Experiments with RGB-colored screens... a la Dufaycolor & Autochrome

[Mustafa Umut Sarac]

Chris ,

I could not believe my eyes , really excellent. But may be this excellence comes from the excellent dyes of ektachrome ? What do you think ? There are parallel lines at the screen , is that because of television ?. May be you can experiment with plasma tvs . I could not read the entire thread but I liked the colors very much but as I said before they are look like old Ektachromes.

What do you think ?

Umut

 

[holmburgers]

Hi Umut,

I agree with what you say. The characteristics of the slide film might play a large part in the final look of the picture. For instance, what would Velvia do, and what about Astia? How different would they be? This is the exciting part I think!

Also, can I achieve slower but more saturated plates by underexposing the slide reseau? Likewise, can I get faster plates with washed out colors by overexposing the slide? Furthermore, the exposure and contrast of the b&w positive will be important in its viewing characteristics and color intensity.

And yes, the pattern from the TV is clearly visible. I definitely wish to experiment with higher-definition screens, like plasma or LCD, etc. Computer monitors are ideal because they match the aspect ratio of 4x5" film exactly and have higher native resolution. The only problem so far has been the fluorescent back-light.

I am going to stick with the TV for a while however, since I've managed to get such neutral screens and in theory, the resolution should be the same as watching TV and usually people don't complain about it then.

I just hope that E6 in 4x5" stays available.... :/

 

[Ray Rogers]

Computer monitors are ideal because they match the aspect ratio of 4x5" film exactly and have higher native resolution. The only problem so far has been the fluorescent back-light./

Many new laptops have gone HD meaning something like movie theater aspect ratio, so they may not match 4x5 much longer...

Newish (?) laptops I was looking at here have LEDs instead of the Fl tubes.

Better?
Worse?

 

[Mustafa Umut Sarac]

Chris ,

Its seems to me there are 4 ways in front of you. First one , finding big television with more dot density and produce your screens and theorically , if you reach to the top , obtaining the same film look from the ektachrome with your screen.

All you do is trying to produce more dense screens. If you find 500 times more dense screen , screen will be invisible and you start to use the bare film.

Second path is to produce same chemical screens with inkjet printers , free from the using the dyes of ektachrome. So you will never find the same panchromatic emulsion and produce a new autochrome.

Third path is to mix your own color perfumme from ready made dyes.

Fourth path is to produce of your own dyes like old timers produces their essences before producing perfumme.

What do you think ?

Ray , I researched daylight LEDs and found they are still very very far from the daylight. They have steep green and blue peaks and far far away from producing the real white or colors.

I used daylight FL tubes at prepress works and FL tubes like film but LEDs are like digital.

Umut

 

[holmburgers]

Ray, are those wider aspect ratio TV's extending the total resolution or cropping within the exisiting image area. I would assume the former, so hopefully we won't lose resolution?

I would think that LED's might suffer from metamerism less than FL, but I don't know, perhaps Umut is right about the peaks.

I am content to reach the theoretical limit of TV screen plates on slide film and I think I will shoot for that. But the real goal of all of this is to free us from the bonds of commercial color film, and yet paradoxically this is impossible in my current scheme. So yes, ultimately I think that there has got to be a different way.

Since color printers use subtractive inks the only way to really achieve an ideal situation is to hack the ink cartridges and fill them with dyes. This could be fun at some point...

However, I do believe that perhaps the Lumiere's achievement has still not been surpassed, and working with more organic things is always more fulfilling than computers. I'm excited to see some of the efforts of people like Shaz ('autochrome latex' thread).

Now what exactly do you mean by perfumes? Like potpourri, a mixture?

 

[Stephen Frizza]

something that i find has effect on colour in relation to screen is not just the colour of the R G and B in the screen but also the black and white films panchromatic sensitivity and the films contrast. you will find some black and white films yield a bias to red or yellow or blue etc.... and that the tonal range of the film its Dmax etc makes a difference to final colour.

 

[holmburgers]

That's a good point. Looking at the data sheets for various films might be a good starting point. If a 47B and 29 wratten filter have drastically different times, then perhaps it is not a great film for the purpose. Or might have to be adjusted.

Many variables = many options!

 

[Photo Engineer]

Look at the wedge spectrograms of the films in question and compare "speed" or "energy" at the wavelengths of your filter sets. This will give you a rough approximation of what response to expect from the film with a separation filter. Of course, to be fair, the exposure is actually the integrated area of the sum of the filter bandpass and the spectral sensitivity.

Sorry.

PE

 

[Mustafa Umut Sarac]

Chris ,

I meant perfume , another thing French people do well. Its like autochrome dyes , mixing chemicals and get a decent result , worth to read Patrick Süskind book. Man is a genius and get every fragrence from miles away and interestingly he has , his body no fragrence. He kills the young virgins , alembic them and get his results. Finally he decides to invent a fragrence for his body , people like it and eat him.

May be you can invent a dye for your beard and make every women fall in love to you
Blackbeard

Umut

 

[holmburgers]

EPIC Fail

Ok, last night was both good and bad. Good in that I successfully reversal processed 5 sheets of film, bad in that the 6th and unsuccessful sheet was my screen-plate positive.

I honestly can't say what went wrong. Basically it's as dense as a black hole and would take a nuclear explosion to project it; however, the image is in there, you just have to hold it up to a bare bulb to see it. Not to mention there are very funky looking swirlies, anomalies, etc., all undoubtedly due to the gelatin-binding.

It was on Delta 100, just like the previous one, and I shot it at ISO 12 (screen-plate figured in), whereas the previous one, as seen above, was shot at ISO 25 and sent to dr5 chrome (rating the film itself at 64)

One screen is a bit denser, so I'll test that, but I don't think enough to account for this total failure, nor do I think that my reversal processing lost that much speed, since the other 5 sheets had a shot or two on DLTA 100 shot @ 75 and looking good.

So, there's got to be something going on with the gelatin binding that's destroying its sensitivity, or I'm underexposing, or both. At any rate, the anomalies present in the image and the labor required to bind the two sheets is worth abandoning this method for the time being.

I'll try to post an image at some point.

So, quite literally back to the drawing board. PE suggested carboxy-methyl-cellulose to bind the sheets, of which a substitute is K-Y Jelly. So that's worth exploring, and if it doesn't work, hey, at least I've got some K-Y.



Other thoughts; how about a plate holder with some kind of pressure/spring-loaded glass to press the sheets together. This would be great if I could find such a unit, but I like the idea of being able to use pretty much basic film holders (albeit slightly modified) and elimating another substance that the light has to pass through. But, I'm not above it..

And what about static electricity? If I could somehow get these two sheets to have an affinity for one another, I'd be ready-set-done. As it is, without an adhesive or pressure, the sheets will invariably not making "pure" contact.

Lastly, S. Frizza's method was to introduce a slight bend in the films. Although I think it's a good idea, I don't know how I would achieve this in the holder, nor do I like the idea of bending the film plane. But Stephen, what kind of film holder did you use for the bend?

Thanks y'all... pour fourth your best ideas, help!

 

[holmburgers]

Here's the botched positive.

If you mozy over to this thread... (there was a url link here which no longer exists) ...you'll see that excellent results were obtained in the same batch of films.

I did have a problem with my processor where I noticed two films were sticking together a bit, but I'm 98% sure that this wasn't one of them, since I could see the damaged emulsion and unless my brain & eyes are playing tricks with me, there's something else to blame. Plus, the sticking was only in one corner... long story short, pretty sure that's not the culprit.

It seems surprising that there's so much information in such a dense film; I had to shine a lot of light thru this.

At any rate, notice the imperfections and craziness going on. Admittedly, some of it looks kind of cool though.

But, is it possible that there's some effect on the emulsion, or is it just horribly underexposed? Like I said in my last post, it doesn't seem logical that it's underexposed.

On the bright side, the grid-pattern is very sharp and regular looking (as far as I can tell) which means that binding is ultimately gonna work.

Also, recall that I noticed a significant amount of purported 'acutance dye' leaching out when I used the gelatin binder.

Discuss amongst yourselves...

Everyone have a good weekend!

 

[Stephen Frizza]

Lastly, S. Frizza's method was to introduce a slight bend in the films. Although I think it's a good idea, I don't know how I would achieve this in the holder, nor do I like the idea of bending the film plane. But Stephen, what kind of film holder did you use for the bend?

Thanks y'all... pour fourth your best ideas, help!

you need your screen to be slightly oversized and being on duraclear it is a thicker base than the film. By placing it into the slide a very slight curve is created see in daylight and sacrifice a sheet of film experimenting with the curvature until it is in appropriate contact with the film and not too extreme as to greatly effect focus and also allow the slide to pass back and forth.

Alternatively if your creative line the film track of the darkslide with a spacer of thin mylar or alternate plastic so the film must bend when inserted. I'm sure there are many other ways you can create a contact curve to the film.

While many will dislike the idea of the curve application for the obvious optical issues is it a very effective way of getting easy contact.

~Frizza

 

[holmburgers]

...line the film track of the darkslide with a spacer of thin mylar or alternate plastic so the film must bend when inserted.

This seems doable to me.

 

[holmburgers]

As for the failed positive. I'd like to lay out the entire course of its "life" to help establish what might've happened to it, much like a detective would.

Just the facts ma'am

Delta 100 - Fresh

1st, the screen and film were bound with a solution of 3% gelatin, 5% sorbitol and <1% photo-flo. The sandwich was hung to dry in dark-bag equipped with ventilation for 24 hours. This was then loaded in a film holder. Leftover gelatin on the registration board had acutance dye in it, evidence of leaching.

Next, exposure. The screen attenuates 2 stops under tungsten light. Banana read EV 9 and I gave an exposure of 8" at f/8. I called this ISO 12 at the time, putting the banana on a Zone 7-8ish (if my calculations serve me). That should've been plenty of exposure, seeing as my tests of Delta 100 in the same processing batch indicated that ISO 75 was good if not a smidgen underexposed, ergo ISO 64 is ideal (seconded by dr5's recommendation).

Now, the sandwich had to be unbound, and this was achieved by soaking the two sheets in warmish water, not greater than 30°C and working around the edges with my fingernail, hence many of the imperfections. I then rubbed the emulsion side under water to remove as much gelatin as I could, though it didn't seem like there was much there. I figured that this would be bad if it prevented processing solutions from getting in contact with the emulsion. This was then hung in the same dark-bag and allowed to dry overnight.

Finally, I reversal processed it along with 5 other sheets according to the procedure outlined in this post -> (there was a url link here which no longer exists) All the other sheets came out perfect.

So, I know this is all redundant information, but I'm just really curious as to what the hell happened to this sheet of film. It was certainly put through its paces; multiple wetting and drying sequences in particular, but what could have caused this incredible density? The image I posted of it was a long exposure with a bare bulb directly underneath it, to give you an idea of the density. Holding it up to a window in normal room light reveals nothing. Presumably, if processed as a negative, the image would have been incredibly thin.

 

[Photo Engineer]

Remember that as acutance / trimmer dyes wash out, film speed goes UP.

PE

 

[holmburgers]

OK... that's very interesting! When I first read your reply, it seemed contrary to what I was experiencing with a dense positive.. thinking underexposure.

BUT, how about this...

the increased speed resulted in a higher-density negative image that therefore required a longer than normal bleaching sequence.

In other words... I didn't bleach out all of the negative image because more was there than expected, and in comparison to the slides that came out OK. Then, this leftover developed silver added nothing but density and decreased contrast.

Have I got it?! That means I'd just have to make sure to bleach sufficiently next time.

 

[Photo Engineer]

Actually, I have no idea. I think that the positive should have been lighter, so I just threw that in as a reminder.

PE

 

[holmburgers]

Hmm.. ok then. I thought maybe you knew something and were dropping hints.

Wow, this is almost as disappointing as the Kansas Jayhawks losing to VCU today... ok, not nearly.



The explanation of overexposure & excessive density, ergo too much silver to be bleached in a given time, could make sense, but I might be deluding myself as well. It seems pretty far fetched actually, now that some time has passed.

However, I get the impression that the density is not just underexposure, it seems like there's too much detail to have been underexposed.

Here, look at the circles I've drawn on the picture. At these points, the density is decreased for whatever reason and the positive image kind of shines through, suggesting that the whole thing is "veiled" in some way.

Now I'm really wondering about the 5% chance that this sheet got compromised in the processing stage.

 

[Photo Engineer]

How about something in the "glue" affecting the process?

Paint some glue on a sheet and expose. Then process as you did before and see if there is any substantial change.

PE

 

[holmburgers]

I might have to do that.

But don't gelatin, sorbitol and photo-flo seem like fairly harmless substances to a film? Generally speaking of course.

Ok, I'll devise a test in the meantime.

In the meantime, gute nacht!

 

[Photo Engineer]

IDK what might happen with that mix, but I would not suspect what you got! Something went on.

PE

 

[holmburgers]

Could the physical stress of the gelatin between the two sheets be a problem? I'm imagining some degree of shrinking when drying and some "activity" going on, perhaps on the molecular level. (obviously, I'm no scientist...) Also, peeling them apart might've been stressful.

Repeated wettings and dryings... etc.

Or, could the warm water have fogged the film? That of course, wouldn't account for the apparent under exposure.

There's simply too many variables at the moment. For all I know, it was my processing... (though seriously, I don't think it was)

Ugh. At any rate, I think that getting an optically perfect coating is going to be difficult, and for that reason alone it might be worth exploring something else. The K-Y for instance. However, if I try the gelatin again, I think I'm going to try a high gelatin concentration and two types of sugar (sorbitol and cane - to prevent crystallization), sans photo-flo.

You described the carboxy-methyl-cellulose as creating a flexible "skin" that could easily be peeled off. Would K-Y be similar? I have some of that strange "Cornhuskers Hand Lotion" which is mostly glycerin, and indeed, around the cap where there's excess goop, it dries to this strange rubbery consistency. Such a substance might be ideal.

 

[Photo Engineer]

Can't hurt to give a try.

Maybe something in the "goop" you used inhibited the first development step.

IDK.

PE

 

[holmburgers]

Maybe something in the "goop" you used inhibited the first development step.

That would fit my outcome I guess.

If so.. let's reason it out... the first dev was insufficient, i.e. weak negative image, this was bleached away, leaving an excessive amount of silver for the positive image.

That also might explain the points of more normal density. They seem to correlate with areas that "historically" weren't getting the best "gluing action", that is, right around the registration pins.

Some of the strange patterns in the image are definitely from the actual exposure, me thinks. Meaning, the patterns were recorded on the film during exposure because the gelatin wasn't optically cementing the two sheets together at those points. In turn, it would make sense that those areas received a higher degree of development, having access to the solution.

Thanks PE, the more input the better, even if we don't find the magic bullet, the more suggestions I receive, the closer we get to making sense of it.

 

[holmburgers]

Ok, so I stumbled upon some interesting information in Friedman.

p. 173 (2nd ed. 1945), Chapter 14.

Talking about dye-sensitization... The first sensitizing experiments were carried out by bathing the finished plate in a dye solution. Plates sensitized by bathing in this manner were quite effective in the new range, but unfortunately had very poor keeping qualities..., he goes on to say, This was traced to the removal of the slight amount of soluble halide left in the finished emulsion to give it keeping qualities and freedom from fog... a finished emulsion should contain approximately one to five moles of soluble brome per 1000 moles of silver bromide, in order for that emulsion to keep over a year...

From the first cementing w/ gelatin (1/25/11) to the separation, the sandwich probably sat for a solid week or more. After separation, which entailed full submersion in water with washing, it probably waited a whole month, if not more, before being processed.

Does the above theory still hold for modern films? If so, it's possible that the film was horribly expired by the end. However, I can't quite reason why this would have given me such a dense positive.