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  1. #31
    fhovie's Avatar
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    I am amazed - $600 to $2300 for a decent lens and $40 for a balance. Repeatability gives the confidence in technique to free one up from the wonderment of "will it work?" A decent scale has a load cell. Good load cells cost from $50 to $500 ea. Then there is the electronics. If you want to split the range of the load cell into 30,000 accurate divisions with maybe a million internal counts of resolution with compensation for linearity and filtering - I would think that about $600 would be a good figure. I would say that for a scale with both good electronics and a good linear load cell, a minimum of $750 would be in order. Now- calibration .... did you know that the spin of the earth causes gravity to be a little different at each latitude. (something about centrifigal force) Enough to make a plane crash from overloading - as plane weighers require you state your latitude. That means something calibrated in China will likely not be correct in LA. That means you need calibration weights. Oh - yeah -calibration weights cost more that 40 - a lot more! Good thing you can measure these chemicals with a spoon and still make them work. .... well ... at least some of them. If I didn't have the bucks to buy a decent electronic scale, I would at least get a good triple beam balance. Maybe one that has been gone through. They can do an excellent job for about $100 or so.

    OK - I am done ranting now .... just hit a soft spot is all. Sometimes lowest bidder mentality doesn't make the world a better place is all.
    My photos are always without all that distracting color ...

  2. #32
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    Quote Originally Posted by aldevo
    On the other hand, if one is going to be producing a batch of only 1 liter of D-23 or D-76H stock using volumetric means - it's going to be difficult to achieve consistency from batch to batch.
    My viewpoint is that there are two things we should know here. How accurately can I measure, and how accurately must I measure in order to get the results I want. I do not like to feel anxious about something unless I know it's something that warrants anxiety. I have seen formulas that were obviously converted from avoirdupois to metric, and the converter didn't know when to stop the significant figures. Some of my old friends, when they read my article, went out and spent much coin of the realm on analytical balances so they could weigh these ridiculously precisely specified weights. Well, it's all about magic potions, isn't it?

    Now if you who worry about variations of gravity (you don't really, do you?) would get a mass balance instead of a scale, you could eliminate that source of anxiety.

    I can show you from experiments I have done that when it comes to phenidone in a PQ or PC developer, the magic ratio of P to Q or P to C can be anything from 1:40 to 1:80 with no practical difference in activity.

    My first balance was one of the Lyman powder balances. It is sensitive to 1/10 of a grain and was affordable. Larger quantities, like sulfite, are not usually critical so I don't weigh them out unless I want to avoid controversy in something I'm going to publish.
    Gadget Gainer

  3. #33
    Maine-iac's Avatar
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    Quote Originally Posted by gainer
    My viewpoint is that there are two things we should know here. How accurately can I measure, and how accurately must I measure in order to get the results I want.

    I can show you from experiments I have done that when it comes to phenidone in a PQ or PC developer, the magic ratio of P to Q or P to C can be anything from 1:40 to 1:80 with no practical difference in activity.

    I agree completely, Pat. I have a balance scale that I bought more than 25 years ago, and shortly thereafter discovered teaspoon measurements. I've not looked back since, and have never had bad results that I could trace to the measuring system I used. Plenty of bad results from improper exposure and other photographer-specific flubs, but none due to improper measurements.

    Of course, I've stuck with the same set of measuring spoons for all these years, so whatever gram-equivalent I'm really measuring has remained consistent.

    If I get a bottle of Vitamin C that's in crystalline rather than powdered form, I will weigh it to see if my teaspoon amounts need to be adjusted, but rarely has that been the case.

    In fact, since converting to the Phenidone/Vitamin C world of developers, my shelf of other chemicals is slowly moldering away. Life is very simple in the darkroom now with my bottle of powdered Phenidone, bottle of isopropyl alcohol, jar of Kodalk, box of Arm & Hammer Washing soda, box of Borax, and jar of Vitamin C. Oh, and a little Liquid Orthazite for my paper developer. Simple and cheap.

    Larry

  4. #34
    Maine-iac's Avatar
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    Quote Originally Posted by psvensson
    FYI Larry, you can use half as much carbonate for Delta 400. It's counterintuitive that you can use the same volume of carbonate and ascorbic acid, but it works. 10 mins at 74F gives a contrast range of 1.2. The grain is nice, but the accutance isn't exciting.

    Interesting. I never tried the carbonate with Delta 400. Started with metaborate at 6 minutes at 70 F, and it works so well for both grain and accutance that I didn't try the carbonate. I figured it would shorten the development time too much since it's a more active agent.

    I switched to carbonate for Delta 100 and Fuji ACROS and Fuji Neopan, because the metaborate demanded times in the 10 minute range for those films, and I prefer to work with the 6-7 minute range. Even with carbonate, ACROS needs 7:30. But what beautiful tones it has! I shot a contrasty snow scene recently, and barely had to do any burning or dodging. The highlights held beautifully, the shadows were richly detailed, and the midtones glowed.

    Larry

  5. #35
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    With regard to sharpness, as has been pointed out by others, the developer byproducts that ascorbate leaves are acidic. These help give it sharpness, but if the pH is too high, the neutralization of those products might occur before they have a chance to create the effect. I'm just guessing, but it might be worth a little test. Try adding a little borax. I have used half and half borax and carbonate.
    Gadget Gainer

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