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Behind the Numbers: LCD vs. CRT
OrenWolf writes "CNet has an article discussing the difference between CRT's and LCD's - where they've been, where they're going, and what to look for when buying one. They inclde information on how to judge the most important (and most overlooked) features in LCD's, the rise/fall of pixels, something that keeps most gamers away from them." Good
summary type piece, although nothing exceptional for the more hardcore techie.
I hope they are comparing the actual viewable screen size when they are compaing the prices of CRTs to LCD. Most people don't realize this, but a 15" LCD has the same viewable area of a 17" CRT, and a 17.4" LCD has the same viewable area of most 19" CRTs. You can't compare a 15" LCD to 15" CRT, since they really aren't the same size.
Dimensions, Refresh rate, Colors, Response time, and Power consumption.
While I would agree these are all important, why are response time and refresh rate not linked together? I.E., a crappy refresh rate (50Hz) combined with a crappy response rate (60 ms) could possibly lead to trouble. Also missing are contrast and brightness, two more very important aspects.
I dunno what the big deal is about lcd vs. crt. As far as power, the average desktop user(including me) doesn't care. The desk space, perhaps. But I've already adapted to my 21" monitor taking up most of the space, so what's the big change gonna be. I guess just a few more square inches for me to fill up with trash!
A few years back, my CEO's wife said, "We should replace all our monitors with LCD flatscreens to make the whole company look high tech to investors" Eventually that kind of free spending drove the company into the ground.
LCD's are pretty to look at, that's about it. None of them can match the refresh rate of a CRT. (Yes I know LCD's don't really do vertical scan like CRT's do, but most LCD's sample the analog verticle refresh at 60hz then coverts it to digital unless it has a digital interface to begin with)
If you really want to reduce eye strain, or just simply get work done, a bigger monitor with a high refresh rate (120HZ+)
Size and refresh rate are the two most important things for me when I purchase a monitor. I don't care if I can hang it on a wall or off my ass. Unless you absolutely need it to be portable, you're better off using a CRT.
Saying LCDs are bad because you can see JPEG compression artifacts is like saying microscopes are bad because you can see germs in them.
JPEG is lossy compression and always has had artifacting. Because you've never seen it before says more about the blurry monitors you're used to than anything else.
32 bit color == 8bit red, 8 bit green, 8 bit blue, 8 bit alpha mask.
It's the same color content as 24 bit.
One of the "questions and answers" claims that
when purchasing a tube-type (CRT) monitor, "any CRT will do".
I won't bother being graceful here. That's a bunch of crap.
Cheap monitors are junk. The CRT is the major difference between cheap and good-quality monitors. I am typing this on an NEC MultiSync FE950+ which is a beaufiful flat-face CRT monitor. It costs a lot more, but it is worth it. The other two monitors on my desk (a Sun/Sony 20E20 and a Misubishi DiamondTron) are of similar quality. They will last me through several computers...in fact, the Mitsubishi already has.
Umm i think your a little confused. There is a big difference b/w 32bpp and 32bit color depth. Most(all?) consumer level cards max out at 24 bits of color information per pixel. When you set "32bit color" You get 8bits Red, 8bits Green, 8 bits Blue, and 8bits of something else.
What that something else is depends on the card and the drivers. It can be alpha channel, z-buffer, stencil buffer, accum-buffer, or just wasted in order to get better alignment(and to have a bigger number).
Now, that being said high end graphics cards/workstations will let you have higher color depths, I have seen 30bit(10R 10G 10B, and the other 2 bits used for things like multi sampling) and 64(16R 16B 16G) mentioned, although I have not had the luxury of seeing/using these systems myself.
Kevin
Thoughts on tech, Software Engineering, and stuff
I agree - LCDs are cool because you *can* see JPEG compression artifacts. I use a laptop to save/view photos while I'm out of town. The camera can also plug into the TV but the LCD is about 1,000,000,000x better than the shoddy TV picture. I'll take the LCD anyday for viewing photos...
I have wondered though if professional digital photographers will start a demand for tiny CRT monitors. Think of a 5" CRT that can do fairly high resolutions... Just a pipe dream and probably the degree of percision required to get a good picture at high resolution on a CRT plus the market size would make it a no go for any sane person.
But it would be interesting...
Not trying to pick an argument, but some thoughts on your opinion:
"The current generation of LCD displays are terrible for viewing photographs. The square pixels and variable contrast makes for a number of bad artifacts:"
I suspect the problems have as much to do with software being optimized for CRTs as much as real problems with LCDs.
"1. JPEG compression is terribly magnified on an LCD. look at a typical Yahoo News press photo on an LCD and then on a CRT, especially close ups of people."
I would argue that this actually says more about the visual clarity of the LCD, in being able to pick up the artifacts that CRTs blur away.
It's akin to claiming that certain brands of cameras with extra high speed film and extremely good lenses are bad for taking portraits because all of the makeup, flaws, and blemishes show up in the photographs, and that it's better to use a slower film and a less precise lens.
"2. Contrast is variable from top to bottom while looking dead center: On my recent model VAIO laptop, when looking at the screen from dead center, the top is too dark, the bottom is too bright. (in terms of black level)"
It is certainly true that CRTs have a wider viewing angle and more uniform color because each pixel is more like a point light source that radiates in a sphere, where an LCD pixel is a cone of light. Newer LCDs, like Apple 15" and 23" LCDs, have much better contrast ratio, 350:1, better viewing angle, 160 degrees in either dimension, and better brightness, at 200 nits, than their older 22" LCD;300:1 and 180 nits. I can't google anything about the VAIO laptops, but it's not uncommon for, say, a ViewSonic 17" LCD to hit 220 nits and a 300:1 contrast ratio; brighter and more evenly lit, but not nearly as black.
"3. Colors shift depending on left to right viewing angle, and typically subtle hues of red and blues and purples will not appear as pleasing and natural as they do on a CRT."
This does have something to do with the viewing angle; as per the 'pleasing or natural bit', that's about color optimization, I believe. LCDs have a different gamut and visual quality than a CRT, and if the software doesn't take that into account, that's like having overhead flourescent lights on a CRT without a hood!
"4. Overall gamma is poor, with the falloff happening in all the wrong places, which wrecks havok on portraits and figure photography. (which means yes, pr0n!)"
Can't speak for that, you may be right about the gamma.
"So it's interesting to note that on a recent visit to Vertis studios in San Francisco, the people who often do the Macy's catalogs, that each digital photography station consisted of a high end scanning back camera and a macintosh with a 22" LCD monitor! I mentioned this to one of the supervisors and he said "Yea...we're aware of the problems with LCD...we carefully calibrate them and make sure to stare at them dead center, or we get the color shift problem left to right." I figured that someone had sold them on those setups purely for the 'cool' value, and they fell for it hook line and sinker."
No, there are real reasons to use a LCD over a CRT, more than just 'cool' value.
Size, energy output, eyestrain-flicker, digital precision (digital input to digital output, consistent guaranteed visual quality across all LCDs if gamut and color space are taken into account, etc), and visual precision (no convergence, alignment, moire, or focus problems).
LCDs suffer from different problems entirely; instead of moire, convergence, focus, or alignment problems, they suffer from narrower visual focus, and lower contrast ratio and brightness. In fact, LCDs are *much* sharper than just about any CRT because there is no alignment, no convergence, no focus problems because there's no reliance on three electron guns aimed at a phosphor coated screen.
You also have the issue that CRTs aren't linear, where an LCD can be made so. CRT electron guns are nonlinear devices between the 0 and 1 signals, while an LCD's ramp between the totally off and totally on signal *is* linear; I'm talking about the value of Red0-Red255, or Blue0-Blue255, or Green0-Green255.
Then there's refresh. CRTs must refresh a line at a time, where LCDs refresh the whole screen at once; less headache, less flicker, less eyestrain.
"He then took me into the finishing room, where, to my pleasure, there were several workstations outfitted with high end CRT monitors with hoods around them. I knew there was no way they were doing catalog work without CRT's, given the pickiness of fashion retailers over the color accuracy in the catalogs."
This will change when designers and fashion retailers start using LCDs; then when you have digital images end to end, you can start seeing more focus on better compression algorithms (ne horrible JPEG artefacting), better gamma and gamut and color space taking advantage of the fact that LCDs have linear color response and deterministic color response.
"When I was working at Digital Domain in Hollywood, as well as every other VFX company I've ever worked for, there was nigh an LCD in sight, because you can't do critical adjustment on an LCD."
You couldn't do it, doesn't mean you can't. There are problems right now, but doesn't mean there also aren't advantages.
"Despite all this doom and gloom, it IS getting better all the time, and eventually, unless it's replaced by DLP or other "every pixel is a tube" flatscreen technology, then I'll be calibrating my photographs for viewing on LCD, because that's what everyone will have. Until then, I prefer my high end Sony FD trinitron above all else."
Yeah, new technologies and software (such as Apple going all LCD) should help a lot.
GPL Deconstructed
during the last 25 years of working with computer and video screens:
1. Uncalibrated monitors are worthless except for texual information. Might as well be black and white. Hardware calibrated is best. Calibrated by eye with test patterns is better than nothing.
2.) Ambient light is key. Correct light is a source behind the monitor (no other sources) that is roughly (no more than) 20% as bright as the light from the monitor, and has the same color temperature. Refresh is key. Incandescent is best, or match the refresh of flourescent to monitor refresh. One of the best ways to get a headache is standard office setup: overhead flourescents oscillating at a different, subliminally perceived, refresh than the monitor's subliminally perceived refresh. And at a different color temperature. At first, you don't notice, but your brain is going "WTF!?! Are you TRYING to hurt me?!?!"
3.) Trinitrons suck. All inline tubes suck. Triads of dots, not stripes, are best for displaying anything not rectilinear and vertical. Trini's are nice and sharp when looking at office buildings; look at curves (or rotate the office building 14.3 degrees) and your res has just dropped through the floor due to aliasing) As Joe Kane (Google it) said, "When I look at a Trinitron, all I see is stripes".
There's LOTS more. but I'm too drunk and tired. But I've calibrated my TV's since 1990 and my monitors since the first 24 bit display hit the market, and my point is, hardware is the least of it. The least. Anyone who knows what they're doing can make a POS display look better than a zillion dollar unobtainium, proof of concept flim-flam, and with a little homework, you can too. The work's all been done for you (and me, I didn't make this shit up, I learned it). Go find it and use it.
There is a thin line between genius and insanity. I have erased that line. -- Oscar Levant