The lack of response at the 400 line square is shocking... And from the chroma bars, it looks lie there's about 60 or so lines of color. The lack of cross color on the zone plate is excellent though. Faroudja products always have had low chroma resolution because they use his color bandwidth expansion technique which makes it look like more color resolution than it really is. Like in Faroudja equipped DVD players the vertical chroma resolution is only a single field of 120 lines instead of the full 240 lines DVD is capable of.

wait, how did you figure out how much chroma resolution was in there? Those bars at the bottom all looked colored....

On my screen they only appear to have full color at .5 which is 40 lines, and the 1 MHz bars are much more desaturated with red/orange being the predominant color and and the in between bars are gray - the 1.5 MHz bars look basically gray with only the slightest hint of tint and the color bars in between totally gray with no color tint at all. So, it looks like full resolution extends to maybe 60 lines and drops off after that since NTSC is 80 lines per MHz.

Correct. Since we can still see details when frequency response is down even 6db or more at the top end (they are just softer, less colored or fuzzy) and the quote of 80 horizontal lines per MHz is a close approximation due to the fact that we can see - and hear - frequencies that are not at full level/flat, quoting lines of resolution in an analog video format for color and luma is always an approximation. Now, if only the .5 MHz bars had full color and the others were totally gray, then stating that the color resolution is no more than 40 lines would be totally accurate - and it could be even less if the blue/yellow bars were spread outside their borders. To see what 30 lines of color looks like record that pattern from LaserDisc to VHS. Neither the 1MHz or 1.5MHz bars will have any color at all and the .5 pattern will be fuzzy and smeared.

The SMPTE B/W resolution chart is also an approximation because you have to kinda guess where the lines blend from distinct lines to a total gray background.

BTW, the horizontal lines per MHz for 1080i/P HDTV is 29 lines per MHz and the color is a quarter of that.

Yes, but also for measuring comb filter results on diagonals/patterns that can cause interference between Luma and chroma at those frequencies.

As an interesting side note....
NTSC has an excess of diagonal resolution... More than the human eye needs for the horizontal and vertical resolution standard NTSC has. Some of that can be filtered out and extra color detail or more horizontal detail can be interleaved into it almost invisibly.

Here's a link to an explanation of the chart and all it's features
http://www.snellgroup.com/documents/engineering-guides/testchart.pdf

I've never seen that many vertical bars for the chroma frequency response test.

TLK

Do you mean the .5, 1.0 and 1.5MHz chroma bars? Or do you mean the actual results you have achieved with various comb filters?

Chapter 55 of the THX box set of The Abyss has some extensive chroma response tests, but I've never seen a list of the frequencies that each set of color bars represents. I wish THX would have published a document about each test pattern on the disc - which BTW, is the only THX film to have full-field test patterns. They were used by THX for testing LaserDisc pressing plants and for coming up with the requirements for the THX LaserDisc player certification. Sadly, they never released any info on what kind of performance characteristics they were looking for from a player to achieve certification. To my knowledge only one article/interview with THX ever appeared about the THX LaserDisc player program - and that was in Widescreen Review and it's not very informative. Still, I should scan it and make a PDF for posting.

The Panasonic DMR-E20 has an excellent 3D adaptive comb filter that can be switched to 2D in the setup menu. The comb filter has full 5.5 MHz luminance bandwidth and just about the full 120 lines of chroma resolution, plus an EXCELLENT full frame TBC. Set at its fixed 60 minute 9mbps MPEG-2 rate, it makes beautiful copies of LaserDisc's. Standard Audio recording is Dolby Digital at 224kbps at all video bitrates, and is audibly transparent. It's only drawback is the audio levels are automatically set - there is no manual audio level control. But, I've never encountered any audio compression or problems recording LaserDisc's.

Hello,

Wouldn't it be helpful to start an overview thread of units with good comb filters and/or with the ability to decode NTSC Super Color ? Just like the overview of all units with AC3-RF input?

I think that would support all the LD collectors / fans / otakus to find the right unit for getting decent results instead of trial and error a dozen times.

I have a Toshiba DR430 and it does a great job of upconverting to my Samsung LCD.