Chromatic aberration help

Heitz · Sep 18, 2011

Hi, This is from a Nikon 50mm f1.8G. Exposure was F/1.8, 1/1600, ISO 800. I'm seeing some very noticeable chromatic aberrations. What is causing this? The high(ish) ISO? My reviews of this lens before I bought it suggested chromatic aberration wasn't bad. Thanks.

clanthar · Sep 18, 2011

I'm going to assume that's an enlarged area in the photo. That's really not too bad -- I've seen much worse including from lots of Nikons. Given that you're shooting the lens wide open I'd say you're within standard performance limits.

Joe

Patrice · Sep 18, 2011

Why did you shoot at such a high iso when it seems you have lots of light. Rare is the lens that is at its best wide open.

2WheelPhoto · Sep 18, 2011

I sold my 35mm f/1.8G for the same reason, aberration.

AgentDrex · Sep 19, 2011

Correcting and Preventing Chromatic Aberration | Tutorial9

2WheelPhoto · Sep 19, 2011

You can correct some but not all of it in PP.

clanthar · Sep 19, 2011

There are four levels of possible correction for CA in Post.

1. As noted in the article Drex posted you can use Photoshop's Lens Correction filter on a JPEG file.
2. You can use Photoshop or similar software to painstakingly hand edit it out.
3. You can also use Adobe's RAW converter in either Photoshop or Lightroom with a RAW file.
4. You can use the RAW file converter supplied by the company the made the lens.

Results:

1. Mediocre at best. If the CA is bad then piss poor at best.
2. Mediocre at best and way too much work.
3. Excellent results with 90% plus CA removal and that's when it's bad.
4. 99% plus removal of all CA including bad CA. I'll give 2Wheel 1% just cause I don't want to get into an argument.

Here's an example:

Screen shot of 200% enlargement of the upper right corner. 24-105 zoom at the 24mm end and the upper right corner is out of DOF. World's best zoom lens would produce CA under this condition and this is not that lens. CA is bad. CA correction in Canon's DPP is OFF -- red box.

This is a one click correction. All I did was check the box for CA correction in DPP. If you still see some residual CA, that can also be removed with the fine-tune controls in DPP. I didn't do that here because I wanted to stress that this level of correction was 1 mouse click.

NOTE: ACR, Lightroom does nearly as well and can remove well over 90% of even bad CA.

The catch: You have to start with a RAW file. If you have CA in a camera JPEG, you can't do this.

Joe

2WheelPhoto · Sep 19, 2011

99% plus removal of all CA including bad CA. I'll give 2Wheel 1% just cause I don't want to get into an argument.

Thanks, I use lightroom and shoot RAW and 99% (for any and all CA i n all pics) is a forgiving number, but for the sake of not arguing I'll agree too.

I happily scrapped my 35 1.8G over its glaring CA and replaced it with a better performing lens, and kept LR3 and my RAW preferences intact

clanthar · Sep 19, 2011

2WheelPhoto said:
99% plus removal of all CA including bad CA. I'll give 2Wheel 1% just cause I don't want to get into an argument.

Click to expand...

Thanks, I use lightroom and shoot RAW and 99% (for any and all CA i n all pics) is a forgiving number, but for the sake of not arguing I'll agree too.

I happily scrapped my 35 1.8G over its glaring CA and replaced it with a better performing lens, and kept LR3 and my RAW preferences intact

I do not have actual hands on test results for this, but I'd check to see if Capture NX does a cleaner job than LR when used with OEM lenses. Glad we're not arguing.

Joe