720 vs. 1080 What's the truth?

There've been many discussions here about this in the last few days.

In brief:

The HVX captures 480i, 480p, 720p, 1080i, and 1080p.

The HVX RECORDS 480i, 720p, and 1080i.

480p and 1080p can be encoded losslessly in a 480i or 1080i stream. When recording, the camera adds extra fields/frames to the stream WITHOUT QUALITY LOSS so it can be read by equipment that only handles interlaced streams (most equipment, that is). This is called "adding pulldown". The Panasonic term for these modes is something like "1080p24 over 60i" "or 480p30 over 60i".

Most NLEs have the facility to "remove pulldown" - take the 480i or 1080i stream and dispose of the extra fields/frames to produce a 480p or 1080p footage WITHOUT QUALITY LOSS.

So, the camera can shoot 1080p. It encodes it "over" a 1080i stream. The NLE captures it and converts it to 1080p without quality loss. 1080p does not lose vertical resolution in this process, and theoretically retains far more vertical and horizontal resolution than 720p.

The interesting issue with the HVX is not all this theoretical 1080p/1080i/720p resolution distinction - indeed, that's all cut and dry and well understood. Rather, the interesting question is how well the other components of the HVX (e.g., sensor, lens) are able to provide enough information to take advantage of the 1080p format. The HVX uses a unique 2-dimensional spatial-offset technique to generate 1080p imagery; it's an interesting question to ask how much better the HVX's 1080p imagery is than its 720p imagery. The broad consensus is that it is somewhat better, but there is not as much of a difference as just looking at the codec specs would indicate - that is, the HVX imager and lens can provide better than 720p resolution, but not quite 1080p. So: 1080 is better if you have the resources for it, but you don't lose as much as you might think by shooting in 720p, and you can gain a lot in terms of variable frame rates and data-rate savings.

In regards to the above-referenced discussion: 1080p most definitely DOES NOT have less resolution than 720p. The 1080p imagery will certainly be at least as good as 720p imagery. General concsensus indicates that HVX 1080p footage has 15-20% higher resolution, and fewer compression artifacts compared to 720p.
 
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Thanks so much to both of you for your detailed replies. I have a project
that I'd like to be able to go to film with next summer and these such strongly
opposing views have been causing me a lot of confusion.

I think that with the bigger sized cards, I would shoot 1080 for my feature
if the image is indeed better and figure out a way (probably more cards!) to
shoot at that data rate. However, I also love the variable frame rates that
I can get with my HVX-200 so I might intercut some footage when I need to
get those shots. I'll have to do some tests but it seems to me that it ought to
blend.

Also, I have a feeling that mixing footage depends on context so when and where
different data rate footage is cut into a project can make a difference.

I am also a big fan of Barry's mantra that aside from the specs., if you shoot and
light well and do all of those things that add production values then you're
going to get a good looking film. The HVX-200 is a great camera but that
doesn't mean that one can forget about production design.

I am fascinated by this 1080 vs. 720 debate because of the practical
ramifications it has for getting the best image when there is the time to do so
and variable frame rates aren't needed. The simple question, which looks
better? is my concern. I do like all the talk about specifications and technology
because it it is fun but primarily I need to know how my entire film is going to be
affected by the one second it takes to switch a menu setting.

Therefore, when I read arguments that are in such disagreement about something
so important, and the people doing the arguing on both sides seem to make a
lot of sense and have good credentials, then I start to wonder what to think.
 
filmtovideo said:
Thanks so much to both of you for your detailed replies. I have a project
that I'd like to be able to go to film with next summer and these such strongly
opposing views have been causing me a lot of confusion.

I think that with the bigger sized cards, I would shoot 1080 for my feature
if the image is indeed better and figure out a way (probably more cards!) to
shoot at that data rate. However, I also love the variable frame rates that
I can get with my HVX-200 so I might intercut some footage when I need to
get those shots. I'll have to do some tests but it seems to me that it ought to
blend.

Also, I have a feeling that mixing footage depends on context so when and where
different data rate footage is cut into a project can make a difference.

I am also a big fan of Barry's mantra that aside from the specs., if you shoot and
light well and do all of those things that add production values then you're
going to get a good looking film. The HVX-200 is a great camera but that
doesn't mean that one can forget about production design.

I am fascinated by this 1080 vs. 720 debate because of the practical
ramifications it has for getting the best image when there is the time to do so
and variable frame rates aren't needed. The simple question, which looks
better? is my concern. I do like all the talk about specifications and technology
because it it is fun but primarily I need to know how my entire film is going to be
affected by the one second it takes to switch a menu setting.

Therefore, when I read arguments that are in such disagreement about something
so important, and the people doing the arguing on both sides seem to make a
lot of sense and have good credentials, then I start to wonder what to think.
Click to expand...

Ive come to the conclusion that shooting with Detial at -7 is the best way to go for film work. you can alway s add your own edge enhancement later, but it leaves you with a nice pretty organic image. Try it in 1080 it looks nice..... then render out a subtly sharpened version. it looks really quite filmic.
 
TimurCivan said:
Ive come to the conclusion that shooting with Detial at -7 is the best way to go for film work. you can alway s add your own edge enhancement later, but it leaves you with a nice pretty organic image. Try it in 1080 it looks nice..... then render out a subtly sharpened version. it looks really quite filmic.
Click to expand...


Terrific info., thank you.

David S., sorry must be the way I posted link but the same link in Hotchkiss's
post works, so rather than me repost I know that one works.
 
ullanta said:
The HVX captures 480i, 480p, 720p, 1080i, and 1080p.

The HVX RECORDS 480i, 720p, and 1080i.
Click to expand...
Correction: the HVX captures at 1080p.

It RECORDS 480i, 720p, and 1080i. But the only way it scans its chips, and the only way it processes the images, is as 1080p.
 
Hey Barry! (Kind of a side issue, but) Hmmm, yes, I ran out of vocabulary here for this discussion . "Capture" 720p isn't right, but "records" 1080p isn't quite right either... for the post here this seemed cleanest, but how does one say this precisely? Anything less unwieldy than "captures 1080p60 and (down/cross)converts so as to record either 1080p (over a 60i stream), 1080i, 720p, 480p (over a 60i stream), or 480i"

Or, rather, what's the verb for what the cam does with 480p? (squeeze). It doesn't capture or record it.

As a further aside - does the camera scan/capture 1080p for 4:3 and letterbox SD? It certainly doesn't use much of the sensor area... does it process the full 1080p and crop it, or just scan some of the image?

Anyway, these are not important issues, just nitpicking and trying to find a way to clarify these discussions!
 
Hmmm... scanning Panasonic materials, I guess "scans at 1080p and supports DV (480i and 480p), DVCPro (480i and 480p), DVCPro50 (480i and 480p), and DVCProHD (720p, 1080i, and 1080p) video formats and codecs" blech! The Panny materials seem a bit unwieldy, and they don't tend to use any sentences with 1080p! Perhaps this is part of the confusion here... if I didn't know off the bat that, say, the HPX shot 1080p (and how), I don't know that, say, the HPX500 website would clearly let me know that it did!
 
Captures may be the wrong word, but I think it works. Scans at 1080p is accurate.

4:3 is a center extraction. All processing is done on the 16:9 1920x1080 frame internally, and then a downconvert to the appropriate recording codec is done. For 4:3 that means a center extraction followed by a downconvert.
 
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