Best thermometer

What thermometers do you guys use, can you get any from dollar stores? I was thinking of using an aquarium one, any good? Getting ready to develop my own BW film, just need thermometer and some photoflo, and some plastic jugs, debating which jugs to use as well. My powder D76 makes a gallon, as well as fixer, Thanks

Don't see why an aquarium one shouldn't work if it lets you read 68F. I use the cheapest B&H had in stock and it's been working fine for me. Especially if you are testing to find your own developing times the acuracy of the thermometer matters less than the consistency. As long you are at the same reading each time you're set.

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have some preferences stated, and advice that you might find useful.

Lee

Picked up 2 from Lee Valley (sort of a Canadian L.L Bean) for $8.00 each. Stay away from the photo suppliers.....too much $$$$$$.
Can you imagine a store charging $19.75 for a film can opener????? I use my trusty Moosehead Beer church key.

Mike

It depends on how much measuring you do. I don't even bother checking the temperature because I use jugs of distilled water that are room temperature, and rodinal isn't that temperature sensitive.
If I was a fanatic for exact temperatures I would probably get a good thermocouple thermometer since they equilbrate faster. It depends on what you mean by good.

As for the jugs, just get a gallon of distilled water from the food store. Costs you 99 cents, you get a jug and you don't have to worry about water quality. They aren't light tight so put your solution in a box or cabinet.

finny99 said:

What thermometers do you guys use, can you get any from dollar stores? I was thinking of using an aquarium one, any good? Getting ready to develop my own BW film, just need thermometer and some photoflo, and some plastic jugs, debating which jugs to use as well. My powder D76 makes a gallon, as well as fixer, Thanks

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Thanks guys, yea just wondering if I can store in a dark gallon jug for oxidizing and stuff, I really dont want to have to use 4 1 litre bottles too much storage, was thinking of laundry detergent jug, they come in dark colors

Like avandesande says, any bottle stored in the dark works as well as a dark boottle in the light. Plastic soft drink bottles come in a variety of sizes, and are great for splitting up your mixed developer into smaller lots. Gallon milk jugs are great for keeping wash water at room temperature. If you can keep your film tanks, chemicals, and wash water at a room temperature between 65 and 75 degrees F, a wall thermometer with a fairly expanded scale works fine. If you shop at a Dollar Store, compare several thermometers and reject any that don't match the others. I do keep an accurate photo thermometer to check other thermometers by. For B&W it's not the absolute temperature, but consistancy in temperature, that counts.

Thanks guys cant wait to get going on this, was bringing my rolls to a pro lab, he does good work, but to develop and scan 2 rolls the other day cost me $ 34 Canadian !! not to mention the roll cost as well

For my 8' sink I use a little digital thermometer that has its sensor on the end of a 3' wire. I picked it up a an aquarium store for about $8. I poke it through a little hole near the end of the hose I fill my sink with and it responds fast enough that I can adjust to a temperature in a minute or so. It reads to 1/10 a degree and crosschecks with my more expensive photo thermometer. Temperature in my sink is held in place by a 250W plastic aquarium heater, and two small aquarium powerheads to circulate the water around. Works like a charm.

I bought a Kodak Process theometer 20-25 years ago. They are accurate and rugged. Maybe able to find one cheap used.

In B&W it's consistency AND accuracy that is important.

Well, it's the materials too. Developers do not all have the same conversion according to temperature.

In Michigan, my darkroom is stable during the summer, and NOT stable during the winter. And 63 to 67 is a BIG difference with Rodinal; catastrophic with other developers.

A good thermometer is about the cheapest investment you can make: there is a world of difference between a Weston dial thermometer and a cheapo dial, and there is a huge difference in electronic thermometers as well. My Westons ($40 list) are dead on and 15 years old. The $20 substitutes are seldom accurate NOR consistent. Linearity is nice too.

A Kodak Process Thermometer is good to keep as reference.

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I use my Fluke multimeter with a temprature probe. Accurate to a tenth.

With thermometers one must distinguish between acuracy at different points, linearity between the points (to interpolate) and readability. In most of our photo processing we use a few "standard" temperatures. The most important ones are probably: 20C 24C 38C. The 20C points tend to be for "room temperature" processes and so are "as designed" more tolerant to less than exacting temperature while the higher temperature tend to be critical--- most "less than ideal" E-6 processing tends to be a factor of inacurate temperature control.

Most all "affordable" digital lab thermometers are "calibrated" (if they are calibrated and most are not) against two points, a low temperature and a high. The electronics of latest generation digital thermometers are reasonably linear (but not really) and so it works out. Acuracy however is significantly lower than readability. Few of these (and none of the affordable ones) are calibrated against a traceable NIST/DIN/ISO source and so even their points of highest acuracy might not be the same as those of another thermometer. The electronics are susceptible to ambient temperature ranges and so despite high readability and perhaps a calibration (at a given temperature) to a good source they are not as repeatable as one might hope (and many assume).

Mercury lab thermometers have very linear response, don't wear (YES electronic thermometers show signs of wear) and are not effected much by ambient temperature. "Good" thermometers are calibrated by hand to multiple points against traceable ISO sources. They are, by contrast, not as readable.

The Kodak Process Thermometer is excellent and offers traceable accuracy at ALL our process temperatures but is not very readable. They are usefull to tell if one is within tolerance of a given temperature (which must be in 1/2C) but are almost useless to tell the temperature to any resolution much better than 1/4C or so. They are suitable for "process control".

When this is important there are precision thermometers available that can read a limited range but can do this to 1/10C or better readability. They are very delicate so not really something for "everyday" use. I use these to calibrate by electronic thermometers and processors.

For a thermometer I use the Kodak Process one. I've had it for 30+ years and never had a problem. Go to your local pharmacy and ask if they have any empty 1 gallon jugs. Most liquid medicines are supplied this way and the jugs are mostly dark brown glass. Perfect for photography. Usually they just throw them away so you can probably get them for free or very cheap.

I use a digital thermometer used by health inspectors for food testing. I have found it to be quite accurate when checked against a lab mercury thermometer. Picked one up for about $10 in a restaurant supply store. Display is selectable between C and F and reads to tenths of a degree.

I can get you a Delta #! at my local camera shop for $12.00 (no tax).

Mike

Mike Kennedy said:

I can get you a Delta #! at my local camera shop for $12.00 (no tax).

Mike

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With respect, not a notoriously good product.

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I'll agree with df on this one.

Here ya go:
http://www.bhphotovideo.com/bnh/con...299&is=REG&addedTroughType=categoryNavigation

Weston make two, a large dial and a small: same price.

The large is easier to read, but takes a little longer because it goes slowly as it gets close to the temp.

The small is faster to settle, but not quite as easy to read.

Coin toss: great tools.

d

I bought the Kaiser thermometer linked below two years ago and love it! One can get an accurate reading of a liquid mixture's true temperature within seconds. I use it with my graduates when I mix developers and have never had a problem with it.

http://www.bhphotovideo.com/bnh/con...ls&Q=&sku=86715&is=REG&addedTroughType=search

I just used a dollar store one, and did two rolls, looks like it worked pretty good