CRTs, LCDs…what’s the deal…

[Todd Terry]

[filmapprentice] “I always thought tube CRTs were better at color representation”

Good assumption…

I will steer clear of commenting on any specific makes and models of either (since there are way-smarter-than-me techie gurus on the COW who are much better suited for that than me)… but up until relatively recently if you wanted a production monitor that you could accurately calibrate you had to go with a CRT.

Now, that is changing. Now if you want to go with a non-CRT (LCD or whatever) it is possible to find some of the very high-end ones that can be calibrated.

As for….

[filmapprentice] “we would also like to know what the actual home viewer would see”

…well, that’s a crapshoot. You can never know what the actual home viewer would see, you can only strive for what the actual home viewer should see… because your average home viewer’s TV from Wal-Mart is not calibrated, and God only knows how it is set up. Look at the wall of TV sets in Best Buy or Circuit City sometime… they’re all showing the same thing, but every one of them looks different. Sadly, that’s the same with home viewers. Best you can do is give them a picture delivered to their set that looks as good as humanly possible… and hope for the best!

T2

__________________________________
Todd Terry
Creative Director
Fantastic Plastic Entertainment, Inc.
fantasticplastic.com

[George Simeonidis]

Thanks Todd, I appreciate the honesty. Smart comment on striving for what the home viewer should see.

[Todd] “…it is possible to find some of the very high-end ones that can be calibrated.”

I’m assuming by really high-end ones we’d be stepping way out of my budgetary bounds…this is why that Decklink HD Pro add-on appealed to me.

From your personal experience, would you at this point in time, stick with the tube CRTs?

[Todd Terry]

[filmapprentice] “at this point in time, stick with the tube CRTs?”

Well, I can only speak for me… but yes in our shop all of the actual production monitors are CRTs. I hate the fact that they are big and klunky and take up so much real estate… but they look good.

You might track down one of the more techie-heads in some of the other forums (Bob Zelin comes to mind, a cranky old guy, but there’s nothing technical that he doesn’t know) and get a more technical recommendation rather than my fairly aesthetic one. You can find those guys haunting the High-End HD, HDV, and RED Camera forums and the like.

T2

__________________________________
Todd Terry
Creative Director
Fantastic Plastic Entertainment, Inc.
fantasticplastic.com

[George Simeonidis]

Great!

Thanks Todd!

[Tim Kolb]

Hmmm…not sure I’d be classified as “old” necessarily, but I’m certainly cranky.

CRTs happen to be the displays that we all know the most about and to an extent, our normal way of technically “doing business” with video in the past has fit hand-in-glove with CRTs as they’ve complimented our human visual system rather well.

LCDs are a bit different than CRTs as once you move to HD, technically no CRT that any of us could even afford a loan for can actually show us all the pixels in an HD picture. Our perception of CRT “sharpness” has as much or more to do with things like contrast than actual resolution at HD frame sizes.

LCDs do not have light-emitting phosphors like CRTs or Plasmas (I don’t recommend plasma displays for any production use BTW). LCDs have a backlight system and an LCD is named after the “Liquid Crystals” that act as valves, blocking or passing light as current is applied to them. For this reason, LCDs have historically not had as “black” blacks as a CRT as an LCD could try to block the light completely by completely closing, but like window blinds, even when they are completely closed, it’s impossible to block all the light and some leaks out. This problem is exacerbated by the bulk of users who simply have the brightness cranked way too high an an LCD that they adjust by “eyeball”. A CRT which has light-emitting phosphors (instead of light-transmitting crystals) has dark blacks because when the phosphors are off, they’re simply off.

Calibration is an issue. LCDs can be calibrated, but for post, you’re typically going to get best results from doing the calibration from a probe and having a high-end display card (something like a PNY NVIDIA 4500 or better) create a “LUT” or look up table inside your computer to control the LCD’s calibration as opposed to attempting a hand adjustment. If you have an LCD driven via DVI or, in the case of a 30″ display, a dual-link DVI, usually the display card will have more precise adjustment capability than the monitor itself.

If you are running an LCD via HDSDI, like the JVC monitor, then calibration is done on the monitor itself…higher end LCDs like the Cine-Tal and the E-Cinema can load look up table files directly so that in addition to calibration you can preview color correction looks, etc.

I’m not all that impressed with Plasmas generally…they look very vibrant for digital signage and tradeshow applications certainly and have a wider viewing angle than an LCD as they are a phosphor-based, light emitting display (that “layer” of liquid crystal “valves” has some Z depth, which is why the angle of viewing on an LCD is more limited). The downside is that a Plasma is a true, digital, display technology. I’m not referring to analog component vs HDSDI here, I’m talking about how the display itself works, not the incoming signal. The plasma’s pixels have no continuous grayscale as they have no brightness range. They are ‘on’ or ‘off’. To fool our brains into believing that there is grayscale, the pixels flash on and off at various rates and our brains simply take an average. While the blacks on a Plasma are “blacker” than an LCD, as the ‘flashing’ rate gets slower and slower to represent darker and darker grayscales, our ability to discern differences between those flashing rates decreases, making details in the darker area of the picture a bit mucky to the human viewer, even though they certainly are dark.

TimK,
Director, Consultant
Kolb Productions,

Creative Cow Host,
Author/Trainer
http://www.focalpress.com
http://www.classondemand.net

[Steve Putnicki]

Tim,
Thanks for the great explanation.