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Quick post to share characteristic testing of recent ASA 2 and Orthochromatic ASA 25 emulsion batches. You can determine batch # by looking on the back of the box of plates. J Lane Dry Plate Batch 44 has great tonality, but as you can see the contrast is low with a gamma around 0.45. I recommend metering at ASA 1.5 to ensure you are out of the toe entirely. It will scan nicely (see the MacBeth chart below).   J Lane Speed Plate Batch O-14 came out really well. Pretty much exactly where I want it.  Quick blog post to share the characteristic curve for the latest batch of Orthochromatic 25 emulsion. Compared to the previous batches, I was able to reduce the base fog significantly. It is a bit fast and you can probably meter at ASA 32, and contrast is a bit high as well but it is what it is! I will tame that with the next batch.  I'm pleased to announce that Don's Photo Equipment of The Lone Star State is now stocking J Lane Dry Plates and J Lane Speed Plates!
With similar motivation as myself in getting the wonderful cameras of the dry plate era off your shelf, Don's Photo Equipment is an awesome store supporting analog photography in the Dallas area. Currently stocking plates in 4x5 and 8x10. Check out their contact info on our "Where to Buy" page.   A year in the making, the ChromaGraphica Double Dry Plate Holder Kickstarter campaign was launched on Friday, 9 August 2019 at noon. By the end of the weekend, the campaign had already raised 50% of its funding goal.
Designed to be affordable, familiar in operation, and a good quality product, if successful the ChromaGraphica will be the first mass-produced double dry plate holder to be available new in decades. The holder, released in this campaign in 4x5, 5x7, and 8x10, is designed to fit all standard backs in their respective sizes. In 4x5, the holder will also fit Graflok backs. In such a niche market as large format (not to mention dry plate), the support of the community has been essential and, may I say, overwhelmingly awesome! If you are interested in getting your hands on a holder or two, please pledge your support to the campaign. Don't assume that the campaign will be successful and that these will be available after. The campaign is going to cover the costs of manufacturing an initial production run. It cannot be overstated how critical it is that the campaign succeeds, for only by reaching the funding goal will these become a reality. The link to the campaign page is below. Feel free to take a look and enjoy the presentation we put together. https://www.kickstarter.com/projects/dryplateholder/the-chromagraphica-double-dry-plate-holder -Jason  I've slightly reformulated the emulsion to remove some lingering base fog and also make the highlights a bit punchier. So batch 42 was a test batch to do this stuff. I characterized this batch to baseline the emulsion recipe going forward. Base fog: 0.09 Gamma 1.05. Development was per box recommendations, except developer temperature was 22C. I would expect contrast to be slightly lower at 20C. I really like how plates from this batch look, as demonstrated by Portrait Test Victim #3 taken with a 150mm f/4.5 Voigtlander Heliar onto 4x5. Metering was at ASA 2 on a gray card next to his face.  I've been annoyed by and dissatisfied with how J. Lane Dry plates lose so much speed in wintertime, so I've been working almost non-stop over the past two weeks (and at a less hectic pace before then) to refine the emulsion formula so that the plates give denser negatives in the winter when metered at ASA 2. Essentially this means I've kicked the speed / contrast up while retaining the extremely fine grain. To give you an idea of how much testing, I have a stack of about 200 plates worth of Stouffer Step Wedges that I've developed over the past month or so testing and retesting tweaks and additions to get the emulsion right. (Those will be cleaned and repurposed for future orders, in case you were wondering). Starting with Batch 37 (printed on the back label of each box), you'll find a significant increase in speed and contrast. I actually overshot the mark a bit with Batch 37 and it might be a bit *too* fast for ASA 2 metering this time of year (not that I think anybody would complain), so I'll dial back the speed / contrast a stop or so for batch 38. I actually considered dumping batch 37 but to be honest I've been making and tossing so many emulsion batches and developing so many plates that I'm a bit burned out and would rather just get this out into the world since it has such nice grain and tonality. I also saw that the swirlies were starting to rear their ugly head again but I think I beat that down with additional stabilizer.. we'll see if that does the trick. That seemed to have helped, but time will tell. The first few boxes of batch 37 will be going to Bostick & Sullivan, who ordered them to restock 4x5 if you're interested in trying some out. I'll be filling my own orders from existing inventory, so it'll be a bit before the new emulsion is cycled through my store. Or, after the short vacation we're going on I might just say f' it and strip all the emulsion off the plates in inventory and recoat them. Now back to my regularly-scheduled refinement of Speed Plates emulsion and the dry plate holder prototype testing. :)  Scan of plate from earlier batch (#34), metered at ASA 2  Scan of plate from reformulated emulsion (batch 37), metered at ASA 2. They both scan in great, but the scan of the newer batch has better grain characteristics (less contrast stretching needed). Visually the batch 37 plate is significantly denser. In collaboration with Chroma Camera, I'm pleased to announce that I've begun testing the prototypes for new, affordable dry plate holders!
More info can be found here: www.photrio.com/forum/threads/dry-plate-holder-kickstarter-incoming.164990/ Time to geek out about emulsion making and characterization data for the emulsion. TL;DR: Science, science, science, then a characteristic curve plot. I've been characterizing my emulsion batches for some time now, primarily to ensure batch-to-batch consistency but also to help troubleshoot issues that may come up from time-to-time. Beginning with batch 20, I started using a more advanced mixing head when making emulsion. I wanted to accomplish two things: 1) minimize the amount of air whipped into the emulsion, which causes foaming and introduces air bubbles which are difficult to remove and increase the risk of defects such as pinholes in the final emulsion. 2) Delicately improve the shadow details to help with scanning and printing to modern multigrade paper. I say delicately because I worked to still retain that late 19th century look for printing with processes from the time period. This results in a longer toe in the characteristic curve which helps scanning and makes the shadows look really nice. You can see this in the data plots for batches 20, 28, 29 in the chart. The trade-off was decreased contrast and (I think) about 1/2 stop loss in speed. However, I don't want to go back to the old method of mixing because the plates are cleaner with less undesirable defects (vs the desirable characteristics of hand-coating the plate). While the contrast is still high compared to film, the highlights don't quite pop like older plates... or at least that's what my impression is. So I did some testing and researching and figured out what needed to be done to increase the contrast in the highlights.. the result is batch 30. I still need to go out and get some photos under real world conditions, but the batch looks promising. I'll save that for the next post. So what you see below is the raw D logH curve for my emulsion for batches 20, 28, 29, and 30. These curves were generated with a uniform tungsten source measured with a calibrated light meter ... not a photographic light meter for metering a scene, but the kind that an optical engineer such as myself would use for scientific testing (read: more precision and readings given in radiometric values). The 4x5 plates are exposed through a calibrated 21-step 4"x5" wedge at a light level and exposure time to cover the linear region of the curve. After development per my recommended method (note the temperature is captured), the plates are allowed to dry and then measured with a calibrated densitometer. Aside from the test batch, gamma is a hair under 0.8. I'm pretty pleased at the consistency of the batches (all things considered, and not counting #30, the test batch), which is something that I've spent a lot of effort to ensure. I think I do need to kick the speed up a bit, just based on taking photos outdoors in the New England winter. I don't think the mixing method changed the speed, but highlighted the speed loss from some other source (if that makes sense). I have a couple of suspects, but I still need to test... in any case, increasing speed isn't difficult. So I'm at a decision point One note: Take the log H axis values with a grain of salt: The specific values were loosely anchored to bright sunlight conditions in early fall New England, and of course this a non-panchromatic, non-orthochromatic emulsion varies significantly with the ambient UV levels, so you can only get in the ballpark (~ASA 2) for practical metering purposes anyhow. What it does show is that this emulsion is much slower than modern films (duh), and is what you would expect if you were to make your own without sensitization. In an upcoming blog, I'll compare to what I get when I add a sensitizer such as sulfur or gold .. an important step for getting to "handheld speeds". :)   Rocks and Tree, scan of a batch 30 dry plate Wow what a year!
Before I reflect on the past 365.25 days, I want to thank everyone in the photography community who has been so supportive and welcoming to me as Pictoriographica started and continues to take off. While dry plates are awesome in and of themselves, it's all the wonderful and fascinating people I've met and talked to, exchanged emails with or had to honor of enjoying their dry plate results that has made this venture so much fun and made every hour of lost sleep worth it. I hope you get as much enjoyment out of this exciting new world of dry plate photography as I have in interacting with all of you. You rock! On 20 December 2017, I posted a classified ad here advertising the sale of some extra 4x5 plates, packaged in spare three-piece sheet film boxes with a fun label to make them look cool. J. Lane Dry Plates were born! I posted the ad and went to sleep, figuring *maybe* someone might buy a box over the next few days. The next morning I discovered the three boxes of plates had sold in about 15 minutes, and I was shocked to find that my inbox and the ad itself was inundated with requests for more 4x5 and other sizes as well. Since my Christmas break had started, I had no reason not to just run with it. I ended up sleeping very little that break. A year later, primarily because I've brought on a couple of awesome high schoolers to help part time (more on them later), it's only been *just this month* that I once again get to enjoy the luxury of 8-hours' sleep. It's been a great ride so far. There have been snags and hiccups along the way (I hate swirlies and thin plates), primarily related to ramping up the quantity of emulsion I've had to make (almost 100 Liters), the number of plates I've coated (about 10,000 plates), and accommodating all the different ways that people other than myself go about processing them. Fortunately, my technical background (almost 20 years as an engineer solving really hard problems) has enabled me to isolate and address the myriad of issues that have cropped up while improving the quality and -- most importantly -- the batch-to-batch consistency of the final product. As most of you know, this is a side business: I have a full-time job as a systems engineer (formerly lens designer.. I'm moving up in the world) and have kids with all the kids activities that go with it. So my "Pictoriographica Work Day" really starts at around 9PM. As demand continued to grow, I simply couldn't keep up. I had no time for anything else. So last month, I brought on board two awesome part time workers to help me keep up with demand. They are both high schoolers, incredibly enthusiastic about film photography, who are hard working and weren't looking forward to flipping burgers as a career starter. Jack cuts and preps glass, while Laura is quickly gaining proficiency in coating plates. Chances are if you've ordered plates this month, the plates you receive were prepped primarily by them (I've been doing QC while they come up to speed and still pack them and ship them out). The great thing about that is it frees up time for me to sleep and also gives me time to get back into doing R&D to develop new and interesting products. Faster speed, you say? Orthochromatic? New *affordable* dry plate holders? Even cooler things that I dare not even mention yet? 2019 should prove just as refreshingly fascinating as 2018 has been in the world of dry plate photography. So the first cool news for 2019 will be a new "experimental emulsion shop". I will be standing up an online store here on the website to make available plates coated with some of the experimental emulsions that are the fruits of my ongoing research and development. These experimental batches typically generate more emulsion than I really need for testing, so rather than dumping it out I'll make it available to you to play with. The listings will provide some basic characterization info and an approximate ASA value to meter... with the caveats about metering ortho or unsensitized plates applying, of course. These will be "one time runs". Once they're gone, that's it. They'll be replaced with the next thing I'm working on. So that should be fun. I'll close this blog with this: As long as there is a demand for dry plates, I will continue to make dry plates. The original J. Lane Dry Plates will always be available, to preserve the look of the dry plate era and ensure it is readily available as an additional tool in the photographer's toolbox of alternative processes. Happy 1st Birthday, Pictoriographica! |
AuthorI'm the guy behind the curtain, Jason Lane, coating plates instead of sleeping. Archives
September 2019
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