ben_hutcherson

Yes, that's what I'm trying to tell you! After ~12 hours of being logged on, the site will go into an endless refresh loop and be rendered useless. The only solution I've found is to log out and log back in. This DOES NOT happen on other Xenforo site I visit. The issue is here and only here. I've posted details about this problem at least a half dozen times, and I'm not the only one reporting. Please also don't try to blame it on using an outdated browser or OS as you did the last time I brought this up. I am as current as I can possibly be on these fronts with macOS Sierra(up to date) and Firefox 54.0. BTW, the problem also happens running Firefox 54.0 in macOS High Sierra.

My specific issue-that I've reported numerous times- is what I'm calling the "spastic refresh" that several folks are reporting, but that you claim you can't repeat. None the less, it's happening and I'm not the only one. It just happened again when I first got on the site this morning. I know you said only one person knew TCL. That still seems to be one more person than knows Xenforo right now.

Okay, so as promised here is sort of the "master" experiment. I didn't photograph as much as I should have, but this should give you an idea. First of all, I took 200mL of DI water then added 10g sodium carbonate. Once it was completely dissolved, I added 1g caffeine, and a few hundred milligrams of AgI. I left this heating and stirring for several hours, but the solution remained unchanged. It was clear and colorless with undissolved AgI on the bottom. I didn't have a LOT of caffeic acid, but I added about 200mg, and within a couple of minutes I had this I decanted a small amount of it off I THOUGHT that this was elemental silver, but just to make sure I did a little classical chemistry and added nitric acid. The black flakes readily dissolved in nitric acid. And, just as a double check, I added sodium chloride and got a white precipitate. That can be assumed to be AgCl. Finally, I ran a side experiment that I didn't do as much with where I added sodium carbonate and a few hundred milligrams of caffeic acid. This is what it looked like when I put AgI in it.

Alright, after a bit of experimenting I can pretty safely say that caffeic acid and NOT caffeine is the active reducing agent. I will give a full write-up later this evening, including photographs.

That's actually a really good question, and one to which I don't intuitively have an answer. Neither actually jumps out at me as having a site that can be easily oxidized. When a good chemist doesn't know, though, he experiments. As it so happens I have both caffeine and caffeic acid on hand. It should be easy to mix up each in a solution with sodium carbonate and see what happens when you add in a small amount of silver bromide. Even if I can't visually see it, I should be able to do it in-situ in a UV-VIS cuvette. Both caffeine and caffeic acid absorb in the UV range, and any chemical change that comes about from them being oxidized by the AgBr should show up as a change in λmax. I do note with some interest that most caffenol "recipes" that I find also specify the inclusion of ascorbic acid, something which is well known as a reducing agent. I remember when caffenol was first making the rounds, it was described as being a VERY slow developer-I can't help but wonder if, like you said, something else was actually behind the development. I suspect coffee contains a small amount of ascorbic acid-it may be that's the active ingredient anyway, and in current ascorbic acid forumulæ the coffee is on there "because."

20mm and wider lenses have the ability to be very "powerful" lenses. The results from them can be phenomenal if used to their potential but also a disaster if used wrong. There again, that's where I go back to a 24mm being a great starter wide angle. You can still push it to get the "wide angle" look that so many of us crave, but it can also be used in a pinch for general purpose photography. If you're photographing people, just keep them away from the edges of the frame! As a side note, you may well know this but many folks think about a wide angle as being a lens to "get it all in." In truth, the most compelling uses of them often do just the opposite. The fact that you can get almost on top of something you're photographing not only can cut out foreground clutter but also use the inherent distortion to your advantage.

That's nothing-with Greenspun at the help, I seem to recall Alexa rankings in the top 2500 worldwide. I've been on a hiatus from the site for several years now, but it's honestly discouraging to see how things have declined relative to what I remember in the 2006-2008. It was such a privilege to get to work alongside Phillip as a moderator back in those days. I'm also sorry to see that a lot of the old active members of the moderator team I remember-folks like Bob Atkins and Lex Jenkins-seem to have faded into the background. When I look through the fora now, I see very few familiar names as moderators-Shun on the Nikon forum is one who stands out, as is James on some of the film fora. I can't explain why the current trend is such that it is, but I'm just sorry that this once great giant seems to be sailing into the sunset. In all honesty, I don't know that the original software was driving away new members. What does seem certain, though, is that the bugs are driving away OLD members. Let's face it, in a web loaded with crap from every direction, the old Pnet was a relief with its minimalist but very effective interface. BTW, I still don't understand why some of these problems can't be solved. This isn't the only site on the net running Xenforo, nor is it the only Xenforo site of which I'm a member. The issues I'm having here(and now the spastic refresh problem is my biggest one) just don't happen elsewhere.

I have located everything but the 135 f/2, but am still interested in one of those.

No, but as I said gelatin and the polymer base are. Also, the dyes in color film are all organic compounds. The Bayer pattern filters on CCD/CMOS sensors are also organic compounds

I don't recall seeing no photography signs or being hassled for it ~10 years ago. It's a good chance that I just blended in, though, since I didn't have the camera to my eye when taking pictures. At the same time, though, I was often taking meter readings(with the camera) a minute or so before actually taking the photo. I'd have respected no photography signs if posted or if asked to stop. I have a co-worker who walks around now when he's traveling with a 28mm lens on an A7 and shoots from the hip when he's in places that don't allow photography. He has some amazing photos to show for it, albeit often with a lot of cropping.

I'm a wide angle junky, and I don't currently own a 28mm prime in either of the SLR systems I use(Canon FD and Nikon) although I have zooms covering it. I have a 24mm f/2 and 20mm 2.8 in Canon FD, along with a 24mm 2.8 AI and 20mm 3.5(pre-AI) along with an 18mm 3.5 AI-S on the way in F mount. I've had 28mms and sold them. In all honesty, 28mm and 35mm focal lengths just don't excite me that much. I love the "in your face" perspective distortion of wide angles, and to me a 28mm just doesn't get me there. I don't find that I can really get the effect until I get to 24mm. With that said, only you can decide if it's a lens for you. One of the nice things about AI/AI-s lenses is that if buy one for a reasonable price you can probably resell it at little to no loss or even make a little bit. So, I'd encourage you to at least try. At the same time, I might encourage you to spend a bit more and get a 24mm. To me, 24mm is a more versatile focal length as it can be pressed into "real" wide angle service(albeit without results as dramatic as a wider lens) and is JUST long enough that you can make it work in a lot of situations.

Anything that contains carbon-carbon bonds is organics. That applies to the substrate in film, the gelatin, and all the developers I know of. CCD and CMOS sensors both contain organic compounds in their construction.

I bought and played with a couple of Ebay cheapies. Most did reliably cut-off at their specified value(I only bought 720nm filters) and were more or less visually opaque, but showed pronounced transmittance up past 400nm or so. This might not be a big deal in digital, but it kind of kills IR film. I finally bit the bullet and bought a Hoya R72. I think it was around $70 from B&H. I bought the 72mm version, although now that I'm into a system that mostly uses 77mm filters(Mamiya RB67) I wish I'd gone ahead with a 77 or 82. As long as you're not using wide angles, cheap step-up rings will serve you fine and IMO are a better choice that buying an expensive filter in every size(for a lot of SLR users that's going to be 52, 55, 58, 67, and 72).

I'm looking for the above lens, plus a few others-all in AI or AI-s versions. I should add that all lenses MUST still have their metering prongs installed for me to be interested, or be priced low enough to cover the cost of having it(re) installed. 105 2.5 135mm f/2 200mm f/4 I'm also interested in buying any metering prongs and associated screws that you may have removed from lenses and have kicking around in your junk drawer.

Thanks Gary. It came apart exactly as you described. I cleaned the threads and detent surface well and then put a thin coat of Moebius 8200(mainspring grease for ~10 size and larger watches) on both the threads and detent surface. Unfortunately, that didn't give me any change, so I guess the lens needs to come apart further. I'll have to decide if I want to live with it, tackle it myself, or have someone else do it. BTW, I loaded up one of the cassettes with some long-expired TMAX 100 and put it in my F Photomic. I'll see how that turns out.

I have never done precision rifle shooting, but have ATTEMPTED NRA Bullseye handgun shooting. I bought an S&W Model 14 from an old Bullseye shooter, and I actually to replace the trigger rebound spring in it because I inadvertently fired it more than once when lining up the sights on a shot(slow fire 50 yards). The spring I took out was around 12lbs, and gave a single action pull of right at 1lb. I put a 14lb spring in(lighter than the factory 16lb). That didn't affect the crispness of the pull, but did give what was-for me-a more manageable 2lb pull. When I attempt Bullseye now, I use an S&W 52(semi-auto 38 special wadcutter gun) for the centerfire slow fire and rapid fire. It has its factory springs and is also right at 2lbs. When it comes to cameras, one of the things I've always appreciated about the Canon New F-1 is how light the shutter button is. You don't notice it until you fire the camera without a battery in it :) . Of course, virtually all modern cameras have minimal travel and are designed for you to easily "roll" your finger onto the release. On the MF front, I'm often pleasantly surprised at how light the release is on the RB67 as well as how minimal the amount of mirror shake is.

I have a pre-AI 50mm 1.4 chrome nose with a stiff and "squeaky" aperture ring. The aperture otherwise works fine-the ring just doesn't work as I'd like it to. I'm a watchmaker as a hobby to have what should be the appropriate tools and clean work environment to get inside, clean the mechanical parts, and the appropriate lubricants(Moebius greases) to put it back together. I'm not planning on digging into the optics-I just want to get to the ring itself. I'm just curious as to whether or not someone can offer advice on potential pitfalls or other things to watch out for when I do this. From what I've seen, it looks to be a straight forward operation, but none the less I don't want to bit off more than I can chew. Thanks.

Ed, I've made extended trips with nothing but Superia 400 in my camera bag. I agree that it made a lot of sense as it was a perfectly usable film with good color and modest grain. I still have photos taken inside cathedrals in France where I let my A-1 dangle from my neck while I leaned against a wall. Outdoors, I could still use largish apertures when I wanted to, or hand hold easily in overcast shadowy conditions. There was also the benefit of quite literally every news stand/whatever shop having some if I ran out(probably not true today). With that said, these days with film I'd rather select a film for the occasion than use general purpose one. When traveling, high end plasticy consumer bodies like my beloved A-1 and the much newer F100(or EOS 3 if you want to use the EF system) come into their own since two or three of them weigh as much as an F-1, EOS 1 series, or F4/F5. When you get into modern bodies pro bodies with integral motor drives, there's also a big size advantage.

I guess it's a difference in philosophy. I approach the technical aspects of film photography as a scientific exercise. I know that the medium I use(in color, the process type and film stock, in B&W the film stock, developer, etc) will introduce its interpretation, but I consider it part of my job as a photographer to learn and understand how the medium will dictate the appearance of the final product. Knowing the medium allows me to use its strengths/weaknesses to my advantage in my composition. Thus, I want predictable results from a film stock, not an element of randomness. I guess that's a side product of my background as a scientist, but the chemist in me also wants reproducible results in a developer when I'm formulating it myself. BTW, this is a side note and no one has brought this up in this thread, but along those same lines I DETEST the use of "analog" in reference to film photography. Film grains are either there or they're not. Density forms from increased grains in a certain area, not from one individual grain becoming more intense. That's as opposed to "digital" photography, where each pixel on the sensor has a response proportional to the amount of light falling on it.

I will fully admit that the only auto focus Nikon I own is an F4, and my only DSLR(a Canon Rebel XS) is a used about 80% of the time on a tripod in live view mode with me manually focusing with the computer screen. With that said, on both the F4 and the Rebel the AF module doesn't seem to care where the aperture is set when it's focusing. I also only have "screwdriver" AF lenses for the F4. Low end and early AF systems tend to "hunt" in low light even when you put an AF point directly on a high contrast area(i.e. I'll often use a white door frame against a darker wall when testing/playing with AF), but focusing is done wide open and I doubt that the AF module pays attention to the aperture you're going to use to take the shot since that could change between the time you focus and when you actually take the shot. The only time the aperture is going to come into play is, again, if you're in low light and using a slower lens. Even though the camera is focusing with the lens wide open, it still has less light falling on the focus CCDs to work with. That would not be an issue with a 35mm 1.8. In fact, going to my limited selection of zoom lenses, I find that my F4 focuses faster and more decisively in lower light situations with a 50mm 1.8 than it does with a slower zoom. I do have one zoom that beats it in bright light since it's geared much faster, but the 50mm wins in marginal conditions. BTW, I'm eying an F100 in a local shop that most likely will be coming home with me sometime soon, so I'll be interested to see how a somewhat more modern AF system does. I'd jump on a D750 at the current low price if I had a spare $1500.

Mac OS X Sierra 10.12.4, Firefox 54.0. My OS may be a build number behind current, but AFAIK Firefox is within a week of the most current version. The problem happens when I'm logged into the site for ~12 hours.

I'd still appreciate an answer to the spastic refresh problem that several of us have been reporting. This stuff would not have happened when Phillip still owned/operated the site.

I just picked up a Nikon F FTN, so I'll be having some fun with that one. I'll probably spool up some TMAX-100 in the Nikon reloadable cassettes I picked up not too long ago and shoot it. I've just made a deal on an AI-s 18mm 3.5, and I REALLY wish I had that in my hands to play with. I guess that one will have to wait for next weekend. I'm a wide angle junky, but have never used a(full frame) lens wider than 20mm. I feel dirty to have been buying so much Nikon stuff lately. I didn't get around to using the Canoflex last weekend, so I'll give it a bit of love also. I'm anxious to see how the meter does. I need hunt down some R-mount lenses, as FLs are a bit inconvenient, breech lock FDs even more so, and nFD lenses can't be made to work at all. I'm kind of sorry that I passed on the $50 one with the included 50mm right next to the $25 I bought, but then if I go back it's probably still there.

And, as a side note, I was putting together an experiment back in the spring semester(GC-MS analysis of caffeine in beverages) and couldn't find any caffeine in the stock room and only about 10g in one of the labs. We hadn't ordered any in years, and I guess that we'd finally used it all up making the standards for the pain tablet experiment I mentioned earlier. I ordered a 1kg bottle, and I'll just say that I can't possibly imagine someone taking that much of it. Like a lot of organic solids, it's very "fluffy" and 1kg mostly fills the 1L size bottle it's packaged in. That would be a lot of powder to ingest, not to imagine that I suspect that being an amine it would have a terribly bitter taste. I've never gone out of my way to taste it, but the small amount I've inhaled(remember, fluffy powder) when weighing it out didn't leave a great taste.

I've never bought No-Doz, but a quick Google search shows 60 ct. bottles. That's 12g of Caffeine in the bottle. For adults, the LD50 of caffeine is roughly 200mg/kg. For someone who weighs 90kg(~200lbs) that amounts to 90 No-Doz pills, or less than two bottles. If you're more on the order of 55kg(~150lbs) that makes less than a full bottle a lethal dose.