zarrir_junior

<p>James, you are correct, TEA stands for Triethanolamine. Triethylamine is a different animal. Jay, that mixture would be just an experience, not intended to overcome the well-known and remarkable 510-Pyro formula.</p>

<p>Actually the answer couldn´t be easier: If i cool the solution to 10 degrees Celsius and it freezes then it is a non-LFG TEA</p>

<p>Apparently, the final destination of this specific product would be the cosmetic industry. Any clues? Is there any test i could do on that solution to try to identify DEA there? Either way, specially because it does not hurt, i will try to develop one roll with a 510-Pyro from that TEA and i will also experiment with a 50% TEA-DEA solution to see what happens.</p>

<p>Hmmmm, i bought it locally and my source could only specify 85% Trietanolamine. He also does not know if it is LFG or not. I have compared it to a 98% DEA solution and it looks definitely more fluid. I guess i bought TEA LFG.... :-((</p>

<p>Is there any inconvenience in using 85% TEA instead of 99% TEA when mixing 510-Pyro? How about adding some glycol to the stock undiluted solution? How much?</p>

<p>Interesting! I got some very nice 8x10 prints from those underdeveloped medium format negatives! Most were printed at 4.5 or 5 grade filtration to compensate for them being flat, F11 on my dichroic enlarger, 13 sec exposure average, MGIV Ilford paper. I will now continue with my tests with the developer, with and without phenidone to see what i come up with. You should try it Jay. Tone gradation looks better than prints made from properly Pyrocat-M developed negatives and shot at the same light conditions of those (slightly underexposed).</p>

<p>Excellent, thanks for the samples!</p>

<p>What is the effect i should expect if i selenium tone a stained pyro negative? I have lots of selenium in stock and i´m thinking of doing that for archival purposes.</p>

<p>Hi Jay, a little misunderstanding here. The image i posted is a DEA-PYRO developed negative. It is not a Hypercat one. I remember you first suggested a single solution formula with ASCORBIC ACID, CATECHOL AND DEA. This was the one i used. You later suggested that i could simply replace the TEA with DEA in the 510-Pyro to obtain something similar to WD2D. I have not tried this yet. Yesterday i contact printed these negatives and the little prints are obviously too dark. I then set everything up to enlarge this specific image when my enlarger lamp went belly up. I was focusing the negative at that point. I could definitely notice that the grains are so smaller and much more scattered (sparse) than i am used to see. Does that ring a bell with DEA being a silver solvent?</p>

<p>By the way, if this is image stain, then i will probably have to use some yellow filtering when printing... :-) .</p>

<p>Hi Jay, i will make some prints tonight to see how they behave on paper. The negatives were probably 1/2 to 1 stop under exposed. They look slightly grainier than the ones developed in WD2D. I will probably try 9:30 minutes development next time. I used 1:100 dilution as per your recommendation and fixed with fresh TF3 for 3 minutes after a 3 minute water bath (no acid stop). I think you may be right about the residual anti halation dye because i have seen this strong purple tint before with D76 and Ilford FP4 although it looked much more pink than this odd purple. Film markings on the edge are only slightly faded. Would you like me to scan the negative as a positive and post the image here? I am tempted to add a pinch of metol for next roll...</p>

<p>For those interested, bellow is the link to one of the pictures developed with the DEA formula above. Ilford FP4+ roll film 125, developed 7:30 minutes, 20Celsius, Jobo slowest speed. Negatives turned out kind of thin with a strong overall purple tint. The bellow scan was the best one i could pick.<br>

<a href="../photo/11986951">http://www.photo.net/photo/11986951</a></p>

<p>Thanks Chris!</p>

<p>Just confirming Wendell´s experience above i see no dichroic fog on the prints i´ve done last week (about 100) when using three 30 seconds water rinses between the developer and TF4. So i see no reason (at this moment) to use an acid stop with my Jobo prints. What pleases me most is the fact that by doing this i am avoiding chemical contamination in my system, keeping it alkaline all the way. No acid spills anywhere.</p>

<p>Thank you Edward, i will try to tweak the controls a bit to set a new higher point. Instructions are definitely not clear about that, it only says to use the provided film pattern (which i dont have) to set it.</p>

<p>So i received this Densitometer and got the manual but no original calibration film nor plaques (for reflection calibration). I have borrowed a step wedge with five calibrated film strips (known densities).<br>

I am trying to calibrate de DM-201. After entering the CAL mode for transmission, it first asks for an inicial measurement without any film. That´s ok. Then it asks for the original calibration film to be measured to complete the process. Since i do not have the original, i place one of the strips i have and take a measure. It then shows 1.54 in the Visual Mode display. BUT none of my strips is 1.54. I have one 1.25 and another 2.05 as the nearest densities. Any strip placed as the second (high) point, shows a 1.54 value and then SUCCESSFUL calibration. Apparently the original calibration film strip from Noritsu is a 1.54 density film. So where should i change this value to one of the known values that i have in hand? As far as i understand, the unit is not properly calibrated until i have a 1.54 density film or until i change the internal setting so that the second (high measurement) is one of the strips i have.</p>

<p>Paul, those articles actually summarize everything i needed to know and that were also cleverly exposed by Alan above. It is now shortened to a simple task to be done: Discover the correct exposure time for the test negative contact print. Thanks a lot you guys!</p>

<p>Excellent tip, fascinated with his first phrase: "<strong>The world needs another article in densitometry as much as it needs a bullet in the head</strong>". In fact, many books and articles have been written and re-written, but most of them lack the friendly approach i could find, for example, here in the forums.</p>

<p>I read something about contact printing a step wedge and then reading the results with the reflection densitometer to plot a curve. Maybe related to paper speed only?</p>

<p>Pretty nice, Marcus. Thank you. So if i have a good negative that prints nicely on a certain paper, at a specific grade, at a known exposure time, then all i need is a transmission densitometer to make an unknown negative to be printed (the best it can be) on THAT SAME PAPER. Correct? That´s where my second question comes: What if i decide to change the paper for the unknown negative print? Can i benefit from the reflection capability of the Noritsu to achieve good results with this new paper? How?<br>

Sorry to ask you so many questions, but this equipment was bought so cheap that i am pretty much inclined to find out how it works and perhaps save me some precious time at the darkroom. It is a DM-201 model, with Visual and Blue, Green and Red individual colours. Status M for transmission mode. Four digits show Visual, B, G and Red separately and simultaneously (nice!). Printer is working and it is in pristine cosmetic condition. Should i always rely on RED for my Black and White measurements?</p>

<p>Hi Alan, so by measuring this density range of any negative it is possible to determine a starting point for the contrast of the print. How about the exposure time?</p>

<p>I have just received my first densitometer. It is a Noritsu DM-201 <strong>Transmission and Reflection</strong> Colour unit. Working perfectly. Tried to Google for a detailed workflow so i can nail down exposure and development times for specific <strong>developer-film-paper combinations</strong> but found some very vague information. Can someone provide me some straight instructions on how to proceed? The Noritsu manual simply provides technical info, no workflow suggestions.</p>

<p>Hi Robert, please note that i am referring to prints done on a Jobo processor, fresh fixer is used every shot.</p>

<p>Great! Will post results soon.</p>

<p>I will try that too Jay. Can you guess how much should i reduce the developing times if i use 510-Pyro DEA? Ilford FP4+ ISO 100</p>