Project looks better on CRT than HD LCD?

[Cliff Vaughn]

I'm downconverting from HD 720p to SD for DVD distrib. I've got latest FCP, Compressor and DVDSP. I've monkeyed with exporting a native 1280x720, then Compressing using Best 90 min, then into DVDSP. I also tried exporting a 10-bit SD file, then going straight to DVDSP. I aim to keep 16x9 using letterbox.

Basically, these various methods and variations look good on computer and even in the DVDSP simulator. They're even fine when burned and viewed on a CRT set. But they look pretty bad when viewed on an HD LCD screen (no matter the pic size/format).

What gives?

[Glenn Chan]

Does other equivalent material look good on the HD LCD? Do other DVDs look good?

Can you be more specific about how it looks bad? (Though that may be difficult to describe in words.)

[Bill Davis]

I don't think there's anything strange about this.

Putting work created for one raster (NTSC-SD) on another raster (HD at 720p or 1080i) is nearly always a recipe for an image looking bad.

A good 50% of the broadcast content I watch on my various HD LCD screens looks pretty terrible.

It simply a fact that when you map a picture to a resolution OTHER than it's native resolution, you tend to get crappy results.

Think of it this way. Your SD raster is composed of squares that we'll imagine have an edge length of 1 inch.

Now you want to take those 1 inch squares and place them on a grid composed of squares that are only 2 fifths of an inch long (your HD display) Since the SD squares are NOT evenly divisible by the underlying HD squares - what you're left with is a pretty good recipe for an ugly display.

One you can see every day if you watch SD cable TV signals on an HD television display - as many of us do daily.

It's not pretty. But it's the inevitable result of transcoding between resolutions during your workflow.

That's ALWAYS something to avoid if possible. Cuz every time you transcode between non-evenly divisible rasters, you WILL make the picture worse.

And it will be that way throughout the transition between the SD and HD video standards.

[Cliff Vaughn]

I agree that a lot of SD content I watch on my HD displays has artifacts, rough edges, etc. It's just that my test DVDs so far seem significantly worse than other DVDs or broadcast signals I watch on the same display.

The main degradation I notice on my test DVDs is really jagged lines (and it's mostly a talking head in front of a bookcase at this point).

So ... since my images seem worse than others on these displays (though my images look very good rendered and even on a CRT), I figured there must be some setting that would improve them for HD displays.

Thanks for your responses.

[Chris Swanberg]

This seems like a good place to ask. I have a SonyZ1, and can shoot in HD or DVCam. If the current end product is intended to be in SD, am I better off to shoot in DVCam then? I had always assumed shooting in HD and saving the HD content for possible later use and downrezing to SD would work well, and give me the best possible SD picture - at LEAST equal to DVCam? Not so?

[Carl Middleton]

Chris,

I don't think the answer is quite so simple. Both have advantages and disadvantages.

With DVCam - I frame codec, so each frame is created separately. Lower resolution. Uncompressed audio.

HDV - Long-GOP codec. Fast motion will give you macroblocking, and make the video painful to watch. Higher resolution, so lower motion video will look more stunning. Keep in mind that there can be an AREA of high motion, think in terms of percent. if 30% of the screen is moving quickly, that's not so bad. Do a quick pan, and prepare to wince. :) Audio is compressed, albeit high quality compression. Good for dialogue, but not for foleys or other sound work.

There's plenty more to be said on both! It depends on the job, but personally, I shoot HDV for archival purposes. I think the results are well suited to documentary/advert dealer tags/interviews and the like that play a major role in my business.

C

[Chris Swanberg]

Carl - thanks for that informative answer. One more if I might... which in your experience (if either) image will look better overall (assuming the original image was shot acceptably, eg. no macroblocking in the HD image for example) DVCam shot images, or downconverted HD to SD images?

[Andy Wilkinson]

Originally Posted by Cliff Vaughn

The main degradation I notice on my test DVDs is really jagged lines (and it's mostly a talking head in front of a bookcase at this point).

Just a thought. Did you somehow put a field order into your editing down to SD for your DVD or not? This sounds to me like it MIGHT be an interlace "combing" (what I call "venetian blind") effect, i.e. lots of almost sawtooth edges to hard vertical lines....like books end on in a bookcase????

This is often a problem with 1080i HDV > SD, but in your case you started out with progressive (720) so I don't know if this is relvant or not.

[Carl Middleton]

I personally love HD images. I prefer them, even on an SD screen. I can definitely tell the difference!

As long as there's no fast motion likely to cause macroblocking, or extremely detailed audio (i.e. music) I would always shoot HD. It's just prettier. =)

[Ervin Farkas]

Originally Posted by Bill Davis

I don't think there's anything strange about this. Putting work created for one raster (NTSC-SD) on another raster (HD at 720p or 1080i) is nearly always a recipe for an image looking bad. A good 50% of the broadcast content I watch on my various HD LCD screens looks pretty terrible. It simply a fact that when you map a picture to a resolution OTHER than it's native resolution, you tend to get crappy results, etc...

I'm afraid that's an over-statement. My 37" Mitsubishi LCD ("full HD, 1920x1080 native) has a much better picture compared to my SD sets, when driven by an SD DVD player via HDMI.