Problem with SIGMA DP1 MERRILL Camera RAW files

Software ART
1

Hello,
I use ART since 2019, and i think it is a very good software.
Thanks for developers and especially for Alberto.
It is the first time i post in this forum, and my english is very bad…sorry

I use ART 1.21.2 with Fujifilm XT5 camera and now, with Sigma DP1 Merrill cameras.
For Fuji, all is good, but for Sigma, the colors are very bad.
for example, this is a JPG of a sunrise:

Capture d’écran du 2024-10-16 20-37-55
Capture d’écran du 2024-10-16 20-37-551000×582 56.9 KB

and this is the RAW:

Capture d’écran du 2024-10-16 20-35-57
Capture d’écran du 2024-10-16 20-35-571000×578 52.5 KB

Can you help me to resolve this problem?
Thanks

1 Like
2

Looks like ART’s missing a black point for this camera.

3

Hi,
Can you share the raw file? Thanks!

4

Hi,
You can download then raw files and jpeg here:

grosfi.ch/Yigv4xTkYt2

Thanks

5

In case you need, you can find DP1 raw files here.
I tried opening some of these raw files using ART built from the latest commit which prevents reading white and black levels from camconst, but the colors still don’t look right.

Screenshot 2024-10-20 at 20.00.36
Screenshot 2024-10-20 at 20.00.361917×665 1.46 MB

6

Thanks, good to know. Indeed the last commit is only a partial solution that fixes the black level, but it looks like we would need at least some kind of flat field correction as well. I’ll try to dig deeper when I have some time. It would be useful to have a shot of a flat field to test (taken following these instructions: Flat-Field - RawPedia)

1 Like
7

Thanks,
I will shot a flat field as soon as possible

8

I thought you had to pretty much use Sigma Photo Pro to process foveon files?

9

Hello
Yes, but on Linux it is not easy. with wine maybe or a windows virtual machine, but i prefer, if it’s possible, to use ART

10

Hello ,
I have made a flat field, with two frosted plastic plate for coaster in front of the camera lens, while photographing in the shade a white paper installed vertically at 50cm, distance set manually to infinity. diaphragm was F2.8, f4, f5.6 f8 f11 and F16.
Click here to download the JPG and RAW files

grosfi.ch/PfKJYGsADmu

Thanks

11

Thanks! It might take a while before I get to do something about it, but I’ll definitely give it a try!