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In the last thread I mentioned I wanted to see how different gammas of one film stock impact the resulting scans. I wanted to do this because (1) this article argues that Zone 8 density should be ~1.25 while my Zone 8 density is often ~2.0, and (2) I don't want to gently caress up some expired film I had recently picked up. The idea was to do two test rolls of Delta 100 where the only variable is developing time, characterize the film speed and gamma, and then do some actual subjects using another two rolls, so I can compare how different gammas impact scans of high dynamic range and low dynamic range scenes. I just finished the speed/gamma characterization and things are not going too well. Methods: I am using a light panel to create a uniformly lit surface, and I use my camera to shoot a "dose array": exposures from -5.5 stops to +5 stops, along with one blank witness frame so I can measure base + fog. The setup looks like:  I keep the aperture fixed and only adjust exposure time, making sure that +5 lands on 1 s. Developing: I use 12 mL Rodinal in 900 mL water (1+75) at 20 C for each roll of 120, and I use constant agitation in a Simma roller. On one roll I assumed ISO 100 and developed for 15 minutes, while on the other roll I assumed ISO 20 and developed for 10 minutes. Stop: 45 mL IlfoStop in 900 mL water (1+20), 1 minute Fix: 190 mL Ilford Rapid Fixer in 760 mL water (1+4), 5 minutes Rinse: 4 times rinse/agitate/dump with tap water, two final rinses with water that was filtered and then distilled Measuring:  The resulting roll is cut up into four strips, placed on the light panel, and I use my spot meter to measure how many stops darker the frames are relative to the blank witness frame. To eliminate ambient light, I place the light meter in physical contact with the film holder sheet and I put a cap on the eyepiece of the spot meter (though this last point only impacts the high density measurements). Stops are then converted to density in a spreadsheet. Results:  The data are plotted. Film speed is determined as the place where I get a density of 0.10. So if I meter at ISO 100, and the -4 exposure gives me a density of 0.10, then the film is indeed ISO 100. But if I get a density of 0.10 at the -3.5 exposure (half a stop more light than expected), then the actual film speed is ISO 70 (half a stop slower than assumed). Fudge factors: My Sekonik can only use 1/3 stop increments in ISO, while my Hasselblad can only shoot in half stop time increments. If I don't have a frame with a density of 0.10, I have to make an educated guess. In the ISO 20 roll, I had to use the lens wide open which resulted in some vignetting. Question: I am not surprised that the roll that was developed for 15 minutes came out with a high gamma of >1. But I was hoping that the second roll would give me a gamma of 0.6. Unfortunately, it appears that if I insist on reaching that gamma by just adjusting develop time (nothing else) I would end up with a film speed of ~ISO 10, which is comically slow compared to half box speed. So, what is the easiest parameter to tune? I am thinking the constant agitation is the next thing to adjust. I had initially bought the Simma roller so I would get consistent results. I come from the photolithograthy world, where one either agitates constantly or not at all; anything in between will give inconsistent results. Since I don't like the results of stand developing, I decided on constant agitation. But if this locks in high Z8 densities I will try a roll with normal black and white developing.
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Nov 12, 2023 20:56
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theHUNGERian posted:[nerd poo poo] Tried "normal" (not constant agitation) B&W developing where I do 5 inversion in the first 10 seconds of every minute and things look better.  I'll stick to this recipe for now and only make changes to the development time as needed.
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Nov 16, 2023 03:24
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Wild EEPROM posted:You should buy a fuji gw690 Another vote for the GW690! If you can find a meticulously maintained G(L)690 for little money then it too is a dope system. Much quieter than the fixed-lens version, and the 65/100/180 mm lenses are just as amazing as the 90 mm on the GW690. But nothing on that system can be fixed, so I would not want to spend much money on it.
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Nov 26, 2023 19:05
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Beve Stuscemi posted:Thoughts on getting film through airport security (meaning X-rays)? I have a trip to LA coming up in a bit, and I plan to bring my ME Super and some rolls of film with, but I've never traveled with film before. Do I need to worry about running film through the x-ray scanners at the airport? If so, whats the recommended way to get it through security? Ask them nicely to hand inspect. Perhaps it helped that I intentionally labeled my ISO100 film as ISO3200, but either way my request was granted both times.
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Jan 12, 2024 15:33
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Jan 13, 2024 02:55
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XP2 rules. Being able to do digital ICE is a super convenient.
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Jan 15, 2024 17:36
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I have a 6x12 pinhole camera that (not surprisingly) has a ton of vignetting. While I don't mind a bit of vignetting with b/w negatives, by my calculations 6x12 with 40 mm focal length gives 4 stops of vignetting, at least 2 stops more than I would like. Fortunately my camera has a 58 mm front filter holder. Unfortunately, I am not entirely sure which filter to get. Since I cannot find a 3 stop filter in a 58 mm thread, I see two options. 1. Hasselblad 58mm Center Filter 3x (1.5 stops). Pro: it screws directly into my filter holder. Con: I still have 2.5 stops of vignetting left. Close to $700. 2. Schneider IIIC 4x (2 stops). Pro: half a stop more correction. $400 (still expensive, but less than $700). Con: 67 mm thread, so I will need a step up ring, which means the filter will be further away from the aperture and I think this will impact the correction factor.(?) What's the smart thing to do. It's not a curved focal plane pinhole camera, right? RIGHT???
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Jan 21, 2024 00:13
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theHUNGERian posted:I have a 6x12 pinhole camera that (not surprisingly) has a ton of vignetting. While I don't mind a bit of vignetting with b/w negatives, by my calculations 6x12 with 40 mm focal length gives 4 stops of vignetting, at least 2 stops more than I would like. Fortunately my camera has a 58 mm front filter holder. Unfortunately, I am not entirely sure which filter to get. Since I cannot find a 3 stop filter in a 58 mm thread, I see two options. Turns out that Hasselblad also has -2 stop center filters for the flexbody, and B&H had a used copy for sale. I'll see how it performs with a step-up ring and report back.
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Jan 21, 2024 23:12
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Wild EEPROM posted:Could you also do the square filters Can you share a link or a product name?
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Jan 21, 2024 23:54
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If a Copal 3 needs ~4 test shots before the slow speeds fire consistently (even after just one day of not using it), is that normal, or a sign of needing repair, or should I just trash it and get a new shutter?
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Jan 31, 2024 04:45
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Could someone link a thorough tutorial so I can determine if I am competent enough for this job?
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Jan 31, 2024 15:40
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I got a refurbished V850 for 50% off new price. Digital ICE is super convenient over scanning with a camera.
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Feb 1, 2024 15:23
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I thought even the V850 was only mediocre for 35mm scans. These folks argue that the V850 delivers ~2300 ppi which yields a 3200x2100 pixel image from a 35mm negative. While I don't know how that compares to a digital camera scan, my gut feeling is that a modern camera with a high quality macro lens should outperform the scanner, especially if the camera has pixel shift. Dust and scratches will be more tricky to deal with than with a scanner that has digital ICE.
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Feb 2, 2024 03:59
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carticket posted:I'm really glad to hear all this having just purchased a V600 (still in box). I don't have a good light source for DSLR scanning (or a macro) and the extra steps for getting the images is kind of annoying. I also wanted to be able to scan some of my old prints for which the negatives were ruined, and my multifunction printer can't even get a halfway decent photo scan at 8x10. Outstanding choice! I dealt with lab scans for two rolls, which that was enough to convince me that I needed my own scanner, and my Epson has been fantastic. While I did get curious how much an upgrade to a Creo would get me in terms of resolution, I had concluded that the benefit was not with the cost. Though I am still intrigued by analog printing, but I don't have the room for it. The Epson should keep you happy for a while.
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Feb 3, 2024 02:28
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Do 6x9 folding cameras with a ~65 mm lens exist? I am aware of a ton of folders with ~100 mm lenses and a 6x6 with a 75 mm lens, but the only 6x9 with a 65 mm lens is the GSW, and I was curious if there is anything more compact. Edit: They do not. I just developed a roll of Panatomic-X and it has severe case of backing paper imprint. Is it safe to assume the remaining 9 rolls I have (from same seller, with same expiration date) have the same issue? I think I know the answer: Stop buying ~~~expired film~~~ and just use Lomo/Foma when I want film with cHaRaCtEr. theHUNGERian fucked around with this message at 21:36 on Feb 11, 2024 |
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Feb 7, 2024 03:52
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Free to a good home. I even cover shipping. First USA/Canada goon to quote me gets the whole lot. Expired Kodak Panatomic-X in 120: bought off ebay, seller claims it was stores properly, I have stored it in a freezer 9 rolls expired Aug 1972, one test roll with the same expiration date shows severe backing paper imprint on at least part of the roll 3 rolls expired May 1971, not tested Kodak BW400CN in 220: I received these for free under the condition that I either use it or pass it on for free. I wanted to use these in a pinhole camera, but I couldn't figure out a safe way to prevent overlapping exposures. 3 rolls expired Nov 2006   theHUNGERian fucked around with this message at 02:58 on Feb 14, 2024 |
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Feb 11, 2024 22:58
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Acros, Delta 100, T-max 100 if you want zero grain. FP4+ if you still want some grain, but finer than HP5+. Ilford Ortho might be cool if you want to bring out freckles.
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Feb 27, 2024 15:31
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lollybo posted:I bought a medium format camera ... not sure how lugging around a huge camera is going to go. I recently picked up a Bessa II and holy crap is that thing tiny. As in, it is not significantly bigger than my A7R3.
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Feb 29, 2024 03:22
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Does anyone know a place in the US that would work on a Bessa II? I have a severe light leak that mostly impacts the rebate but also the edge of the frame, and it lines up with the frame numbers on the backing paper so I think it is a light leak from the frame counter window. I've tried covering it up when not in use, but it still leaks like crazy with ISO250 film. Edit: Or could it be something in the winding mechanism? The leak after the last frame is inconsistent with the frame counter hypothesis because I am certain it was covered up after the last shot was taken. Also, the shape of the leak is more complex for just a simple leak past the frame counter.(?) 
theHUNGERian fucked around with this message at 19:37 on Mar 3, 2024 |
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Mar 3, 2024 03:59
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Father O'Blivion posted:... I'll post some examples from the last few years if I can unearth them ... I am super curious to see your results, especially if I can buy it in 120 and have a lab process it. I exposed two rolls of Cinestill 50D and trashed (used as a practice roll for putting film on a spool) a third roll because I just hated the results.
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Apr 14, 2024 20:35
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My experiment with a 6x9 folder in the form of a Bessa II has not worked out as it has a nasty light leak past the focusing mechanism and I am struggling to find someone who is willing to fix it. If I were stupid enough to try another 6x9 folder, is there a more reliable (or easier to fix) model? Or is it all about the reputation of the seller? The alternative seems to be a Fuji GF670. While it is not a 6x9, it is at least a compact medium format camera.
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Apr 18, 2024 02:29
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Sounds good, thanks folks.
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Apr 18, 2024 14:19
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cerious posted:... I wouldn't do a GF670 ... [film flatness] ... Do you know if this also applies to the GF670W (non-folder, 55 mm lens) or the Voigtlander-branded version of the same camera?
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Apr 27, 2024 15:39
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How does one buy Velvia 50 in 120? Every time I check it seems to be back ordered. Is my timing just bad or is it effectively discontinued?
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May 2, 2024 02:18
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^Nice! Re: Velvia 50. Roberts Camera had some in stock, they just arrived, and they have a decent expiration date (07/2025).
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May 7, 2024 02:18
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| # ¿ May 21, 2024 07:48 |
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big black turnout posted:Not to gatekeep or yuck anybody's yum, this is just a personal thing, but c41 b&w feels very wrong to me While I don't love it either, digital ICE is a big selling point.
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May 14, 2024 03:28
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