Really bad chromatic aberration with my 7D

I purchased my Canon 7D earlier this year. I've used it a lot although I'm not sure how many clicks there are.

I've been noticing that it doesn't seem to be as sensitive to light as it use to be. I end up having to turn up the ISO, and even if it's at 600, I get extremely bad chromatic aberration. By default, I'm using the 18-135 EF-S lens.

Is my sensor starting to screw with me or is there something I'm missing?

I appreciate the help!

MKerckaert wrote in post #16285946
I purchased my Canon 7D earlier this year. I've used it a lot although I'm not sure how many clicks there are.

I've been noticing that it doesn't seem to be as sensitive to light as it use to be. I end up having to turn up the ISO, and even if it's at 600, I get extremely bad chromatic aberration. By default, I'm using the 18-135 EF-S lens.

Is my sensor starting to screw with me or is there something I'm missing?

I appreciate the help!

CA is a result of your lenses and not your sensor. ISO also has nothing to do with CA, it will just make the CA more noisy.

Exposure is exposure, I cannot see how your camera is less sensitive to light?

Lens.

As above.
Chromatic Aberration is usually because of the lens.

Higher ISO's just make for a more noisy/grainy image, again this has nothing to do with CA.

Especially since you say you "default" to that 18-135.

I'm learning, here, guys.

Is the 18-135 considered a cheap lens? What would be a good upgrade from it?

It could be out of spec if it was banged or something. Not really to do with the lens itself. Do you have a filter on it?

Not really cheap, but it's a long range zoom. That is, 135/18=7.5.
When you get values larger than approximately 3, or maybe 4, then the lens designer has to start using design tricks which are bad for the image quality. To make long range zooms, aka superzooms, with good quality over the entire range is expensive. Canon has made one more recent attempt, in the EF 28-300 mm f/3.5-5.6L IS USM. Compare the cost to the EF-S 18-135 mm f/4-5.6 IS, and you'll immediately realize that your lens design employs more shortcuts. Of course, the range is more like that of the EF-S 18-200 mm f/4-5.6 IS, but still...

To get two very good lenses, covering approximately the same range as you do today, you could go for the combination of the EF-S 17-55 mm f/2.8 IS USM as a general purpose zoom, and then the EF 70-200 mm f/4L IS USM as a longer range zoom with a very good cost/performance ratio. But they'll cost you more than the camera and lens you already have did together.

Samples of problem images with EXIF intact please.

apersson850 wrote in post #16286007
Not really cheap, but it's a long range zoom. That is, 135/18=7.5.
When you get values larger than approximately 3, or maybe 4, then the lens designer has to start using design tricks which are bad for the image quality. To make long range zooms, aka superzooms, with good quality over the entire range is expensive. Canon has made one more recent attempt, in the EF 28-300 mm f/3.5-5.6L IS USM. Compare the cost to the EF-S 18-135 mm f/4-5.6 IS, and you'll immediately realize that your lens design employs more shortcuts. Of course, the range is more like that of the EF-S 18-200 mm f/4-5.6 IS, but still...

To get two very good lenses, covering approximately the same range as you do today, you could go for the combination of the EF-S 17-55 mm f/2.8 IS USM as a general purpose zoom, and then the EF 70-200 mm f/4L IS USM as a longer range zoom with a very good cost/performance ratio. But they'll cost you more than the camera and lens you already have did together.

Super helpful! Thanks!

Although those lenses are not cheap, but I guess you get what you pay for.

You stated you haven't always had this problem and that the CA has become worse. Why not verify that it is in fact that lens, and send it in to canon if that is the case? There is no need to go hog wild if you dot want or need to, but of course, that is your decision....

MKerckaert wrote in post #16285990
I'm learning, here, guys.

Is the 18-135 considered a cheap lens? What would be a good upgrade from it?

CA is a problem for many lenses, and not limited to cheap lenses. It is an attribute of both cheap lenses and very high quality very expensive fast-aperture lenses alike. Many L lenses suffer from noticeable CA wide-open.

I'd start looking into software processing solutions, instead of throwing away any images you currently have that may be suffering from CA, or spending money on a new lens.

I don't know what software you currently use, but there are tools to help remove CA from fully automated programs with adjustment sliders (Lightroom, latest version of Adobe Camera Raw, I think DPP may even have a tool for this), to completely manual methods (PS) using brushes layers and desaturating the CA.

Yeah I've come up with some techniques in Photoshop, and even tried in Lightroom. I should start shooting more in RAW anyway just to have the flexibility of eliminating it.

Does the 7D have on board lens correction? If not, does the Canon softrware correct for CA?

EDIT: Looks like it does. I don't know if it is automatic like it is on 5D3 and 6D.

http://www.usa.canon.c​om …display/EOS7D_f​irmware_af

Curious to see the same subject, taken from a tripod, at both "default" aperture (whatever you're doing now) and stopped down to ~f/8 or f/11. You say you're using higher ISO, which I'm my mind also corresponds with wider aperture to achieve a reasonable shutter speed. At the longer end, f/5.6 is still "wide open" which is where CA is worst.