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Discussion Starter · #1 ·
JimP came down to visit yesterday and brought with him an AccuPel signal generator. Pretty neat gadget...



AccuPel link...


He got my Toshiba RPTV looking much better as well as my Z4 projector.

I contacted Ovation Software (AVIA) and they are discussing an HD version of AVIA, but nothing scheduled or actually in the works for now.

I wouldn't mind having one of these little jiggymadoo's but $1300 is not chump change and I don't really got it right now.

I checked around a little but haven't seen anything near this price. Are there any cheaper signal generators out there that I might be missing?

I'll probably end up waiting on AVIA or DVE, although DVE's site appears to be down... not sure what their plans are for a new calibration DVD.
 

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Okay, I have real weakness for gadgets like this. A signal gen is only half of the equation, what did you guys use for the other half Sonnie? I went trolling around on their web site and it looked like a new toy but I don't know if I would be able to use it. :scratchhead:

-john
 

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Discussion Starter · #3 ·
Hey john,

I'm not sure I follow you. We had some filters to view through. There was something that JimP mentioned about the grayscale being more exact if he had something with him that he didn't have, but I can't remember what it was. I'm not realy technically savvy with this stuff. I learned quite a bit with Jim, but then there was a lot I didn't really understand.
 

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A spectraradiometer, basically a device that will accurately measure the display and interpet the results scientifically.

Problem is that low cost solution don't work well with the ultra high pressure mercury bulbs that are typically used in LCD and DLP based projectors.

The professional devices run something in the range of $5K to $7K and require a periodic calibration. I've heard of calibrationist who didn't know that they had to have them calibrated, yet noticed that their calibrations always seemed a bit blue.

Another approach which is stupid simple is to use one of the $125 ish puck solutions to calibrate a CRT computer monitor. They are especially accurate on CRT displays. Display a split grayscale on your computer(jpeg file found on the internet) and a similar one through DVE onto your display(unless your willing to spend for the Accupel). Then its basically an exercise of making the two match. So for grayscale calibration, you are very likely to get a pretty good adjustment. One of the little known secrets is that the human eye is very sensitive to slight differences in color and more accurate at lower IREs than many of the devices that are marketed for display calibrations.
 

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The filters I used over at Sonny's were related to getting color saturation and tint adjusted off of the blue signal. (used the color bar pattern of of the Accupel. Ideally, you also want to adjust color saturation and tint off of green and red as well, provided you can find the settings which are usually burried in the service menu. I use some special filters that kodak makes to better see how the display is responding. The ones that come with Avia and DVE leak some, especially the green one (leaks blue).
 

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JimP said:
The filters I used over at Sonny's were related to getting color saturation and tint adjusted off of the blue signal. (used the color bar pattern of of the Accupel. Ideally, you also want to adjust color saturation and tint off of green and red as well, provided you can find the settings which are usually burried in the service menu. I use some special filters that kodak makes to better see how the display is responding. The ones that come with Avia and DVE leak some, especially the green one (leaks blue).
JP, are those Kodak filters available for retail sale? Do you know where I could get them, and what to ask for?

Thanks.
 

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Joe,

The filters are available from bhphotovideo.com.

The problem is that I wrote the filter numbers on the plastic case I keep them in with a permanent market that subsequently wiped off. I'll try to reconstruct the filter numbers and get back with you.

As a practical matter, the avia filters should work fine. The filters that come with DVE are a bit dark and harder to use because of that.
 

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Well Sonnie it looks like we're getting you closer towards a caibration:devil:

You might want to checkout ebay, I toyed with the idea of buying a Sencore signal generator and found a few coming up - but they are not everyday items so you have to be patient.

NB
Can you send Jim up to Pittsburgh?
 

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Discussion Starter · #11 ·
I think Jim is headed up close to your way here pretty soon... maybe he could swing by.

I haven't thought about ebay for a signal generator... I'll have to keep my eye open there.
 

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Just around the corner in Alexandria Virginia. How far is that??

Been digging around trying to get those filter numbers. Tossed my junk room, folders, emails, etc. Somebody is going to owe me a steak for this. :)

Here they are, drum roll please.

92 Red B&H No. K09233 http://www.bhphotovideo.com/bnh/con...ls&Q=&sku=26574&is=REG&addedTroughType=search $57.95

99 Green B&H No. K09933 http://www.bhphotovideo.com/bnh/con...ls&Q=&sku=26577&is=REG&addedTroughType=search $24.95

98 Blue B&H No. K 09833 http://www.bhphotovideo.com/bnh/con...ls&Q=&sku=26574&is=REG&addedTroughType=search $57.95

Also order the plastic frames as these are gel filters you don't want to be holding them in your hand.

Note that some of these filters are out of stock and will have to be ordered.
 

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JimP said:
Joe,

The filters are available from bhphotovideo.com.

The problem is that I wrote the filter numbers on the plastic case I keep them in with a permanent market that subsequently wiped off. I'll try to reconstruct the filter numbers and get back with you.

As a practical matter, the avia filters should work fine. The filters that come with DVE are a bit dark and harder to use because of that.
Thanks Jim,
After comparing, I see what you mean about the Avia/DVE difference (Until now I hadn't really looked at the Avia filters. I had only used the DVE filters with both DVD's). If they're larger and not too expensive, it'd still be nice to get the Kodak ones. Thanks for your help.

Joe
 

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A 25b filter doesn't filter the same wavelengths as a 98 Blue.

Those frame are a bit pricey. Seems like what I got were the Cokin frames that are a little smaller than a 3x3 filter. I had to trim the gel filters down a little.

Don't know why the Green is less than half the price of the others. Since the other two are out of stock, B&H might just be trying to get rid of them.

Something to think about. If you can't get into you color decoder to make adjustments, there's not much point in having anything other than the blue filter which allows you to adjust color saturation and tint based on the blue signal in the user menu.
 

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Signal generator - someone makes a little USB dongle that generates HDTV test signals, its around $100 or so. I can't recall where I saw it hopefully someone might know? It was a website or maybe ebay?
 

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Okay, I keep seeing this nifty new gadgets to display various test paterns. ISF classes are quite pricey though. Where does one find out what all the mumbo jumbo means? I don't have 2K to take a class. Any ideas? Even if I don't do any tweeking (just had my set calibrated) I would still like to learn about it.

Thanks much
-john
 
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