Strange Noise with my 5D Mark II

[thierry_dehove]

<p>Hi Guys<br>

I just did some photos for a Yacht and I discover that I have suddenly a weird noise on all my photos for example the screen capture http://www.thierrydehove.com/noise-5d.jpg of one of my photos 100% in photoshop photo taken with my 17/40, ISO 50, 17 mm, f 5,6 at 1/320 sec<br>

do you understand why ?<br>

Thanks a lot for your help</p>

[agustin.benencia]

<p>Hi, that's not noise but chormatic aberration. Easily fix with almost any software. Agustín</p>

[PuppyDigs]

<p>Optical artifact and normal for a wide zoom like the 17-40. All lenses suffer some minor chromatic aberrations, especially under high contrast, but better corrected primes tend to have less. Like AB said, it's gone with a click or two in PS.</p>

[tudor_apmadoc]

<p>I agree with the chromatic aberration - I've been using DXO to process the raw files, it will automatically fix this. It picks up the camera body type and lens from the exif and knows how to handle the aberration for that combination.<br>

Tudor ApMadoc<br>

http://www.apmadoc.net/Photos/Tudors_Gallery/index.html</p>

 

[guy_ivie]

<p>If you're shooting RAW and using Lightroom, you have the tool you need to fix the chromatic aberration. Go to the Detail tab in the Develop module; it's below Sharpening and Noise Reduction.</p>

[martin-s]

<p>Thierry,<br>

<br /> yes, this is chormatic aberration and, as mentioned, can be easily corrected in software.<br /> There is something else though going on here… if you look at the dark cushion, you can also spot a faint halo effect. Also there isn't any trace of CA at the edge of the tray.</p>

<p>I wonder what software settings were used in developing that image.</p>

[steven_f1]

<p>I have seen similar artifacts when I was just getting started with digital and and was shooting mainly .jpgs at the time. I think that in high contrast situations jpg compression my cause strange colors when the light and dark colors are averaged. This would also explain why it only occured near the the pillow and darker area of the cair. Note there is another area in the lower left near the arm rest and seat back cushon. I have not seen this since I switched to raw. </p>

<p>Most of the time when I see CA is a blue or purple. It is blue at the top of the pillow but at the bottom near the table it appears orange. </p>