510 pyro update

[mike_barger]

<p>I've just gone through Fred Picker's film speed test, development test, and the proper proof test.<br /> I use HP5 in 4x5, Dektol 1:2 (two minutes), and 510 Pyro 1:100 (70 degrees). I develop in an old Jobo 4323 drum with the (I think) 2120 reels. This rolls on a unicolor base with the auto forward reverse. Paper is MCP 310. The new Adox RC paper.<br>

The tests led to a rating of 200 for the HP5 (same I get for HC110) and a development time of 17 minutes. Fred's test for time of development is based on printing a zone VIII negative for the minimum time to produce max back on the paper.<br>

I know the is a lot longer than Jay's time for continuous agitation. As a further test, I followed up with a different batch of 510 pyro from Artcraft, but the test results are the same.<br>

Not complaining, I love the results. I was just wondering if anyone else was using a longer development time?<br>

Mike</p>

[mike_barger]

<p>As a side note, I do get full speed from Tri-X 400 in 120.<br>

Mike</p>

[trooper]

<p>This was the EI that I ended up at when I was dealing with 510 and HP5+. I never did try it on Tri-X, though. I keep hearing good things about the paper.... I'll need to try some. Thanks for the report.</p>

[jay_de_fehr]

<p>510-Pyro 1:100/ HP5+/ 17min/ 70F/ rotary agitation should produce gamma infinity, or very close to it. I think the discrepancy can be traced to at least two sources: 1) Picker's methodology, and 2) the printing characteristics of stained negatives on VC paper. These factors combined could lead to this kind of gross error, and it definitely is an error, both in film speed determination and normal development time. If you're trying to print a stained negative on VC paper without filtration to calibrate film development, you're trying to hit a moving target, and the target won't stop moving until the paper runs out of latitude at grade 0 or 00. You're much better off using graded paper for these kinds of tests. </p>

[mike_barger]

<p>Jay<br>

The film speed part of Picker's test doesn't involve paper. The base plus fog of a unexposed and developed negative is determined. Then I made zone I negatives at 100%, 75%, 50% and 25% of the box speed (400 in the case of HP5). The negative showing between .08 and .10 is the negative Fred indicates is correct. I've run this test twice and HP5 has came in at 200 both times.<br>

When I've tried the same test on Tri-X 400 (120mm) in comes in right on the button at 400. Both films I used a calibrated X-rite 810 to measure the base plus fog negative and the zone I negatives.<br>

This seems to be a pretty common test method to determine an individual EI. Does it not work with 510 pyro?<br>

Fred's development time test involves finding minimum exposure through the base plus fog negative on the same paper you plan to print on. For me that is MCP 310 RC VC Adox (and some MCC110 that will require an additional test). The time I came up with on this part of the test was (7) 3 sec bursts @ F22. <br>

Then shooting zone VIII negatives ( I shot a medium gray card 16X20 taped to my garage door in the shade), I tried 7.5 minutes (with the method in the OP) and the print was much to dark for zone VIII. I extended development times until the zone VIII printed with a slight change to gray from the white paper base. That time ended up being 17 minutes. The mix of the 510 was 10 ML of 510 and water added to make 1100ML @ 70 degrees.<br>

As I understand your response I should have used graded paper to determine my proper development time (and film speed?). Are you saying run the same test as described, but use a grade 2 paper?<br>

The part I really didn't understand (I have very limited darkroom experience) is how the VC paper will be a moving target from grade 2 to grade 0 if I don't add filtration during the test?<br>

The other question I have, if I test to a graded paper but only use Adox MCC110 VC fiber or Adox MCP310, how is the test relevant to the paper I will be using?<br>

Looking for suggestions.<br>

Thanks for reviewing.<br>

Mike</p>

[mike_barger]

<p>This a print from the testing. There is more detail in the white (center) than scan shows.</p>

<p><img src="http://www.photo.net/photodb/member-photos?user_id=22102" alt="" /></p><div></div>

[mike_barger]

<p>I also should add, it looks like one of the photography chemical vendors is looking at selling 510 Pyro mixed.</p>

<p>I should be receiving some of the first trial batch to test in two weeks. I hope it works out.</p>

<p>Mike</p>

[jay_de_fehr]

<p>

<p>Hi Mike,</p>

<p>Have you ever posted a message and then read it later, and been shocked at your tone? I hope I didn't seem as curmudgeonly to you as I seem to myself, reading my post from yesterday. Sometimes I try to post when I don't have time, and end up being too short, and I can seem harsh, I think. I'm sorry if I seem so to you. </p>

<p>The film speed test:</p>

<p>Picker's method is not a precise one, relying on in-camera exposures, so 1 stop discrepancies are quite common. My testing is done much like the manufacturers' testing is- film exposed in a sensitometer, developed in an automated processor, and measured with a calibrated densitometer. Even here, stained negatives demand some deviation, and should be read in the blue channel, as if the negative would be printed on graded silver paper, for either graded or VC papers, and in UV channel if it is to be printed by a UV process. My negatives are 21 step wedges, and once read, the characteristic curves are plotted in Winplotter, and the speed and contrast values calculated. By this method, the camera, lens and shutter are eliminated as variables, the negative stain is taken into account, and film speed is tied to contrast. </p>

<p>Film development test:</p>

<p>This is where things really go astray.When you test to find minumum exposure through the base plus fog of the negative, this negative has very little density, and almost no stain, so with your VC paper, you're testing at the equivalent of Grade 2. Your Zone 8 negative is a contrast filter when printed on VC paper, and since stain density is proportional to image density, a Zone 8 negative is a fairly dense yellow filter. So, you're essentially testing for minimum exposure for a Grade 2 paper, and a development time for a negative to be printed on grade 0-00 paper.These grades of paper can have Exposure Ranges of 2.0, or more, and require very high contrast negatives, which explains your extraordinarily long development time. In short, your testing methods are incompatible with stained negatives to be printed on VC paper. </p>

<p>I think your image above is a testament to the abuse this film/developer combination can endure! I'm sure there's TONS of shadow detail in that negative! For an idea of what I'm trying to describe above, you should print the same negative on grade 2 graded paper. </p>

<p>I'm surprised, and a little disappointed that a manufacturer planning to offer 510-Pyro for sale didn't contact me, and offer a sample for me to test. </p>

<p> </p>

</p>

[mike_barger]

<p>Did you get the note I sent you? They are very interested in having you test.<br>

My email is<br>

bargerm@gmail.com<br>

I don't want post their name, but I will email you the information. I was involved just trying to find another vendor to make kits. The last couple times Artcraft didn't seem to interested in making individual kits, but they did.<br>

When I told this vendor what I wanted (baggies like Artcraft makes) on Friday they said sure thing. Then they called me back Saturday morning and said they were interested in making it to sell ready made. I told them I would contact you and give you their contact info.<br>

I used the send a message to a member here, maybe it didn't work. Would have been this past Saturday.<br>

Based on your first post, I decided to shoot two scenes (two negatives ea) and develop one for the 8 minutes and one 17. As you can guess a big difference. I'm going to print them tonight on the Adox paper and see what I can do. I couldn't get away from the fact I was doing exactly what Picker instructed, vs. your knowledge base of this developer. So I decided to reshoot, and develop (yesterday afternoon) and print tonight. I must say the 8 minute negatives look better to the eye, other is pretty dense.<br>

Your 510 buddy<br>

Mike</p>

[jay_de_fehr]

<p>

 

<p>Hi Mike,<br />I'm sorry I didn't get your email; I rarely check that old email account. You can contact me at:<br />jdefehr@gmail.com<br />Printing stained negatives on VC papers is a complicated subject, and calibrating film development backwards from the printing paper, even more so. I started writing an article on the subject a while back, and I've gathered so much data/ material, it's beginning to look like a book, instead. The short of it is: use graded paper for this kind of calibration, and your results will be transferable to VC papers. I think you can expect to see a real improvement in the printing qualities of your negatives, especially in smaller formats, which don't tolerate over development nearly as well as larger formats do. If you don't have any graded paper, a rough workaround is to <strong>add magenta filtration until the image on the easel doesn't look yellow/green/brown</strong>. Placing a piece of white paper in the easel will make this evaluation easier. This is the neutral point. If your negative requires more contrast, add magenta filtration; if it requires less contrast, reduce magenta filtration. Give this a try with your 8 min neg, and see how it works for you.<br />I hope I haven't confused or overwhelmed you with a lot of advice that might seem arbitrary or contradictory. Once you wrap your head around the concepts, it will all make perfect sense. In the meantime, my advice above should save you a lot of frustration. Have fun, and post your results; we all learn something from your posts.</p>

 

 

 

</p>

[jay_de_fehr]

<p>Mike,</p>

<p>I was looking through some files, and I found the following excerpt from a posting on this or another site:</p>

<p>"I have been using 510 pyro for over a year myself and am very pleased with it. HP5, FP4 and Tmax 100 are the films that I have used. I have also noted that development times for variable contrast paper are longer than other published results-7.5 to 8 minutes for HP5 for example. Printing on graded paper at these times, however, will give way too much contrast and the published times of around 6.5 min seem more appropriate for this. So, I think one has to plan on what type of paper is going to be used to determine the correct developing time. "<br>

I think John Bond is the author. It's from a file marked, "510-Pyro '07", so I assume it's from around that time. The above is one of many excerpts I collected when I began investigating the special relationship between stained negatives and VC papers, and one of the most concise. <br>

Virtually every time someone reports very long developing times for 510-Pyro, they are printing on VC paper. So, you're not alone Mike! Worse than a lack of information, there is a glut of bad information on this subject, espoused by so-called "experts", who. lacking a fundamental grasp of the principles at work, advocate gross over development as good practice. It's diabolical!</p>

[kevin_thompson3]

<p>Jay, what dilution, temperature and times do you suggest for developing FP4 Plus, HP5 Plus and TMY2 for printing on grade 2 Ilford Galerie paper and what did you find the effective exposure index to be with those films in 510 Pyro? This would be for use with a diffuser enlarger with white-light. (No VC filters).<br /> I am interested in trying your developer formula soon.</p>

[jay_de_fehr]

<p>

<p>Hi Kevin,<br>

I'm not at home, and don't have access to my data, so I can only suggest ballpark figures. Using a 1:100 (1+99) dilution, at 70F, with rotary agitation, for printing on G2 paper, TMY-2 and FP4+ should develop a scene of normal contrast in the 5:30-6:30 range, and HP5+ in the 6:00-7:00 range. All of these films can be exposed at box speed. TMY-2 and FP4+ test a little higher than box speed, and HP5+ a little lower, but not significantly so. 510-Pyro contains no sequestering agents, so water quality could impact development times. My results using my tap water don't diverge from my results using distilled water, but water quality can vary considerably, and it could, theoretically, affect development times. If you suspect your water quality, you could run a test by developing a control film in distilled water to compare to a test film developed in your tap water. The times given above should provide an adequate starting point for your personal testing. Good luck, and let me know if you have any other questions. You can contact me at:<br>

jdefehr@gmail.com<br>

Or by posting your questions at the <a rel="nofollow" href="http://pyrostains.blogspot.com/" target="_blank">510-Pyro blog</a>.</p>

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