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Discussion Starter · #1 ·
ok so im reading howstuffworks.com about hdtv resolutions and i come across a cool little chart of what hdtv resolutions should be it kinda looks like this:


The formats used in HDTV are:

720p - 1280x720 pixels progressive


1080i - 1920x1080 pixels interlaced


1080p - 1920x1080 pixels progressive


it gets me to thinking about my purchase i hope to make soon of either a 50hdx82 or a 51s500 (which by the way do yall think is the better tv anyway, just between the two though since it has taken me weeks to narrow it down. please dont throw in another choice and confuse me :) ) and im thinking hey they really dont tell you the horizontal resolution?


so i look around for 5+ hours and finally find out that the hitachi has 1280 horizontal lines and the toshiba 1600 (the hitachi info i found on their site and the toshiba info i found on cnet)...hey im getting jipped!! i thought a real hdtv has to have 1920x1080 not 1600 x 1080 or 1280x1080??!!!


man so im kinda pissed can someone explain to me why this is?? did anyone else notice this? Thanks for any insight.
 

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Basically, it's because CRTs are analog, and as such are only capable of resolving so many lines of resolution per inch of CRT. Most of the CRT RPTVs out there use 7" guns, which can resolve approximately 1200-1280 lines of resolution.


I looked up the Toshiba and it has new features that say it'll make the picture 20% sharper with its PowerFocus CRTs and that their PowerFocus HCF lenses will make the picture 40% sharper. Just for grins, do the math and figure a 40% increase from 1200 lines of resolution is 1680 lines. I haven't found any documents that specify *exactly* 1600 lines for the Toshiba, but I suppose it's possible they've found a way to get 1600 lines out of 7" CRTs, though on the face of it it sounds more like marketing than anything else.


To wit, I found this on Toshiba's online glossary:

Quote:
Powerfocus™HD Optic System : The PowerFocus™ HD 6-Element Lens System is an exclusive new lens system designed specifically for HDTV. Most lens systems cannot faithfully reproduce a high-definition signal. PowerFocus™ HD utilizes six elements, advanced lens design, and a peerless color-correction system to produce an image that is up to 65% sharper than an image produced by standard lens systems. In addition to the benefits of Toshiba PowerFocus™ CRTs (Cathode Ray Tubes), this year’s improved PowerFocus™ HD CRTs utilize numerous image-enhancing advancements, including a higher beam current and finer beam spot, for a 30% increase in sharpness and a 10% increase in brightness over standard CRTs. These advanced CRTs, now on all of our integrated HDTV and HDTV-Compatible models, produce a 20% focus improvement over last year’s models. The new PowerFocus™ HD Optic System enables Toshiba 50", 55", and 61" Cinema Series® HD models to take advantage of crystal-clear HDTV signals, producing up to 1280 lines horizontal resolution.
So take that for what it's worth, but it sounds like you'll resolve about the same amount on either television.


Hope this help! :)


Rick
 

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Made a stab at summarizing this question recently , so no need to type it again. Basically, the format for 1080i is 1920 horizontal pixels width for each of 1080 lines.


But you have to consider just when these 1920 pixels are resolvable , as outlined in this link. HDTV sources aren't delivering such resolvable detail due to many factors, including the limiting resolution of cameras (~1780 horizontal pixels), tape recorders used, or MPEG-2 encoders used at stations. Early approval tests of the HDTV standard showed these results for test patterns. But simple patterns put virtually no strain on the delivery system, so motion-video images carry less detail than these test results.


A review of an earlier Mitsubishi RPTV using 9-inch CRTs indicated it resolved 1600 horizontal pixels, but the consensus seems to be that 7-inch-CRT RPTVs can't. -- John
 

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Discussion Starter · #4 ·
thank you so much ive been looking really hard for that info. so i guess i should really just buy what looks good to me. well guys which one?

50hdx82 or 51s500


ive been torturing myself for to long and just want to buy a tv now so ill let you guys decide. help a tired brother out...:(
 

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hitachi is better quality than toshiba
 
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