Focal distance used in Photometric Color calibration?

New Update -

I was finally able to get the image to plate solve, I made a selection box around M6 in the image, made sure I was in linear mode and then went into Photometric Color Calibration and searched for M6 and Siril was able to plate solve, I didn’t change the focal distance, just used what it found. The color calibration looked much better. Hooray!

Maybe M6 was just a better object to search for? Before I was trying the star 45 OPH.

So, I’m all set now.

Hi Folks,

I ‘m struggling to get Photo Metric Color Calibration to plate solve with an image I took with a 50mm lens on full frame DSLR. When I click on “Get Metadata from Image” it fills in the correct Focal distance = 50mm, and the correct Pixel size = 5.97um for my camera and lens. However, I can’t’ get it to plate solve no matter what I try.

The image has been cropped and I am wondering because of that I need to change the focal distance to account for the image being cropped. Does cropping need to be reflected in the Focal distance?

Does anyone have any tricks on getting a wide filed image to plate solve so that Photometric Color Calibration can be used?

Nick L