patrick_ingram

You may or may not know this, but this month's issue of Black and White Photography Magazine (the British one) has an article on paper negs.

I think the packing has changed (will change), as will the naming convention. Tmax 100 is now called 100 Tmax or something... the film speed comes first on the new packs... I think

Exposure times at night can be very long. With reciprocity in the mix, you have a very wide range of reasonable exposure times. My usual exposure time is 6 minutes at f/22 (with HP5+). For one stop more exposure (according to the reciprocity characteristics for HP5+), I would need to expose for almost 10 more minutes, for a total of 15.8 minutes. And a one stop overexposure isn't the end of the world. The point is, just try a few reasonably long times and you should be fine. To get a nice print, though, you'll want to pull the film a great deal to handle contrast. I cut the developing time by around a factor of 2. Of course, you don't want to go below 5 minutes in the developer.

Although, as Al mentioned, the ISO 5000 claim here is probably not true ISO, I just read an article about a developer created by Kodak which, the article claims, allows a TRUE ISO of 3200. The article had densiometer readings to back this up (unless they just made up the numbers). The downside is that the grain becomes so large that the negs are unusable for normal photography. It seems that the developer (D-19a, a modified version of D-19) was created for use at horse races (for photo finishes). Has anybody tried this?

As a chem student you might have easy access to raw chemicals... if so, you might want to pick up a copy of the Darkroom Cookbook. Lots of fun stuff to play with in there.

Although the logic is flawed, it also doesn't imply what you think it does. If a stop were simply equivalent to a factor of two in reflectance, then a 10 stop range would easily be accomplished. So would a 8390183901489012 stop range: 100%, 50%, 25%, 12.5%, 6.75%, .... ad infinatum

My Photo club has a seperate JOBO tank and reel for Pyro. Pyro will (so several of the old-timers tell me) slowly stain plastic (brown), and this one tank/reel is stained, but I don't think the stain reacts in any way to other chems.

I wasn't going to get in on this but... didn't Kodak just start up another production facility? Do you really think they plan to use it for five years and then pack it up? Some would argue that Kodak may have made a business error, but if they keep producing film it will keep being available.

If you were using ttl metering, your exposure is ok (as mentioned above) as the meter was looking though the filter. Otherwise... a filter factor of 2.5 corresponds to 1.32 stops, not 2.5 stops. So go for a +1 and 1/3 stop push, or a film speed rating of 250 ISO (2.5 * 100).

Daniel... what's all the "eh"ing aboot, eh? Are you being a yankie hoser? Or are you a Canuck like Jack and me? :)

Well, here's my suggestion: if you really can get fresh HIE (I guess Kodak will custom-make small runs) you should see who else on this forum would like to go in on a run of 20, and split the cost. Did the store owners say how much it would cost? I'm a starving student, but I might even be interested (how fun is food and shelter compared to infrared film?).

I tried Ilfochromes once... and was thinking about trying again. It's fairly easy... but a bit on the pricey side. It's also time consuming. If I recall correctly, processing each sheet took about 20 min. If you're doing test-strips for prints this is a bit prohibitive.

RE the ISO of Delta 3200: Ilford says it's 1000, but this may not be determined with the ISO method. I seem to recall reading in some Ilford tech sheet something to the effect that their suggested speeds are based on "good negs" not on ISO standards. Also... your choice of developer will change your results. Delta 3200 might have ISO 1000 in microphen, but not in perceptol. The best test is how good the pics look.

Is there any way that the good folks at photo.net could provide a seperate set of html files that are as handheld-friendly as the old forum? All of the html junk at the top of the page now is somewhat annoying. I assume that this would be simple enough, as everything is generated.

the above links may include this, but you can get a fairly accurate

measure or the pinhole diameter using your enlarger. Just pop it in a

film carrier, raise the head, focus the hole, measure and reduce by

the enlargement factor.

I win! 22, and new to LF (and loving it, except for my troubles

finding accurate developing times for Delta 100 on a Jobo)

I don't think "they" think we won't notice. They just think we'll

have to accept it, and will forget. On average, they're right.

 

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Here's an interesting thought I had recently, on the topic of

movie grain (almost): suppose we compare a digital video system with

a film movie. Suppose that each frame of film has the same number

of grains as the digital video has pixels (be dumb with me for a

moment). Shouldn't the film movie still have a higher effective

resolution, in some sense? My little mathematician brain says it

should: the "pixels" in the film are never in the same place from

frame to frame, so we're constantly "sampling" the data differently

and averaging this data at 24 fps. Just a thought.

Thanks to both of the above people. The second response works

particularly well.

Hi. I've been getting into B&W LF stuff, and am trying to get the dev times right on the Jobo. To make things easier, I'm restricting myself to Delta 100. I'm using mostly D-76 1:1 because it's free where I am, but I'm open to change. I was wondering if anyone has run any film tests on this combo and would like to share them? I realize the details vary widely based on your meter, lens, shoe size, etc., but it might help as a good starting point. I was hoping to get the true speed, and maybe times for N, N+1, etc. Cts. agitation.

 

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Thanks

I'd be willing to help out with (5), though I may need to pick up one or two skills. One of my jobs right now is typesetting for a symbolic logic journal which, though superficially different (latex vs. HTML... paper vs. web) probably involves many of the same skills. I have a passable familiarity with unix and a few of the unix text editors, etc... but what's CVS? I could spare a couple hours a week.

C'mon, Bob... camera manufacturers could just put a second metering system on a small retractable arm behind the mirror... then when the mirror locks up you can still meter, and when you want to shoot the second metering system would swing out of the way and... oh. :)

I'm not sure that I agree with everything Mr. Miller says, but there is a very good point about camera ads, and in particular camera ads that we don't know are camera ads. No-one expects camera ads to point out obvious flaws. It would be nice if they did, just like it would be nice if instead of "We love to see you smile" McDonald's ads said "We spit in your burgers but don't worry, they're made out of rat ass anyways". But that's not gonna happen since the small increase in sales from people thinking "Honesty? Wow!" would be overwhelmed by the large decline in sales from people thinking "They can't even make their product SEEM good." My question is: Are reviews in magazines really more objective than ads when the magazines are largely funded by advertising dollars from the companies that make the products that the magazine reviews? I'm not saying there's some grand conspiracy, but Pop Photog writing a negative review of the F80 seems a lot like biting the hand that feeds it. That is the advantage that PDN has, and that is why the reviews here are not redundant. Of course, if we're asking for loaners we might be in a similar situation, but there are ways around that.

Mr. Miller... I think Mr. Atkins has rather a different point. Some of these shortcomings seem not to be problems with specific camera models, but rather problems with the universe as we know it (i.e., 6, 8, 15, 18 to name the most obvious). In place of 18 one might as well simply say that if the camera is pointed randomly, it's probably not looking at something you want to take a picture of. Some of the other comments are more about cameras, but I still wouldn't want every review to mention that the camera in question cannot meter with the mirror locked up, just as I don't want to be reading that a certain SLR body won't iron my shirts for me. It would be a nice feature, but so far no bodies have it so it's not much of a review issue (more of a "send a letter to Nikon/Canon R&D" issue).

 

I think it's great if reviews mention a few obvious oversights on the part of the designers, but those should probably be restricted to features often available on other units (i.e., mirror lockup).

Now, I don't want to prattle on about bias, because I don't think it's a MAJOR problem in reviewing (though something to think about, always), but I must respectfully disagree with Philip. Yes, people complain about their houses and cars... and I am the first to admit that, if I had the money, I would likely buy a Leica system and leave my Nikon stuff at home (yes, equipment is equipment... but the simplicity and quality are so appealing). That said, I still think you'd get a more objective review out of me by dropping some kit in my lap and asking me to wander around shooting with it for a couple of weeks than you would by asking me to review my own stuff. For starters... I picked my stuff over the other stuff out there (of course, this could be a useful bias in a review, since readers might be able to determine if they have the same shooting interests as you). And I stick to my story that many people are hesitant to admit to themselves that they may have wasted money... especially on stuff purchased recently (it's easier to say "I was so dumb" than "I am so dumb"). And Bob A. has a point: some people on pdn are, with respect to equipment, exactly like the 13 year old boy (and some are stuck in phase 2).

 

Is bias a critical factor in a review? I guess if people write reviews well it isn't. The guidelines posted are certainly a leap in the right direction. So, Mr. Greenspun... how might I get involved?

Mr. Atkins, do you think it would be possible to borrow something for that long from Nikon, Canon, or any of the big producers (I'm actually asking, not rhetorizing). The problem is that, if it isn't, you're only going to get reviews by owners of the equipment. And my psyc. major girlfriend tells me that it is well established that people will give favourable feedback on products that they have spent a lot of money on (to avoid feeling like chumps who threw money away). Just look at the Nikon/Canon debate here on pdn. Is one really so much better than the other in ANY area that someone would get so worked up about it? I think most of the flame wars stem from the fact that people have invested a great deal in these systems.