Fine art repro is an art and a science. Back in the day when I had a repro studio, I polarized the lights and the camera lens. One trick to bring out texture is to rotate the gel on one of the lights a bit so that just enough texture comes through. It's a good idea to shoot the artwork with a fully cross-polarized setup first and then take another exposure with one gel rotated--maybe 45 degrees. Take the two photos and stack them as layers in Photoshop. Then blend, using luminance, to bring up the texture.
I was fortunate to have a Hasselblad CF39-MS back mounted onto a custom pancake camera. My main lens was a 72mm Digitar (with an electronic shutter) set in a helical mount. Hasselblad's Truecolor profile was better than any of my profiles. I always set Phocus to process the FFF files in "reproduction" mode. The files were flat, but color sensitivity was linear. That gave me a lot of flexibility when it came time to work on the files in Photoshop.
It is often impossible to make a 95% accurate reproduction. The artists who mixed and matched different brands of paint made it difficult. Also, some oil paint and acrylic paint colors are out of gamut. And back in the day, I used Eizo sRGB monitors. So that's where the science came in. I learned how to use numbers to make adjustments. I often worked by the numbers in LAB and would then often dance back and forth between different color spaces (this requires a good working knowledge of sRGB, aRGB, CYMK, and LAB so as not to lose data).
And of course printer pigments are not the same as paint pigments. So it can be a challenge to manage color throughout the workflow. My pickiest clients were nonprofessionals. Most professional artists who sell their art (originals and reproductions) generally "get it" and will accept "pleasing color" rather than super duper accurate color.
If a client requested 95% fidelity, I billed color matching at $125/hour. For awhile, I was happy earning $$$ tinkering around with an amateur's pride and joy (I serviced clients who were able to afford it. I mostly turned down jobs form starving artists, students, and extremely naive people). But eventually, despite the $$$, I started referring picky, picky clients to my competitor. Funny thing, my competitor would send his picky icky clients over to me.
My best clients were businesses, universities, and archivists. I enjoyed working with professional artists too. I treated my clients with respect and let them decide how much they wanted to spend on accuracy. It's the last +/- 5% that often eats up 90% of a budget. Charcoals, chalk pastels and watercolors are much simpler to work with.
I eventually stopped making canvas prints. Fortunately, most of my repeat customers were strictly interested in digital files or prints on fine art paper. Soon after that, my restoration business took off and I made a business decision to get out of reproduction altogether. It was a wise decision.
It takes thousands of hours of experience to get extremely proficient/efficient in this type of work. I stuck with it for a few years before it became profitable. It's a good idea to keep a couple printers up and running.
