner(usually by cleaning with a sensor swipe of some kind).

The standard in camera sensor cleaning routine is designed to remove these more obvious dust particles.
I used to use canned air on my D70s to remove them.

wideangle
04-11-2008, 5:45pm
Yeah, the same shot at f29 can show the above spots, and then in others it doesn't. Still stumped as to why sensor dust looks like this, of the sort I have never seen in any other sites/posts?!:)

wideangle
07-11-2008, 10:42pm
My camera doesn't have auto sensor shake/cleaning so can only guess that it would be moving around naturally. All I can think is that I am 'unique' in that I've never come acrross any marks like them?)

Astroman
08-11-2008, 8:23am
I have had small grass seeds and all sorts moving around on and near my sensor, latest one was a hair from my dog had got inside and was moving about, with the type of photography I do, taking many exposures in one hit, the hair was obviously moving, some outdoor sensor cleaning did the job, but not recommended... I shook the camera with mirror up and lens off until the dust etc fell out, the hair was still there but I was able to get my fingers onto it to pull it out.

wideangle
08-11-2008, 9:09am
I have had small grass seeds and all sorts moving around on and near my sensor, latest one was a hair from my dog had got inside and was moving about, with the type of photography I do, taking many exposures in one hit, the hair was obviously moving, some outdoor sensor cleaning did the job, but not recommended... I shook the camera with mirror up and lens off until the dust etc fell out, the hair was still there but I was able to get my fingers onto it to pull it out.

Did the grass seed look like the above specs or soft out of focus ones?

Astroman
08-11-2008, 9:26am
yeah they did look like them, not anymore though.