1080p 25 vs 720 p25 - PAL

gunleik

gunleik

Well-known member
Hi

Just curious, but to me it seems that the difference is huge.

I've been used to shoot 1080 because of the FCP issue, and was happy to do some soots in 720 after the 5.1.2 upgrade, but I think I'll stick to 1080.

And I'm a bit surprised, because I thought 720 was going to be "sort of" the same, given the cameras CCD.

Is this a specific PAL issue, as we have 1440 (europe) vs 1280 (US) horizontal lines over here?

I'm also having a hard time to monitor the 720 footage through Decklink HD pro.

Best solution so far is to upscale to 1080... -;)

After a couple of days of working with this, I think I''ve ditched the (EBU) recording format.

Am I just seeing weird stuff here, or are anyone else seeing this?

Gunleik
 
gunleik said:
Hi Just curious, but to me it seems that the difference is huge.Gunleik
Click to expand...

I agree. Although I haven't used the non Pal version so maybe it is more pronounced in the Pal version. I think that because it was easier to capture into FCP in 1080 (which is what I have been doing) you start to get use to it looks. When I tried 720 for the first time, the difference was instantly noticeable. Still, having said that, it all looks good IMO.

Thanks.
 
gunleik said:
Am I just seeing weird stuff here, or are anyone else seeing this?
Gunleik
Click to expand...

Can you be a little more specific, I mean weird stuff is what you see on the X-files isn't it ?
cheers-
 
Most of us havn't experienced this in the US. 1080p will give you a bit more resolution but not a huge amount more than 720p uprezzed (10-20%). Out of curiosity what are you basing your assesment on?

I guess it could be the more PAL scanlines since the HVX200 is theoretically capible of 1440 resolution with the pixel shift.
 
I'll post some grabs

From what I see, the diifference is quite (and surprisingly) radical. So much so that I do not think I'll shoot much 720 'cept from slo-mo.

But hey, It's twice as much data pr frame, never hurts at the same codec.


Gunleik
 
Kinda busy today, will have to wait 'till tomorrow, but it's just a simple a/b

Gunleik
 
I know.

It's soon early here, and I'm working on a gig that came thrusting in the door yesterday.

But I'll get there!

Gunleik
 
Ok, I have made a small test.

720p25 VS. 1080p25

6 frames of 720, followed by 6 frames 1080.

Both clips were upscaled to 1920x1080 in FCP 5.1.2 with Best scaling and high precision rendering. Target codec is Photo Jpeg 100%, then exported in source codec and zipped.

Both codecs has been chroma resampled using custom interpolation.

Generally the resolution is very very close, but 1080p compression is much nicer. 720's got a lot of Musquito noise, look at the black text in the top-middle.

Link 22 MB file
http://p2genie.dfmc.dk/CodecTest2.mov.zip
 
Its a nice test , but I find it hard to see the difference on this magazine. Frame to frame you see changes in the hair from the left guy in both resolutions. But realy... it is hard to see any difference at all. Thanks for trying.
 
^
Ditto. They look virtually identical to me. I've seen some shots that show some more rez in 1080p but I can't tell these apart.
 
Their is definitely more noise on the 720p footage but it looks like scaling noise not an actual increase in picture noise.
To me the 720p footage seems to stand up very well upscaled to 1080 thanks for doing the test.
 
No it's not scaling noise, at least not in the post process.
FCP 5 uses a very high quality scaling algorithm when set to "best"
The mosquito noise you see on the small black type over the yellow shirt is definitely DCT noise from the DVCPRO HD compression.
The good thing about 1080p25 is that the whole 100mbps is used for the 25 frames. thats 4Mb per frame. In 720p25 we only got 1.6mb per frame.
 
Thanks! Nice!

Tomorrow I'll do a short test a/b'ing red and strong colored subjects (that's where I first noticed) shooting first a couple of frames i 720, then a couple in 1080. Same light, same subject, same camera, same position.

Curious whether that's going to confirm or not my gut feel more than what has already been seen....

But I think the general point of 4Mb vs 1,6 Mb should give a pointer...

Gunleik
(who's been working to much on other stuff lately)
 
Anders Holck said:
The good thing about 1080p25 is that the whole 100mbps is used for the 25 frames. thats 4Mb per frame. In 720p25 we only got 1.6mb per frame.
Click to expand...
Indeed very interesting Anders !
Certainly food for thought as I thought 720p had the same compresion as 1080 and only dvcpro50 to be lighter.
 
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