Dispelling myths in color processing

Having lived through a lab H2 explosion that put a huge dent in a blast door, and seeing some at Cape Canaveral (or Disneyland East we used to call it until Disney built one in Orlando), and one at EK, I have a VERY healthy respect for Hydrogen. It explodes fast and easy. Ask anyone who rode on the Von Hindenberg.

 

Use nitrogen or helium. But, helium is quite expensive compared to nitrogen IIRC. They used to sell small lab cylinders of several gasses very cheaply and they last a long time. I can get a refill on my big nitrogen tank for about $25. I own my own tank, but usually you rent the tank. This extends the life of all photographic solutions, BTW.

 

On cost comparisons of color chemistry above, I did neglect to stress the potential cost savings of using Tetenal chemistry rather than EK chemistry. Sorry for the omission.

 

Ron Mowrey

OT: according to some research published in the 90s, hydrogen doesn't quite deserve the bad rap it got after the Hindenburg disaster. Apparently the explosion got started because a static discharge ignited the canvas covering, which was painted with aluminum powder (used in rocket fuel) and cellulose nitrate (gun cotton). Oh, the humanity!

Peter;

 

I know what you are referring to.

 

The Hydrogen explosions that I have seen or been involved in were so rapid that high speed photography was unable to catch the actual explosion. Our camera had a gear shift and transmission to get it into high speed, and consumed over 1000 ft of 35 mm film in much less than one minute and could not capture the explosion.

 

The only thing that was seen was the fire after the explosion and the debris flying. What I saw when the first Centaur exploded looked like a blue flashbulb going off and then about 5 minutes later the shockwave hit me. I was 20 miles away. A friend of mine about 2 miles away from the explosion was knocked over and bruised and battered a bit.

 

OTOH, I have safely walked by gallons of liquid H2 at the Cape and we kept H2 in our research labs at school and at EK. It is a double edged sword and like all such objects must be treated with extreme respect.

 

I'll pass on Hydrogen. The energy is too high for me. And 'maimed' is such an awful word. So permanent and ugly!

 

Be safe, don't use butane, propane, heating gas, or indeed any flammable gas for protection of photographic solutions, even if they are totally inert photographically.

 

Nitrogen, Helium, and Argon would be my choices.

 

Thanks though.

 

Ron Mowrey

Interesting thread! I found a couple nits which I will now pick.

 

Process EA-5 (for aero reversal films) is similar to E-4. In fact, if you have any E-4 films around, Process EA-5 may be the most convenient way to process them.

 

Process E-7 exists, at least on paper. It is functionally equivalent to Process E-6 except it used published formulas rather than proprietary chemicals supplied by Kodak. 20 years ago there were large volume independent photofinishers who mixed their own processing solutions. They used Process E-7 under license from Kodak. There may be a lab somewhere that still does this, but I'm not aware of one.

 

Blix is a term copyrighted by (I think) Agfa. Kodak refers to that combination as a Bleach-fix. There was a bleach-fix designed for film in Process ES-8. (The purpose of Process ES-8 is left as a research effort for the interested reader.)

Ron;

 

Blix was actually used in 1965 and earlier at EK. Marketing didn't like the name. In fact, the marketing guy that we worked with said it sounded like a kids toothpaste.

 

Anyhow, a competitor, not Agfa, trademarked the name. I'm not sure, but it might have been Hunt or perhaps Pavelle. (there is much more to this story, but I don't care to go into it here.) EK continued to use that name internally, and the first bleach fix that was used for a continuous process was called Blix 1066 for the month and year it was first put into testing in KRL. It was used to process the first experimental rolls of what was to become Ektacolor 70 paper. There was an earlier Blix 4 used internally but it was not stable enough for a replenished process.

 

E5 is actually similar to E3, in that it has no prehardener. E4 had a prehardener and ran at 85 deg., E3 ran at 75, and E5 ran at 70. I just looked up my E5 manual. Unless E5 was like E3, and E5a was like E4? Could that be a possibility? When I did aerial Ektachrome we always called the process just E5.

 

The only published formulas for E6 that I have found are not correct in several aspects. How does this relate to E7?

 

There are several more processes such as VNF-1, your referenced ES8, and etc. I would like more information on them to satisfy my curiosity. Perhaps someone could do that.

 

Thanks much.

 

Ron Mowrey

Rowland -

 

I would like to add to your comments on item 11.

 

Kodak papers have a different spectral response rate than Fuji papers, and the Kodak Film is "centered" to that Kodak Paper spectral response.

If the paper is weak in the blue than the film will compensate for that with the yellow response. Just like Fuji with the Magenta/Green relationship).

The machines in general compensate for this - and digital machines can do a much better job at it (because they have a lot more range.. details here are too much)

The optical equipment is set to a happy medium and can only achieve a compromise however if the negative is normally exposed + or - 2 stops chances are good it will be a very good reproduction of the original negative. It is all in the response match up and how well the machine can compensate for the difference (the machines have limits).

There are alot of factors that go in to centering - or balancing the machines scanner to the paper. This way it looks at the negatives in a skewed manner (skewed by the paper brand/type) too many technical details for discussion here. And this is where most people go wrong when they set up a machine - they might change papers but ignore to change the Scanners filters (it's skewness to the paper) this causes the machine to lose centering and therefore it cannot reach the range necessary to compensate for what it has to do - and the results you get are blah..

Unfortunately most people do not realize the amount of technology that goes into producing accurate photographs .. it is astounding

I need to update some of the nits that I picked yesterday.

 

Process EA-5 has been replaced by Process AR-5. The aero films now include hardener. Process AR-5 uses EA-5 chemicals except for the prehardener and neutralizer.

 

If anyone has old unhardened films (E-4, ME-4, EA-5, etc.) your options for processing are probably limited to Rocky Mountain Color Lab and Film Rescue International.

Ken;

 

I agree completely with you. It is so technical that I didn't go into any of that. Suffice it to say that operator error is the source of a lot of the problems.

 

Also, although Fuji may use slightly different spectral sensitizing dyes, I have tested many sensitizing dyes in papers, and if the right settings are used the prints are excellent. As long as the paper has an appropriate behavior according to the silver criterion mentioned above.

 

In my opinion only, the Fuji spectral sensitization is not sufficient to cause the myriad of reports that I see about bad prints. I have gotten excellent prints from Fuji and Kodak negatives on the same Supra III and Endura papers with virtually the same color balance and exposure times from a good negative. Although I have used all versions of Kodak papers, and most EK films and many Fuji films, I must admit that I have never used Fuji paper so I cannot speak authoritatively about it in any way. I can make some observations though.

 

Of great importance is the 'gap' between the green and red sensitizing dyes, and the relative ratios of the blue, green, and red speeds of color paper. Upsetting these four factors can really mess up the color reproduction a paper yields unless the film has a built in compensation, but then this is detectable by other means and can be corrected for in printing. I have done that as well.

 

Correct tricolor printing should eliminate all of these problems by using a common denominator in exposure, the separation filters.

 

Very complex though, I agree.

 

 

Ron;

 

Thanks for the updates. So there is a new Aerial Ektachrome process with prehardener. That explains some of the discrepancies between reports about this film and process.

 

Ron Mowrey

For what it is worth, I would say from my perception, Kodak Professional Paper is sharper than Fuji Professional Paper but the Kodak paper smudges more easily than the Fuji paper. ;-)

HC;

 

That is an interesting observation. I have found that each generation of Kodak color paper seems to get better at smudging or fingerprinting.

 

The Ektacolor 70 surprised us by being so sensitive to fingerprints giving cyan prints and smudges so easily, so it was an ongoing effort at EK to remove this defect.

 

Supra III seemed pretty good, and Endura has seemed even better. I have not gotten any fingerprints or water spots on my Endura so far. I hope my luck continues.

 

I have never heard that comment about sharpness.

 

Thanks for the information.

 

Ron Mowrey

According to Kodak's Web site (http://www.kodak.com/US/en/motion/products/chrono3.jhtml?id=0.1.4.20.6&lc=en), process ES-8 was used for KODAK EKTACHROME SM film, 7244. That was a "Super 8 color reversal film for automated processing in Spermatic Processor. Process ES-8. Announced 1973."

 

From this meager information, I can only conjecture that the main users of this film were producers of those "8mm special" pornographic featurettes that I remember furtively watching with friends in college.

You are welcome to the observation, Ron,

 

Another perception is that Fuji papers are stiffer, especially Crystal Archive Paper. So I guess they are good for the retail consumers who pass around their 4x6 prints. And it should be no surprise to see business name cards printed on Fuji paper.

 

Since I mount/frame large prints and sleeve small ones, I'll go along with Kodak papers, ;-)

Dear Ron: many years ago I went in a "Hosemaster Light painting course" by Aaron Jones, here in Finland. He had great pictures that were made on velvia - then a new film. We had not so good results with Velvia, purple whites and so on. I asked about that from him: His reply: The Fuji version of E-6 requires a water pre soak for 2 minutes in the beginning of the E-6 process, after that-NO purple or other color shift. No one did that first water pre soak then ( maybe not even now). I got myself the same in studio machine as Aaron: JOBO ATL 2 plus. Yes with water fí²³t bath, no color shift-perfectly beautiful clear whites and generally better color rendition. Are you awae of this first pre soak step??