murrayatuptown

Thank you both. I knew there was a reason I kept the toaster oven my wife acquired on Black Friday last year for $10. Unfortunately I forgot what I wanted to do with it and donated it to a charitable organization this summer... I guess I will start by looking. The CO2 absorption sounds like the largest uncertainty. Good news, (I guess) is that the only material stored in the garage was the 25# tub of sodium thiosulphate. Won't be the first time I wasted money trying to save money....

Hello:. Old thread, but it makes more sense to me to ask a question here I think is relevant here than start a new thread. I recently got a 1937 (?) Agfa Jsolette (black plastic top) with Jgestar lens. I got the the front cell free with a hair dryer. It had no visible green lube solids, so I guess someone else had cleaned it out but not replaced lube. Bellows is better than other Agfa's I've had, perhaps old enough to be pre-synthetic... The focus ring set screws are too chewed up to re-tighten. Does anyone have any advice regarding replacement set screws, or at least identifying the thread requirement? I sometimes resort to digital calipers and counting threads under a microscope, but these are so tiny I think I'd be talking myself into believing whatever I rationalized my measurements to indicate. I just now realized my question is about' old threads'. Thank you Murray

Hi: I bought many bulk chemicals years ago & procrastinated my big ‘development’ plans...but hope to get going this year. I am concerned about the gradual hydration into different crystal forms by some of the chemicals like sodium carbonate, borax, sodium thiosulfate, maybe sodium bicarbonate & lye. I assume the washing soda & ‘thiosulfate will have gone to decahydrate, and vaguely recall there may be be two distinctly different crystal shapes for the latter (‘rice’ vs. ‘complex?’). Lye I suppose could just turn to slime...if it did, weighing it meaningfully may be a problem. The baking soda doesn't seem to change appearance in the kitchen. Any helpful visual cues from someone who’s been there, done that? Thank you Murray

Looking at some of the two-bath recipes...don't have any Metol or HQ, so I found LOMAD developer, which is apparently a clone of Diafine...has ingredients I already have, I noticed the similarity to other logarithmic relationships, too, but never thought of using dB there...I feel like I'd have to insist on measuring optical power to use decibels. imsphotos: part experimental, part salvage. Not really afraid of being embarrassed by a totally washed out roll, but realizing by no-brainer mistake, rescuing images would be a reward of sorts...I might not have learned about two-bath development otherwise. Speaking of pretentious Roman numerals...the Heathkit company made several clock kits, the most abominable being a wooden mantel clock with dot matrix LED Roman numerals, using individual (5 mm?) LED's. It used some quirky logic to avoid too-wide-for-number-of-LED's numeral combinations like IIX instead of VIII...correct but 'unconventional'. Even if you were comfortable reading Roman numerals rendered in primitive dot matrix, the bright red LED's clashed with the traditional wooden clock case.

E-mailed Marco...he had a diagram of another version that shared enough with my configuration to be a helpful reference. I'll clean the fingerprints off & try reassembly per the closest illustration.

I just looked at the Marco Covina site which compares 'schematics' for Leitz Wetzlar Germany Colorplan 1:2.5/90 lens with an Elmarit f/2.8 lens, and describes differences between the German and Portuguese Colorplan projection lenses. Mine is German, but differs from the Mandler-Wagner (Covina-posted) 2009 drawing, in having TWO doublet/achromats and some visibly different element shapes...perhaps a transitional design. I took closer edge photos of my elements but they are on my phone at the moment. This isn't going to get easier, I guess.

I picked up a Leitz Wetzlar Germany 1:2.5/90 projection lens that was hazy. I thought I kept track of the element order & orientation when I took it apart to clean it, but it rattled after reass’y. I took it apart again today & laid the elements out in order. There are only two flat spacers and one is wider in diameter and won’t fit inside the barrel...so it has to be the ‘retainer’ between the front element & ‘nameplate’ ring. Online optical ‘schematics’ only show the elements, not the spacers. Maybe I just didn’t have the elements fully inserted & didn’t want to force anything. Any experience with this? Thanks Murray

Probably only 6-15 feet. I started at maybe f/4, then decided to stop down to f/11-16 and rely on DOF as I couldn't see well enough to use the split + Fresnel screen. The room lighting was EV 4-5 (phone light meter)., so I didn't even try any with the flash off. Thank you

Hello: I did an experiment a couple weeks ago with a camera and flash I had never used before...some rationalization and some mistakes leave me with a developing decision to make to possibly salvage the exposures. I just got a Bronica ETR with the AE eyelevel finder. I had an Agfatronic 643CS flash I've never used...relatively large; IIRC GN 212 @ ISO 100. I shot a roll of APX 400 at a wedding reception as an experiment after the paid photographer left...not my job. I put the camera on autoexposure and told myself the flash had a thyristor...but I had it on full power. I used the built-in diffuser, but someone squawked about how bright the flash was. I rarely use a flash so I didn't know what I was doing. I haven't developed the film yet and it's been on my mind that I may have overdone the lighting...a bit. So I am contemplating what I can do to rescue the roll. Maybe POTA is a bit extreme, but that's what I'm thinking ...I have the chemicals. That or diluted stand development. Any advice? Thank you Murray

Thanks for explaining WHY the mod has to be done. I had read about it elsewhere being not essential and wasn’t grasping there wasn’t sufficient clearance...I thought it was carelessly slamming the darkslide in. Sounds like a headache eliminator. I wish I had more of the Graflex edge-groove type. I have 6x as many ‘Type 5’ with solid (no groove) edges. I’m more interested in trying this on a Graflex Reflex RB Series B than a Baby Speed...the former is simpler & easier to hold, being ‘boxier’ & shorter. Now I wonder what holders Types 1-4 are but it’s more disturbing to realize how many differences there might be among multiple brands. Camera makers certainly didn’t need to wonder what people would be puzzling over several decades later.

Thank you. Good point. I subconsciously do that in other electronic debug contexts when I don’t know what in-circuit characteristics to expect...so I check with both ohmeter test lead polarities, and if observations lead me to, I’ll check in diode mode &/or capacitance mode. Sometimes those observations can be compared to a 2nd identical item to clarify whether the unknown measurement is normal or at least typical. That’s when I have a tech hat on. I rarely put the tech hat on when thinking about cameras. Thanks for the reminder. & thanks Paul Ron for solving the puzzle.

Hi: Anyone know if Bronica ETR in-lens (MC) Seiko shutter PC flash synch contacts are simply mechanical/metal, or semiconductor? I have a mix of flashes with widely ranging terminal voltages...most recent one I checked was over 175 VDC...another was only 7.5, but I forget which that one was. If I can avoid frying any integral semiconductor switching, I’d like to try. I do have a Yongnuo trigger somewhere too (RF-603?)... Thanks Murray

I was just given an ‘antique’ (2001) Nikon D1X with a 28-200 zoom lens that moves the distance ring but not the optics (doesn’t focus). Manual rotation doesn’t help and it occasional won’t rotate (loose parts?), I am not putting any chemicals in it. I was debating (with myself) whether to toss it, take it apart, sell it for parts, or... Surely not worth the cost of repair... But last night I found it’s ‘parked’ at the ‘low end’, about 2 m (seemed closer to me)...I was able to ‘shuffle focus’ like I’ve done with fixed focus lenses on a mirrorless camera. Then I thought I can stop down for DOF...it still passes light & focuses SOMEwhere. Have to find a CF memory no larger than 1 GB first...looks like that is a little easier than 127 film...neither is available locally, mail-order options appear over extreme price range. Hmmm, expired pixels, expired film..,

Be careful assuming specific brand aerosol solvent products with functional names like ‘electronics cleaner’, ‘precision parts cleaner’, etc. will have the same recipes forever. I have used some that evolved, and kept the same product name but changed the product number due to formulation changes (to reduce/eliminate certain classes of chemicals). Miller-Stephenson brown-text Precision Cleaner (I don’t have a can of it handy to give the product number) has changed drastically. Eliminated the chloro-fluoro type components, replaced with some other, and while it is fine on metals, it is now very aggressive toward some plastics but not others. I have tried to use aerosols outdoors to reduce odor/inhalation, and they cool upon expansion from the compressed state, causing a lot of condensation in warm weather...now there is water all over when you started with a water-free solvent! Another really bad mistake was using a Teflon-containing liquid. That shutter now only works at 1/400! I tried the same solvent base the Teflon-enhanced product had, hoping it would re-dissolve the ‘Teflon-coating’ but no such luck. It’s everywhere inside. Not worth paying for a CLA, and I don't need that camera enough to shop for another identical shutter (easy because it’s on a lens-board, but I do not need/want).

Thanks. No plates...just different stamped numbers. The person who gave it to me confirmed his uncle made the added rear rise hardware including the gears, in his basement shop...he watched such machining frequently in amazement. He said it could have been an ‘economy model’ as the aunt was a college student photographer before a ‘pro’. I’ll revisit when I have time (wedding, houseguests, etc). Thanks

I was given a much modified plate camera by a descendant of the original owner, whose husband made add’l parts to add rear rise/fall. The next generation wanted to refinish it and it is in pieces, side-lined, retirement & a move, and I took on the challenge. (Lunatic). I took some photos of the wooden parts. The hardware was in a separate bag. Much of the hardware is a weird satin gold, which makes me think it is steel and not brass (possible clue). The focus and front racks are brass. I think I see enough tailboard cameras online to call it that. The wood is not mahogany...something much paler and stained...like boxwood, pear, probably not poplar, but that kind of grain. I am emptying a room for imminent guests and may not be able to find the camera for add’l (hardware) photos for a month. Some of the wooden parts have numbers stamped on them. Most do not, and none match. I’m hoping there is enough detail for a guess at what it might be, have been, or evolved from. Any opinions/help are appreciated. Thanks Murray

One of my previous responses for some reason is pending approval. I referenced a Swedish author’s paper on optimal pinhole. He explains (physicist, IIRC) there are other subjective differences that affect your perception of sharpness (which is on a scale ranging from low to very low). MTF and spatial frequency (don’t need to know or care) affect contrast which affects perceived sharpness...and different subject matter can have different ‘spatial spectral content’... his conclusion is that a slightly smaller pinhole constant generally leans toward better contrast & perceived sharpness...what Jim Jones endorsed. https://www.kth.se/social/files/542d1388f27654460dee76cf/Pinhole.pdf

If not evident, Instax film appears to only be available in ISO 800 speed.

Dave Rollans has a ‘doable’, if awkward, method of shooting Instax Mini in 2-1/4x3-1/4 ‘groovy’ film holders on RB-67. It requires sliding the unexposed Instax Mini films out of the pack in either a darkroom or changing bag, & loading them into double dark slide film holders. After exposure, they get transferred back into the empty Fuji pack which is returned to the Instax Mini camera and with the lens blocked from light, they can be processed by ejection thru the camera film rollers. He recommends altering the film holders to reduce the degree of care required to avoid bursting the developer packets (bursa?)...but it’s not mandatory. What problem this method does solve extremely well is that of figuring out how to position the Fuji films precisely at the focal plane. The methods of butchering a Fuji camera to mount on another camera with the film spaced in agreement with the ficusing screen without film relocation to other holders is hit or miss...I’ve read enough disappointing descriptions to prefer taking my chances doing the film unload/reload/unload/reload/process. Before you get bored, Dave’s Blog from May 26, 2017 (in case my copy/paste from my phone only gives the top of the blog page) is here: Instax Mini Film in Medium Format Cameras Hopefully this link has the 2nd link to his videos showing the simulated process in daylight for educational purposes. It requires a functional Instax Mini camera for processing. I recently acquired a ‘gently damaged’ Mini Neoclassical 90 I have lucked out with so far in getting around the damage...but haven’t shot any film yet. As the first film test approaches, I’ve contemplated my other options since I have only uncovered ‘non-groovy’ 2-1/4 x 3-1/4 holders in my basement...so I cannot use them on an RB-67. I have two ‘baby’ press cameras with spring backs that don’t require the filmholders to be grooved, however. I also have a Kodak Medalist 2 with cut film/plate back, and both the 2-1/4” x 3-1/4” and 6.5 x 9 cm metal single exposure holders (Kodak/Recomar type). What I have found with this is that the Instax Mini film is a little long for the film guide tabs in the Kodak/Recomar 2-1/4 x 3-1/4 holders...causing the film to bulge/buckle away from flat. The 6.5x9 cm holders have enough room to accommodate the Instax Mini films, with care...a bit too much room...but watching which way is up and down when inserted into the Medalist back would allow careful loading into the metal holders so they don’t shift. The Instax Wide has my interest too, but I think I need to get some results with the Mini first before butting heads on eBay with others bidding on as-is non-functioning cameras...but I wonder what they know that I don’t yet.

Obviously I meant to type 2018, not 2918. I hate touch screens. Thanks

I see 100 packs of C200 on eBay at ridiculously low prices these days (Aug 2918), most, but not all from sellers in China & one other Asian country I forget. I found one US seller. Are people so eager to dump it now due to disinteres, or have I found another scam?