Film-Tech Forum ARCHIVE: Which Colorimeter?

This is topic Which Colorimeter? in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Simon Taylor (Member # 6029) on 01-03-2011, 02:03 PM:

Hi All. We are busy here in New Zealand installing NEC series 2 projectors with Doremi servers. As part of the DCI Compliance, we are required to colour calibrate the screens. There is limited to no supply of instruments here in NZ. The contenders look to be Minolta CS-100a (looks easy to use), Photo Research PR-650(expensive) and Ultra Stereo(don't know)
Questions;
What colorimeter would you recommend and who can sell us one?
How do you keep it within calibration; against coloured plates, or do you return the unit to the manufacturer?
Cheers for now
Simon

Posted by Steve Guttag (Member # 268) on 01-03-2011, 02:26 PM:

I have had little to no trouble with the USL PCA-100. As for calibration, we send it back to USL annually. In fact, if you don't keep your meter calibrated, it doesn't matter how much you spend on it...if it isn't calibrated, it is just spewing numbers.

Note too, BACP is now making a filter wheel for the PCA-100 so you can have both the Dolby filters and a polarizing filter already loaded. You just turn the wheel to put which filter (or none) in front of the lens.

-Steve

Posted by Ed Mauger (Member # 4813) on 01-03-2011, 07:25 PM:

Hi Simon,
The PhotoResearch PR655 is very stable, reliable and the most accurate of them all (and most expensive!), but not hugely more than the others. There's a dealer in Australia - check http://www.photoresearch.com/current/contactasia.asp#lightlab

As for the Minolta CS100A, have a look at the specifications. It seems that it will not measure x,y co-ordinates below 12cd/m2 (about 3.5fL), so this would be useless for cinema projectors, particularly for low light 3D colours.
You could try the Minolta CS200 instead. This time there's a dealer in New Zealand!:
http://www.konicaminolta.com/instruments/about/network/asia.html

One problem with the CS200 might be the lack of accuracy of x,y measurements at low light levels of +/- 0.004. The DCI specs call for +/-0.002 for review rooms or +/-0.006 for theatres. Depends if you're bothered about that or not.

The other 2 are:
USL PCA100 (as in the post above), or
Jeti Specbos 1211 http://www.jeti.com/cms/index.php/instruments/radiometer/specbos-1211
[I'm pretty sure this is the correct model - but check before!!].

I know of a few people who have the Specbos and are very happy with it, and the same for the PCA100 and CS200.

Not sure what you'd do about calibration - maybe the Australian and New Zealand agents can calibrate the PR655 or CS200.

Good luck!
Ed.

Posted by Jussi Siponen (Member # 5572) on 01-04-2011, 02:16 PM:

I don't have the unit on hand, but I think we're using the Jeti Specbos 1201. At least "Calibration of cinema projectors" is listed as one of the applications.

Pros: dirt cheap (relatively speaking) [Big Grin]

Cons: reguires a computer, slow

Posted by Gordon McLeod (Member # 33) on 01-05-2011, 08:36 AM:

some people are using this meter
http://www.sencore.com/products/Optical-Tri-Stimulus-Color-Analyzer-OTC1000_182.html

Posted by Chase Taylor (Member # 778) on 01-05-2011, 08:17 PM:

I use the USL PCA-100 and love it!

I got the filter wheel from BACP also, if you are setting up Dolby 3D using a Doremi Server it is a must. I just wish I could figure out how to make it turn remotely, maybe a servo or something?

Posted by Simon Taylor (Member # 6029) on 01-07-2011, 02:05 PM:

Thank you all for your very good advice. Will see if there are calibration services here or is Aus for any of them.
Kind regards,
Simon