Tuesday, January 21, 2020

Thoughts on the Intermediate Process

Selfie, Kodak Ektar 127mm on Cameradactyl OG, reversal processed Arista RC grade 2 semi-matte paper
Direct positive print

P1040673a

Certainly, casual photographers for decades have avoided the minutia of the intermediate process by choosing cameras and formats that offer a more instant picture-making experience. The average person couldn’t be bothered by F-stops and ISO numbers, they just want to push a button and see a photo. Which may be one reason why smartphone photography is so popular; the intermediate process happens behind-the-scenes, in software code and microscopic circuits, the modern-day equivalent of the point-and-shoot camera.

Processing Harman Direct Positive black-&-white paper through its regimen of developer, stop and fix (or in the case of reversal processing print paper: developer, stop, bleach, re-exposure and developer) certainly represents some kind of intermediate processing; it’s not as instant as a Polaroid, say (or Fujifilm’s Instax). But it’s more immediate than film, especially so when considering the many people who still use film do so as an intermediate image-capture medium that’s then scanned-to-digital and subsequently processed a second time around in order to arrive at a digital print, a kind of double-intermediate processing.

There’s also no arguing that prints exposed in-camera and processed directly afterward lack the flexibility that we have come to expect of modern image-making systems. Their usefulness is limited: the selection of large format lenses, apertures and focal lengths is limited; the tonal range is limited; the photographic sensitivity of paper is limited. But one often finds, to their surprise, that such limitations present a challenge that fosters a renewed sense of creativity; boundaries are often healthy for the creative process. In my case, I'm more satisfied by the immediacy of the direct print process, and willing to accept the tradeoffs in image quality or flexibility.

These days, I’d rather return from a photo outing with one good print in hand than a roll- or card- full of mostly junk. It’s a refreshing change, embracing direct positive prints and eschewing the intermediate process.

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Friday, December 27, 2019

Christmas Angel

“Christmas Angel”

I've been experimenting more with the direct positive reversal process for black-&-white print paper, and decided that, since it's two days after Christmas, it was high time to do a holiday-themed still-life. Naturally, I'm late; but there are twelve days to Christmas, right?

Today's a windy, wet day here in the high desert, not fit for man or large format camera, so naturally I figured it best to do the project under artificial lights. I don't have a stable of high-powered strobe lights, so daylight-balanced LED lights would have to suffice; the same lighting I use for my videos.

Here's the basic setup:

Christmas Angel studio setup

I've repositioned my studio lights to be more direct-on to the subject, which is a glass angel figure. The backdrop is a roll of 4-mil translucent polyethylene film, and the angel is supported atop an inverted drinking glass - because improvisation is key to these kinds of projects, right?

I used the Intrepid 4-by-5 (5-by-4 inches in the UK) with the Fujinon 135mm F/5.6 lens, set up atop a Bogen tripod. Wide open at F/5.6 there was inadequate depth-of-focus to bring the figure in sharp relief, but I made a test print anyway, to check my exposure.

Here's the subject focused upon the ground glass, open at F/5.6:

Christmas Angel studio setup

You may be able to tell that the diffusers for my high-tech, $8 hardware store lights are sheets of translucent drafting vellum, clipped onto the lights with bulldog clips. Again, improvisation is key.

I've been working with the direct positive reversal process enough to have confidence with using Arista grade 2 RC paper, purchased from Freestyle Photo. It's a bit harder finding fixed-grade RC coated print paper than multi-contrast papers. Earlier this week, I made a series of tests to see what happens with multigrade RC paper, which I hadn't tried before with this process; Ilford warm tone, to be exact. In daylight, the multi-contrast paper is exceedingly contrasty, almost like lithographic film, not really suitable for continuous tone subjects. I tried filtering the camera lens using contrast control filters, and had a series of "interesting" results, none of which were of sufficient quality to be of use in serious projects. But after those experiments, I went back and tried my trusty grade 2 RC paper, using the same chemistry, with predictably nice results; again confirming my previous experience that fixed-contrast paper seems to work better for me with this process.

People have asked me how I do the reversal process, so here goes. This week I've been using LPD paper developer, mixed 1+4 (50mL concentrate into 200mL water, for a dilution ratio of 1:5). I've had good results with this new developer, and will thus continue to stick with it. For the citric acid solution I mix 4 teaspoons of citric acid powder into 500mL of water. For the H2O2 I mixed fresh 35% H2O2 in a 1 +1 solution with water, for an effective strength of 18%. I get my concentrated, food-grade H2O2 at Moses Kountry Health Food store (it's sold for use in "peroxide therapy"), here in ABQ. Besides some trays of water, I'm also using a mild stop bath, of 500mL water with a "dash" of white vinegar, to render the solution mildly acidic. All of the trays are brought up to room temperature, no small feat considering my garage-based darkroom is nominally around 48f in the winter; I run a space heater in the darkroom, and microwave the chemicals before pouring into trays.

Care must be taken to wear gloves and eye protection when working with concentrated H2O2, and to ensure one doesn't slosh the stuff around when transiting from garage to kitchen microwave.

The subject is metered at ISO3, then I add 3 additional stops of exposure; my meter only goes down to ISO 3, so the effective exposure index would be less than ISO 1. Today's initial test was metered at F/5.6 for 2 seconds, but I gave an extra stop to account for bellows extension, for a final exposure time of 4 seconds. I think this is "short" enough that a portrait could be made under the same conditions, if the subject had a head brace.

Processing was as follows:

First development 2 minutes. The image should look over-exposed, almost completely black.
Rinse/stop for 30 seconds in the mild acid solution, just to stop development.
First citric acid bath for 30 seconds.
First H2O2 bath for 1 minute, face down, continuous agitation. The print should look white with just a few dark areas. Expect plenty of fizzing action.
Repeat the citric acid and H2O2 steps. The print should now look almost completely white, with just a few gray areas. Be careful of peroxide drips contaminating the work area when moving the print from tray-to-tray.
Rinse the print of residual H2O2 in a tray or over running water, to make it safe to handle.
Turn on the white lights. Second exposure for 30 seconds adjacent to a bright white LED bulb. You may begin to see a faint image begin to auto-develop.
Under white lights, place print back into developer tray, face-up, for the second development. Very quickly (<30 seconds) you should see the positive image form on the paper. This is the magic happening.

Permit the print to fully develop for at least 2 minutes, then give an archival rinse. There should be no unexposed silver halides left in the paper, so no need to stop or fix.

For the second exposure, I stopped the lens down to F/16, to give sufficient depth-of-focus to render the angel figure sharply focused. Since F/16 is three stops more than F/5.6, the exposure time was 32 seconds. Processing was the same as previous. It came out nice, I'm very pleased.

Note that with printing paper there's little or no reciprocity failure, since these exposure times are what you'd typically use in the darkroom for printing from negatives. Both prints (4 seconds versus 32 seconds) look identical in terms of exposure.

This batch of H2O2 (diluted 1+1 with water) I poured up yesterday from a fresh bottle, during my struggles with the variable contrast paper tests. But I've saved the older batch of peroxide, which I've been using for the last year (!), as I think it's still usable. It seems to have a very long life, another positive attribute to the process.

I'm finding this process to be less trouble-prone than using Harman Direct Positive paper, which is developed in standard print chemistry (developer, stop bath, fixer). I tried some outdoor tests with the Harman paper earlier this week, with poor results; it requires fresh, strong developer at room temperature, and seems to lose speed in the winter daylight with its lack of strong UV light; it's also very contrasty, whereas the grade 2 paper is much less so. Since either process requires the use of three chemicals (developer, stop bath and fix versus developer, citric acid and H2O2), and I can use a variety of RC papers for the peroxide process (Harman Direct only comes in a fiber paper), I'm finding it more convenient, since RC paper requires much shorter rinse times, and dries flat without curling. Also, the grade 2 RC paper I'm using has a semi-matte finish, a nice surface for a print. And it's quicker than processing paper negatives, then having to contact print a positive (which means running at least one test strip before hand). The only downsides to the direct positive process are you don't have a master negative from which to make more prints, and the exposure times are longer than for paper negatives.

I mentioned previously that I'd been using that older batch of H2O2 (and an older batch of citric acid) for the last year. It's gotten me thinking about residual silver. If you're a darkroom worker, you should know that fixer removes unexposed silver halides from paper and film, which gradually builds up in the solution of used fixer until it's saturated and no longer usable. The exhausted fixer I will turn in to the local hazardous waste disposal site (it shouldn't be poured down the drain, since silver may be considered a heavy metal); although others report success with auto-plating the silver out of solution using fine steel wool.

My question is this: why wasn't I seeing a build-up of residual silver in the used citric acid and/or H2O2 solutions? I've been using the same solutions for over a year; what gives? In a bottle of used fixer it's common to see a dark gray film of oxidized silver build up on the inside surface of the container, but no such film is seen in either solution. I'm guessing here (and I'm not a chemist) that the silver that gets "bleached out" of the paper is in fact still in the paper, it's just bonded with something to render it white (or very light gray) in tone.

Well, that's my report for now. I'm pleased with the final print, and will also be doing more images with the 8-by-10 (10-by-8 inches in the UK) box camera with its F/4.5, 240mm Fujinon Xerox lens.

I wish you all much joy and happiness in the coming year, and thank you for visiting. Please leave a comment below if you have any questions.

Which reminds me, do you have issues with leaving comments here on Blogger? I find on my iOS devices that I have to visit a blog using Private Browsing mode, otherwise Blogger doesn't give me an option to log in when leaving comments on other's Blogger sites. Go figure ...

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Monday, November 25, 2019

Early Thanksgiving

Selfie, Kodak Ektar 127mm on Cameradactyl OG, reversal processed Arista RC grade 2 semi-matte paper
“Early Thanksgiving”

The Cameradactyl OG with Kodak Ektar 127mm F/4.7 lens:

Cameradactyl OG with Kodak Ektar 127mm F/4.7 lens

Rear view showing view screen, 1:1 finder and close-up focusing string:

Cameradactyl OG with Kodak Ektar 127mm F/4.7 lens
The shutter release cable feeds through a hole in the grip. There's also a slot in the grip for a camera strap.

There are three mounting slots for the 1:1 finder, I prefer the middle slot, to reduce parallax error.

The large blue lens mounting ring up front is also the helical focuser. I have lines marked on the focus ring to indicate infinity focus, along with three closer distances, equivalent to three knots tied in the yellow focusing string.

For the self-portrait at the top, I preset the focus ring for the closest position, then placed the first knot of the string against my temple, adjacent to my eye, then stretched the string taught. A 36" shutter release cable permitted me to trigger the shutter from that position. Exposure was metered at ISO 3 + 3 stops, which came to F/5.6 at 1/2 second in bright sun. The direct positive print was processed using the citric acid / hydrogen peroxide method, using the same chemicals I've been using for a few months.

Here's a close-up of the newly acquired Ektar 127mm lens, with the front ring removed to gain access for degreasing and cleaning. I was able to get the speeds back pretty close to normal, but the bulb position still doesn't work; but I can still use a dark slide over the lens while in the preview mode instead.

Kodak Ektar 127mm F/4.7 Shutter

Typecast via Torpedo 18:

Torpedo 18

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Tuesday, November 12, 2019

Direct Positive Color Prints? Yes!

Direct Positive RA4 Color Print by Ethan Moses, exposed using a Cameradactyl 4x5, processed in Dektol, stop bath, color developer and blix.

“Direct Positive Color Prints”

The nice thing about receiving the Cameradactyl Pinholio was that I had the opportunity during last week's visit to choose my color for the pinhole cap (gray), and also to watch his 3D printers begin their slave-like work of printing the parts for the camera.

Cameradactyl Pinholio Self-Developing Pinhole Camera

The Pinholio has an internal pull-shutter, and a removable threaded front pinhole cap. Once the exposure is made, the shutter is closed and the pinhole cap replaced with a 3D-printed, light-proof pour spout, the kind seen on film developing tanks, permitting the paper to be processed within the same camera, out in the field. Since all the parts are made of resilient plastic, exposure to chemicals is no problem.

I hope to soon begin testing the camera, both for exposing and process paper negatives, as well as the peroxide/citric acid reversal process. One caveat with that reversal process is the effective film speed of the paper drops to sub-ISO 1 values, meaning for this pinhole camera with an aperture of F/235 I'm looking at exposure times in bright sun of >10 minutes. Probably too long for seated portraits!

It is for this reason that I'd like to convert (or have Ethan 3D print) a lens cap adapted for a single-element meniscus lens. I've seen a plethora of such lenses available online at places like Surplus Shed. My idea is to build a spacer that fits between the rear flange of the inner box and the rear lip of the front part of the camera, to serve as a focal length extender that would preset the camera for a certain focal range, for use with seated portraits. A fast enough lens should permit exposure times in bright sun of a second or two. Then to be able to process the paper into a unique positive print would be a blast. The inner rear portion of the box slides in and out in a well-designed light trap slot that seems near ideally suited for focus adjustments. Since the intended design holds the paper tight against the rear of the camera by the two box halves completely closed, I'd use a loop of masking tape on the reverse side of the paper, since I'd be extending the box for focusing.

With a changing bag, a person could use this handheld "Afghan Box Camera" for making portraits in public. I'll keep this blog updated with progress.

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