This is the weirdest thing - Help Needed

[mikew09]

Tonight I I had a heart flutter with my new 50D. I thought I had a dead pixel in the sensor.



I took some photos as it got dark tonight - iso playing with the 50. When I uploaded them I noticed there was what looked like one pixel was white against the dark background. So took some more test shots and it appeared really bad in some and not hardly noticeable in others. I was on the vurge of taking the camera in on Monday to enquire about the issue.
The photo above has a star around the issue, a bit harder to notice but more prevelant in the full raw image. Now the weird part.

This evening I was using my 50D with the 70-200L when I discovered this issue.

For waht ever reason, my workflow brought up some photos I took in Sydney a month or so ago and there I see the same issue.
What tha - then I realise the Syd shots were taken with my 400D and Tamron 17-50. This made me happy as now I realise my shiny new 50 is not at fault.

The other odd thing is, I see the dot in PSE7 until I go to edit and the raw viewer does not show the dot nor do edit. I first noticed the dot when I opened the images in Digital Photo professional and I think this may also introduce the anormality back into the raw file. If I save from DPP it actuall saves the white dot to the jpeg.

If I open the raw in PSE7 and save it to jpeg I do not see it in either raw or the saved jpeg. I have tested my monitor and there is no dead pixels.

I have no idea but this is driving me crazy. I also now notice that image noise seems to show much worse in DPP than in PSE7 and now I think DPP has been giving me a phase impression of how much noise are in low light photos with my 50D.

I hope I have explained this clearly and hope someone can help - it is driving me insane. NOTE: the dot may be a bit hard to see in the reduced size jpeg but it is in the middle of the star.

Mike

[ricktas]

looks like a hot pixel. Dead pixels are usually black, hot pixel's are white or R/G/B.

Now the good bit. You may be able to take the camera back, or at the least get it fixed under warranty, but my guess is they would do exactly what you can do at home.

It is called pixel mapping

Take the lens off
Place the body cap on the camera
Cover the eye cup
Go to the menu
Put the camera in manual cleaning mode and leave it for a minute or two

This process 're-maps' the pixels and should fix the issue.

[mikew09]

looks like a hot pixel. Dead pixels are usually black, hot pixel's are white or R/G/B.

Now the good bit. You may be able to take the camera back, or at the least get it fixed under warranty, but my guess is they would do exactly what you can do at home.

It is called pixel mapping

Take the lens off
Place the body cap on the camera
Cover the eye cup
Go to the menu
Put the camera in manual cleaning mode and leave it for a minute or two

This process 're-maps' the pixels and should fix the issue.

Hi Rick, that is interesting to know. My thread is maybe a little confusing, I first thought it was a dead pixel or hot pixel too. But the oddest thing is, it appears exactly the same in photos taken on two different camera's (my 400D & 50D) with different lenses was used. It is really odd - also varies with software used.
Only noticed it when using the canon Raw software at first. I was thinking it was might be a problem with the base template that the sofware might use when rendering the RAW photos - what do you think?

Thanks for the other tip on hot pixels though, worth while knowing.

Mike

[mikew09]

Hey Rick,
I have another question for you mate - don't you sleep at all :-). I am on here some weird hrs at time due to shift and oncall work times AND you are always online. I don't know how you do it mate - :-).

[ricktas]

oh, no, I am not always online! My account just makes it look like I am

[ricktas]

Ah. Ok. so it shows up in both camera's. How about this. Check your monitor, it could be a dead pixel in your computer monitor, not the camera's. And cause you probably use the same software to load your photos each time, the spot will appear in the same place on each photo.

[mikew09]

Ah. Ok. so it shows up in both camera's. How about this. Check your monitor, it could be a dead pixel in your computer monitor, not the camera's. And cause you probably use the same software to load your photos each time, the spot will appear in the same place on each photo.

Yea, I will try that. I have read that a proper test image should be used as monitor pixels may only show a problem under certain conditions.

Googled about this this morning and one forum suggested that a flakey video card can produce similiar effects - looked like a pretty dogey forum though - one of those ones that is not monitored and members are obusing others for what they say are stupid comments.

I think I will try my daughter monitor to see how it goes.

Thanks Rick - more to follow soon.

[mikew09]

Still puzzled. I have a theory.
Photo rendering applications have a framework they use to render this pixel there etc. If the base framework had some corruption in the template for rendering it may not be able to read in the raw data correctly.

I hve tried another monitor, what looks like a hot pixel apperas in any photo with dark or close to black, in the same place and if rotated follows the photo. If appears in photo taken with different lens on my 400D or 50d. If I open a new raw image in PSE7 I don't get it, however; if I open in DPP it will remian until I open in the PSE7 editor - very strange. My only concern is that it may corrupt my photo data. My other thought is faulty video card that does not render well with the DPP profile.

Any one else had a siliar issue.

Mike

[ricktas]

Does sound like DPP is the cause of this. Maybe an uninstall and re-install.

[mikew09]

Does sound like DPP is the cause of this. Maybe an uninstall and re-install.

I am thinking something a little more drastic - maybe time for my annual rebuild of my PC, dammed windows and the junk yard they call registry :-).

Need move is to install DPP on my daughter laptop and see if I get the same issue.

Thanks for you time Rick.

[ricktas]

download "glary utilities" - it is free and run it on the PC. Then go to modules in glary and do a registry clean up and defragment. Brilliant programme! But as this is only happening in DPP, uninstall and re-install should fix it

[mikew09]

Thanks Rick, good suggestion - I have downloaded and will give this a go tonight after work. Excellent Windows tool by the looks.
I wl un-install DPP, reistry clean and install again. I reckn that will do the trick.

Thanks again.

[mikew09]

download "glary utilities" - it is free and run it on the PC. Then go to modules in glary and do a registry clean up and defragment. Brilliant programme! But as this is only happening in DPP, uninstall and re-install should fix it

Hey Rick, I just want to sy thanks for your help. I downloaded and installed the utility software and it is brilliant. I think I have fixed my DPP issue but the software also fixed a number of other niggling issues I had, obviously registry related and has helped toimprove performance of my pc.

Thanks Mate - brilliant.