My Oppo 970HD front projector says that it can accept input signals up to 1080p/24. The 24 Hz rate is much lower than the 50 or 60 Hz of 720p, but it's still comparable to film, so I guess it should look good, right?

Here's what I'd like to know: is this the standard rate for 1080p, or are there higher rates used as well?

thanks,
Bruce

1080p can be any refresh rate. We're used to 60Hz because that's what our TV's operate at. Our TV's are that way because our electrical service operates at in North America. In Europe, electricity is distributed at 50Hz, which is why PAL video is based on 50Hz refresh rates. Film is shot and projected at 24 frames per second. HD-DVD and Blu-ray video is being encoded at 1080p/24, if I remember correctly, although players that support output at 1080p/24 have been hard to find (if they offer 1080p, they generally force a 3-2 pulldown to get the video to 1080p/60). You may be hard pressed to find a source that will provide 1080p/24.

What projector are you using?

Ha ha! I identified my DVD player for you didn't I? I forget which is which sometimes! My projector is the Panasonic PT-AE900U. I never paid attention to its 1080p capability because I didn't expect to have a 1080p source any time soon. But now that I've seen some 1080p Blu-Ray and HD-DVD players' output ... whoo ... that's pretty tempting!

I take it those players I've seen were probably putting out 1080p/60? Seems odd that they'd use 3:2 pull-down if the native encoding was already at a 24fps rate and there are devices that can handle that. Wouldn't the best image come from projecting at the same rate at which the content was encoded?

Yep - oddly enough, the HD-DVD and Blu-ray players (those that offer 1080p of any sort) have generally only been doing 1080p/60 even though the source material is 1080p/24. Since most of the displays we're using are built to operate at 60fps anyway it makes a certain sense, but it is odd that there isn't at least an option for it. I suspect that later generations will start to offer this.

1080P is aweome. I will be buying the Sony KDS55a2000 1080p LCOS HDTV hopefully soon. This is a full 1080P HDTV. I have the Denon 3930CI DVD with the aweome video chip that upconverts DVD to 1080P.

IMHO, 1080p looks good, but only if the screen size/viewing distance ratio is correct. We recently compared the 50" Pioneer Elite 1080p plasma to the 42" 720p Elite display, and found that we could not notice much difference at our viewing distance of about 7-8 feet. The retailer also felt that unless you have a larger sized display, 1080p's detail would be lost at normal viewing distances.

Display size has a lot to do with it. When I was deciding which Oppo model to purchase they recommended the 1080i model for screen sizes under 50".

I was reading an article on the subject of 1080p just this morning. It was posted on Secrets in the last day or so: 1080p: Why You Should Be Concerned . The basic premise is interesting. First, HD video is shot at 1080p/24 (either as film at 24fps with the individual frames subsequently scanned in or as digital video done at 1080p/24 to match film), which can be converted to 1080i/60 for broadcast very simply. They present the case that our 1080i HD broadcasts are technically 1080p/24 (with only an "easy" deinterlacing step required to get that 1080p/24 back), and since the only displays that can natively display interlaced video are CRT's (which the article declares dead technology, and even though I was watching an HD CRT just last night I have to say they're right) it makes sense to opt for 1080p where possible. Not such a concern for me, since my display won't accept higher than 1080i and actually operates "natively" at that resolution, but it's definitely an interesting read.

Gonk -- Thanks for the link; very interesting reading. What I found most interesting was that after spending so much time arguing the importance of 1080p, Secrets says in the end, "Of course, you don't need to have a 1080p display to have a great image. In fact, we're happy to concede that in most cases, with most material, there are many variables, starting from basic calibration, the environment (your room), yada yada, that are far more important than having a real 1080p display." I guess I come down to own a set whose picture and features you enjoy, since you will go broke trying to keep up with every change in technology.

BTW, besides our plasma, we also have an HD CRT (Sony XBR700) that we plan on using for many more years, so in our household CRT is not yet dead, either.

Hi Gonk:

First thanks for your intro to HT on your webpage. It's the best I have found on the net and reference often when I need to brushup on the terms. I do have a few questions?

>480i: 480 lines, interlaced. This is the resolution used by most standard definition television. It is also the native video resolution for DVD. >

Why was 480i picked as the number of lines? Was it the best they could do at the time? Why did they decide on Interlace and not pregessive, again was this just a technical problem?

>Converting between film's 24 frames per second and the 60 frames per second of progressive scan video introduces an odd issue:<
I am surprised that film has not adapted a higher frames per second rate? Why didn't film use a 30 Frames per sec like TV did at the time?

Does a CRT TV actually use all 480 lines of resolution? I thought I read somewhere that SD analog TV singnal would use less then 480 where as a standard DVD would use more of the 480 lines. The VHS format somewhere in between??

>720p: 720 lines, progressive scan. Now we are at HD resolution. 720p is the threshold for HDTV.<
How do lines translate to pixels. For example, can the height of one line on an LCD TV be composed of more then 1 Pixel?

Even though a LCD excepts a 1080I input, does it refresh it on the screen painting the Odd lines and then the Even lines or is it done all at once?

Thanks Bob