350D: pixelated images

[markn7]

interesting!! i think i'll have a look at the photo on another monitor. thanks graeme.

 

[Graeme Cogger]

interesting!! i think i'll have a look at the photo on another
monitor. thanks graeme.

Try and find a CRT (if you can!) as they should be better in that area.

 

[markn7]

I think I'll stick with what I've got. I really only have had this issue with a very few photos. Most of the time all is very well. I will check a very good monitor. If the issue isn't there, I'll know its just the monitor and ignore it on the few occasions it happens. If it is still there, I'll know its exposure related and I'll have to think about using exposure compensation when I have a dark subject against a light background.

 

[Blue II]

Instead of posting the picture itself, can you take a screen capture of the problem in PS, then post the screen capture? That way, we should see exactly what you see.

--
Steve
Digital Rebel
50 f/1.8 Prime
18-55 Kit Lens
70-300 IS Lens
24-135 Tamron Lens
Sigma EF-500 DG ST Flash

 

[markn7]

Unfortunately I don't know how to do that.

 

[Blue II]

Just hit printscreen to capture to memory, then open a new PS file and paste it in. You can then crop out all the borders, if you want. Save as a jpeg and post.

--
Steve
Digital Rebel
50 f/1.8 Prime
18-55 Kit Lens
70-300 IS Lens
24-135 Tamron Lens
Sigma EF-500 DG ST Flash

 

[markn7]

Mmm.....having had a look around I can't find printscreen.

 

[Blue II]

It's on your keyboard, next to your scroll lock button. If you have a Mac, I don't know if you have it or not.

--
Steve
Digital Rebel
50 f/1.8 Prime
18-55 Kit Lens
70-300 IS Lens
24-135 Tamron Lens
Sigma EF-500 DG ST Flash

 

[Gordon Pritchard]

On a Mac you hold down "Command" and "Shift" then hit #3. That will take a screen snapshot and create a file on your desktop "Picture1.png" Which you can open in PShop.

best, gordo

 

[markn7]

Thanks Gordo, got it now:

 

[Gordon Pritchard]

Oh, I forgot to add...a quick and easy way to see if your screen is showing you all the tones in your image is to create a tonal test target. In PShop create a new image in Grayscale mode. It should be about 10" long by 2" high at 100 dpi. Click on the foreground/background color menu option to make sure the foreground and background colors are indeed black and white. Then create a vignette from black to white in the 10" direction - "dither" and "transparency" should be Unchecked (off) Then go to "Image" ---> "Adjustments"---"Equalize"

Then go to "Image" ---> "Adjustments"---"Posterize". Enter a value of 21. Voila! You now have a scale from black to white divided into 5% increments. (You can use the "Show Info" dialog to confim values.

If your monitor is set up correctly you should see the black as black and the white as white and you should be able to see each 5% step from 0% to 100% (use the Show Info to confirm). If you can't then the display is not showing you what is in the image correctly. Then do a "Mode" convert to RGB color. Again, you should still see all steps. Also the tone steps should still look neutral gray.

If your screen passes this little test then you can believe that it is showing you what is tonally in your original image.

best, gordo

 

[markn7]

I set up the monitor with the Spyder2 calibration system which, during the set up, displayed two sets of strips (blacks and whites) which I supposed as sets of blocks. All seemed well with that.

 

[misha]

Instead of posting the picture itself, can you take a screen
capture of the problem in PS, then post the screen capture? That
way, we should see exactly what you see.

--

I think what you see would still depend on each person's monitor.

--
Misha

 

[misha]

I set up the monitor with the Spyder2 calibration system which,
during the set up, displayed two sets of strips (blacks and whites)
which I supposed as sets of blocks. All seemed well with that.

I looked at your photos on a Samsung LCD monitor and a Dell laptop screen. On the monitor I do not observe any issues, on the laptop screen I see what looks like posterization - "stepped" transitions in dark areas. Probably the reproduction on the monitor is more correct.
--
Misha

 

[Blue II]

the bottom left part of the picture, on her shirt? If so, I see what you're talking about and can now see it in the original picture, but not as obvious. I think the original may have been a smaller shot. Not really sure what it is. Does it show up when you print it?

--
Steve
Digital Rebel
50 f/1.8 Prime
18-55 Kit Lens
70-300 IS Lens
24-135 Tamron Lens
Sigma EF-500 DG ST Flash

 

[markn7]

yes, thats it. and its also below the collars. misha describes it very well. i've only printed them 7.5" x 5" and thats too small to see the effect.

i took other photos on the same evening in particular a girl wearing a black coat but this time against a blue background and they came out very well. the sony shows great gradations in colour and texture on the black coat. and apart from the photos taken that evening, i've never had this problem with the 350d and the sony monitor. all other photos are very crisp.

 

[Jason Hutchinson]

I've only read a few of the posts but I read that you saw this on a laptop and an external monitor. That is not a good test, because if you've got a calibration issue (I bet you've calibrated your system) causing what you see (and I don't see it) then it will exists out of the video card and affect both the LCD and external monitor.

I've seen calibration cause more "pixelization" problems than anything else. I saw this on some of my PCs too after running Adobe gamma, so it's been removed. The interesting thing is the pixelization you're referring to (at least on a PC) was evident to others (say on this board) if you took a screenshot, but if you just saved the file to the disk (like I bet you did) nobody will see it.

So, I'd recommend two things.

1) If you've calibrated, disable the calibration temporarily and see if the problem goes away

2) Take a screenshot (or heck perhaps a photo of your screen) to show us what you're seeing.

Jason

 

[DocDAT]

as it is caused by the LCD panel, not the image output by the graphics card. So printscreen won't show the dithering/pixelation.

On my CRT the images show absolutely no pixelation, only a tiny bit noise.

 

[ohyva]

hi

the monitor is fine. the effect is visible on both my ibook and
external monitor.

Then I propose you check your monitor settings. If all the monitors show the same, the problem is likely in the computer side - either in setting or in failuer of the HW.

I cannot find any such "artefacts" you describe in my PC monitor - Eizo LCD driven at 1280*1024 32b truecolor.

 

[ohyva]

either calibration not done correctly (or the calibration system is not functioning properly) or just poor HW in which case the calibrated profile may try to drive the display card or monitor in some of its extreme setting. But with Apple I do to believe the latter one, as I have seen this more with some low cost PC HW. I though have not newer use Apple so my "expectations" is based on the reputation of Apple as "system for graphical/artistic work".

I've only read a few of the posts but I read that you saw this on a
laptop and an external monitor. That is not a good test, because
if you've got a calibration issue (I bet you've calibrated your
system) causing what you see (and I don't see it) then it will
exists out of the video card and affect both the LCD and external
monitor.

I've seen calibration cause more "pixelization" problems than
anything else. I saw this on some of my PCs too after running
Adobe gamma, so it's been removed. The interesting thing is the
pixelization you're referring to (at least on a PC) was evident to
others (say on this board) if you took a screenshot, but if you
just saved the file to the disk (like I bet you did) nobody will
see it.

So, I'd recommend two things.

1) If you've calibrated, disable the calibration temporarily and
see if the problem goes away

2) Take a screenshot (or heck perhaps a photo of your screen) to
show us what you're seeing.

Jason