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View Full Version : The ins and outs of used densitometers



Steve McL
02-23-2010, 03:25 AM
Hi,

I wonder if some could comment about the ins and outs of buying a used densitometer please? I'd like to know whether they last a lifetime or whether they need parts regularly. I'd like to know whether the calibration bits and pieces are really needed and whether they are readily available (or worth their cost). It seems the XRite brand is very widespread and into other markets also. Are they the ones to go for? Are there any special gotchas involved in buying - are there any tests to run beforehand etc.

I'd like to hear about any other issues you can think of too.

Thanks in advance,

gmikol
02-23-2010, 03:20 PM
About 6 years ago, I picked up a good-condition Eseco Speedmaster TR-90C for $75 on eBay. I've been told that the TR-90's are the only ones that Eseco still supports. X-Rite made a lot of different models, but I don't know enough about any of them to recommend one over the other. X-Rite may be more available outside the US. If you just need B&W your choices expand greatly. If you're doing your own color, and want a color one, there are fewer choices. The TR-90 that I have can do transmissive (film) and reflective (prints), with both Status M (color neg film) and Status A (slides and prints) filters.

The "calibration bits and pieces" are absolutely necessary, in one form or another. You can get suitable calibration references from Stouffer, as well. You can have them (for a price, of course) read the values (in color or B&W) of their strips, and you would then use those values as your calibration targets. Store them carefully, as they may shift with time, temperature, and environmental exposure.

As for tests to try before you buy, bring along an ND filter or 2, and you can read the values of the filter (1 stop = 0.3 density, 2 stops = 0.6, etc.). You'll at least know you're "in the neighborhood", though the calibration might be off by a bit, depending on how long it's been unused. Color is harder, as you have no way of knowing whether the internal color filters have deteriorated unless you have a calibrated reference to compare to.

Hope this helps a bit...

--Greg

Barry S
02-23-2010, 03:31 PM
It seems crazy to buy a new densitometer these days. I spent $30 on mine and the seller told me I was the only person that even called. When I tested it with a calibrated step wedge, it was very accurate. The earliest generation electronic densitometers had circuitry that was more prone to drifting, but if you buy something made in the last 25 years or so, it should be in good shape.

glbeas
02-23-2010, 03:43 PM
Watch for some brands that incorporate a small battery in the circuits to hold the settings when shut down. As they age the battery will go bad and calibrations won't hold. I solved mine by replacing the battery in my Xrite reflection densitometer, it took a pretty thorough disassembly to find and solder in the new cell.

ic-racer
02-23-2010, 06:01 PM
Tobias units were US made and some parts are still available for the older models. New ones are still being made.
I can't speak for the other brands, but the Tobias units are easier to repair than say a hand-held exposure meter or a rollfilm camera.

David A. Goldfarb
02-23-2010, 06:12 PM
I used to have a very old Macbeth densitometer that worked quite well until a capacitor blew up. I tossed it and have been thinking I should pick up one eventually, but one effect of owning a densitometer is that it helps you develop a better sense of what a good neg should look like, so it hasn't been a high priority.

RalphLambrecht
02-23-2010, 06:18 PM
I used to have a very old Macbeth densitometer that worked quite well until a capacitor blew up. I tossed it and have been thinking I should pick up one eventually, but one effect of owning a densitometer is that it helps you develop a better sense of what a good neg should look like, so it hasn't been a high priority.

I don't understand that one. Would this not be a reason to get one? Why the 'but'?

outwest
02-23-2010, 06:39 PM
I paid $10 for my Kodak Color Densitometer. No frills, just works.

Steve McL
02-23-2010, 06:51 PM
Thanks guys,

I thank you for the reference to Stouffer - I was wondering where to get them.

The units also seem to last a while without needing parts. I was afraid that they'd need lamps or some such on a semi-regular basis to stay within tolerances, so it looks good on that front.

Cheers,

jeroldharter
02-23-2010, 07:38 PM
You can get Stouffer step wedges at the View Camera Store, and I believe at Freestyle. I have the 21 step 4x5 step wedge. The various types can be somewhat confusing.

I picked up a used X-Rite 810 densitometer for ~$95. Make sure it comes with the instruction manual and the calibration materials. You would then use the Stouffer step wedge for calibrating film exposure and development.

I recommend that you pick up a copy of Beyond the Zone System by Phil Davis before you get a densitometer. It is a very informative book that I review often.

RalphLambrecht
02-24-2010, 02:14 AM
Thanks guys,

I thank you for the reference to Stouffer - I was wondering where to get them.

The units also seem to last a while without needing parts. I was afraid that they'd need lamps or some such on a semi-regular basis to stay within tolerances, so it looks good on that front.

Cheers,

You can buy Stouffer products from Stouffer directly.

http://www.stouffer.net/

pentaxuser
02-24-2010, 09:22 AM
I don't understand that one. Would this not be a reason to get one? Why the 'but'?

I don't understand this either, Ralph and yet it doesn't seem like a simple typing error such as using the wrong word such as "but".

Maybe the poster will tell us. I am intrigued

pentaxuser

Wayne R. Scott
02-24-2010, 10:41 AM
What I believe David is saying is that if you have not used a denistometer in the past, using one will help you determine what a good negative should look like. In his case he has used one in the past and now knows what a good negative looks like, so in his case he does not feel that he needs to purchase another one.

How's that for a guess as to what he meant?

Wayne




I don't understand this either, Ralph and yet it doesn't seem like a simple typing error such as using the wrong word such as "but".

Maybe the poster will tell us. I am intrigued

pentaxuser

David A. Goldfarb
02-24-2010, 10:55 AM
I don't understand that one. Would this not be a reason to get one? Why the 'but'?

Wayne R. Scott can read my mind. Sorry if that was confusing.

Having worked with a densitometer for a few years I think I'm getting good results and I can pretty much tell what I need to do by inspecting the negs directly and by seeing how they print on paper, and I haven't been testing a lot of unfamiliar materials, so I think I can survive reasonably well without a densitometer at this point.

One of the reasons I think the densitometer and the spot meter became such important tools when Adams, White, Picker and others were promoting the Zone System was that a densitometer made it easier to learn to print from a book, without an experienced teacher to tell you what you could improve and how, and even without access to fine prints as examples. If you could adjust your exposure to get a Zone I density of .1 and your development to get a Zone VIII density of 1.2, you were in the ballpark for most grade 2 enlarging papers, and if you wanted to make grade 3 your target paper or wanted to use a softer or harder enlarging light source, it wasn't rocket science to adjust to the Zone VIII target density a point or two in either direction.

What I think Adams may not have stressed enough is that by using this method and looking at negatives that work and negatives that don't work so well, it is possible to educate one's eye to learn to expose, develop, and print without a densitometer, and even to make judgments about the quality of the light and the reflectance of familiar subjects without a spot meter.

So sometimes I wish I had a densitometer again, mainly for testing new films efficiently, but I also think that I can manage without one.

RalphLambrecht
02-24-2010, 11:05 AM
I agree. I also rely on the densitometer heavily during printing to check highlights and shadows. After a few hours in the darkroom, my judgement is clouded and everything stars to look good, but the densitometer keeps me honest and forces me to stay on track.

Mike Wilde
02-24-2010, 11:10 AM
I have an old macbeth td504 with the colour neg filter set that was gifted to me gratis. It seems to work well enough for my purposes. It orginally came oem with a spare bulb, that mine lacks, I have not bought one. I think that the photomultiplier tube may die first, and if that goes then I will just bin it.

It is very useful to me to see how to deal with batches of long out of date material, when I start to use it for experiments. Then if the experiments on a given lot of old stock are successful, it is used for general purposes, and sometimes even revenue producting projects.

ic-racer
02-24-2010, 03:33 PM
So sometimes I wish I had a densitometer again, mainly for testing new films efficiently, but I also think that I can manage without one.

This is exactly why I got my sensitometers and densitometers back in 2000. I was anticipating a time when one would basically be shooting 'film of the month' as steady supplies of a 'favorite film' will no longer exist.

Now when I'm forced into using an 'unknown' film, I fire off a test strip and I can tell right away its speed relative to my favorite, its response to the developer and see if it has a weirdo film curve.

In fact just last month all my local shop had was Tri-x in 100 foot rolls. I actually had to treat that as an 'unknown.' Looking through my records, the last time I used Tri-x was in 1989!

Oh yea, same for developer. My local shop has been out of the T-max one-gallon jugs for 3 months now and now they don't have any of the smaller jugs either. All I have now is Rodinal which I kept just for my 1:100 experiments. This last month I'm forced to using that at 1:25 for everything (and its really a very good general purpose developer for 120 and bigger). So, I have been putting my testing equipment to good use lately.

BTW, does this mean I don't use the "Massive Development Chart?" Absolutely not! With any test, you need a starting point. So I frequently check that resource for my 'first guess' development time for the test strip.