you can get both...Originally Posted by IanBarber
Fomaspeed Variant RC
you can get both...
Fomaspeed Variant RC
P1030658a by Joe Van Cleave, on Flickr
Grade 2 RC paper, pre-flashed, Intrepid 4x5, Fujinon 135/5.6 lens. Rio Grande north of Albuquerque.
The photograph and the thing being photographed are not the same thing.
Nice work Joe, is that reversal, scan or what?
From reading just now, your 'Typewriter' review and the recon report I figure it's a contact print. Good writing too!
Randy, this was rephotographed using a Panasonic m4/3 with the negative in a 4x5 enlarger Negative carrier and copy stand LED lights, then inverted and adjusted in SilkyPix. The Panasonic camera was handheld with OIS turned on. The result is better than what I've gotten with an Epson flatbed scanner.
The photograph and the thing being photographed are not the same thing.
Looks good and I would never have guessed all that!
Agfa Brovira 3
fkd 5x7 + industar-51
Lorelai Blue by Jukka, on Flickr
Hi Tony and Ian,
I did some quite extensive testing a few years ago of VC paper that was developed to completion (i.e. not pulled early from the developer) under a wide range of lighting conditions, so that I could use paper negatives for pinhole as well as in my view cameras. For pinhole, the reciprocity failure has to be accounted for, so I wanted to work out a compensation equation; I also tried using flash. I also use graded paper, and there I have had good success in 'over exposing' by a few stops but then pulling the print early in development; the reciprocity behaviour and 'base ISO' of the VC paper seems quite similar for the graded papers I have when dev to completion, but I guess there may be more variability with grade and brand. I usually use VC and development to completion now though as it means I can develop negatives in tubes rather than trays.
For the development to completion process with Ilford MGIV VC paper (I have had very similar results with a VC Fotospeed paper too), I use Fotospeed PD5 paper developer at the normal 1+9 dilution and develop fully at about 20 degrees Centigrade (well, between 10 degrees to 26 degrees so far with no dreadful changes in the negs); I have found sometimes trying to pull a VC negative early can risk a 'mottled' effect on the print that seems to be some form of uneven development, so I only run to completion now. I have used a few other developers too, and as long as you leave them go to completion, they have all worked fine. I choose my paper rating based on the dynamic range of the scene (lightest to darkest tone), usually measured using my compact digital camera as a light meter, and have the option of shooting with or without a yellow filter as the VC paper has a fast layer that responds to blue, and a slower layer that responds to green light. With the response of the VC paper towards the blue/green end, the effective speed can vary a bit too depending on the colour of the objects you are shooting which is an added 'feature'. To help prevent loss of shadow detail, I always pre-flash my paper now and the details below assume the paper is pre-flashed. I pre-flash so that the paper will go *just* off-white when developed, the preflashed paper seems to store for months with no degradation of the pre-flash effect, so I flash a decent batch of paper at a time.
In daylight on pre-flashed Ilford MGIV VC paper with no lens filters, I shoot treating the paper speed as an equivalent of ISO 20, and get +/- 2 1/2 stops of usable range (5 stop total range of tones). With a yellow filter (e.g. Cokin 001) in front of the lens (or behind the pinhole depending on the camera) so that only the green layer of the VC paper is active, I rate the paper at ISO 6 and get +/- 4 stops of range, going quite non-linear in the highlights. The yellow filter is great as I can capture both shadow detail and clouds in the one shot. For incandescent light, reduce the equivalent ISO by a further 1 1/2 stops; the dynamic range will also increase a little to +/- 4 1/2 stops if you use a yellow filter too as there is very little blue content to excite the faster layer in the variable contrast paper. If you want more startling effects, do not flash the paper and in daylight try ISO 8 (with yellow filter), but be prepared for only +/- 2 stops of dynamic range and shadows/ highlights that clip really fast.
For pinhole, the reciprocity failure can be very significant. I spent many hours of swearing developing an equation to allow me to adjust the times; I have tested it with a 7 hour exposure and it is not perfect, but close enough. As reciprocity failure becomes significant, the negatives also get more contrasty as the dynamic range reduces. The correction I use is described by the equation:
t_s = t_c + 0.0009 ( t_c^2.2304)
where t_c is the time in seconds that the exposure table says you should use, and t_s is the exposure time you should actually give the paper. For t_c = 8 seconds (or less), you can assume that there is no failure. At t_c=16 seconds, the equation says use t_s = 16.4 seconds; near enough. for a t_c = 60 sec, t_s = 68 seconds, so no real issues. However the failure effect appears rapidly, so at t_c= 16 minutes, t_s=83 minutes(over an hour!).
For really bright conditions and a lensed camera, I have found shutter speeds to 1/100 sec work fine with rating the paper as ISO 6 (or 20 if no yellow filter), but there is a bit of "reciprocity failure" that starts to be noticeable again from about 1/250 of a second and faster; and the apparent reciprocity failure is pretty bad at the speeds you get with a flashgun so the negative is much thinner than you may initially expect. Different flashguns seem to 'pop' for different lengths of time, and the variability in time seems to be a key important factor; flash power control is achieved by quenching the light output early of course that complicates measurements further. Of the flashguns I tried (set to manual flash, not auto and with 'equivalent' GN setup), the one with the really short bright flash gave a much thinner negative than the one with the longer not-so-bright output; but unless you have the kit to measure the length of the flash output time, it is not easy to tell by eye what your flash is actually doing.
Evan
Computer Parts and an old Typewriter. Taken with a Gundlach Radar Extreme Wide Angle Anast. 8x10 6 1/4 inch (159mm) F16 , 4 minute exposure
Questions and comments are always welcome
Chamonix 10x8, Schneider-Kreuznach Symmar-S 360mm/f6.8 @ f6.8, 1/8 second, one Impact strobe, Galaxy Hyperspeed paper at ISO 50, pre-flashed though plain printer paper (same exposure as for taking), Ilford MG developer, Epson V850 scan:
Thomas 10x8 by chrism229, on Flickr
Chris
This is quite wonderful Chris - when you pre-flash thru printer paper, do you just hold the printer paper against the lens for the pre-exposure?
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