Monday, October 07, 2019

Overdue Update

1962 Torpedo De Luxe
Recently acquired 1962 Torpedo De Luxe, featuring the wonky 5 & 6 keycaps, and decades of grime.

“Overdue Update”

I've been tinkering some more with the citric acid / hydrogen peroxide reversal process for direct-positive prints from silver gelatin photo paper exposed in-camera. Here's a recent still-life.

Owl, Citric Acid + H2O2 Reversal Process, Fujinon 135mm @ F/5.6, 45 second exposure, 4x5 format Arista RC grade 2 paper

I've found better results by processing the print face-down in the citric acid and peroxide bleaching solutions, and also do two passes, before the second exposure and development.

While up till today all of my reversal tests have been under shaded daylight, the multi-seconds-long exposure times were not compatible with the possibility of seated portraits. So today I made a series of test exposures in the bright morning sun of my front patio, with Your's Truly as subject. For focus I used a test card tied to the camera with a string. I use a yard stick to stretch the target out in front of the camera until the string is taught, then focus the camera on the target. Then I approximate the composition, based on my experience, and once the exposure is determined via light meter and set on the lens, I sit down in front of the camera, long shutter release cable in one hand and focus target in the other. I assume my pose, bring the target up to my temple and adjust my fore-aft seating position to tighten the string; then slowly lower my arm and trip the shutter.

I thought the results were rather fair, given the harsh light; and the 1/2 second exposure time at F/5.6 was quite adequate for seated portraits.

Self-Portrait, grade 2 RC paper, direct reversal using citric acid + H2O2 process, 1/2 second exposure at F/5.6

I have the 8x10 sliding box camera, currently fitted with a Fujinon Xerox machine lens, 240mm at a fixed F/4.5 aperture. Fast glass, but no possibility of a variable aperture. And the box camera is fixed at a landscape orientation, whereas I'd like to use it for portraits. Perhaps I can rebuild the camera so the cross-section is square instead of rectangular, and the sliding rear portion could therefore be inserted into the front half in either orientation - dark slide facing to the right for landscape orientation, or facing up for portraits. Of course, for accurate exposures with sub-1 second times I can't rely on the accuracy of a lens cap shutter, so perhaps an ND filter can lengthen the exposure times to around 1 second in bright sun - long enough to be timed accurately by hand, while short enough to reduce the chance of motion blur. Always another project!

I'm still using the same batch of citric acid and H2O2, so I don't know how long I can go before they expire. Thus far it's proven to be a very economical process, as long as I ensure consistency in everything I do.

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Blogger SteveK said...

Interesting to hear your thoughts on the mini-wedges. There also Epson and Casios to be found. I've noted in several of my blog posted that the design and quality of daisy wheel machines declined after the mid-1980s - especially the "personal" ones, and then plummeted to new lows in the 1990s (high-spec office machines excepted) ;)

10:46 PM  
Anonymous JeanB said...

One thing I can't get used to with my thermal Canon Typestar 5 is that it stops printing when the carrier reaches the right margin, even when Automatic Carrier Return is enabled. That's unlike most electronic typewriters that will keep printing past the margin, and then return, so one can type away without interruption. I wish I could enforce that. Maybe you know how?

5:56 AM  
Blogger Bill M said...

The plastic gears are why I mostly steer clear of electrics and thermals although I do have an EP-20 to play with. There are plenty of small gear suppliers, but finding one with a metal gear with the needed requirements is not easily done.

I also have problems commenting on blogs. If the comment posts - good. If not I still have read the blog. Word Press is worse for me than Blogger.

One year I hope to get to the balloon festival. Whenever I used to visit date was never near enough to the festival or I'd have stayed (if I could have found accommodations).

Can't wait to see the finished Torpedo.

Thanks for the tips on processing.

7:56 AM  
Blogger Joe V said...

Jean, you have to type a space or hyphen once in the “hot zone” near the right margin, then it’ll do the carriage return. But if you fill up the hot zone with other characters it’ll just come to the end of the line and beep. Also, it helps to set the right margin a bit in from the physical right most end of the carriage.

10:33 PM  
Blogger Mike A. said...

Mornin’ Joe. Sorry to here your woes with the thermals. I suspect mine will hit a wall at some point and it will be off to a recycler. Sad state of modern technology is that is was built to throw away. It’s funny when you think about it, but typewriters will probably outlast modern technology.

As for commenting to Blogger via Safari, I find that right about the time I figure out a solution, Apple/Google start scrapping and the solution fails. My solution is to play both sides of the fence. I comment in the Notes app, open Chrome on my iPad/iPhone and copy/past the comment to Blogger. It’s a bit of a hassle, but it works.

5:27 AM  
Blogger Mary E said...

Good to hear that the platen on the Torpedo is fairly easy to take out - I have a twin sister to yours with a wonky replacement key top (looks like someone pulled it off an adding machine) and a rock hard platen. The Torpedo is a one of my very best typewriters, but I rarely use it because it's so, so loud and I was hesitant to take out the platen.

7:36 AM  
Blogger Ted said...

Sorry to hear your thermal mini-wedges are dying - at least they're cheap enough to replace easily. (:
I'm really enjoying your video series on the reversal print process - I think you're getting great results! :D

9:37 PM  
Blogger Ned said...

Hi Joe! ( No need to post this comment or anything )... just stumbled by your blog, the 3-D printed develop-in-camera caught my eye and I've got to tell you I laughed out loud and said "of course!" when I saw monobath! Brilliant. Do you remember the fellow at F295 who made those beautiful ceramic pinhole cameras, each one was a work of art. Ever since I saw those I've been thinking of making one where development could be done inside the camera.

Then I scrolled down and saw that direct positive color post and I absolutely have to try that. I love my little instant film pinhole camera for color but 8x10 direct positive would be fantastic... I wonder how slow it would end up being with those filters.... anyway, thought I'd say "hi" and merry christmas and hope all's going well with you. See you over at photrio sometime... cheers! Ned

9:03 PM  

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