DP2M macro moire?

Started Dec 26, 2012 | Discussions
Shop cameras & lenses ▾
rmrcu
rmrcu Regular Member • Posts: 214
DP2M macro moire?

I'm a new Sigma owner and am enjoying my DP2M very much.  However I sometimes  see an image artifact that is annoying:  an alternation of red, green and yellow(?) that doesn't exist in the original subject.  Below is an image processed heavily in SPP, and below that is a crop that exhibits the phenomenon  (look at the vertical 'columns' in the crop).  Anyone know what's going on or what I'm doing wrong?  Thanks for looking.

Sigma DP2
If you believe there are incorrect tags, please send us this post using our feedback form.
guzzibreva1 Contributing Member • Posts: 947
Re: DP2M macro moire?

You are shooting at -1.6 bias which puts you at 326 ISO. You are also getting some underexposure due to the bright sky. When you push the image with SPP the color banding is shown in the darker parts of the image. If you must use a negative bias be sure to use 100 ISO.

Kendall Helmstetter Gelner MOD Forum Pro • Posts: 19,379
Re: DP2M macro moire?

Color noise is something you get with the Foveon sensor if you push the shadows really hard (which I think it is in that case).

If you like raising shadows think about shooting ISO 200, but at +1.0 ev.   Then when processing in SPP move exposure down to fix any highlight clipping, use fill light no more than +0.3 to recover things a bit, and output a 16-bit TIFF file to finish in some other application using a combination of brightness and levels shadows/highlight recovery to restore the overall scene brightness and bring up the shadows more.

You may be able to manage just in SPP if the highlights are not too blown, as fill light also acts to recover blown highlights to some extent.

 Kendall Helmstetter Gelner's gear list:Kendall Helmstetter Gelner's gear list
Sigma 70-200mm F2.8 EX DG OS HSM Sigma 8-16mm F4.5-5.6 DC HSM Sigma 24-70mm F2.8 EX DG HSM Sigma 50-500mm F4.5-6.3 DG OS HSM Sigma 85mm F1.4 EX DG HSM +4 more
rmrcu
rmrcu OP Regular Member • Posts: 214
Re: DP2M macro moire?

Thanks guzzibreva1.

rmrcu
rmrcu OP Regular Member • Posts: 214
Re: DP2M macro moire?

Thanks Kendall.

Bob

Keyboard shortcuts:
FForum MMy threads