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Output Of LCD Projectors

On a upcoming job, I will be shooting two figures against the projection of a LCD projector on a projection screen. I am researching the output of various projectors to find which have the greatest output in lumens or footcandles.

Has anyone used a particular projector available that has a strong output? Has anyone run across a web page that compares the outputs?

I am shooting 200 ASA film with at least a 1 stop compensation for filter and want to make sure I have enough on the screen.

Thanks,

Sean Kirby

Sean Kirby
Director of Photography
Blue Eye Films


>I am researching the output of various projectors

Sean,

I shot a feature last year that involved shooting people in front of LCD projected images against various backgrounds. I wound up using a projector with a 4000 lumen output. With my 500 ASA films, it was more than enough light...maybe even too much, as sometimes the projected image was a little too blown out. I'd say somewhere between 3000-4000 lumens is a good bet.

Hope this helps

Ken Glassing
LA Based
OP/Dp


Look into a Barco projector.

A G5 will start you out at about 5000 lumens at 1024x768 or better depending on what you feed it (up to 1600). If that is not enough you can go up to a Performer R12 or G10 which can run between 8 and 10,000 lumens of light at 1600x1200, more than enough light and detail.

With projectors I like to look not just at output but clarity. Barco is one of the leading projector companies in the world in that arena.

Walter Graff
BlueSky Media, Inc.
www.bluesky-web.com
Offices in NYC and Amherst Mass.


We've had good luck shooting 30i HD with a Sony 700 with an iPaq MP3800 display in the background. Distance from camera to screen was about 25 feet. Using the 45K filter and pushing the white balance up a bit gave a nice slight contrast between the 56K projector image and flesh tones lit with tungsten lighting with 1/2 and 3/4 CTB. The producer liked the look, so everyone was happy.

The MP3800 gave us a high f4 on pure whites. We were projecting B/W stills from a laptop. I haven't worked with a video projection in this scenario. I hope you can make the translation from my HD numbers to film.

The MP3800 literature claims 1300 lumens. Your mileage may vary. Usual disclaimers.

Peter Tubbs
HD Videographer
Des Moines


Walter Graff writes:

>With projectors I like to look not just at output but clarity.

Video Systems magazine recently did an article about prosumer-level video projectors. They warned that many lower-end units were quoting brightness figures that represented centre-screen brightness...and that in order to jack up that figure, uniformity was being sacrificed (read : significant hot spots). How far into the high end this practice goes one can't say... but the appropriate application of a spotmeter or video zebras would be in order if you're planning to shoot off the screen.

Dan Drasin
Producer/DP
Marin County, CA


>Video Systems magazine recently did an article about prosumer-level >video projectors. They warned that many lower-end units were quoting >brightness

Bottom line Dan is that the numbers they get for projectors is about as reliable as the numbers manufacturers use for cameras. 1000 lumens sounds great but add a video signal that is using 1/4 of the luminance and you soon learn that you need about 5000 lumens to make an image on a projected screen to read properly with film or video cameras.

Walter Graff
BlueSky Media, Inc.


The other issue with most published ANSI Lumens ratings is that they are usually best case, "fresh out of the box". The lamps used lose light output with age.

John Pytlak
Eastman Kodak Company


Walter Graff writes :

>you need about 5000 lumens to make an image on a projected screen >to read properly with film or video cameras.

With what kind of screen?

Dan Drasin
Producer/DP
Marin County, CA


Thanks for all the input.

After a bunch of research, I set-up an appointment with a local audio visual company to test with my SLR at the same ASA/shutter speed. I am going to go through a number of projectors with different lumen values to find the best one.

If I discover anything interesting, I will be sure to post it.

I love the Barca idea, but the rental cost was frowned upon by the producer.

Sean Kirby
Director of Photography
Blue Eye Films


Good call by going to a rental house for testing.

It's really something you have to see to get the correct picture for. I have an association with Staging Techniques and they are a great company to call when you nee dot do
such tests.

Walter Graff
BlueSky Media, Inc.



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