HELP: What kind of film is used in making color separations (and who sells it?)??

[stormbytes]

I'm looking to mess around with transparencies (b/w) using color separation film. I know the stuff is aka "Graphic Arts Film" but I can't seem to find exactly what it is or who carries it. Any help on the issue would be much appreciated!

 

[Neanderman]

I'm looking to mess around with transparencies (b/w) using color separation film.

Continuous tone or halftone screened?

 

[Photo Engineer]

You can use Tri X sheet film for this.

PE

 

[removed account4]

a guy on eboo sells rolls of plus x aerial film
that he suggests can be used for color separations.
his user name is mrfoto1. i have bought from him before
he is a really nice guy, and if you ask him questions he will
be happy to answer them.

you might also find what you are looking for through one of apug's sponsors
- photowarehouse ( ultrafine ) ... they sell all sorts of stuff ...

goodluck!

john

 

[Mick Fagan]

Lith film that the graphic arts houses use(d) is a bit different to something like TRI-X. Although TRI-X can be used quite succesfully, it is quite thick and unbendable when compared to almost every kind of Litho film I have ever seen and/or used.

I currently have some Ilford Anitec "Newsdot Matte projection film" as it is called.

I bought this about 10 years ago before I converted to LASER engraving and deleted litho film from my processing.

The film box tells me that it is 30.5 x 45.7cm x 100 sheets on a .10mm Polyester Base. The catalogue number is 171-0203. I'm not saying that this film is still manufactured, but this should at least give you an idea of what is/was around.

DuPont was a very, very big manufacturer of this kind of product, as was Kodak and Agfa Compugraphic, Ilford was a bit player by comparison.

Mick.

 

[rmolson]

film for color serparations

Film for color separation


I was a graphic arts color camera man 40 years ago when we made separations by hand and developed in trays. Both transparencies and reflection art required an unsharp premask. For transparencies it was to reduce contrast and increase the illusion of sharpness in addition to correcting colors and printing ink deficiencies. Masking film was of a fairly low contrast and processed in conventional developers likeDK-50
An early separation film used was Super XX then a ASA 100 speed film with a strong straight line also processed inDK-50. The necessary curve shape being adjusted in the masking stage. by exposure and development. Filters used for separation where 25A red, 58 Green and 47B blue.Filters for masking varied some what depending on needed color correction. Later specific films were developed for transparencies and reflection copy. Reflection copy required a higher contrast film to compensate for the maskings contrast reduction. I would imagine that today FP-4 would be suitable for separation and even masking using a very dilute developer.
The process was also well describe in Kodak publications for dye transfer printing, if you can find any in library archives.

 

[stormbytes]

Continuous tone or halftone screened?

I don't really know the difference. Care to educate?

 

[stormbytes]

You can use Tri X sheet film for this.

PE

Ron -

OMG... That'd cost a million Bucks!

 

[stormbytes]

DuPont was a very, very big manufacturer of this kind of product, as was Kodak and Agfa Compugraphic, Ilford was a bit player by comparison.

Mick.

I don't suppose you'd know what films are used for this process nowadays and where they'd be sold/available?

I got a tip on this thread for UltraFine. I looked them up and they seem to have quite a variety available. Though I have no idea what I'm looking for. I'm guessing I'll have to call'em up.

What I'd like to do is make b/w positive transparencies (large) from 35mm & 6x6 negatives.

 

[stormbytes]

you might also find what you are looking for through one of apug's sponsors
- photowarehouse ( ultrafine ) ... they sell all sorts of stuff ...

john

I think this stuff may be it. I'm going to give them a call sometime tomorrow. It's kind of hard when I don't entirely know what I'm looking for. What I do know is that I'm trying to make large (display) positives (slides) from 35mm & 6x6 negatives. The idea I had is the sandwich the positives between 2 sheets of newton-free glass, and hang it in front of (or in line with) a window.

Thanks for the tip! Any more info would surely be appreciated.

 

[gordrob]

Your best bet for film to get color separations from slides is to use TMAX 100 developed in either TMAX RS or HC110. I don't know what you would print the separations to in the way of a film to get e B&W transparency though.

Regards
Gord

 

[David H. Bebbington]

There seems to be a lot of confusion here! Iserious, are your originals negatives or positives (transparencies)? Color or b+w? Either way, the last thing you want to do is make separation negatives, which is when you copy a (positive) color original onto 3 sheets of b+w film (panchromatic film, sensitive to all colors), one each for red, blue and green, so that you can print the picture photomechanically with separate passes for red, green and blue (and probably another one for black). You may well make these negatives through a dot screen, in which case they are called "half tones".

Assuming you have black and white negatives, what you need is black and white film, either blue sensitive ("ordinary") or blue/green sensitive (orthochromatic film), which you can make positives on in the same way as printing paper. Your cheapest option would be to find surplus rolls of "process" film (like "Kodalith") which was designed to give very high contrast but which can be persuaded to reproduce continuous tones if given enough additional exposure and developed in a moderately high-contrast developer such as Ilford Phenisol or even PQ Universal. This will take a little experimentation but you should find rolls of Kodalith up to 60" wide. If your orginals are color negatives, the same principle applies but you will need panchromatic film (senstive to all colors). If your orginals are color transparencies, you will need to make an internegative (with an enlarger, with a sheet of film instead of paper).

Let us know what your orginals are and we can take it from there.

Regards,

David

PS: For b+w positives, this is the film you need:
http://www.freestylephoto.biz/sc_main.php?resultpage=1&cat_id=2001&sp=
Second-hand would of course be cheaper, but there doesn't seem to be any around!

 

[stormbytes]

Let us know what your orginals are and we can take it from there.

Regards,

David

David,

First off, thank you so much for the detailed response. I agree, it seems I've been rather stingy on the details of my undertaking which has led to some confusion. Allow me to make amends!

What I am trying to accomplish is this: I would like to enlarge a simple b/w negative (tri-x/t-max/whatever) onto "film" instead of paper. The result would be a positive transparency (also b/w) that would be subsequently sandwiched between two sheets of newton-free glass, and strung with fishing wire in front of a light source (window, etc).

I thought it would be an interesting (and out of the ordinary) to try this out. I have a friend who used to do professional photography years and years ago. He told me the best thing to use (considering cost of materials & available sizes) would be the "same stuff used in making color separations". Hence the reference. I however have no intention of working with color.

I am reluctant to use traditional (camera) film as 1) it costs an arm and a leg! 2) it's only available in fixed sizes, 3) it's sensitive to all spectrums of light (can't be used in a safelight environment) and 4) it's far too sensitive (I'd be looking at an iso of 4-12 or thereabouts).

I was told to use "graphic arts" film, and I've thus far been searching for what exactly that is!?

So far... I have one solid lead (though again, this is just a hunch as I really have no clue what it is I'm looking for!).

This is an excerpt taken directly from the product description page at ultrafineonline.com

"Ultrafine Continuous Tone Duplicating Film:

Make duplicate B & W negatives or slides. Enlarge or contact. Blue Tint .007 mil polyester base. Slow speed ( ISO 4) Standard development in either photo paper developer or Graphic Arts Rapid Access. Yields direct positive image. Red or Yellow safelight."

Any thoughts and suggestions would be much appreciated.

 

[David H. Bebbington]

undertaking which has led to some

"Ultrafine Continuous Tone Duplicating Film:

Make duplicate B & W negatives or slides. Enlarge or contact. Blue Tint .007 mil polyester base. Slow speed ( ISO 4) Standard development in either photo paper developer or Graphic Arts Rapid Access. Yields direct positive image. Red or Yellow safelight."

Any thoughts and suggestions would be much appreciated.

This is NEARLY right except that it's direct positive film. This would be used if (say) you wanted to make an 11x14" contact print from an image on a 35 mm negative. With this film, you could make an enlarged 11x14" copy negative from your 35 mm negative and then print this big negative onto paper and get a positive. What you need, however, is negative film which will make a positive from your negative. You are right, regular camera film would be too costly, probably not big enough, hard to handle (because it's sensitive to light of all colors) and also not contrasty enough. The freestyle listing shows the right kind of material, it may of course be possible to buy the same stuff cheaper elsewhere.

Regards,

David

 

[stormbytes]

You are right, regular camera film would be too costly, probably not big enough, hard to handle (because it's sensitive to light of all colors) and also not contrasty enough. The freestyle listing shows the right kind of material, it may of course be possible to buy the same stuff cheaper elsewhere.

David,

Well I'm glad to be on the right track. I think I'll throw the dice and pick up a small pack of this Freestyle film. I'd like to play with it and see what happens. As for the contrast issue, it's actually very interesting that you mentioned that. The Freestyle film has a practically vertical curve! I was thinking I'd have to tweak the contrast OUT of it! But then again, I don't know how going from one generation to another affects contrast. So I'm glad you pointed it out.

 

[Neal]

Dear Daniel,

You may want to consider coating a sheet of glass with liquid emulsion, or using one of the RA-4 clear display materials. I would start with the liquid emulsion as I'm just plain cheap.

Neal Wydra

 

[rtuttle]

I looked up on Agfa's website, they don't seem to make the pan film used for color seperations any more. That's where we used to get ours. You could use Tri-X or any pan film for that matter but it's really fast so control is going to be hard until you get used to it. But it is certainly going to work for you. 4/c seps on a camera are quite a pain, we had a 26x32" horizontal camera we used for that and it took about half the day to get one going right. All things considered I miss the analog work flow, sure it took 5x longer but there was a better feeling of accomplishment when the job was done.

 

[smieglitz]

You might also try Ilford Ortho Plus sheet film. It is readily available in 4x5 and 8x10 sizes and perhaps other sizes (when Ilford does their yearly run of ULF films). It is essentially FP4 but with orthochromatic response rather than panchromatic so it can be developed under a safelight.

Another option might be Freestyle's premium APH orthochromatic halftone film. It is available in a large variety of sizes and will give results varying from extremly high contrast posterized results with standard AB litho developers to continuous tone results with extremely diluted paper developers (e.g., Dektol 1+20). Check this link also for info on Dave Soemarko's LC-1 developer formula for contone results with the APH film:

http://members.aol.com/fotodave/Articles/LC-1.html

 

[richard ide]

Hi Daniel,
Check out item #7617421028 from mrfoto. 24" x 30". Not sure if it is neg/pos or neg/neg but cannot beat the price. I don't think you want a film with a near vertical curve as it is very high contrast. High contrast films I used in the past were capable of giving a 5+ density over a one stop range. If you would like more info - pm me.
As an after thought, you would have to make a negative from a transparency first on pan film to enlarge from and possibly an unsharp mask for contrast control

Richard

 

[Donald Miller]

If you are wanting to take a camera negative to an enlarged positive, then I would suggest that you look into APHS film. This film is a halftone film that I have used for masking and also for making enlarged negatives (requires an intermediary step beyond what you want to do). I believe that both Freestyle and Photowarehouse handle this material. The mfg that I have is Arista.

This can be used in color separations with an AB developer after exposure through sharp cutting filters. It can also be used as a continuous tone material by using less active developers. I have used dektol in dilutions that range from 1-30 for unsharp masks to 1-10 for continuous tone negatives of normal density.

Some people even use this for camera film (see Jim Galli's Rodinal formulation). It is low speed (typically ISO 3-6) which lends itself to enlarging in your application. The price is right and I believe that it is available in sizes up to and includiing 20X24. Good luck.

 

[Michel Hardy-Vallée]

David,

Well I'm glad to be on the right track. I think I'll throw the dice and pick up a small pack of this Freestyle film. I'd like to play with it and see what happens. As for the contrast issue, it's actually very interesting that you mentioned that. The Freestyle film has a practically vertical curve! I was thinking I'd have to tweak the contrast OUT of it! But then again, I don't know how going from one generation to another affects contrast. So I'm glad you pointed it out.

The basic formula is Final contrast = contrast1 x contrast2. Let's say you use the gamma measurements. Your target gamma for a positive transparency image is 1.5; a normal negative for paper printing has a gamma around 0.6. You thus need a positive film that can achieve a gamma of 2.5 (1.5/0.6=2.5), so ortho films are in the right ballpark. If you can find a spec sheet for the film you're using, look at the time-gamma curve. It will give you a good starting time for development.

I've done transparencies with 35mm contact-printed on movie print film developed in print developer, and it works pretty well. Your process is more or less the same, but with a larger target size.

 

[removed account4]

hi daniel

mrfoto1 knows quite a bit about color separation negatives.
might be worth just asking if his film works for that and
"picking his brain".

the film you fell into at photowarehouse is for duping (single step) film.
it is VERY slow ( like azo + floodlight ) and will not like to be enlarged upon.
it also gives a blue hue that might be distracting if you want to display it.


good luck!

-john

 

[stormbytes]

You may want to consider coating a sheet of glass with liquid emulsion, or using one of the RA-4 clear display materials. I would start with the liquid emulsion as I'm just plain cheap.

Either you're a genius or I'm a complete moron (i'm betting on the latter). That's a GREAT idea! I even have a bottle of Liquid Light that I picked up from Rockland a few months back.

Liquid Light would work I take it? (coated on glass)

I'd ask for coating tips but I take it it's probably covered in MANY other threads

Keep the amazing tips coming! I will be sure to post results as soon as I actually get off my rear and do this

 

[stormbytes]

Another option might be Freestyle's premium APH orthochromatic halftone film. It is available in a large variety of sizes and will give results varying from extremly high contrast posterized results with standard AB litho developers to continuous tone results with extremely diluted paper developers (e.g., Dektol 1+20). Check this link also for info on Dave Soemarko's LC-1 developer formula for contone results with the APH film:

http://members.aol.com/fotodave/Articles/LC-1.html

I've actually pretty much decided on trying Freestyle's stuff. The contrast control was on my mind the moment I saw the practically-vertical curve they post in their specs pdf. I will give the link a look-see and undoubtedly have fun playing with the stuff!

 

[stormbytes]

Check out item #7617421028 from mrfoto. 24" x 30". Not sure if it is neg/pos or neg/neg but cannot beat the price. I don't think you want a film with a near vertical curve as it is very high contrast.

As an after thought, you would have to make a negative from a transparency first on pan film to enlarge from and possibly an unsharp mask for contrast control

Richard

Richard,

I emailed the seller and will certainly consider this film. Apparently he's got two different types (if I understood his description correctly - his auction format is a bit distracting i find, anyhow...) The cost of shipping is, at least by my standards, prohibitively expensive. But the guy's in PA and I'm presently in NYC. I'm hoping local pickup will be an option. As for the high contrast (the Freestyle stuff), I'm told there are developers out there specifically designed to yield continuous tone. I think I'm going to dabble in quite a bit of this stuff - different films, developers and even hand-coating glass as someone on this thread suggested earlier.

It's a lot of fun to stray from the norm (the norm being paper). I've also had nothing but intrigue from people with whom I've shared this idea of presenting transprencies (vs. traditional paper prints) as a final product.

I can't thank you enough for your contributions. Trekking in the unchartered (relatively speaking of course) is always a throw of the dice, but I gotta admit - It's fun!