reversal B&W....chromes.

greenspun.com : LUSENET : B&W Photo: Alternative Process : One Thread

There's something new going on in film processing.

.dr5 , a reversal B&W process that produces spectacular chromes.

Chromes from 'any' B&W neg. film.

the scala alternitive.

Unlike SCALA, this film will print, scan, & dupe with ease.

Check out the posted URL for more details. ALSO, be sure To check out the 'FAQ'.

For those that have heard of .dr5 , we are now affiliated with The largest lab on the west coast. AIM a sister lab of A&I color.

This merger does nothing to change the quality. AIM will handle all Shipping and receiving.

Thanks for your time.

http://www.drwood.com/dr51.html http://www.drwood.com/dr51aim.html http://www.drwood.com/lab.html http://www.drwood.com/faq.html

Regards,

drwood

-- drwood (drwood@drwood.com), April 19, 1999

Answers

drwood,

Perhaps you can explain a little about your process. I've seen your site in the past and didn't get any technical info on your process other than your claims of it's performance (I havent tried your service so I can't comment on whether I like it or not). What I am curious about is what about your process is different than reverse processing the film using one of the many protocols that exist. For instance are you essentially doing a kodachrome type development where you are supplying a dye or is the image made up of silver? I've done reverse processing of many of the films that you list on your site and am curious as to the differences between what I have done (dev, bleach, reduce, dev, fix, wash) and your process.

Thanks, Fritz

-- Fritz M. Brown (brownf@idhw.state.id.us), April 19, 1999.


..while ill not divulge the recipe, what i do, inprinciple is the same as any other reversal process. i can tell you that what's in the soup is different than anything you can buy in a kit. there are also many quality control issues that have come up over the years ive been doing this, and although only for myself,,, and now for everyone else. issues such as 'water, agitation, ect..a chemistry degree did hurt along the way either.

i always say seeing is believing. a roll in hand is better than anything i can say.

regards,

dr

-- drwood (drwood@drwood.com), April 19, 1999.


WOOPS! ment to say... a chemistry degree 'didnt' hurt along the way eitherdr

-- drwood (drwood@drwood.com), April 19, 1999.

David, I'll agree that quality control issues have a definite effect on the outcome. What kind of issues do you think are the most significant that you have overcome in your process. For instance in my locality the water is of very uncertain character and as a result I use reverse osmosis followed by a Milli-Q system for my water. Agitation always involves some amount of witch craft. Tempurature control, consistant reagent strength, and adherance to consistant protocols all add to the final outcome. Are there other issues that you have found to have an effect on the slide?

You also mention the different developers that you use to effect tone. I have use a sulfide second developer to acheive a sepia slide and gotten really nice results. I have also considered working up a protocol using pyro to see what effect a tanning developer would have. I expect that after a long and drawn out development period it would result in some interesting results. I know that you dont want to reveal your specific developer recipe, but what kinds of developers did you experiment with and what road blocks occured and what epiphanies came your way.

Lastly I am curious about some things you mention in your FAQ. First is the 10 zone latitude. Do you have some densitometric data that we could see to evaluate the density curve of a transparency developed using your process? This also gets to the statement that your process is not applicable to the zone system. Using the zone system involves controling both the exposure and the development and logically sending your film to someone else to develope without compensation obviates the use of contractions and expansions. But, have you tried to alter the first development to effect the contrast? I havent done anything along these lines myself, but since the second exposure and development is quantitative, expanding and contracting in the first development step should have the effect of expanding and contracting the remaining image also. Admittedly you would probably have to play around with the solvent componant of the first developer to get the highlights right, but it just might work. Like I said, I haven't tried zone manipulations in a reverse processed film so I could be missing something.

-- Fritz M. Brown (brownf@idhw.state.id.us), April 20, 1999.


..i think you answered the major issues regarding the pitfalls of reversal processing. the same issues apply to color.

the tone issue also applies here. there are many components that affect the tonality of the final product. i would stay away from pyro as a second or first developer. you need to work with straight development, and not a stain. there are many tricks to tanning or giving the film a solarized look.

the dmax in the dr5 chromes range form almost clear 'with detail' in those areas, to the blackest blacks with the same detail. the densitomiter readings run from 0.15 - 2.97 . there is no real way to read the finite details either. seeing the stitching pattern on a black shirt is not readable on even the best densitomiter.

the zone system if fine as its own entity, but its the zone system as it is that cannot adapt to dr5. to change the product to comply with the zone system would be foolish.

your additional email in regards to panchromatic film is incorrect as i know it. i think you ought to look up how B&W film is panchromatic.. this is a whole other subject we could debate, but in short B&W film does see color! this is why we have filters for B&W film. while B&W film has no dyes, the color it sees is represented by shades of gray. while ill not divulge what brings out the characteristics of panchromatic film under dr5, .dr5 changes the once neg. film into something completely different. it handles light totally different than its negative counter.

the word panchromatic means 'sensitive to ALL colors".

regards,

drwood

-- drwood (drwood@drwood.com), April 23, 1999.



You need to re-read my e-mail. What I said was that once a silver halide grain is exposed it does not have any information as to the wavelength of the light that exposed it. Therefore any developer will "use the panchromatic nature of the film". Since there is no wavelength information stored, no developer can "use the panchromatic nature of the film" in any way other than any other developer. So your claim that it "brings out the panchromatic nature of the film" seems a bit specious.

Here's the experiment that will test that. Take an image of a color pallette and develope the film in both your system and in another (say as a negative or using Deitrich's protocols, whatever)to the same contrast index. Then observe the tones in the red and blue sections of the pallette. If you have effected the panchromatic nature of the film, then the relative sensitivities will have changed. In other words, the color sensitivity will have changed. I don't believe that a developer can do that since there is no wavelength information stored in the exposed silver halide grain. Therefore your developer, or any other, cannot change the panchromatic nature of the film.

Also panchromatic may mean sensitive to all wavelengths, but in practice that is not true. Look at the sensitivity curves of the various films and you will see different sensitivities to different wavelengths of light. For instance Tech Pan has a higher red sensitivity than most other panchromatic films in common use. No development system can alter that. It is a function of the film at the time of exposure, not at the time of development.

One other thing. I've got chemistry degrees too. More than one.

-- Fritz M. Brown (brownf@idhw.state.id.us), April 23, 1999.


One more thing. I think that you and I are getting into something of a pissing contest here and that is not my intention. I am just trying to figure out your system and carry on a conversation.

I look forward to your answers.

-- Fritz M. Brown (brownf@idhw.state.id.us), April 23, 1999.


A couple of more things (God, will I ever shut up...)

Concerning the 10 zone dynamic range you say you get. When I asked for densitometric data what I meant to ask for was densitometry of films that have images of step tables so that we can see what the dynamic range of the film is. Basically the same data one collects when calibrating your film and development for the zone system. Obviously each curve is going to be specific for the film being tested and the range wil be dependant upon the film choice, but that is how we can see what the film performance is.

This also gets to some of the zone system questions. The zone system can't work unless you have control over both the exposure stage and the development stage and can alter both to suit the specific image. It is most applicable to negatives and is something of a mute point when talking about chromes, but the principles of altering exposure and development in tandem does have some applicability. I think that the biggest reason that your process isn't applicable to zones is that you dont have the coordination between the exposure stage and the development stage.

-- Fritz M. Brown (brownf@idhw.state.id.us), April 23, 1999.


we will agree to disagree on what can be brought out in panchromatic film. panchromatic film sees color and stores it. end of story. dr5 in its nature and composition enhances B&W films ability many steps further than a normal development. other than telling you it does, i cannot say anything else without getting into the root of things. this im not ready to do. before you blast something it would be best to have film in your hand. then if you find the claims i make to be false,, blast away. till then what you state is like saying a car is crap without driving it... drive it! i can tell you ive blown every tech ive met,, from kodak, fuji, and many labs including the largest one on the west coast.

i have never gone to the extent of testing the films range in this manner. densitomiter readings in range only. this is a 'by site' item. id be interested in seeing such a test on the processed film.. i have no need for this info, but you might.. maybe you ought to test it?

regards,

drwood

-- drwood (drwood@drwood.com), April 23, 1999.


David, I hope you had as nice a weekend as I did. Niceties aside, let's dispense with the panchromatic argument once and for all. Panchromatic film can be exposed by a broader range of wavelengths of light but it in no way stores information as to the wavelength of light that exposes it. A latent image speck formed by one wavelength of light is indistinguishable from any other. If anyone wants to read further on this material (this conversation is occurring publicly after all and we need to consider our audience) read The Theory of the Photographic Process. It is published by The Macmillan Company of New York. I have no idea if it is still in print as my copy is really old. It should, however be available at your local university library.

Now back to the dynamic range portion of our conversation. Doing densitometric scans on step tablet images would probably be a good thing for you to do in the long run. It will allow anyone who is considering your service to evaluate the dynamic range properties of each film and decide which will work best for their purposes. Merely saying that Tech Pan is contrasty in your process, for example, isn't enough information. You will probably get a better response from people if they are able to evaluate before hand what the results will be rather than taking their chances and sending the results of a two day shoot off in the hopes that it will come back usable.

You seem to really want to not explain your process. I respect that but would like to offer an opinion. If you have done something truely novel, patent it. Then you are protected and can still open your process to public scrutiny and comment. If you are merely trying to protect a proprietary secret, then more power to you. You aren't going to get people who like to do their own reverse preocessing to use your service regularly because we do it for the same reason we do our own E6 processing, because it is satisfing to do it ourselves. If your process does something completely novel, we will figure it out eventually. Your best customer base is going to be those who want black and white transparencies but don't want to do it themselves. It doesn't matter whether your process is publicly known or not, those people are basing their decision to send their film to you based on service more than anything else.

I will test out your process and compare it to my own work. If you have any particular film that you think exemplifies your process let me know and I will include it in the test. All results will be publicly posted (probably to the film developing section of this board), good or bad. I agree that the final arbiter will be a piece of film in hand, but having characteristic curve data on your web site would greatly assist your potential customers.

Finally, about your having blown various lab techs, that is either a typo or more information than I needed to know :)

Cheers, Fritz

-- Fritz M. Brown (brownf@idhw.state.id.us), April 26, 1999.



I'm intersted in the above dialogue. B&W film giving rise to a silver image can be developed to give colours in a number of ways, I have my methods too. One is to use chromogenic dye couplers, another is to replace the silver of the image with varying amounts of various coloured metallic or organo-metallic salts, another is to use certain processing techniques which give variable dispersions of colloidal silver which, depending upon shape and particle size, will be seen as different colours, generally pastel and very beautiful and which will be somewhat dependent upon the original grey scale of the film and therefore to some extent on the colour luminosity of the original subject.

I have published a number of processes without patent because I believe we are the collective custodians of the the practise of the science, art and craft of photography. As such this knowledge belongs to us all. Also I have not the resources to comercially develop and police any patents which I could have appled for.

I congratulate any new creative process designed to extend the creative expression of photography and hope that you may feel inclined perhaps, at some point, to share the general principles of your methods, if not the exact formulations, as I have done in the few sentences above.

Wishing you all the best,

Dallas Simpson, photographic artist.

-- Dallas Simpson (dallassimpson@waterpump.f9.co.uk), November 18, 2000.


this is interesting...I've done some reversal processing & have had some fun with trying to develop kodachrome ( got a mediocre image )

what I'm wondering is....if B&W films are made panchromatic by using dyes to sensitize the silver to different wavelengths past the normal blue sensitivity...would it then mean that the color information actually does exist - just isn't used? In other words...could a processing system be made that "knows" which dye "saw" the light and made the silver halide exposed?...

-- rogerrrr (rogerartsax@aol.com), September 03, 2001.


Trying to answer to Rogerrrr, and casting a little more light on the "panchromatic" debate.....

It is widely known that most B/W traditional films are made up of two, three or even more distinct emulsions, each with different characteristics. The emulsions generally have different sensitivity and/or different wavelength sensititazion; this is done to optimize grain size and to render the characteristic curve straighter, because the single emulsion can have silver crystals tailored in size to the wavelengths it is sensitized to.

After development, upon projection, the densities created in the various emulsions build up, giving the total observed "negative density", actually the sum of the densities recorded by each single emulsion.

I think it is possible, reading the claims made by Drwood, that the .dr5 process exploits to some extent the different information recorded by each single emulsion, allowing for instance different degrees of development in high- and low-density film areas, giving better tonal range and shadow detail. If this is the case, we should more properly talk about film "pan-sensitivity", rather than "pan- chromaticity", although it is of course possible that the two concepts are somewhat related.

Hope these thoughts will help someway.... I think I'll have to give a try to .dr5 process anyway!....

-- Davide Butti (davide.butti@tethysonline.com), September 21, 2001.


FWIW:

I would have to agree with F.Brown's initial comments with regard to the emulsion layer. The wavelength information is not retained because the silver registers only that light of a given intensity passed through.

The retention of wavelength information is entirely possible and is the basis of the Lippman process which produced the first direct color images and is the basis, I understand, for contemporary holography. In the Lippman process the emulsion layer is backed onto a mirror of liquid mercury. The light doesn't merely pass through the emulsion, but is immediately reflected back. This "double-exposure" by reflection does serve to expose the grain differently producing a color image directly, though it can only be read correctly when struck by light at the appropriate angle, sort of like a daguerrotype.

At the same time, of course, colored filters also serve to differentiate different wavelengths when combined with an emulsion.

-- Cletus Dalglish-Schommer (cletus@ucla.edu), April 23, 2002.


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