Hi all,

Recently I bought the X-Rite 810 densitometer from a bankrupt’s estate. The machine is in good working order but it came without the manual and reflection plaque (PN 302-12) and a transmission film (PN 810-68) that are needed to calibrate it.

I think I need (at least I want to) to calibrate the machine and I don’t have the calibration plaque and film. Is there any way to do it without the original plauqeu and film? Or do I have to buy them, which I think would cost me more than I payed for the densitometer?

I will not meassure color, just B/W transmission in order to find my EI according to the Zone-system. There are som buttons and modes and I just can’t figure out how to do. Can anyone shed some light?

For instance, the second button on the left dials between Read-Green-Blue, Autocolor and Visual. What should i choose for b/w film?

Next button switshes between density and HD-LD. What is HD-LD and which one should i use?

I haven’t found a way to reset the readings, is there any?

I got the machine without the manual, is there anyone available that is downloadable?

Best regards

Erik Sundström Europe/Sweden

PS. I post this question in rec.photo.equipment.large-format, photo.net and LUSENET B&W Photo - Film & Processing if they adress different readers.

-- Erik Sundström (erik.sundstrom@kau.se), January 24, 2002

Answers

I have the 820, not the 810, so I can only help with the general questions.

Although a real calibration plague would be best, you can probably get by with a home made calibration standard. You will need a white patch, and a dark grey (almost black) patch, which you will then need to read on another calibrated densitometer. The dark patch should be in the range of 1.80.

A transmission patch would be a little harder to make, and I can't locate one to see what typical values are used.

Visual will give you the reading for black and white (at least I think that is correct).

HD-LD is useful for plotting contrast; it takes two readings, and gives you the difference. It is useful for plotting professional control strips (where this is one of the values plotted), but for your use, I don't think you will need to use it. Just write down the readings you get, and do any calculations needed.

Good Luck, David Carper

-- David Carper (david.carper@ilford.com), January 25, 2002.

Check with Darkroom Innovations / The View Camera Store http://www.darkroom-innovations.com/ and ask Fred about making you a "calibrated" step wedge. He did this for me a few years ago.

He copied a calibrated step wedge onto 4x5 TP, then read the densities with his freshly-calibrated densitometer and noted them. It was around $30 or so compared to double or more that.

I know that errors could creep in by doing it this way, but it's far better than nothing and probably better than an uncalibrated step wedge.

Otoh, if you could get ahold of a step wedge perhaps you could get the people at your local photo lab to read and note the densities for you.

No idea about the reflection mode; although I have the proper placque I've never had the urge to get into that.

-- John Hicks (jhicks31@bellsouth.net), January 25, 2002.

Hi, Erik; you absolutely need to use some kind of calibration; here's something you can do. You WILL need to know actual density values of a test target; the easiest way is to have someone with a known calibrated machine to read it for you. It won't be as good as a first generation test plaque, but ought to be adequate for what you're intending.

For transmission, develop a piece of B&W film to a density of about 3.0 (this is really dark and typical of an X-rite calibration patch). Maybe collect some old pieces of film leader (that was fully developed). There is a good likelihood that some will be close to this density. Ask a pro lab, etc, to read a few test strips for you. You will want these to be using the "visual" response. If you want to also calibrate the RGB channels, you could ask them to also read these; they ought to be pretty close to the visual number.

Once you have a piece of film close to 3.0 density, get your machine in 'T' (transmission) mode by pressing the "T/R" button. Then press "CAL". When it says "calibrate NO YES", press the button below "YES" (it's the "CAL" button). It will then display "T V:Hi = " something. Use the buttons under the up/down arrows until it reads the same as the "visual" density of your calibration strip. Then press the button under "V:Hi" (it's "COLOR") to cycle progressively through R, G and B. Put in the appropriate numbers; if you don't have color numbers, use the same visual density number. Finally, it will ask you to read "…NO FILM" followed by reading "…STD:HI", which is your calibration strip.

Your transmission mode should now be calibrated. To double check, with no film it should read 0.00 +/= 0.01 or so. The film patch should now read whatever value you entered in as the value. PS: I checked the settable limits of one particular machine; it could be set anywhere from 1.50 to 3.50; however, as I said before, X-Rite seems to generally use about 3.0.

The reflection mode works in a similar manner, except that you will need a "white" patch. I would personally use a piece of glossy photo paper; both a bare white and a "nearly black" patch. The typical X-Rite check plaque had a "black" patch density of about 1.80.

Have fun with your new machine. If any further questions, feel free to email!

-- Bill C (bcarriel@cpicorp.com), January 28, 2002.

Thank you all for your input! I will test above mentioned suggestions during upcoming weekend. Hopefully it will work out, otherwise I will come back, or get in contact with the Swedish importer. Thanks all.

Erik

-- Erik Sundström (erik.sundstrom@kau.se), January 29, 2002.

You can download the manual fro http://www.xrite.com/products/product.asp?Show=Literature&id=43

Ernie

-- Ernest Gajdusek (wme_eg@ix.netcom.com), March 06, 2002.