Color Paper Top Emulson Layer

[RedSun]

No, no, you completely misunderstood what I was originally asking. Same with most of the people, even PE. This is funny.

I was printing test strips, from 18% grey negative, for calibration. The strips are 1" wide, 5" long. I exposed 1/2 of the strip and left the other 1/2 un-exposed in order to get white base for comparison.

I've done this many times and I never had problem with it. But this time, the white un-exposed 1/2 strips came out light blue. The blue color is darker near the thin edges where the strips attached to the Jobo test drums. When I washed the test strips in tap water, I could see that some of the blue color can be rubbed off with hands and running water. So clearly the strips are not washed well.

The un-exposed paper never received light, no safelight, as PE suspected. The blue color is the coating, not actual image dye.

Here I'm doing an experiment. I cut a strip of Fuji Super C paper. This paper has never seen chemical. Then I put the paper under faucet with drops of water. Here you can see clearly that the blue color was washed off (or washed away) by the running water. There is nothing to do with the chemicals.

With all this, it is clearly that I should not have skipped the final rinse stage. The original blue coating was not 100% washed away.

I know this whole thing made a fool of some body, or some people. But common sense prevails. The problem with APUG is that, people always want to teach a fool, not realizing that who the fool is

Sry no flame here. I just do not understand why folks made it too complicated.

Thx for the help anyway.

 

[frotog]

That was what I read regarding the Fuji CA paper. I just do not remember the terminology and the source of it. The blue coating does not do much, if I remember it correctly.

Well, whenever you say anything different, there would be many people trying to TEACH you. That is what I've learnt so far at APUG. I just need to learn how to ignore it....

Yeah, that's right...ignore it. You're clearly better off not knowing.

 

[AgX]

Sry no flame here. I just do not understand why folks made it too complicated.

Lurking at this thread from the beginning, it's kind of looking at two worlds apart...



(Can't think of a fine way to bridge them as seemingly I'm founded in that Rochester guys' thinking too.)

 

[wogster]

No, no, you completely misunderstood what I was originally asking. Same with most of the people, even PE. This is funny.

I was printing test strips, from 18% grey negative, for calibration. The strips are 1" wide, 5" long. I exposed 1/2 of the strip and left the other 1/2 un-exposed in order to get white base for comparison.

I've done this many times and I never had problem with it. But this time, the white un-exposed 1/2 strips came out light blue. The blue color is darker near the thin edges where the strips attached to the Jobo test drums. When I washed the test strips in tap water, I could see that some of the blue color can be rubbed off with hands and running water. So clearly the strips are not washed well.

The un-exposed paper never received light, no safelight, as PE suspected. The blue color is the coating, not actual image dye.

Here I'm doing an experiment. I cut a strip of Fuji Super C paper. This paper has never seen chemical. Then I put the paper under faucet with drops of water. Here you can see clearly that the blue color was washed off (or washed away) by the running water. There is nothing to do with the chemicals.

With all this, it is clearly that I should not have skipped the final rinse stage. The original blue coating was not 100% washed away.

I know this whole thing made a fool of some body, or some people. But common sense prevails. The problem with APUG is that, people always want to teach a fool, not realizing that who the fool is

Sry no flame here. I just do not understand why folks made it too complicated.

Thx for the help anyway.

View attachment 61166

There is another possible reasoning for this, it's easy to make a powerful but cheap red laser, it's a little harder to make a powerful but cheap green laser, it's harder still to make a powerful but cheap blue laser, for example CD and DVD players use red lasers, a lot of true laser printers also use red lasers for exposure, even when dealing with other colours. Paper intended for machines like the Fuji Frontier might have a blue dye layer, simply to help out the blue lasers in the machines, to get a good exposure.

 

[RedSun]

This is what I was thinking. The other possibility is the compromise between traditional optical vs digital printing. Blue/cyan coating would make the exposure time longer.

I was thinking my blix chemical is bad. But it is not the case since this coating has nothing to do with developing.

All the Fuji CA papers I use have this blue/cyan color coating.

I'm not sure.

 

[Photo Engineer]

Well, I cannot explain the result you are getting Red Sun. Sorry.

If I assume that the scan you posted is properly processed in fresh chemistry, then I would say that the paper was defective.

If I assume what Paul says about lasers, I still have to assume that the blue dye washes out, as it is designed to do.

All of this leaves me without the ability to give you an answer. Sorry.

Now, to answer the OT post by RPC, well, you can get an answer by assuming that the paper is balanced so that the orange of the negative is "neutral" to it. In fact, paper is tungsten balanced + "negative orange" and then you still have to add about 50R to most enlargers to get a good print. This is all done to avoid your having to use cyan filtration. Using 3 colors (C/M/Y) is just too confusing.

Another way to look at it though is to say that the paper is designed to ignore the mask.

PE

 

[RedSun]

I think here we go circles. Her I'll try one time, trying to get it clear.

This is Fuji CA Super C color paper. Below is a piece of new paper.


I cut the same piece of the paper and put it under sink faucet. No chemical at all:


You can see clearly that the blue/cyan coating was washed away. This paper never sees chemicals.

I cut the same paper into strips and printed 1/2 of them with 18% grey negative. Below are two of them I printed:



The scanner did not do a very good job here. 1/2 of the strips were exposed and the 1/2 were not exposed. After processing, the 1/2 un-exposed strips should be white. The top strip is old and the white paper is white. But the newer (lower, 2nd) strip shows a light blue/cyan color. You probably can't tell from the scan, but I can see clearly with the actual strips. It is the same color tone with the original new paper. This is the same top blue/cyan coating that did not get washed away.

The paper is fine. No problem with it.

 

[Prof_Pixel]

You can see clearly that the blue/cyan coating was washed away. This paper never sees chemicals.

Sigh. It's all a matter of semantics: washed AWAY - yes, washed OFF, no. The dye is in one (or more) gel layers on the paper and is washed OUT of the gel layer(s), leaving the gel layer(s) behind.

 

[Photo Engineer]

If the scans are reasonably accurate in density, then please note the Dmax of the top strip and compare it to the Dmax of the bottom strip. The bottom strip is considerably more dense than the top strip indicating over development may be the problem.

Fuji did introduce CA type II papers in 2006, and they claim that the new papers develop more rapidly. They have supposedly released a new RA developer for this paper. IDK if this is the case, but I do think that the development (Dmax and Dmin) are different in the two strips.

Check time and temperature, and also check the contrast of the image you get.

PE

 

[RedSun]

If you run the second strip under the faucet, does the light cyan color go away? If so, does it come back when it is dried? I think you are making a connection between the color of the unprocessed paper and the cyan cast of the test strip where there isn't any. They are coincidental and unrelated.

I have been always talking about the blue/cyan top coating, as seen in the second picture. I think it is in the top protective layer.


For the unprocessed paper, I believe the color can be completely washed out in rinse water (as seen in the 2nd picture). For the white part of the test strip, I can wash out the blue/cyan color with rinse water and the cover won't come back.

I believe this color has nothing to do with the image forming dye....

This paper color is documented in Fuji's document, as the Raw Material Color of the paper.

 

[DREW WILEY]

I've never have a problem. The blue dye on the Fuji paper washes out completely for me during an
initial prerinse of less than a minute in the drum. This is distinct from the image-forming dyes which
remain behind after full processing. I don't know what it's function is. The difference between the latest Fuji papers which are digitally "optimized" and the previous Super C paper is only about 5cc's of G sensitivity. Anwyay, the previous paper also was blue in its unprocessed state. Current green
laser diodes are actually filtered, so relatively weak. True green diodes are coming on the market but
are relatively expensive. I'm skeptical that the blue color of fresh paper is related to this at all.
An interesting question, but I've totally ignored it because it has no impact whatsoever on my ordinary practical workflow.

 

[RedSun]

Yes, finally someone can speak with his/her own experience of using Fuji paper.

I had not had any problem with this until my last batch. The blue/cyan color messed up my color calibration. I do not know why this happened this time. I did cut another part of the roll paper, but I do not think it makes any difference with the same roll of paper. But at least I learnt not to skip the final rinse even with test strips.

I believe this blue/cyan color has something to do with optic/digital exposure.... Of course you get the added benefit of knowing where the emulsion side is.

 

[Photo Engineer]

Read my previous post and look at the scanned Dmax values of the old and new paper.

I've also explained the reason behind the blue color. It is there to adjust speed and to sharpen the image. It washes out. Nothing washes off! The blue color of processed paper that Red Sun is seeing is not related to the blue dye in the paper that washes out! It is probably fog of some sort.

If you fully process a sheet of unexposed paper, and just blix a sheet of unexposed paper, then if they differ in blue color (or cyan), then it is fog. If they do not differ in color, then it is indeed retained blue dye, and this indicates some sort of defect in the paper or process.

PE

 

[Prof_Pixel]

For the unprocessed paper, I believe the color can be completely washed out in rinse water

YES - That's what I have been saying

I believe this color has nothing to do with the image forming dye....

YES - Again, that's what I have been saying (But as PE has noted, it is possible that bad paper or processing chemicals might create fog that IS a result of the image dye forming couplers.)

 

[RedSun]

Read my previous post and look at the scanned Dmax values of the old and new paper.

I've also explained the reason behind the blue color. It is there to adjust speed and to sharpen the image. It washes out. Nothing washes off! The blue color of processed paper that Red Sun is seeing is not related to the blue dye in the paper that washes out! It is probably fog of some sort.

If you fully process a sheet of unexposed paper, and just blix a sheet of unexposed paper, then if they differ in blue color (or cyan), then it is fog. If they do not differ in color, then it is indeed retained blue dye, and this indicates some sort of defect in the paper or process.

PE

Well, well, well....

There is no paper fog at all. The paper has no defect.

The blue color of the processed paper can be washed off, washed away, or washed out, or whatever you want to say it. I tried some strips with 2 minutes RA rinse and the blue color did go away completely, as it supposed to be. The un-exposed 1/2 strips are white color, just as the previous batches.

It is just a simple blue/cyan top coating get washed away during pre-rinse. I do not understand why people made it so complicated....

 

[RedSun]

YES - That's what I have been saying

YES - Again, that's what I have been saying (But as PE has noted, it is possible that bad paper or processing chemicals might create fog that IS a result of the image dye forming couplers.)

This gets funny. Where is the fog? where is the paper defect? Can you just read what I said????

Thanks anyway. No need to repeat.... Thanks again.

 

[kevs]

No, no, you completely misunderstood what I was originally asking. Same with most of the people, even PE. This is funny.

I was printing test strips, from 18% grey negative, for calibration. The strips are 1" wide, 5" long. I exposed 1/2 of the strip and left the other 1/2 un-exposed in order to get white base for comparison.

I've done this many times and I never had problem with it. But this time, the white un-exposed 1/2 strips came out light blue. The blue color is darker near the thin edges where the strips attached to the Jobo test drums. When I washed the test strips in tap water, I could see that some of the blue color can be rubbed off with hands and running water. So clearly the strips are not washed well.

The un-exposed paper never received light, no safelight, as PE suspected. The blue color is the coating, not actual image dye.

Here I'm doing an experiment. I cut a strip of Fuji Super C paper. This paper has never seen chemical. Then I put the paper under faucet with drops of water. Here you can see clearly that the blue color was washed off (or washed away) by the running water. There is nothing to do with the chemicals.

With all this, it is clearly that I should not have skipped the final rinse stage. The original blue coating was not 100% washed away.

I know this whole thing made a fool of some body, or some people. But common sense prevails. The problem with APUG is that, people always want to teach a fool, not realizing that who the fool is

Sry no flame here. I just do not understand why folks made it too complicated.

Thx for the help anyway.

View attachment 61166

I see; though my prints were usually rubbish, I never saw anything like that when I used to make RA4 prints on Fuji papers. It's very strange. Sorry for my misinterpretation of your OP (note to self - engage brain before posting...). Thanks for posting the image, I hope you can solve your problem anyway.

Best,
kevs

 

[RedSun]

Well, I thought I could get away with saving 2 minutes with a test strip. That is about 1/2 of the total processing time. So apparently sometimes it does not work.

This is all the fun stuff with color printing, from color filter setting, density measure to test strips, drying the drums etc... This is also why not many folks still do RA-4 work....

 

[anikin]

Well, I thought I could get away with saving 2 minutes with a test strip. That is about 1/2 of the total processing time. So apparently sometimes it does not work.

RedSun,

I see what you were trying to do. It makes sense now. When I print color with Jobo, I don't process test strips in the drum. Instead I just dunk the strips straight into the beakers with developer and blix for the given amount of time and then wash them under the faucet with running water. This way the wash is quicker and no need to bother with the test drum. The beakers a small, but if you roll the print into a cylinder diagonally, you can process up to 4x5" that way. Try it, you might find it quicker.

Eugene.

 

[DREW WILEY]

An unrelated reason for doing test strips exactly the same way as final prints : allegedly there's an
interval of time needed for the latent image to fully "set". If you just pull your sample from the enlarger and right into the dev, it might come out different. I've heard anything from 30 sec to 2 min
with Fuji papers before they should be developed. I've never tested for this myself; but then, I've
never processed a sample that soon anyway.

 

[anikin]

Drew,

In theory you might be right. In practice, i have not seen any difference. Anyway, the test strips are just for getting close to the right filtration and expose. For fine tuning, i do a full size print anyway.

Eugene.


Sent from my iPad using Tapatalk HD

 

[wogster]

An unrelated reason for doing test strips exactly the same way as final prints : allegedly there's an
interval of time needed for the latent image to fully "set". If you just pull your sample from the enlarger and right into the dev, it might come out different. I've heard anything from 30 sec to 2 min
with Fuji papers before they should be developed. I've never tested for this myself; but then, I've
never processed a sample that soon anyway.

So how does it work in a machine like a Fuji Frontier, where the laser paints the image on and then it immediately goes into the soup? :munch:

 

[RedSun]

I'm not sure the extra "pause" would make any difference. But for me, it already takes me about 2 minutes to load the exposed paper to drum, seal it, walk to the wet side and load the drum.

 

[RPC]

Red Sun, why do you use drums? When I switched from drums at high temperature (like you used to have to do in the past) to trays at room temperature, and didn't have to wash and dry the drum every print, my productivity increased manifold. I think this is one reason many darkroom workers stay away from RA-4--many still believe you must use drums or processors.

Drew, how long do you wait before putting your prints in the developer after exposure?

 

[RedSun]

I spend most of the time on test prints, instead of the final prints. For large prints, I have several large drums, like 28xx and 3063. They are good for one day's work and I do not really have to wait for them to dry. For test prints, I mainly use test drums. I can just try them with towels. It is not too hard. I still print test strips to calibrate my Colorstar, then use 4x5 for to test print. Colorstar does cut down the numbers of test prints, but I can't trust it 100%. So far, this process has worked well for me.

I still print B&W with open trays. That is a different story.