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Discussion Starter · #1 ·
I'm fairly familiar with calibration as it relates to flat panel displays.

In the next few days, I'll be calibrating a couple of new projectors at the church I attend.

They'll be setup as rear projection (not front projection) and output around 8,000 lumens each pre calibration. Screens are each 12' wide. The sanctuary has enough window light that deep blacks aren't going to happen. These projectors are Panasonic DLPs PT-DW830ULK.

It would seem that back in the rooms where the projectors are located, I'd just aim my colorimeter at the screen at such an angle where its not measuring the shadow it cast. Otherwise, calibration would be as what you'd normally do.

Am I on the right track and what other considerations should be made.
 

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It would seem that back in the rooms where the projectors are located, I'd just aim my colorimeter at the screen at such an angle where its not measuring the shadow it cast. Otherwise, calibration would be as what you'd normally do.
Haven't calibrated any rear projectors myself, but I would think that you should be taking the measurements from the congregation side, i.e., on the side of the screen opposite to projector.
 

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Discussion Starter · #3 ·
Haven't calibrated any rear projectors myself, but I would think that you should be taking the measurements from the congregation side, i.e., on the side of the screen opposite to projector.
Given the angles and distances involved, if I were to do that I'd have to have some 40' runs of cable and be doing a lot of running back and forth to get a line of sight for the remote control to adjust the projectors.

Trying to find the simplest way to do it as its likely that I'll have to go back as the bulbs age.
 

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Given the angles and distances involved, if I were to do that I'd have to have some 40' runs of cable and be doing a lot of running back and forth to get a line of sight for the remote control to adjust the projectors.

Trying to find the simplest way to do it as its likely that I'll have to go back as the bulbs age.
Hey Jim, go with 2 notebooks, place the notebook with the calibration software and meters connected to the place where you want to measure and use the other notebook to the place where the projectors with controls are located.

Use Teamviewer (select free personal use purpose during installation) to see what the calibration notebook sees, so you will be able to check the calibration notebook measurement results using the screen of your other notebook. (internet connection will be required)

BTW JETI/Photoreseach specto's have meter editions with build-it Bluetooth capable connection, to calibrate digital projectors @ cinemas etc..
 

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Discussion Starter · #5 ·
Hey Jim, go with 2 notebooks, place the notebook with the calibration software and meters connected to the place where you want to measure and use the other notebook to the place where the projectors with controls are located.

Use Teamviewer (select free personal use purpose during installation) to see what the calibration notebook sees, so you will be able to check the calibration notebook measurement results using the screen of your other notebook. (internet connection will be required)

BTW JETI/Photoreseach specto's have meter editions with build-it Bluetooth capable connection, to calibrate digital projectors @ cinemas etc..
Good idea Ted.
I'll run by there to test their wifi from those locations.
 

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Given the angles and distances involved, if I were to do that I'd have to have some 40' runs of cable and be doing a lot of running back and forth to get a line of sight for the remote control to adjust the projectors.

Trying to find the simplest way to do it as its likely that I'll have to go back as the bulbs age.
Here is another possible solution. Have you considered a IR remote extender? Not knowing the setup or how you are feeding source material to the projector, you can have control of the projector and other devices remotely from a distance. Many use this method when calibrating home theatres, where the equipment is stored in another room.

The device sells for about $40.00. I purchased one at Best Buy but you can get them almost anywhere. Here is some "information"
 

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Discussion Starter · #7 ·
Here is another possible solution. Have you considered a IR remote extender? Not knowing the setup or how you are feeding source material to the projector, you can have control of the projector and other devices remotely from a distance. Many use this method when calibrating home theatres, where the equipment is stored in another room.

The device sells for about $40.00. I purchased one at Best Buy but you can get them almost anywhere. Here is some "information"
I think I have one of those in storage. There's 12' between the projectors and their respective screens. I wonder how close I have to get the receiving end to the projector.

Seems that these projectors are network capable but I don't know if they'll have that feature in use. That might also be an option. Seems like they'd have to in order to turn them on/off.
 

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I think I have one of those in storage. There's 12' between the projectors and their respective screens. I wonder how close I have to get the receiving end to the projector.

Seems that these projectors are network capable but I don't know if they'll have that feature in use. That might also be an option. Seems like they'd have to in order to turn them on/off.
Again, I have not seen the job site. I have a couple of these devices. One I keep in the tool arsenal, another I have setup for my audio system for outside. The audio system is stored in the garage and the distance (on an average) is around 75'. The only trouble I have noted is that sometimes I have to shield the transmitting unit from the sun light, as it seems to diminish or interfere the remote's signal; other then that it works flawlessly.

I assume that you will be calibrating one projector at a time. It would be interesting to know what type of input feed they are using. Are you going to put the signal generator or DVD player by the projector? Since the remote extender's IR probes come with dual setup this will be no problem. If you need more IR probe to be attached use a "Y" adapter. As for, " I wonder how close I have to get the receiving end to the projector", I would say three feet and the unit will need a power source.

I have used this device in many calibration setups, in some cases I had to revert back down to selecting the pattern screens manually and after using a signal generator that runs in auto mode this almost seem cumbersome.

Good luck with the job, let us know how it went.
 

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Discussion Starter · #9 ·
I went by there this morning and this is the plan.

Put the pattern generator up in the enclosure feeding HDMI to the projector. Run an ethernet from the pattern generator to the laptop located in the auditorium. Position the K10 on a tall light stand in front of the screens. Use an extension USB cable from K10 to computer. Use the web interface on ipad to make adjustments to the projector.

Here's a photo of the construction work where they're closing in the top part of a 4:3 screen to make it a 16:9 screen. Each of these are 12' wide and a tad over 6' tall.
 

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I've done a few church PJs, though they were front projection so not able to handle ambient light very well. The thing I've learned is these high lumen PJs only put out those light output numbers with a very heavily green white balance. Trying to calibrate to D65 can really cut down the light output on them, and they usually need all the light they can get in these environments.

Just to give an example, at my own church we have 2 Panasonic PJs projecting onto perhaps 10' wide screens. In Dynamic mode, they crush whites like crazy, have a very low gamma, and have a very green white balance. I measured them with my Jeti, which has a very narrow FOV, so I set it up along the line of sight from the congregation area. I believe they put out something over 65 fL in Dynamic. I took green down some, not enough to reach D65, but enough to look reasonably good, and chose a fairly low gamma preset (around 1.9) and eliminated white crush. I ended up with something like 56 fL, and I thought it was going to be good... Unfortunately, the calibrated image was then deemed too dim (or lacking in excitement) and they went back to dynamic mode.

Lesson learned: go bright, bright, bright! Maybe pay more attention to focus and resolution than hitting D65.

They use them for a mixture of mostly power point type presentations with lots of text along with occasional videos. The text and graphics generally have lots of 100% levels, especially white, maybe not so much in between where gamma would play a bigger role... So crushing whites won't really matter so much if most everything's at 100% any way. Videos look horrible now, but unfortunately I have to live with it.
 

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Discussion Starter · #11 ·
They use them for a mixture of mostly power point type presentations with lots of text along with occasional videos. The text and graphics generally have lots of 100% levels, especially white, maybe not so much in between where gamma would play a bigger role... So crushing whites won't really matter so much if most everything's at 100% any way. Videos look horrible now, but unfortunately I have to live with it.
Hi Chad,

Thanks for joining into the discussion.

Your description above is identical to the content for this system.

If you were to describe in foot lamberts the peak brightness I should target, what would it be?

My thinking here is to white balance it as well as possible as long as I can maintain that value.

The specs for these projectors show peak lumens as 8,000. I sure hope that's not with a strong green shift.
 

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Discussion Starter · #13 ·
Is the RP screen material designed to soak up ambient light?
I don't know. They're reusing the existing 4:3 screens and they've had those for 7 to 10 years. If rear projection screen material that soaks up light is a relatively new thing, then it probably isn't.

If important, I can find out but its likely to be Sunday before I know.
 
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