Film-Tech Forum ARCHIVE: Exciter to Red Light Reader installation question?

This is topic Exciter to Red Light Reader installation question? in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Stephen Frazza (Member # 2320) on 02-24-2005, 02:15 PM:

If was to install a BACP RSTR 2000 in place of a exciter bulb and how the test film to do it but had to wait a few days for a RTA to align it would it be ok? Would there be any drastic EQ change needed or could you get through a weeekend. If there was any big change is there anything you could do in the meantime?

It is on a simplex 5 star and a Dolby CP 55.

Posted by Brad Miller (Member # 2) on 02-24-2005, 02:51 PM:

If you are saying you DO have all of the test films AND an oscilloscope and you had an cyan print that required the upgrade for this weekend (just making sure), then yeah you could make it passable. Just do everything else and don't touch the slit loss controls on the preamp card.

Posted by Michael Schaffer (Member # 1204) on 02-24-2005, 04:42 PM:

If you listen to the pink noise very carefully and adjust the lens for the "brightest sound", you should be able to find a somewhat OK focus position. Based on my experience with this equipment configuration, you only need about 1 1/2 turn of the HF adjustment on the preamp card. Eventually you will need far less slit loss correction than with the exciter based system. But like Brad said, it may still be best if you leave the HF adjustment where it is now, because just by "earballing" it, you won't be able to adjust it that precisely.
You can also download a software RTA like this here (free trial) http://www.soft32.com/download_79429.html .
Yes, it won't be very true because it is unlikely that your sound card input is anywhere near flat, but it can help find you the relatively best focus position at least. The BACP readers can be focused to yield a very good HF response with little HF adjustment.

Posted by Sam D. Chavez (Member # 1841) on 02-24-2005, 09:57 PM:

Azimuth is the most critical adjustment and can be "faked" by putting the cinema processor in a stereo format and setting the monitor to a surround only channel. Listen for a null as you twist the entire reader while running pink noise film.

Posted by Darren Briggs (Member # 1071) on 02-25-2005, 02:14 AM:

If your using a scope you can set the azimuth correctly anyway using the x/y button. Also Focus adjustment can be seen in x/y to get the best clear line on the scope.
Listening to the Pink Noise whilst doing the azimuth and focus i find helps.
Final focus tweaks can be don on the RTA.