Help with photographing a painting

Hi @knight427 ,

I did something almost identical to this a while ago for an artist friend. She wanted a color correct electronic copy, she uses very vibrant colors and wanted these reflected in the images.

This was my setup - sorry, no photos.

• A constant light source at a distance on either side of the artwork. This helped reduce any highlights that may have been picked up on a glossy surface edge - her artwork was an oil based painting, so had some texture.
• Setup the artwork to be perfectly square and in plane to the camera.
• Camera in portrait mode to get the maximum resolution. I used my 5DsR and EF100 f2.8 macro at f11. This allows for any slight "out of plane" corners to still be sharp. For your use, maybe the RF70-200 would be best, but try the 24-70 as well.
• Setup the image to include the frame and a small amount around the outside for stitching, and allowance to crop back later.
• Optional: First frame, on the lower left side I had a colorchecker passport (https://calibrite.com/us/product/colorchecker-passport-photo-2/). This allowed the image to be color corrected in post processing.
• Remove the colorchecker for the first panoramic frame.
• Overlap photos by around 30%.
• When I did mine, I kept the camera fixed and moved the target artwork perfectly horizontally along a shelf or easel. This meant I didn't have to find the nodal points for rotating the camera, and removed the parallax error that can result. It did mean I had to be extra careful to keep the image square to the camera.

I used Lightroom to create the color correction (the colorchecker had software plugin for Lightroom) and applied the color profile to the rest of the stitching process.

Hope this helps.

If you want the brushstrokes to be more noticeable, you'll want to use a wider focal length I haven't used the Tamron lens, but I do know the RF 24-70mm should have the least distortion slightly past 35mm but before 50mm, but if you shoot RAW and do 24mm on that lens, the software conversion should be fine. As far as lighting, with this situation, photographing it in the mom's home with whatever was the usual lighting situation according to your friend. Failing that, having it lit primarily from a large window will probably be the best and cheapest choice for getting it even enough. if you have lighting equipment, I would set it to be no more than 20% stronger than the light from the window. Of course this is only my way of thinking.
What @AUGS wrote is also good. If you have time, it's best to try some variations, because everyone has different ideas about what looks best.

Use a mirror to get the camera and artwork in the same plane. When you center the camera in the mirror reflection you are perfectly aligned. You'll need a mirror large enough to align the center of the artwork. Highly recommend a macro like the 100L for this work - it did a great job for me. You want a lens that minimizes distortion. Agree with moving the artwork in the same plane and not moving the camera - it also keeps the lighting consistent. Second the use of the color check for accurate color reproduction. Don't use a point light source, large windows or softboxes at an angle are necessary to get even lighting without harsh reflections.