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Flat Artwork Recomendations?

Craig Stocks

Well-known member
I do some reproduction work for local artists, but not enough to warrant great expense. I'm looking for recommendations to improve what I'm currently doing, especially for good color matching.

My current process:

IQ 260 on a Phase One 645DF, Phase One 120 macro, Singh Ray polarizer

Four Alien Bee strobes with polarizing filters. I get quite a few glossy pieces and seem to need cross polarization most of the time, so I use it all of the time for consistency.

Shoot tethered to Capture One 8.2

I include an X-Rite color checker (the 8X10 version) and a printout of the color checker target's RGB values in ProPhoto RGB.

Shoot the art alone, the art with the color checker and a plain white foam core for LCC. Every camera position change gets a new LCC.

Apply the Flat Artwork profile and LCC.

Adjust exposure to ensure around 145,145,145 in the third gray patch (using ProPhoto as the active recipe) typically shoot at5.6. Adjust endpoints to around 245 (white target) and 24-30 (black target). White balance on the light gray target.

Process the art image and the color checker reference image to a 16-bit PSD.

Open in Photoshop. Use a Selective Color adjustment layer to tweak R,G,B,C,M,Y,K values to match the patch specifications (again in ProPhoto RGB). I then copy the Selective Color layer to the actual artwork image.

(I've not had good luck matching the RGB color values directly in C1. I find it very hard, if not impossible to adjust hue rotation and saturation to tweak RGB values toward an expected result. With Selective Color, I can directly adjust the RGB values in the adjustment to get an exact match to the target RGB values.)

Square up the artwork with Perspective Crop.

Sometimes I can re-use settings from a previous Selective Color and sometimes they need tweaked. I assume much of the variability comes from polarizing but color consistency of the Alien Bees may be an issue too.

Overall I feel like I get good results, but it can be tedious, especially tweaking the Selective Color settings. I make prints for some artists and the prints do match pretty well, but I run across quite a few out-of-gamut colors in the paintings that I just can't reproduce.

My goal is a workflow with predictable results and an absolute minimum amount of tweaking based on visual review.

(By the way, I also tried Lightroom / ACR with an X-Rite custom profile and it was not very close at all. The LR profiles seem to be geared toward bold, attractive colors rather than accurate colors.)

Any suggestions on how I can improve my workflow?
 
Well, that is quite a lot more extensive than what I do... in fact your setup is what I might have considered my "dream" rig, since I do art reproductions professionally with half the gear and a 10th the expense of what you have.

Overall I feel like I get good results, but it can be tedious, especially tweaking the Selective Color settings. I make prints for some artists and the prints do match pretty well, but I run across quite a few out-of-gamut colors in the paintings that I just can't reproduce.
And you never will. Some colors that artists use can be way beyond the gamut of any imaging or printing solution, which is why many artists paint over their reproductions to fix colors and tones that can't be reproduced. and don't get me started on metamerism, sub-surface scattering and refraction which complicate things since paint has depth and is opaque.

On a computer, white can never be whiter than 255 RGB or the white of a printer can never be whiter than the canvas/paper itself, but titanium white paint, especially if it's been laid down in layers, can be extremely bright. All you can do is try to preserve the highlights.

Honing in the colors manually and getting feedback from the artist is still the way to do it.

The only thing I can see you improving is switching out your alien bees for something higher-end, like Profoto lights, since they tend to have the best shot-to-shot exposure/temperature stability. Some photographers I know prefer continuous lighting like HID or HMI lights since they [claim to] provide a higher CRI than strobes.
 
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kdphotography

Well-known member
The least expensive but noticeable upgrade for your lights will be the Einstein. They are noticeably more consistent with regard to exposure and color consistency over the AB. You will find it much easier and more accurate making adjustments using the Einstein's digital controls over the cheap AB slider controls.
 
The least expensive but noticeable upgrade for your lights will be the Einstein. They are noticeably more consistent with regard to exposure and color consistency over the AB. You will find it much easier and more accurate making adjustments using the Einstein's digital controls over the cheap AB slider controls.
Anything with digital controls would be an upgrade for a start. I have Hensel strobes because they were the least expensive digital strobes at the time I bought them, the Einsteins were only a rumored product at the time.
 

dougpeterson

Workshop Member
The first upgrade I'd suggest, like Ken, is your lighting. I had four AlienBees when I was in college; great customer service, and very low price, but not the highest quality strobes regarding consistency or durability. Einsteins, or, if you can muster, Profoto/Broncolor would definitely help eliminate illuminant variation.

The next upgrade I'd suggest is the Capture One Cultural Heritage Edition and a set of ISA Test Targets.

The CH version of the software will provide a set of bespoke color profiles which outperform In-Situ profiles (i.e. a profile you as the end-user generate by capturing one target, one time, with one illuminant) or manual target-value tweaking (i.e. playing with curves or HSL to match desired RGB values) with much less work and greater consistency.

The targets will provide you FADGI compliance testing which has become very important in the high-end art reproduction market and the museum/library market, and also provides an excellent benchmark (far better than, say, a Color Checker SG) for measuring and ensuring long-term consistency in your exposure, focus, light uniformity, and white balance.

As Kolor-Picker says you can never reach a 100% match between two people let alone two illuminants. But, by reducing variables and using high-quality hardware/workflow you can certainly get very close.
 

T.Dascalos

Not Available
My recommendation would be to use a multishot back instead, as to avoid colour interpolation. I'm sure a S/H inexpensive Sinarback 54H will do a much better job for reproduction work.
 

Craig Stocks

Well-known member
Unfortunately I bought my ABs before there was an Einstein option. Since I always use them a full power it's just the shot-to-shot consistency that's a potential problem. I should probably do a simple test comparing and validating the four heads too.

Doug - a couple of questions: The CH version has some appeal if the profiles really work for my setup, but I recall it's pretty expensive. I haven't pursued the trial CH version since I'm under the impression that it's more money than I can justify for the volume I do. Also, I'm not clear if C1-CH improves the quality of the end result or just the convenience of getting to a similar result.

If I still need to do manual color tweaking then I'd probably still need to go to Photoshop where I can guide RGB values directly with RGB sliders. Maybe there's a technique to using the color adjustments in C1, but I just haven't been very successful adjusting RGB values with hue and saturation sliders. It would be great if C1 had RGB sliders somewhere, more like Photoshop's Selective Color adjustment.

The ISA target certainly has an appealing form factor by being long and narrow, but I'm unsure of its other advantages. It appears that ISA sources their color patches from X-Rite (their website lists GretagMacbeth as the source) and they're the same color patches on the X-Rite color chart. Having Lab values printed on the target is a nice addition, but only if I'm able to fine tune toward Lab target values directly in C1. Again, there may be a technique I'm missing that makes it easy.

I do realize that it's a very elusive goal. I photographed a poster the other day and even though the color patches match almost perfectly the color of the poster is off by quite a bit. I'm pretty sure it's printed on a paper with optical brighteners, so the whole control scheme is rendered mostly ineffective.

There are probably some simple pieces to the puzzle that I'm missing.
 
There are probably some simple pieces to the puzzle that I'm missing.
This is a discussion I've seen on this forum a while ago and it evolved into something about archival-grade technology and techniques that go beyond the ultimate goal of what we're discussing, which I assume is art reproduction for the purpose of re-printing in a catalog or as a reproduction on canvas.

Realistically speaking, I doubt that after initial color matching anyone will really concern themselves if the shade of blue in one part of the sky in one painting is very slightly off-color. I'm not saying you should settle for "good enough", but you are at the cross-roads where simple art reproduction turns into archival photography, which throws away any idea of practicality. A client artist wants my prints tomorrow, but historical artifacts won't be going anywhere for many years still.
 

T.Dascalos

Not Available
Second thing (after using a tri-color back for capturing) I would recommend, is to avoid strobes... I believe constant lighting (with or without polarisers) is the way to go... I would recommend fluorescent with CRI>97 (similar lighting to what a Cruse scanner is using) at 5500K.
 
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