PDA

View Full Version : What caused this ... see photo



Bluedog
04-17-2005, 06:45 PM
Seen this (darker circled spots) in a couple of my photos using the Sigma 18-125mm. It doesn't happen in all of them just a few I've noticed. That was shooting facing Southeast with the Sun setting in the Western sky.

http://img145.echo.cx/img145/4222/img04861rk.jpg

jeisner
04-17-2005, 06:48 PM
It looks just like dust on the sensor... It is more noticable in areas of constant colour i.e. the sky and at smaller apetures (higher f numbers)....

My prefered method of cleaning is the Copperhill method (http://www.pbase.com/copperhill/ccd_cleaning)

Bluedog
04-17-2005, 07:01 PM
Well that was @ f/14. Dang dust already on my new XT's sensor ... :confused: ... man I've been extremely careful only swapping the lenses a few times.

edit this:

"That was shooting facing Southeast with the Sun setting in the Western sky."

That was wrong as it was actually facing due east with the sun in the west around 3:00PM to my back.

This one was this evening facing Southeast with the Sun setting in the Western sky:

http://img120.echo.cx/img120/8931/img04983dh.jpg

jeisner
04-17-2005, 07:48 PM
Take a test shot looking at the sky at say f20, we will quickly know for certain if it is dust, as it will really stand out...

gary_hendricks
04-17-2005, 07:54 PM
Looks like dust on the sensor to me. ;)

Bluedog
04-17-2005, 08:07 PM
Will do tomorrow as its dark outside now ... thanks.

Bluedog
04-17-2005, 09:09 PM
or just use the the rubber stamp method in Photoshop, not bad for a first try ... :D

results:

http://img59.echo.cx/img59/1898/img0486medium8wj.jpg

Bluedog
04-18-2005, 09:44 AM
I took this image after blowing the sensor off as according to Canon XT manual ... :o ... but somehow gained a small dust speck on the upper AF sensor that doesn't show up in any photos. Would the Speckgrabber tool help with removing that or don't worry about it?

Taken at ISO 200 TV 100 f/22 of totally cloudy sky and that is an actual photo of the sky:

http://img149.echo.cx/img149/3056/dusttest05075vg.jpg

Bluedog
04-18-2005, 09:56 AM
Here's another @ ISO 100 TV 60 f/22 Focal Length 26mm:

No dust specks that I see but still the pesky speck in my AF viewfinder:

http://img94.echo.cx/img94/7392/dusttest2img05098xj.jpg

LoveOfSelene
04-18-2005, 02:28 PM
Seen this (darker circled spots) in a couple of my photos using the Sigma 18-125mm. It doesn't happen in all of them just a few I've noticed. That was shooting facing Southeast with the Sun setting in the Western sky.

http://img145.echo.cx/img145/4222/img04861rk.jpg

Are you using a filter in front of your lense? To me it looks like you got specks of water on it or the lense itself.

Loveofselene

Bluedog
04-18-2005, 05:14 PM
Nope no filter and the lens is clean. It had to be the sensor as I can't get it show back up after blowing it off. Before any image that didn't have a lot of subject @ an f-stop above 9 it was starting to be visible.

ReF
04-18-2005, 11:20 PM
Here's another @ ISO 100 TV 60 f/22 Focal Length 26mm:

No dust specks that I see but still the pesky speck in my AF viewfinder:

http://img94.echo.cx/img94/7392/dusttest2img05098xj.jpg


if your see it through your viewfinder only, then it's probably on that little panel right above the mirror. might as well check the mirror too. btw, i don't see an image for post #8. does anyone else see it?

Bluedog
04-19-2005, 05:05 AM
if your see it through your viewfinder only, then it's probably on that little panel right above the mirror. might as well check the mirror too. btw, i don't see an image for post #8. does anyone else see it?

"little panel right above the mirror ... that is exactly where it is, about a third of the way below far right AF sensor toward bottom. It doesn't effect anything just an annoying small speck and for post #8 is a near perfect white clouds photo shot at f/22.

This gives a better idea that I was successful in removing the dust particles again at f/22:

http://img254.echo.cx/img254/7497/dusttest305179mw.jpg

Thanks for the feedback guys

gary_hendricks
04-19-2005, 06:51 PM
Did you manage to clear out the dust/water from the lense, how'd you do it?

Bluedog
04-19-2005, 08:58 PM
I used a blower bulb less the brush. Locked up the Mirror and blew inward while holding camera upside down blowing several times until the image came out clean looking with no visible spot I could see. I think when the Mirror locked up is when the dust particle got on the upper AF glass that won't come off although its only visible in the viewfinder and not imposed on any images ... more annoying knowing its there than anything and it won't let loose.