OT: Thoughts on Standard Definition

Ecquillii wrote on 6/16/2007, 6:06 PM

I went to a free movie this afternoon, Captains of the Sky, a war propaganda film shot in the early 40s starring James Cagney. The movie was meant to inspire young people to sign up for the RCAF. The showing was sponsored by a retirement living home here in North Bay that used to be a hotel when part of the movie was shot locally (the stars stayed there). The theatre where it was shown was an old movie theatre that has been converted to an arts centre that now shows movies only occasionally. Anyway, the movie was on DVD, projected onto a regular-sized screen (4:3 of course). I was amazed at the quality of the picture—the resolution was the equal to 35mm movies that I saw shown on the same screen in the past. The fall down was on brightness, everything looked a little muddy or dark unless it was in bright daylight. A couple of months ago I saw the animated short The Danish Poet in a regular movie theatre, also from a DVD, with the same surprise about how good it looked. I’m thinking standard definition is pretty good. Just need to get more light on that screen.

Tim Robertson

Comments

RalphM wrote on 6/16/2007, 6:40 PM

Tim, while I'm not sure about the effect of light levels on the perception of SD versus HD, SD is perfectly acceptable for a very large percentage of the viewing public.

As I remember, about 30 - 40% in focus groups did not perceive a significant difference between SD and HD. The other variable that should be examined, though, is whether SD viewed on a run-of-the-mill SD TV and HD viewed on a mid range HD TV would get the same result. (I'm suspecting that the focus groups used a high quality SD TV)

farss wrote on 6/16/2007, 9:38 PM

I've shown more SD video in cinemas than I care to remember. It can be quite acceptable. As you noted you need a decent projector, especially if the source was film. SD DV on the other hand holds up better when you're short of lumens.
On the other hand SD DV printed to film looks like crud.
I have no technical explaination for this but SD video on a big screen projected from DV looks fine as does 35mm (obviously) from a film projector but trying to convert one to the other and put it on a big screen and the results can be woefull.
The other thing to be carefull of is extrapolating this into modern cinemas where the viewing angle is bigger, that's when the lack of resolution really starts to show, especially with 16:9 and beyond.

Bob.

Patryk Rebisz wrote on 6/17/2007, 1:31 PM

Interestingly there is another side to it. SD fooatge shown on HD TV looks like crap while on regular SD monitor it looks great.

Jay Gladwell wrote on 6/17/2007, 2:35 PM

Patryk, it's interesting that you should say that. I've seen some SD footage on a HDTV that looked downright stunning.

I guess it all goes back to the quality of the original, doesn't it?

GlennChan wrote on 6/17/2007, 3:16 PM

Perceived sharpness depends on a number of factors... one big factor is the contrast ratio achieved by the projector. This can be more important than actual resolution.

Unsharp masking can also help things a little.
http://www.cambridgeincolour.com/tutorials/sharpness.htm

Viewing angle also affects things... if the viewing angle is too low, there is little benefit to higher (actual) resolution.

DataMeister wrote on 6/17/2007, 8:57 PM

And viewing distance is a third factor to quality perception. At 30-40 feet away, the human eye can't tell the difference between a single SD pixel that is 3mm wide or three HD pixels that equal the same.

farss wrote on 6/18/2007, 5:42 AM

Well I kind of noticed this today. Playing out directly from a Z1 over HD component and SD composite into a Bravia there's quite a difference but playing out from a PD170 there's a much bigger difference.

Laurence wrote on 6/18/2007, 8:15 AM

My experience is that how good SD looks on an HD monitor depends a lot on the uprezzing and the format of the SD video. 24p or 30p video seems to uprez really well whereas 60i footage does not. Thus commercial releases can look stunningly good while old projects shot on a older camera such as a PD170 or an XL2 do not.

Jay Gladwell wrote on 6/18/2007, 9:27 AM

... while old projects shot on a older camera such as a PD170 or an XL2 do not.

Sorry, Laurence, I'll have to disagree with that. From what I've seen it (XL2 footage) looks "stunning" like I had said above.

Cameras are like musical instruments. It depends on who's "playing" them.

Laurence wrote on 6/18/2007, 10:17 AM

It also has to do with the uprezzing routines on a given DVD player / HD TV combination. Almost all setups uprez progressive SD pretty well. Some don't uprezz 60i SD at all, others do almost as good a job on 60i as they do on progressive.