Further homage to Mildred Marsh, Cynthia Blake and their fellow colour separators
UPDATE (July 26th, 2021): This post has been changed since it was originally put up in April of this year. It now fully takes into account Eliot R. Brown’s highly valuable post about a visit to the colour separators of the Chemical Color Plate company back in the mid-1980s. My post has illustrations recreating the colour separation process in detail. Elliot’s post was the source of two key details in particular, for which I am very grateful. I wish I’d found it sooner! Well worth a look!
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- Part 1 — Roy Lichtenstein—the man who didn’t paint Ben Day dots
- Part 2 — Halftone dots, Polke dots, more Roy
- Part 3 — CMYK / Four-colour comic book dots vs. RGB dots on screens
- Part 4 — Pre-history, origins—Ben Day in the 19th century
- Part 5 — Ben Day in lithography
- Part 5.5 — French comic strips of the 1880s. Coloured by relief aquatint.
- Part 5.75 — A lithographic protocomic (?) from 1885
- Part 6 — Ben Day meets the Sunday Comics in the 1890s
- Part 6.1 — Tarzan and the Ben Day Dots—secrets of 1930s comic strip colour
- Part 6.2 — Fun With (Mis-)Registration—when colour printing plates don’t line up
- Part 7 — The Birth of the Comic Book,
- Part 8 — 1930s to 1950s: the Golden Age of Comics, and Craftint Multicolor
- Part 9a — 1950s and 60s: the Silver Age of Comics, Part 1
Previously on ‘The History of Ben Day Dots’:
Both sections of Part 9 are about a certain system of colour production — specifically, a system of colour separation — which was used by Marvel, DC and many other US comic book publishers from the 1950s to the 1980s, but not by all. I have called it ‘the nine acetate method‘ or more simply ‘the acetate method‘. It was used for the inside pages of the comics, printed on rough newsprint paper — and by the letterpress method, using relief printing plates, not by offset litho as you might read elsewhere. (Litho printing came to the US mainstream comic books only gradually during the 1980s.) Comic book covers were generally printed on better, whiter, glossy paper — and produced by a variety of different methods, which I’m not dealing with here.
The acetate method involved the hand-painting of up to nine acetate sheets for each four-colour page — a set of three acetates for each of the three colours (excepting black) followed by photographic combination of each set of three acetate images into one negative image which could be used to make a printing plate. (The black printing plate was separately photo-engraved as it had been from the first 1890s Sunday newspaper strips onwards.)
The acetate method was slow and highly laborious, especially compared to today’s computerised methods.
It was a continuation of the comics industry’s previous longstanding practice of adding colour to black and white artwork during production — known as mechanical colour separation. When artists created full colour artwork, colour could be extracted from it to make separate printing plates, originally by photographing the art through three or four different colour filters, and later by scanning the art. Mainstream US comics only moved to the more expensive full colour art, and colour separation by extraction, in the 1980s (though Marvel’s Hulk magazine in 1978-1981 was a trailblazer). British and European comics had been doing it for decades (e.g. Eagle, TV Century 21, Asterix and TinTin).
Part 9a of my history looked at CMYK colour, the colour guides of Marvel, DC and other US comic books, their YRB / yellow-red-blue coding system, and the type of coloured dots seen on their pages from the mid-1950s onwards. Marvel changed to this type of dot — and the new acetate colour separation system that created it — in 1954, and DC in 1956, just in time for the so-called ‘Silver Age’ of comics. If you haven’t seen Part 9a yet, it might be worth looking back at it before reading this part.
In the late 1950s, the US comic book dots were often called ‘Ben Day dots‘ within the printing and publishing industry, even though the real Ben Day method had been largely phased out of comic books in the 1930s. When the painter Roy Lichtenstein shot to fame with his Pop Art paintings in the early 1960s, he informed the world that he was copying ‘Ben Day dots’ from the comics. No-one knows where he heard or read the name ‘Ben Day dots’, but it has continued to stick ever since, like ‘Kleenex’ for a tissue, or ‘Hoover’ for a vacuum cleaner. It is strongly associated with Lichtenstein’s paintings, but also with the comics which he copied — rather misleadingly, if we actually want to understand the new dot-making technology they used.
On the printed page, dots of the 25% tints like magenta / R2 below left, were ‘positive dots’, i.e. spots of actual ink. As seen in R3 (right) the darker 50% tints involved ‘holes’ in a grid of colour, dots created by the absence of ink — or what I call ‘negative dots‘. Printed on a white background, they were white dots, as the paper showed through the holes.
Printing ink was semi-transparent on the comic page, so when one ink was printed on top of another, the colour below showed through and a mixed colour was created. As seen in Hulk Green below, blue dots printed over yellow became dark green dots, and the overall effect was of a yellowish green. In Thing Orange (YR3; R3 over yellow) the negative dots of R3 became yellow, while the magenta grid assumed a scarlet hue.
This section continues with a demonstration of how the dots were actually made during the production of the comics. This has not been shown before in detail, with illustrations. Comic book production flies well below the radar of most histories of printing, and has also received little scholarly attention within the specialist comics literature. I have reconstructed the process from various sources, including material gathered for the Connecticut Historical Society’s 2003 exhibition celebrating the invention of the comic book. The CHS interviewed comics professionals including Dick Giordano and Will Eisner, as well as Mildred Marsh and Cynthia Blake, staffers who made colour separations at the Chemical Color Plate Corporation of Bridgeport, Connecticut in the 1950s and 1970s. Chemical Color created the printing plates for Marvel, DC, Archie, EC and other comic book publishers, and for Sunday newspaper strips.
My rediscovery of the process has not been without error and the need for correction. I believe the following material is accurate. I welcome feedback, added information and further correction.
Where 2 tints of the same colour are contiguous, they are continuous
A final point about these comic book tints before I attempt an explanation of how they were made. Given the nature of old-school comic book art, where one tint meets another there is generally a black outline between them — as seen in the detail from Strange Tales 110 below.
Occasionally tints meet directly, including different tints of the same colour, as seen in two of these details from Fantastic Four 89.
At these junctures an interesting phenomenon can be seen. When for example B2 meets B3, or R2 meets R3, the positive dots of the light tint are always perfectly positioned to meet the negative dots of the darker tint — in fact the positive dots merge into the grid structure between the negative dots.
Likewise, the spaces between the positive dots merge exactly with the negative dots in the grid. They are not just lined up at the same screen angle, which we would expect, but perfectly positioned as continuous rows of dots and grid lines.
This is shown more clearly below, in two examples from 1960s DC comics.
In the previous system, Craftint Multicolor (as seen in Part 9a) the lines and dots were always perfectly lined up like this, because they were printed that way on the Craftint boards. Any credible explanation of exactly how the acetate method created its dots has to explain how this phenomenon continued to occur in the new system. It may not seem particularly tricky, but I believe it is. I will return to this point below.
How the ‘Silver Age’ method was done
As in previous posts, I will work through a notional example of colour separation using just one panel. The colour separator would have worked on a whole page at a time. This way is unrealistic, but easier for me to create and, I hope, for you to take in.
Below is an out-of-copyright comic book panel from Magazine Enterprises’ Dream Book of Romance 5, 1953, drawn by Frank Bolle. For the actual comic book it was colour-separated using the ‘Golden Age’ Craftint Multicolor system — you can see the characteristic lines of Craftint. It was one of those ‘non-realistically’ coloured panels that romance comics did from time to time (a way of expressing strong emotion, perhaps). This scan is taken from the Digital Comic Museum web site.
I downloaded the original B&W art from Lars Teglbjaerg’s page at Comic Art Fans and I’m using it with his kind permission. I chose the image as a nod to Roy Lichtenstein’s romance comic paintings. I’m going to simulate colour separating it using the acetate method, but choosing different colours.
As discussed in Part 9a, the first step in the acetate method was a colourist making a sketchy colour guide, with more or less thorough YRB notations. The colour guide was done on a copy of the artwork, the same size as the printed comic page — a photocopy in later years, a ‘silver print’ earlier.
My own version below is completely different from the original colouring of Bolle’s panel, and intended to show a wide range of tints and colour combinations.
As a further tribute to DC romance books, I’ve adopted a convention sometimes seen on DC covers — Julie has R2 skin with only magenta (red) dots, while her male lover is Y2R2 — using both magenta and yellow dots. Inside DC comics, every white person was R2-only until 1969, when artist Neal Adams got them to start using the yellow tints Y2 and Y3 for the first time in decades. White skin in Atlas and Marvel books was always Y2R2, so my choice here also points up that difference between the two publishers.
The black-and-white artwork and the colour guide were both sent to the engraving company — our friends at The Chemical Color Plate Corporation of Connecticut.
The original artwork — i.e. the black-and-white page, not the colour guide — went to one part of the Chemical Color building, where it was photographed in a huge specialised camera. As with all old-school analogue photography, the result was a negative image — as shown below for my single panel. The negative was not actually B&W but opaque black on clear plastic film, i.e. black and see-through. The negative was used to photoengrave the black printing plate for that page.
Colour separation in detail
The colourist’s original colour guide went to another room where the colour separations were made. Here the colour separator — let’s call her Mildred, in honour of Ms Marsh — worked directly over this colour guide. (This detail fell into place only after I read Elliot R. Brown’s post, as mentioned earlier.)
For each page of artwork, and for each tint of yellow, red and blue, Mildred carried out a separate task, laying a separate transparent acetate sheet down on top of the colour guide for that page, and painting on it — one sheet at a time. If the job called for the full gamut of colours, that meant nine separate pieces of work, on nine acetate sheets.
Here was manual or ‘mechanical’ colour separation in action. It was clearly a collaborative process between the colourist and the colour separator. The colourist decided (with more or less instruction from editor, writer, artist or simply from past practice) which of 64 (maximum) defined colours was required on each and every part of the page, and produced a diagram / plan which informed the next steps in the process. Every one of those colour decisions was implicitly or explicitly stated, visually and/or by a written label. The separator’s task was to interpret the diagram and follow the plan, converting all those decisions into a material form — painted acetate sheets — which, as we will see, would go on to determine where the defined solid colours and dot tints would appear on three colour printing plates.
Each time Mildred painted an ‘acetate’, both the paper colour guide and the acetate sheet were held firmly in place by a pair of pegs at the top of the page. Since this thin plastic sheet was close to invisible, but vital to the technique, I can neither illustrate it nor ignore it. I therefore represent it here by partly fading out the image beneath it, and with the yellow word ‘acetate’. (In later pictures, please simply assume that the acetate sheet is there, because the text would only get in the way if I left it :0)
Mildred painted on each acetate in turn where a particular tint was needed. We don’t know what order she worked in, so let’s say she started with the acetate for magenta 25%, the R2 tint. She looked for all those parts of the colour guide labelled with, or known to require, R2. If the colourist did not label every part of the guide, the separator had to rely partly on what was shown on previous pages, or on her own knowledge of the colours routinely used in that comic, or by that publisher. (See for example the page from Thor 163 in Part 9a). A good example is the caucasian skin colour mentioned above, often routinely assumed to be Y2R2 or R2, depending on publisher, so not labelled on the colour guide.
On my imagined example I have labelled every colour.
The R2 areas Mildred needed to paint included all the mixed colours of which R2 was a part: R2B2 (the wall), Y2R2 (the man’s skin), the orange YR2 shading on Julie’s hair, and the dark blue jacket, R2B. The YRB notation made finding these areas relatively simple.
Below is the result of this first step in Mildred’s work. The R2 areas have been painted on the acetate with a dark red paint.
Mildred’s interview transcript states: “…you painted solid colors used red paint, […] a paint that would stay on the solid acetate.” What she might have actually said was that this paint would “stay solid on the acetate”. At a later stage in the process, as we’ll see, it was important that the red areas were ‘solid,’ with no gaps — and that they were were opaque, letting no light through. (Later she mentions a different technique using black paint, giving no details.)
I believe that she routinely painted with a brownish red liquid called Opaque Red. Eliot’s blog confirms that Opaque Red, or something very like it, was still used for this purpose at Chemical Color in the mid-1980s. This liquid had long been used in photography and photoengraving for touching up and correcting negatives, i.e. it was formulated for painting on a smooth plastic sheet. And, importantly, it was just as ‘solid’ and opaque as the black parts of the negative itself.
Here is a jar of the stuff, still being used on photographic negatives by Craig Sheaks, who posted this photo at The Darkroom on Facebook:
It was, as we will see, adapted very well to the acetate colour separation technique. Perhaps this technique was in fact developed partly because Opaque Red was already there, ready to do the job.
Later, starting in the 1960s, a sticky-backed plastic sheet called Rubylith — stuck onto the acetate and cut to shape with a scalpel — began to replace this kind of paint throughout the graphics industries, including comics. As mentioned, Chemical Color was still using Opaque Red or a similar liquid formulation in the mid-1980s. Many published accounts of colour separation in comics mention cutting Rubylith (or the similar orange Amberlith); the 80s and post-80s generation of colourists and production people have been interviewed and have posted about their work, and that’s what they knew and used. Cutting the sheets was still a laborious job, but more precise. Rubylith users in the comics biz sometimes look back on the Chemical Color era (and Opaque Red) with a certain amount of disdain.
Back in the day, let’s take a closer look as (imaginary) Mildred painted her acetate sheet for R2. The job wasn’t as simple as it might seem — working at comic book size, she was painting at a fairly small scale, and had to work fast.
Her finished R2 sheet, still in place on the colour guide, looked something like this:
All the R2 areas had merged into one — the black outlines which divided up the picture into its constituent parts had been covered up. However, Mildred had a way of adding the black outlines back, to help her check that her painting was correct. This was the final detail added by Eliot Brown‘s account.
There was another clear acetate sheet, printed with the black artwork, held on the same pegs as the colour guide and the acetate, and ready to flip down over the painted acetate. As Eliot says, the painted layer was like the filling in a sandwich, with the colour guide as the bottom slice of bread, and the acetate with the black artwork as the top slice. Looking down at the whole ‘sandwich’ at this stage, Mildred would have seen this:
And of course she could also have flipped down the top sheet at any earlier stage if she’d wanted to check as she went along (once her paint was dry, presumably). Flipping up the painted sheet she could also check her work back against the colour guide beneath if she needed to. The pegs kept the sheets lined up with each other.
And just to be clear, in real life she would be working on a whole page at a time, not the single panel which I am showing here.
Once this stage was completed, the painted R2 acetate — taken out of the ‘sandwich’ and viewed on a white surface — would have looked something like this :
Like the colour guide, this was not intended to be a fine or attractively finished piece of work. It was a functional object, part of the industrial production line of a cheap and disposable product. (Real) Mildred’s interview states that the acetates were washed clean for re-use after a job had been completed. It would be astonishing if any worked examples have survived; certainly I have never seen one. You are probably seeing one here for the first time — or at least, the best simulation I can give you. PLMK if I’m wrong.
(Update July 30th, 2021: Jeff Robertson has made a mock-up of a similar acetate (for a whole page) in his new blog post here.)
Let’s assume that imaginary Mildred painted the 50% magenta R3 area on her next acetate sheet. In this case it was a simpler, faster job, involving only lover-boy’s brown hair (YR3B3) .
In the final magenta phase, imaginary Mildred looked for all the solid red areas, marked R or YR, and painted those on her third acetate sheet. These were only small, but obviously a bit fiddly. Real interviewed Mildred told us she didn’t like intricate details. They slowed her down and cost her money!
Mildred now had three acetate sheets ready for the next stage of the process, looking something like this:
In order to produce the magenta printing plate, by photoengraving (just like the black plate from the original artwork), I believe that these three images must have been combined into one negative in a camera set up specifically for this purpose. I can’t give a full account of this part of the process, as I have found no details which I can pass on.
The 2003 Connecticut Historical Society interviews don’t clear up the mystery. In an interview reduced to precis form, engraver Dan Jocis told the CHS: “Shooter used to make dot pattern for color percentages” — and nothing more. A ‘shooter’ must have been a camera operator. Dan himself, unfortunately for us, “Did every part of engraving work except camera work.” Also, we can speculate that he might have given more details which the person writing the precis didn’t fully understand, so summarized in this way. No camera operator was apparently interviewed by the CHS.
I believe that this extract from Stone and Eckstein’s book Preparing art for printing, 1965 (a book I cited in Part 9a) while not specifically referring to comics production, holds the key to understanding this procedure:
“This original Benday process is virtually obsolete and is being replaced by an in-the-camera screening method which is more efficient, less costly and easily manipulated by the cameraman. […] Today tinting is accomplished with a screen similar to the halftone screen. It is placed in the camera in front of the film and a white or black surface is photographed. The screen value, 10%, 20% , 30% , etc., is controlled by manipulation of the exposure.” (p.45) [My emphases.]
‘The screen value’ is another way of referring to the ‘tint value’ or the strength (darkness) of the dot tint.
They illustrated that paragraph with this picture of ‘line copy’ — i.e. black and white artwork — and its tinted version:
In Chemical Color’s camera, the ‘surface’ which was photographed was in each case one of Mildred’s acetate sheets with its painted-on red shapes. Opaque Red was designed to fill small ‘holes’ in a ‘B&W’ negative, just as if it had been black; it could also be photographed in B&W just like black — just as blue pencil or blue wash could be photographed as white. Thus each Opaque Red-painted acetate was the equivalent of ‘a black surface,’ effectively a piece of ‘line copy’ just like the black fishy image above. Just like the fish, it was ready to be ‘shot’ as an area of dotted tint; 25% ‘screen value’ in the case of the R2 acetate below.
The acetate for solid colour could be ‘shot’ unscreened. Then the same 60 lines-per-inch screen could be used to shoot areas of 25% and 50% tint from the other two acetates, one shot after the other, controlling the tint value by varying the exposure of the shots. The same screen, I believe, must have been left in place in the camera between these two shots. ‘A screen similar to the halftone screen’ to the best of my understanding must have been a contact halftone screen. And the same piece of film was also in the camera throughout all three shots, producing a combined single negative at the end of the process.
This is a credible explanation for the consistent precisely continuous positioning of the adjacent tint patterns which I noted above; the screen didn’t move between shooting the 25 and 50% tints. It stayed in exactly the same position. So the two sets of dots which ended up on the single screened negative lined up perfectly, as I showed above on printed examples. Every time!
Some printing experts have suggested to me that two different screens would be necessary, and obviously would have to be very precisely lined up every time a shot was taken. I believe (a) that this would not have happened in the world of fast cheap comics production, and (b) even if it could be done, slight errors in positioning would surely have crept in — errors which we just don’t see on the printed page. Only the double use of a single fixed screen fits the bill.
It also implies that slight variations in exposure time or other photographic factors might create tints of variable dot size (value) or appearance in the camera — not only during printing as previously mentioned — i.e. variations in the size of the 25% dots, and in the checkerboard or grid of the 50% tint, can also be partially accounted for at this stage of production.
Whether or not I am entirely right about the method, the end result must have been a negative which looked something like this (but with complete continuity across tint edges, unlike my primitive effort) — reversed both in B&W and right-left terms:
When this imaginary negative was etched (photoengraved) onto a printing plate, it would, if used to print a magenta image, create something like this (which in reality would never be printed on its own, but only as part of a four-colour print job):
If this looks like a hot mess — did imaginary Mildred screw up? Surely not! — here is another notional image, with the black artwork added in, representing ‘black printed on top of the magenta’:
Compared to tint-making in modern software on a PC or Mac, this acetate method may seem like madness. Perhaps now the method behind the madness is starting to come into focus…?
Back at the imaginary separator’s work-bench, Mildred now had to do the same work twice more — making the blue and yellow images. Let’s say she next painted the three acetates for the cyan printing plate, one each for 25% B2, 50% B3 and solid B:
The resulting image, if ever printed on its own, would look like this:
Finally for my simulated panel — which, unlike DC comics before 1969, contained a yellow tint, Y2 — Mildred only had to make two acetates for 25% Y2 and solid Y. For a real old-school DC book she would only have needed one, for the solid Y; for a Marvel book, generally one for Y2 as well, if only for the flesh tint. Y3 came and went at Marvel over the years.
The resulting image for my panel would look like this:
I didn’t put an outline around this yellow image because I’m now imagining it not as a standalone notional image, but as the first image ‘actually’ to be ‘printed‘, combining the colours as my panel goes through the hypothetical printing press. This ‘printed’ image will end up with its own black outlines.
After yellow the magenta image is printed, and the result is this:
Last of the YRB colour plates is the cyan/blue, giving us this image, now with clearly visible rosettes as blue tints overlie the red ones at a different ‘screen angle’:
Still something of a mess, you might think, until the black ‘key’ plate is printed over the rest to pull it all together:
To add a touch of realism, here is my final result as you probably would have seen it in a Silver Age comic… with the colours slightly misaligned or ‘off register’ :0)
The colours seen above are obviously far too bright and uniform to represent an old-school comic book panel accurately. My image-making skills are rudimentary. I am therefore very grateful to artist Nicholas Burns, who has donated this newsprint-ised version… kudos and a zillion thanks!
I hope that Nicholas’s version of ‘my’ panel convinces you that this seemingly crazy colour separation technology really was the way it was done in all those Silver and Bronze Age Marvel, DC and most other US comics.
Not only that, but — laborious and time-consuming as it was — it remained cheaper than the alternatives (based on colour extraction from full-colour artwork) which many other periodicals used. This was vital in an industry which struggled to keep its products ‘all in color for a dime’ as long as it possibly could.
That price went up and up through the 1960s, 70s and 80s, until the struggle was abandoned, offset litho printing and better paper were brought in to replace letterpress on newsprint (along with Rubylith and Amberlith to replace Opaque Red), and in the 90s computer colouring took over, step by step.
That, however, is a whole nother story.
This concludes Part 9 of my History of ‘Ben Day dots’ — many of which, as you now know, weren’t really Ben Day dots at all. As I said before, please send comments and corrections. I’m trying to break new ground with this attempt at a thorough history of the topic. I may have got some things wrong, or made some things less than clear.
I’m not committing myself to a Part 10 at this point. Coming full circle to where I started, with the 1960s and the type of comics — and of course dots! — that Roy Lichtenstein copied, seems enough for now. I hope you’ve enjoyed discovering this stuff alongside me.
The end; кінець; fin; fim; ende; fine; סוף; slut; einde; koniec; النهاية; 終わり… et cetera.
Once again, thanks are due to Mildred Marsh, Cynthia Blake and all their colleagues at the Chemical Color Plate Corporation, and to Andrea Rapacz at the Connecticut Historical Society for sending me the the texts from their exhibition; to Lars Teglbjaerg for the Frank Bolle romance panel; to Dewey Cassell for the Batman page; to Craig Sheaks for the Opaque Red photo; to Craig Yoe for explaining how widespread the ‘grey paint’ method probably was — the alternative comics colour separation method (more research needed!); to Nicholas Burns for many things, and to Pascal Lise for a stimulating discussion about 50% tints. Also to Todd Klein, Anthony Tollin, José Villarrubia and Bob Rozakis for writing about comics colouring online — look for their stuff!
Also to Jeff Robertson, who alerted me to Eliot R. Brown‘s amazing account of his visit to Chemical Color in the mid-1980s, when the acetate method was still going strong.
If you haven’t already, you should also see Jeff’s own excellent post about pre-digital colour in the comics. You’ll find stuff there that you won’t find here!
I believe I am also indebted to Khouri Giordano, who I think authored a web page some years ago which I now can’t find. IIRC he gave some details about the acetate system which I found hard to believe (9 acetates for every page?!?) but which set me on the trail to confirm the facts.
Last but definitely not least, Fiona McIntosh provided research assistance, tech advice, and incalculable, invaluable support besides.
Main content © Guy Lawley 2021
The Hulk, the Fantastic Four (including the Thing) and Dr Strange are copyright © Marvel Characters, Inc..
Artwork from Blackhawk and Justice League of America is copyright © DC Comics.
Is there a complete library of hi-res Ben Day patterns anywhere? Alternatively, what book or other physical resource would list all the patterns?
SUCH a good question, and alas, there is no such resource… at least not one known to me. It appears that Ben Day ‘specimen sheets’ and/or catalogues were looked on as working tools (as were the screens themselves, and the Ben Day ‘machines’) and generally not kept or collected.
Also, what little material has survived may be difficult to date accurately.
I have a catalogue in ‘loose leaf’ form; the pages have punched holes in them and are held together with string. There are different copyright dates on different pages (from memory, possibly 1911 and 1936). I suspect the idea was that new pages were added as years went by and out-of-date pages discarded — as Day’s range of patterns changed with time.
My catalogue is only a possibly flawed snapshot of a part or whole of the range at an unknown date!
Are you only interested in the actual product of the Ben Day company? After his patents ran out a number of companies copied his tech in the US, Britain and Germany, maybe elsewhere (early C20th, maybe before) and ‘mechanical tints’ under various brand names might have used the same or slightly variant patterns.
May I also ask, are you researching the Day tints or hoping to make use of them in some practical way? Or both?
Happy to correspond further by email if you like.