Due to my dual input Iiyama 22" CRT dying under my hands 2 weeks ago I had a chance of comparing the two. (Setup is 2 computers - one allround and one CAD-specific both connected to the same screen - where I switch monitor input and keyboard to work on either one).
I've worked for years on CRT, all day at the job site and anything between 2 and 6 hours at night for private business, without eye trouble. Prerequisite for this isimage quality. This is both the monitor itself - should be top quality, sharp, stableandclear allover - and the video card being able to deliver high resolution at high refresh rates.
At present I work a 17" TFT alongside a 19"CRT, both delivering about the same real viewing surface.
What bothers me in the TFT is how it handles fine details. Characters on the screen are not identical, depending on the amount of pixels they get to be displayed. The same goes for thin lines : some get one pixel, some get two, some just disappear between two screen pixels. This is due to the difference in technology. On a CRT a pixel just sits there, waiting for the electron beam to activate it (all or partly). Since it's only a reactive surface any part of it can emit light, meaning the bottom half can be lit while the top half is dark. A TFT pixel works on an all or nothing base. It gets instructed a certain transparency level and then all of the surface is set to this level. This explains why TFT only works fine on native screen resolution while CRT accepts any resolution, even higher than available through the actual dot pitch.
How this technology difference translates in real life ? Takea thin vertical line, one pixel wide, situated in the middle between two pixels. On a CRT this line will actually try to hit the middle causing screen dots going dark to light from left to right and vice versa. A TFT will turn both pixels left and right to half brightness because each gets half a line to display.
The other thing is viewing angle. I'm sitting rather close to the screen and notice quite some difference in appearance depending on where on the screen I'm looking. Lines at the bottom even tend to get a kind of 'reverse video' effect. But this can be due to the TFT-quality, maybe it's a limited viewing angle type.
Anyway I ordered a new CRT, until TFT gets to an acceptable level (quality and pricewise).
So regarding the original question. I would certainly not go for a 17" inch since it's just too small for a decent resolution (you'll get 1280x1024 max). And if the option 19" TFT is open I'd rather spend the money on a 22" CRT. I regard 1600x1200 resolution necessary for comfortable working.
Alex
Edited by: AHA-D
