Why this happening to me?

hpolat · Aug 27, 2007

I am new bie and the same problem over and over again.
I am not sure whether I am using high ISO or not (necessary especially when I have no tripod and low light) I got this colorful (red green) layer over my photo, looks so terrible. How can I reduce it? what am I doing wrong ? (don't worry abut out of focus unless it is part of the reason, the problem is all over the picture, I circled the area when you can clearly see it.)
thank you

LaFoto · Aug 27, 2007

Heya hpolat, welcome to ThePhotoForum.
Normally I would say your posted photo is too large for web-showing, and that you should best stick to a maximum width of 800px (when it is a horizontal frame), but with this I accept that your primary goal was to show us the chromatic abberration (only learned this word myself the day before yesterday!

) that you get.

Well, you say you don't know if you work with high iso settings?
How come you don't know?
Don't you set the ISO by hand?

And even if you are unsure, you can still check on the photo's EXIF data to find out what iso your camera was set to.

Anyhow, high iso creates noise, and large as this photo is, I would assume this is the "colour noise" (or more technically "chromatic abberration") that you get from it. If you had shown your photo smaller, I doubt we would have seen that much of it.

LaFoto · Aug 27, 2007

Oh sure!
Your pic was taken at 1/8000 (!) at ISO 3200!
That explains quite much of it then!

glaston · Aug 27, 2007

Wow. Those are some extreme settings you're using there.
Looks like you got some weird shadow artifacts going there judging by what's going on around the problem area.

You've offended the god of color though that's for sure.

I have no suggestions on a solution since I can't really tell what the problem is.

sothoth · Aug 28, 2007

It seems like LaFoto got it right... you took this at a very high ISO and that pretty much guarantees problems with graininess. On my camera, I also get color distortion where patches of the image look too green or too blue or too red. I don't shoot my digital above ISO 100 unless I have to, and even when I have to, I accept that the pictures may end up unacceptably grainy.

I don't know if I see any evidence of chromatic aberration or not but for the sake of argument lets say you have it... that type of distortion is caused by a low quality lens, which refracts light of different wavelengths at different angles, so you get color distortion around the fringes of color transitions. Here's an example from Wiki which is a pretty good one:

http://en.wikipedia.org/wiki/Chromatic_aberration

I'd be willing to be that if you drop the ISO way down (pretty much as low as your camera goes) your problem will disappear, and if you still don't like it, try shooting with a lens that you're sure doesn't have C.A. problems.

Good luck.

By the way, that bird looks pretty fiesty, I'd use a telephoto and keep my distance.

Alex_B · Aug 28, 2007

LaFoto said:
1/8000 at ISO 3200

Nobody needs 1/800 to hold the camera steady ... and the colour noise you get is what one would expect at ISO 3200. It usually shows stronger in the dark parts.

Try to use ISO at or below 800 and use some noise reduction software.

LaFoto · Aug 28, 2007

Oh. I might have got a wrong idea about what "chromatic abberration" really is, thanks for the wiki explanation link, sothoth, so IS there a special word for this kind of colour noise?

Alex_B · Aug 28, 2007

LaFoto said:
colour noise?

yes, it is .... colour noise (

), which is a standard component of digital noise if you want to subdivide it that way. I would not know of any other term.

These fluctuations in the signal are amplified alot since the signal to noise ration is too low at high ISO.

fmw · Aug 28, 2007

Just noise. Cut down the ISO setting to the lowest possible level for the situation. Personally, I leave mine at the lowest possible level for every image. I use a tripod when hand holding isn't enough. The extra trouble is worth it to get better image quality.

neea · Aug 28, 2007

wow 3200. Mine only goes to 1600 unless the rest are hiding in some strange menu.

EDIT: not that i'd ever use them of course. i rarely go over 100 or 200 unless im 'experimenting' lol.

Don Simon · Aug 28, 2007

I use ISO 3200 if I absolutely have to... as they are the images are usable for small prints and they can always be cleaned up a bit with software.

But again, only if I have to.

It should be possible to have the camera limit which ISO settings can be selected by the camera in auto modes... you may want to set it to 800 or lower (and then you can always raise it yourself when necessary).

Digital Matt · Aug 28, 2007

In addition to what has been said I have to say that this image is remarkable in terms of noise for ISO 3200. It's not something I would throw away simply because it is noisy.

Don Simon · Aug 28, 2007

Right, and I'm guessing it hasn't been through any software noise-reduction yet (except in-camera). Turning off the in-camera noise reduction (to retain detail) and then running some NeatImage or NoiseNinja would probably be even better.

Either way the image is certainly useable... its just better to start off with a less noisy image when you can. And you can do that by not using ISO 3200 at 1/8000

... when you could use ISO 200 at 1/500 instead and not have to worry about noise at all.

hpolat · Sep 19, 2007

After reading all the posts I clearly understand the cause, hmm as I said I am a new bee. Now this is the story, I live in Vegas and I have to take pictures always at night. When I set the ISO less then 1600, impossible to take sharp picture without tripod. However I am not even allowed to bring the tripod to most places I am taking pictures. All my night pictures have the same problem (abberation) . Now I am willing to invest money to buy alot better camera and lens, but will the best camera and lens will help me to take picture in lower ISO and no tripod ? in other word, will the camera allow me to take minumum 1/30 and ISO 400 when I am shooting at night to vegas strip ? (I can accomplish this with my camera 1/30 and ISO 1600) (night but there are still light) .. unfortunately tripod is not a good solution for me again I am not allowed to bring tripod most places I take pictures.
I have canon 20d with canon EFS17-85 lens, not a bad camera, and I don't have to zoom much with my shots.

Now another problem I have : when I shoot Vegas strip picture from a distance, either the lights of the ad boards are too bright and picture has too bright OR other way around : ad boards are OK and visible but the picture is too dark, what is the best settings to take shot like that ?

and last question, I have been looking at the lenses, for my use which of these two lens more usuful ? a)Canon 28-300mm 28-300 IS USM L Lens b) CANON EF 70-200mm F2.8 f/2.8 L IS USM OR any other lens that maybe better for the purpose ?

Thank you all, I am very new and don't have much time to learn at least the fundamentals.
Thank you all for your help.:thumbup:

JDS · Sep 19, 2007

The camera you have is not a problem at all - it's a great camera. To get better exposures in less time (Shorter shutter speed), you need a larger aperture to let in more light. But even with a large aperture at night, it's going to be tough to get handheld shots without blur unless you do crank up the ISO as you've done. The downside, as you've learned, is the photo comes out grainy.