Help ! I have ickies on the canon 300D

[seeker372011]

Not that I am doing any imaging right now but I have found to my horror :scared2: :scared2: :scared2: that I have two big(!!) dark stains on all images with the Canon..this has happened recently don't know when...any suggestions on what do ?
TIA

Narayan

[ballaratdragons]

Buy a Kodak Camera!

[trufflehunter]

Condensation on the CMOS sensor? Only thing I can think of...

[[1ponders]]

Hi Narayn, run through the sensor clean process. It'll lock the mirror up so you can see if there is anything on the IR filter covering the chip. If there is you might have to clean it :scared: If there is nothing obvious then maybe as Wayne says there could be condenstion between the CMOS and the filter.

[Striker]

I'll give you $500 for it.

[trufflehunter]

LOL big time @ Striker! you're incorgible...incrogible...incorogab le... ****** hopeless!:P

[acropolite]

Might just be dust as well, do a google on cleaning techniques; apparently the filter in front of the sensor is very easily scratched and make sure you have a fully charged battery before doing the clean..... Then again it might be a better idea to sell it to Striker and then I could buy it from him for $300 two weeks later and convert it for dedicated astro use...:P

[tornado33]

Howdy
Could you open the shutter using the sensor clean thing and use a bright torch to look closely at the sensor and see if theres a visible mark on the sensor. Could you also post up an affected image.
It seems that if it is a stain rather then a single line its not a scratch or dust, perhaps some oil or somthing somehow got on the sensor window. You cant remember exactly when it happened, or what you were using the camera with when the first affected images started happening?
Scott

[seeker372011]

I'll post an affected image later tonight when I get home

It is definitely a stain not a line or a scratch..just dont know when it happened..could be condensation as suggested by Wayne and Paul but whatever it is, its been there for a while.

No Striker, I am not tempted by your generous offer :D

[seeker372011]

here is an image of the antares region... would have been a nice picture had it not been for the the two dark stains

[Striker]

I see what you mean Seeker....you also have 2 weird looking arrows to get rid of aswell.

[acropolite]

Might also be mildew/fungus if the camera has been stored with mousture on the sensor.

[[1ponders]]

When you find out what they are, let me know, I've got a couple of those as well. I've been considering taking some flats to try and remove them.

[beren]

I had a similar marking as well a while back , followed the directions in my manual with locking the mirror and gave the IR filter a burst with a lens blower , it did the trick . If the blower doesnt remove the particle it may be best to get it serviced then risk physically touching the filter .

[gbeal]

I'm with Beren, and had mine properly serviced recently (it is a Nikon D100 though, not Canon). While cleaner, and my wallet lighter, it still has the odd blotch. If you want to be rid of them get it done properly. Then if (like me) there is still the odd bit, do the Ponders thing, and flat it.
Gary

[gbeal]

Forgot
Striker was a bit high. There was a used 300D on Astromart yesterdya, for US$350 I think. Even that was too high for a Nikon owner to consider jumping ship.

[seeker372011]

for that money why not buy it and get rid of the IR filter..sounds suss though

[Sausageman]

Maybe you have just discovered 2 new dark nebulae...heehee.
Mike

[acropolite]

Gary wrote Yeah a Kodak is about the right priced step up after a Nikon... :lol2:

[tornado33]

They look like large dust particles, I too, recommend using a blower brush without the brush on. If that doesnt work you could risk using one of the new CMOS cleaning kits around now in photographic shops but if u do follow the instructions exactly. Ive seen kits that consit of disposable sterile swabs (dust free) that you wipe once across the sensor then dispose of,single use so that dust collected doesnt cause scratching.
Here is some info on sensor cleaning http://www.luminous-landscape.com/essays/sensor-cleaning.shtml
some more at http://www.bythom.com/cleaning.htm
When I change lenses I always point the camera down and do it as quickly as I can and preferably indoors or at least out of the wind to try and reduce chance of dust getting in.
I hope u get a speedy return to dust free imaging :)
Scott

[iceman]

ah lovely dust! Time to start taking flats, if you can't rid yourself of them!

[seeker372011]

Thanks Scott.

I tried the puffer and it may have just worked. Now need to star test once the rain stops to make sure.

Narayan

[tornado33]

the best way to test for dust is to put on a normal lens, stop down to min aperature, eg F22, point camera at white (or at least evenly coloured) wall, or the blue sky, take a pic (flash or ambient light doesnt matter), with such a small aperature ANY dust particles will show up like a sore thumb, its the ultimate acid test for sensor dust.
Scott

[EddieT]

Hi all,
Although it's good practice to maintain clean optics, it's not always possible to have them spotless and not a good idea to continually clean them. In my opinion, once a year would be extreme for internal camera optics, though using a blower only can be done as often as you want.

It doesn't usually go over well for some reason :), but the practise of flat fielding exists valid reasons and the removal of inevitable dust spots from images is one of them.

Just a suggestion! :)