Trouble seeing red?

[justme_dc]

So I shot a model last night wearing a red silk mandrin collared dress. (the model was wearing it, not me.) The thing is, when I loaded the images into photoshop and enlaged them to 100% I saw what appears to be weird banding/fringeing artifacts at all the edges where the red transitions to another color. Have any of you had similar experiences? I know that reds are sometimes troublesome but this is just weird.

the facts:
10D in manual f11 @ 1/125th, custom WB, Studio strobes, On tripod, L series lenses, large JPeg mode, all image mod settings at factory default.

[Roger_Cavanagh]

This sounds like a problem that Noel Carboni has discussed on the Rob Galbraith Forums. I tried to find the thread, but couldn't. If it is the same thing, it's to do with the JPG compression causing a problem, and you just have to live with it when it happens or shoot raw.

Regards,

[J.A.F. Doorhof]

This could be something we call (in videoland) the Chroma upsampling bug/error.

Where in compression color is compressed into 4:2:0 colorspace where actualy 4:4:4 is normal, so you have half resolution color information next to full resolution Y (luma).

I could imagine that JPEG compression uses a similair concept.

Greetings,
Frank

[justme_dc]

I figured it was a Jpeg aritfact...... That'll teach me to shoot in Jpeg mode..... I think it was the second time I've ever shot in anything other than RAW.....

[robertwgross]

It sounds like what you get from JPEG compression that is too strong.

Back when I got my EOS D60, I simply resolved to shoot everything in RAW format, and then I have full control to sort things out in the computer.

My image editor allows me to store images in ordinary JPEG or else Zero Compression JPEG, so I can control how much detail I want to throw away.

---Bob Gross---