problem with my images edges

[trr810]

I recently noticed on some flower photos taken w/ my portable studio a sort of aberration on some of the edges of my subject. I checked photos taken outdoors and this appears as well. I'm lost as to what is causing it. In most photos is shows as a bluish halo at the edge.

Attached is an example of one photo. Does anyone know what could be causing this?

I have a Canon EOS Rebel T1i DSLR w/ a EF 28-135mm lense.

[jeff.amadon]

Could be Chromatic Abberation, a common lens annoyance, but it's odd against a black background - usually I see it against the sky or a white BG. It can be fixed in post (ACR has some sliders for it)

Is this RAW or JPG? If the latter, maybe your camera is doing some weird over-sharpening.

[OsmosisStudios]

Chromatic Abberations occur in high contrast areas, where one is very bright (the petals, in this case). It usually manifests itself in the sky when it meets tree branches.

Are you using a close-up filter on this lens?

[trr810]

Thanks for the help. It is a JPG and w/out close-up filter. Only a UV haze filter.

[trr810]

Jeff, you mean the over sharpening is a fluck or there is a way to adjust it? I have some wrong setting. I also think it must be something to do with the camera processing the photo because since it happened on photos taken outdoors and not in a studio, so is not the lights I use in the portable studio.
Could shooting RAW help?
Sorry, what is ACR?

[Doug Pardee]

This is almost definitely lateral chromatic aberration, which comes from the lens. The giveaway is that it is only in one direction.

You should be able to fix this in Digital Photo Professional, which came with your camera. There are lots of other post-processing tools that can take care of it, too.