Category: coursenotes

from lectures and presentations I’ve taught

Paper: Flash or Burn

Posted on Posted in coursenotes, the Lab, The Positive1 Comment

flash and bump exposures in the darkroom

Photography is a compression algorithm; a form of making smaller, of reducing without losing meaning.

The Hard Scenes

snow, big blank grey sky, interiors with bright window – these are challenging for the tone, the detail as meaning art practiced by most photographers. Photographers pride themselves early in their efforts in bringing ‘detail’ to art- details are the truth, but a devil to manage.

Photography is always a demonstration and an example.

Pre flash’increases’ sensitivity – gets the exposure started

Post flash ‘decreases’ contrast – adds (visible) tone to the highlights. Shadows are also affected, but those at maximum black can’t get darker. The deep grey shades are darkened, but this may not be noticed, or important to the image effect.

In general viewers respond in stages to the picture. First, they see overall object, with inspection they move to detail – most people approach pictures with notions based upon their ability to produce, therefore they are naive, taking cues from their “what is it” approach from pre-school life. With maturity they can move beyond what can be done by them; beyond hand waving or finger pointing.

vcPapersBumpNeg.001
overview motivation

pre-exposure and post-exposure. We mean non-image producing exposures; those made without a negative in the light path. I was taught that they were called:

  • bump: those pre-exposures which raise the sensitivity of the emulsion. overcoming the ‘inertia’ – lazy halides are awaked just before ‘dawn’
  • flash: those post image exposures. lower the contrast of the emulsion. this drops the highlight down the the curve

With bump raising the shadows up the curve, and flash lowering the highlights down the curve, we get a longer straight line image; more linear. This linear image is what a digital sensor provides. Straight line, not S-curved response.

Burning in the highlights, those dark negative areas, may take many hits of the timer. They also may seem to never bring out image detail. This is the opportunity to bring out more filters with multigrade paper. It also may signal the need for “bump” and/or “flash,” exposures.scn_BumpFlasht

The exposure light is most often the enlarger light; just remove the negative – fiddle and go. You can also use a small penlight, or digital controlled led like those made by RH. The color of the light has some effect, but the key use of a color flash is to hit a Red safe emulsion with an OC filter safelight. This is a very effective highlight pickup. Slavich paper, and litho film, exposed for 30 seconds to an OC filter at 3 foot drops almost another grade of contrast, most visibly in the highlights – perfect way to bring in detail that is difficult to burn in without that tattle tale grey featureless tone.

I’ve tested the color of light used for multigrade and have been unable to measure significant difference to 0 or 5 filters. Some, but not enough to warrant the change. Instead I usually bump with the filter I’m going to first expose with, and flash with the filter I just exposed with.

How Much: using Ilford MG fiber paper base exposure of 8 seconds, a 3X burn-in was replaced with a 3second ‘bump’ and a 5second ‘flash’ – giving details in the highlights that the burn hadn’t given. In other words 3 burns was just a waste of non-image forming exposure. The bump and flash equal to one burn provided image definition in the highlights. This process also made the edition of prints easy, and repeatable.

A Digital Way

With a digital process, the flash/burn doesn’t happen – isn’t used, since changing numbers is done in other ways. Ways such as luminosity masks; tonal overlays; local mask with additional manipulation. Even pulling into one image elements from different exposures. This can be done using dedicated HDR tools, or blunt force select, adjust, copy, paste actions.

Silver Bullets: Darkroom Rumors

Posted on Posted in coursenotes, labnotes, the Lab

The biggest detour is the detail. Paper clips and pencil sharpeners are the enemy of good writing; so too the enemy of good photography is the search for a better developer, lens, film, or, worst of all, opportunity.

Opportunity doesn’t knock, it hides right behind you.

Students teach their delays to their teachers. In teaching adult learners, while also teaching full time students, I noticed a significant differences. Those people who had to use the picture made better pictures earlier. The just followed the notes on the wall; used the chemicals provided; bought the student pack from the local store. At the end of a month they were making prints and talking about elements other than the ‘how do I’ of photography.

There were some who took to the process quickly, effortlessly absorbing details of the process, while also shooting. Shooting a lot. In fact, that was the secret of the successful student — they advanced themself — dedicated effort. They took the assignment: ‘a roll a day for a month’ in earnest, even extending it to the entire first year.

Basic Silver

richard.L6980webionaire
Three Kings

…. In the chemical age, in every age of commerce, we move among choices; are moved, actually, thinking we have choices, so there is the belief that we can be better, newer, improved with only another mixture. Rarely is that true.

These developers are my at hand mixture. LPD, Dektol, & D-76. I keep them mixed because they are useful, and are delivered as a powder. These days, LPD is also sold as a a liquid. I always suggest to the novitiate that they buy liquid, even though you are paying for water, you are getting freedom from air borne chemical dust. This is as close to magic as we get.

Basic Bullets

My key point is that those who pursue a better developer/film/camera/ .. anything such as that, lose sight of the image; what it is, where it is, and why. To cover the lack of understanding of the power of an image, or in being lost to understanding aesthetic growth, or “shock,” those folks cover their lack with a homily about being after the process or the print. They are only lost, and covering their tracks. They are only addicts, not artists.

The magic bullet isn’t something you will buy; it isn’t something outside you that is missing. You lack the magic.

Besides, silver bullets always go bad, and actually carry little impact.

The Magic Beans, as exchanged in the halls of the camera cult, are Amidol, Pyro, and Glycin. I have posted about Amidol; while Pyro has so many vocal advocates, just ask ‘google’ … however, Glycin is do some airing out.

GLYCIN

In the beginning there were several beginnings — however, the history of the Camera Crafters is drawn across the landscape in the Zone Shades of Ansel Adams.

This: “With some papers glycin gives a light “stain” to the very high values and  this appears as a “glow” which I have found rewarding at times. Usually a slow-working developer, glycin is sometimes preferred when a considerable number of prints are to be developed together.” Ansel Adams, The Print

His first series of technical articles was published in Camera Craft in 1934, and his first widely distributed book, Making a Photograph, appeared in 1935. Most important, in 1936 Stieglitz gave Adams a one-man show at An American Place.

So, Glycin — a trademark, which is close enough to ‘glycerin’ which was used in the darkrooms of dye-transfer printers, but definitely not the same stuff.

this is glycin the developer

/// BACKFILL CHEMISTRY NOTES

Haist: 174, Catechol (1,2-Dihydroxybenzend) ; Pyrogallol (1,2,3-Trihydroxybenzene)

catechol has been reported to be capable of image development even in the presence of considerable amounts of silver halide solvents, making this developin agent suitable for combined developing and fixing solutions.

Pyrogallol.. in developers containing low concentrtions of preservative, the oxidation products of pyrogallol development produce a residual yellowish-brown stain. This stain reinforces the silver image and is expecialy effective in obtaining maximum emulsion sensitivity and fine grain from the photographic material 

the possibility of providing developers that improve both the graininess and sharpness was the objective of a study by Alman and Henn. [Effect of developer composition on the structure of photographic igmages. Phot. Sci. and eng.,5:129 1961

converting a developing agent into better surfactant will improve it electron-transfer capability and, hence, its ability to serve as a developing agent. [haist, 170]

developing agents

  • glafkides [69] photographic chemistry, vol1, 1958, 112-131.
  • mees [70] the theory of the photographic process, 1942, pp 331-373
  • henny and dudley: [71] developers and theory of development, handbook of photography, 1939,ch. xi.
  • Lambert, Pyrcocatechin, Anthongy’s Phot. byull, 33:74 (1902)
  • Archer, 1851
  • William Evan, New Ways with Pyro, Am. Phot., 39(5) May 1945
  • Behrens, A Versatile Developer: Pyro, Am. Phot., 43(7) 1949

1948: Kodak lists SD-1 for pyro stain. SD means special developer; little use. Kodak needed a tanning developer (they had one) but they didn’t want stain.