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  1. #61
    Joe VanCleave's Avatar
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    Hopefully I'll have time this weekend to try the yellow filter with the Efke paper. But from my experience with non-reversal paper negatives, I don't think this is a phenomenon that can be fixed with a filter like excess contrast can. I think it's a different problem than the blue/UV of landscape light activating the high-contrast portion of a VC emulsion, which is what the yellow filter helps, by limiting the amount of blue/UV that gets to the paper.

    I don't know in detail how this reversal paper works chemically, but there appears to be two different processes happening simultaneously during development, which is that as the emulsion's shadow details begin to turn dark, the highlights are held back; but it appears that these two phenomenon (layers?) have different reciprocity failure characteristics, causing the shadow density and highlight density to vary all over the map, based on variations in exposure time; variations that are well within normal film reciprocity ranges, and certainly much more reciprocity failure than I've ever seen in a paper-based emulsion before.

    It reminds me somewhat of color film, where the three dye layers have different reciprocity failure characteristics causing, for example, a blue shift when doing extremely long exposures, because that one layer has better reciprocity linearity than do the other layers.

    My initial success with the Efke paper is based on the strategy of calibrating one's process to a single, fixed standard exposure time, and varying the subject illumination and/or f-stop to accommadate the scene's actual brightness to the paper.

    ~Joe

  2. #62

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    Quote Originally Posted by Joe VanCleave View Post

    My initial success with the Efke paper is based on the strategy of calibrating one's process to a single, fixed standard exposure time, and varying the subject illumination and/or f-stop to accommadate the scene's actual brightness to the paper.

    ~Joe
    Oh dear...that is the opposite of what most pinhole users will be able to achieve. If outdoors you have very limited control on illumination and unless you are a 'hi-tech' pinholer with a turret of options, length of exposure is about the only control you have.

    My box is on the way, based on your experience I think I'll give pinhole photography a miss for the time being! I'm going to try and get to grips with it in some old plate cameras, I hope it arrives for the weekend, it is bank holiday over here, so 3 days to play
    Steve

  3. #63
    masimix's Avatar
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    What kind of developer does one need for this paper?

    edit: just found the factsheet http://www.ilfordphoto.com/Webfiles/...1151622042.pdf where it says one can use Ilford Multigrade

  4. #64
    RalphLambrecht's Avatar
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    Quote Originally Posted by Joe VanCleave View Post
    Hopefully I'll have time this weekend to try the yellow filter with the Efke paper. But from my experience with non-reversal paper negatives, I don't think this is a phenomenon that can be fixed with a filter like excess contrast can. I think it's a different problem than the blue/UV of landscape light activating the high-contrast portion of a VC emulsion, which is what the yellow filter helps, by limiting the amount of blue/UV that gets to the paper...
    Yes, that's exactly it. The yellow filter works well with VC papers and doesn't do much for direct-positive papers.
    Regards

    Ralph W. Lambrecht
    www.darkroomagic.comrorrlambrec@ymail.com[/URL]
    www.waybeyondmonochrome.com

  5. #65
    RalphLambrecht's Avatar
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    Quote Originally Posted by masimix View Post
    What kind of developer does one need for this paper?

    edit: just found the factsheet http://www.ilfordphoto.com/Webfiles/...1151622042.pdf where it says one can use Ilford Multigrade
    I've used Agfa Neutol WA, but I'm sure it works with many developers.
    Regards

    Ralph W. Lambrecht
    www.darkroomagic.comrorrlambrec@ymail.com[/URL]
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  6. #66
    Joe VanCleave's Avatar
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    Quote Originally Posted by steven_e007 View Post
    Oh dear...that is the opposite of what most pinhole users will be able to achieve. If outdoors you have very limited control on illumination and unless you are a 'hi-tech' pinholer with a turret of options, length of exposure is about the only control you have.

    My box is on the way, based on your experience I think I'll give pinhole photography a miss for the time being! I'm going to try and get to grips with it in some old plate cameras, I hope it arrives for the weekend, it is bank holiday over here, so 3 days to play

    It may not be as bad as I'm suggesting.

    One thing I've done with regular paper negatives with pinhole cameras is to calibrate an exposure time for each camera/focal ratio and lighting condition, one in direct sun and another in cloudy daylight. Rather than using calculators and reciprocity charts, I will impirically test for these two light conditions, setting up the darkroom in the daytime and doing a series of exposures in my sunny backyard and shaded porch, for instance. As an example, using my paper, developer and dilution combination, camera X may have a bright sunny exposure time of 45 seconds and a cloudy daylight exposure time of 2 minutes. With regular paper it's pretty easy because its reciprocity characteristics are rather linear out to at least 5 minutes, perhaps longer. Paper gets wiggy with color temperature, like incandescent, which lacks blue/UV, and hence needs more exposure than you'd otherwise suspect.

    This same testing methodology might work with the direct positive paper, you just have to arrive at the right combination of preflash and in-camera exposures for each of the major kinds of light level you expect to encounter (direct sun and shaded daylight, for instance). Also, having some calibration on artificial lighting for a still-life composition might also be helpful.

    I still think this paper is useful for pinhole cameras, you just have to do more testing and document your results, referencing your meter's reading with your test results for that light level.

    ~Joe

  7. #67

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    My packet of paper arrived Friday

    I have spent the weekend experimenting with this paper.

    One of the first things I tested was my safe-lights. I found that, despite being 'red' and safe for every other paper I have ever used (except Kodak Panalure, obviously) they are definitely not safe for Harman Direct Positive paper!

    A Photax dome type "A" with a 15 watt bulb over four feet away shows visible fogging effect after 30 seconds. I've posted a few test strips I made in the technical gallery. The Ilford recommendation is a '906' filter. I don't know what this is, but it is clearly a much deeper red than my standard darkroom lights. I'm going to try taping a wratten 29 (ruby red) filter over a torch, later today, I'll report back.

    The surface of the paper is very pink! My first few test strips came out as black and pink images... my initial reaction was to increase fixing time and agitation, which made no difference. Extended washing is what it needed. The Ilford Technical Information recommends 60 minutes for fibre based paper, which would no doubt take care of it, but I have the RC version, so expected a much quicker wash (I'm only doing test shots, so I'm not interested in archival quality). Well... a quick wash does NOT do the trick.

    I used the paper in various plate cameras, mostly quarter plate. I standardised on an exposure of 2 seconds (following Joe VanCleave's advice - I'll worry about reciprocity later...) and a development time of 2 minutes in Ilford Multigrade developer. The weather has been a bit miserable - cloudy and overcast. Consequently the scenes I photographed were very flat, low contrast with no shadows. EV values were around 10 to 12 so I was mostly using f11 and f16.

    My first few images, without pre-flash, had very hard soot and whitewash type contrast. I made a lot of test strips to find a pre-flash time that would give just give a noticeable change in density (no longer fully black) then backed off a little. On my set up this meant 6 seconds on an Opemus 6, 75w lamp, 40 cm above the baseboard, no filter, f22. This gave a focussed image of 14" X 14" (I defocussed it to make the flash).

    The result was a dramatic change in density - at the expense that nothing in the picture was fully black any more. Consequently it was all a bit muddy. I reckon the paper speed comes out at about ISO 6. Later shots I halved the pre-flash. This allowed me to produce black again, but the contrast again became very harsh and the I reckon the image was about a stop under-exposed (down to about ISO 3).

    Next I tried a soft working developer. I mixed up some Ilford ID3 - which is very close to Kodak D165. This tamed the contrast, but only by preventing the paper from producing a proper black, as with the max pre-flash. The edges of the print, where the paper was unexposed, were a couple of zones short of true black. I then tried 30 seconds in Ilford multigrade developer, followed by 90 seconds in ID3. This got back my black edges - but the print was still a bit muddy with no true blacks in the image. Much work to do, yet!

    So-conclusions so far:

    1. Standard red darkroom lights are not safe.
    2. The paper does respond to different developers to control contrast.
    3. Pre-flashing also controls contrast, but I haven't yet managed to get a satisfactory print using pre-flash and full development in Multigrade developer. Sufficient pre-flash to get the contrast into a suitable range prevents the formation of a true black.
    4. Paper speed approaches ISO 6 with a max pre-flash (just short of recording a tone) , ISO 3 with half that value.

    I've posted some images in the technical gallery.
    Steve

  8. #68
    Marco B's Avatar
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    Quote Originally Posted by steven_e007 View Post
    Much work to do, yet!

    So-conclusions so far:

    1. Standard red darkroom lights are not safe.
    2. The paper does respond to different developers to control contrast.
    3. Pre-flashing also controls contrast, but I haven't yet managed to get a satisfactory print using pre-flash and full development in Multigrade developer. Sufficient pre-flash to get the contrast into a suitable range prevents the formation of a true black.
    4. Paper speed approaches ISO 6 with a max pre-flash (just short of recording a tone) , ISO 3 with half that value.

    I've posted some images in the technical gallery.
    Would it possibly be of any use to contact Susanna Kraus to ask what she does to get her images developed properly? As we now know, thanks to Simon's post, that this paper was actually developed specifically for use with her life-size IMAGO camera... I don't see any of the excessive contrast in her pictures, but of course, there is the advantage of the controlled soft-box flash exposure in her IMAGO camera.

    http://www.ilfordphoto.com/pressroom/article.asp?n=128

    Also see the IMAGO links here:

    http://www.apug.org/forums/video.php

    Marco
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    "The nineteenth century began by believing that what was reasonable was true, and it wound up by believing that what it saw a photograph of, was true." - William M. Ivins Jr.

    "I don't know, maybe we should disinvent color, and we could just shoot Black & White." - David Burnett in 1978

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  9. #69
    Leon's Avatar
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    Quote Originally Posted by steven_e007 View Post
    My packet of paper arrived Friday

    The surface of the paper is very pink! My first few test strips came out as black and pink images... my initial reaction was to increase fixing time and agitation, which made no difference. Extended washing is what it needed. The Ilford Technical Information recommends 60 minutes for fibre based paper, which would no doubt take care of it, but I have the RC version, so expected a much quicker wash (I'm only doing test shots, so I'm not interested in archival quality). Well... a quick wash does NOT do the trick.

    Stephen - I havent noticed the pink at all. I've been using the FB version in my 5x4 camera, deving it in neutol at 1:11 and stop bath in the dark, then lights on after 30 seconds in the stop (ilford rapid 1:7) no pink at all.

    I'm noticing exactly what others have said about the Efke paper and short exposure reciprocity. Anything shorter than 1 seconds is useless. I'm also noticing an inconsistency in shots using the same light conditions, exposure, development routine etc. It's a tricky beast for sure.

  10. #70
    David A. Goldfarb's Avatar
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    The Imago camera uses strobes, so short exposures are certainly possible with testing, but the advantage of the Imago camera is that every exposure is the same, since the flash-to-subject distance never changes. It's sounding like whatever one does, it's probably best to test at two or three different exposure times and use aperture or lighting to control the exposure.

    I've contacted Harman about ordering some.
    flickr--http://www.flickr.com/photos/davidagoldfarb/
    Photography (not as up to date as the flickr site)--http://www.davidagoldfarb.com/photo
    Academic (Slavic and Comparative Literature)--http://www.davidagoldfarb.com



 

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