Why HD to SD?

[Tyson Yoder]

I have noticed alot of people on here capturing in HD then have to convert it to SD. I use a Sony FX7 and use Sony Vegas Pro 9 to edit. I import HD footage, edit, and burn it on a DVD and get a nice picture. Is there something im missing or why do other people have to go through so much other stuff to get a nice picture on a regular DVD?

[Edward Troxel]

Honestly, I do the same thing. Drop HD on the timeline, render to SD MPEG2, and burn that to DVD. I think Vegas does a great job with that process.

[Greg Fiske]

To deliver both blurays and DVD's. I was surprised how many people are not delivering blurays...

[John Rofrano]

I think it has a lot to do with the format you start with. Like both of you, I just edit the HDV footage from my Sony HVR-Z1U and output using the default SD DVD Widescreen templates and the results are stunning. Absolutely beautiful quality.

I see a lot of XDCAM owners (Sony EX1/EX3) complaining about how bad their footage looks when output to SD. I assume it's something to do with that format. Maybe the AVCHD shooters have the same problem? For my money, nothing beats HDV for ease of editing and beautiful output in both HD and SD.

~jr

[Bruce Phung]

Originally Posted by Tyson Yoder

I have noticed alot of people on here capturing in HD then have to convert it to SD. I use a Sony FX7 and use Sony Vegas Pro 9 to edit. I import HD footage, edit, and burn it on a DVD and get a nice picture. Is there something im missing or why do other people have to go through so much other stuff to get a nice picture on a regular DVD?

Year ago, I dropped the HD to Vegas timeline, edited, rendered it for DVDA to make a DVD. The quality at first I was happy I thought it was good. After much reading on the forum and decided to try the HD-SD downconversion, the resulted is VERY VERY good. You will definately see the different in quality.

[Randall Leong]

Originally Posted by John Rofrano

I think it has a lot to do with the format you start with. Like both of you, I just edit the HDV footage from my Sony HVR-Z1U and output using the default SD DVD Widescreen templates and the results are stunning. Absolutely beautiful quality.

I see a lot of XDCAM owners (Sony EX1/EX3) complaining about how bad their footage looks when output to SD. I assume it's something to do with that format. Maybe the AVCHD shooters have the same problem? For my money, nothing beats HDV for ease of editing and beautiful output in both HD and SD.

The horizontal resolution and the pixel aspect ratio (PAR) of the source also affect the downconversion quality. The HDV format is only 1440x1080, with a PAR of 1.3333:1 anamorphic. Widescreen SD is 704/720x480 with a PAR of 1.2121:1 anamorphic. The PAR of both is close enough to allow a good downconversion from HD to SD.

XDCAM and many AVCHD videos, on the other hand, have a resolution of 1920x1080 with a PAR of 1:1 (square pixels). This is significantly more difficult to downconvert properly to non-square-pixel SD - and Vegas alone does a poor job of this particular downconversion, with the resulting downconversion ending up being full of artifacts.

[Kevin Lewis]

Tyson: I've always wondered the same thing. I frequently use Pinnacle Studio twelve which is not as robust as vegas and I get great results by simply importing HDV and exporting to a DVD. I've actually been amazed at just how good the quality is.

[Randall Leong]

Originally Posted by Kevin Lewis

Tyson: I've always wondered the same thing. I frequently use Pinnacle Studio twelve which is not as robust as vegas and I get great results by simply importing HDV and exporting to a DVD. I've actually been amazed at just how good the quality is.

See my post above yours:

The Pixel Aspect Ratio (PAR) of widescreen SD and HDV are close enough to one another -- anamorphic. Square-pixel HD is significantly more difficult to properly downconvert to widescreen SD.

[Ken Jarstad]

Originally Posted by Randall Leong

The horizontal resolution and the pixel aspect ratio (PAR) of the source also affect the downconversion quality. The HDV format is only 1440x1080, with a PAR of 1.3333:1 anamorphic. Widescreen SD is 704/720x480 with a PAR of 1.2121:1 anamorphic. The PAR of both is close enough to allow a good downconversion from HD to SD.

XDCAM and many AVCHD videos, on the other hand, have a resolution of 1920x1080 with a PAR of 1:1 (square pixels). This is significantly more difficult to downconvert properly to non-square-pixel SD - and Vegas alone does a poor job of this particular downconversion, with the resulting downconversion ending up being full of artifacts.

Oooooooooh! So that's it. I always wondered about the seemingly endless topics about HD to SD quality and wondered if I was really missing something. I have made dozens of DVDs from my HDV footage and they always looked great. Many times the picture, like good quality studio DVDs, looks almost high definition on a decent upscaling player. I hope my HV20 lasts a long time. Long live HDV!

[Jeff Harper]

I agree strongly with all that has been said, AVCHD is much more trouble, HDV much easier to work with. I'm now working with AVCHD and it adds up to lots of time and disc space.

[Leslie Wand]

thankfully it's only client avchd files i work with - though i occasionally use one of their cameras as a 2nd if needed.

i soon learnt that even though my i7/920 will happily play it, it makes life a lot easier to transcode avchd to .mxf in most circumstances.

having done that i, like may others here, simply use the tools available in vegas and dvd arch to produce what i consider good looking pics.

i'll even qualify that by adding i've played around with almost everything that's been mention, eg. handbrake, et al, and to be perfectly honest (pal 50i), whatever difference there might be, it's totally lost on the client - and for the most part even on my own observations.

i know everyone wants the BEST picture possible, but really, get a life - the client ISN'T going to see any difference between the workflow above and/or however many extra hoops you jump through to 'improve' the quality.

that said, i'm talking strictly hdv @ 50i.

[Chris Harding]

Just for interest my little DuoCore struggles with previewing AVCHD so what I do is use Upshift (from VAAST and NewBlue) to transcode the files down to HDV MPEG2 at 50mbps and Vegas loves the format!!

I also get Upshift to make any interlaced video progressive so I can just work with the HDV file in Vegas and not have to worry about de-interlacing. Remarkably enough the HDV file seems to my eyes, to look a lot sharper than the original MTS file too!!!

It does add to your workflow time but the result is pretty good!!!

Leslie??? what is the advantage of transcoding to MXF????

Chris

[Jeff Harper]

I don't know Leslie, my AVCHD files look pretty bad when not trascoded first, but maybe your editing program resizes and interlaces better than mine does.

[Randall Leong]

Originally Posted by Jeff Harper

I don't know Leslie, my AVCHD files look pretty bad when not trascoded first, but maybe your editing program resizes and interlaces better than mine does.

Not only that, but even high-bitrate MPEG-2 videos at 1920x1080 look horrible when not transcoded first (I get severe artifacts). Most NLEs, including Vegas, do a poor job of resizing videos that have a given PAR to another video that has a completely different PAR. It's not just HDV versus AVCHD, it's also the matter of PAR. Downsizing square-pixel HD to rectangular-pixel SD often requires special resize alogarithms in order to do this properly. The only reason why (16:9 widescreen) SD made from HDV looks relatively good is that the PAR of both formats are close to one another.

[Leslie Wand]

well, i haven't done any raw avchd editing in ages, and i can't really remember how, or if the pics looked degraded at the end of the day.

remember i'm in pal land and from what i gather we're slightly better off picturewise to start with ;-)

i used mxf after reading on a number of ng's (incl. scs) that, as an alternative to buying a codec, such as cineform, using sony's own was working and holding up well for a lot of people compared to transcoding to hdv - so i went along with that. i can't compare it to cineform since i don't use it, but afaic my end product looks as good as my source (hdv), and the dvd's produced within vegas look incredibly good.