Frame Rate Mystery

[Graham Jones]

I have posted this elsewhere in the forum, but guess this is the best place for it.

I am using the JVC GR-PD1 to shoot a low budget feature which will finish on 35mm. I selected the PD1 over the HD1/HD10 because of frame rate. I explored frame rate conversion programmes to convert the HD cams 30p to 24p but didn't feel confident from the tests I saw that I would be protected...

The PD1 shoots a nice image in true 16:9 at 25p.

I just have one query. The component Y/Pb/Pr output has two settings, both of which are 50 frames per sec. To quote the manual

'576/50P: signals are output in progressive scan mode (FACTORY PRESET)'

576/50i: signals are output in interlace mode.'

That's it.. no 25p output.

I haven't made a mistake and shot at 50p - which is indeed possible - I am definitely shooting at 25p, but irrespective it outputs at 50p/50i depending on how I set it. There's no other option.

It's even articulated by the manual which says that HI-RES mode:

'records signals in the progressive scan mode (625 scanning lines at 1/25th of a second for recording and 1/50th of a second for playback at one time).'

I have experienced some MPEG2 NLEs getting confused by this and playing footage too fast and saying it's 50p... though not the bundled NLE MPES PRO - it knows that it's really 25p.

I assume that 50p playback doesn't truly affect frame rate - that the frame rate is still 25p: as there are only 25 differences a second?

However, I am transferring to 35mm, where 25p will be vital, and I just wondered if anyone had any idea whether the fact that technically it's coming in at 50p will matter.

I'm doing a test in less than a month, so will find out... but I just wondered whether anybody had anything to say in advance.


G

[Graham Jones]

I should also clarify: I don't have any editing difficulty. I am using the bundles MPES PRO and find it very satisfactory. I am exporting the results back to Mini DV at virtually 100% quality.

It's just that when I transfer them from cam via the said component output, it will technically be 50p, even though my work is a very deliberate 25p.

[Maury McEvoy]

<<<-- Originally posted by Graham Jones Senior :

That's it.. no 25p output.

I haven't made a mistake and shot at 50p - which is indeed possible - I am definitely shooting at 25p, but irrespective it outputs at 50p/50i depending on how I set it. There's no other option. -->>>

My guess is that every 25p 'camera' frame is output twice (i.e. 50p).

You may need to convert your output from 50p to 25p (i.e. remove every other frame).

My GR-HD1 duplicates output frames if the shutter is set to 1/15.

[Daniel Moloko]

i think you lost the chance to shot with the HD10u, cause for sure you can transfer to 24p with good results:

http://www.dvinfo.net/conf/showthread.php?s=&threadid=27888


you can even use the TWIXTOR PRO to archive some good motion

ciao

[Graham Jones]

I clicked on that link, Daniel, but found no sample clips of HD10u 29.97 -- 24 conversion?

Just a debate about it and some other things. I have viewed such samples elsewhere and been unhappy.

You talk a lot about shooting your first feature on Super 16mm rather than HD. Well, I shot my first feature on Super 16mm and blew up to 35mm and am shooting this, my second on PD1 and transfering to 35mm.

Each project has it's own requirements. It's never just technical. There are always production considerations which have a huge effect.

What I mean is: I would shoot o Super 16mm or HD if that was appropriate... it's not, Pal 25p is.



I'll see how the test comes out - but I think I probably do have 25p.

[Daniel Moloko]

theres a sample made by LES DIT if you look at the replies.

it is great!

tell me what samples have you seen? i want to check it out.

have you seen any sample at the theatre?

ciao

[Graham Jones]

Yeah, that's the clip I've already seen. Sorry, I didn't notice there was more than one page!

Daniel, it's terrible. The frame rate conversion has fuzzed it. Transfer that very clip to 35mm and I think you will be unhappy.

I could be wrong.

Les himself says:

'Tell me your opinion of the artifacts from converting 30fps to 24. In motion, like a real audience would see it. Not paused, movies don't pause. I'm curious what you think. Please don't comment on the crappy hand held camera work, I was just testing the camera out !'

I appreciate all of this... my opinion is that it's quite poor. You can feel the power of HD but it's discounted and fuzzed and transfering that to 35mm? Nah.

Again, I could be wrong.

If I found a way to go from HD10u - 35mm I would switch to HD10 immediately. I tried for months and couldn't. The frame rate is too big an issue for the folks who do the 35mm transfers... and my eye can see why.

[Daniel Moloko]

Maybe i dont know nothing about anything.

cause i think the footage looks good. i think its better to have a 35mm footage that looks like that one, cause i just cant stand DV transfered to 35mm. looks like junk.

so, if i have to choose from two kind of junk, id prefered the junk from HDV. that's my guess.

ciao

[Graham Jones]

nobody's talking about transfering DV

[Graham Jones]

Best of luck - just make sure to test the process in it's entirety (HD10u - Frame Conversion - 35mm) before prinicipal photography begins!

[Daniel Moloko]

yeah
im not talking about DV transfer.
im just talking about in what format i can film. and i cant afford to film in another high-end format. im talking about 3k cameras.

so, if im working in that budget, i only have two choices, one is DV and the other is HDV.

HDV has the "problem" of frame convertion.

DV is the problem itself - very bad image.

i prefer to get the look of HDV in the post.

what about you if you had to choose between DV and HDV?

ciao

thanks!

[Graham Jones]

'what about you if you had to choose between DV and HDV?'


Well, 28 Days Later was shot on DV. It's a good example of what can be achieved - and a reminder that it's not only about camera resolution, but also lights and post production processing.

The PD1 I'm using has a DV mode, like the HD1 and HD10 but I don't use it

I use HI-RES mode, which is a lower resolution version of HI-DEF mode on the HD1 and HD10 but with 25p not 29.97p.

[Graham Jones]

Every project is different - but testing is vital.

Testing your proposed process always throwns up unexpected surprises.

That's why I'm testing PD1 to 35mm, to see if the 50p output matters. I don't think it matters - as it's still 25p - but I will only know when I see them do it. When I look at the cinema screen and see my footage playing.

You have to do that too, otherwise you might be very surprised down the line!

[Daniel Moloko]

i think 28 days later looked terrible, on the cinema screen.

my project dont support that kind of bad tasting image provide by DV, i mean, ANY DV. im seen a lot of dv footage tranfered to 35mm, nothing was good at all. it is a resolution problem, for sure.
(not even robert rodriguez like the DV format printed on 35mm)

but yes, you are right i got to see by myself the printed 35mm version of HDV 30p footage.

but i do believe in LES DIT. who said its good for most audiences.

anyway, have you seen any HD10U footage printed to 35mm at a cinema?

ciao

[Graham Jones]

so you think 28 days later looked terrible on the cinema screen, but that skateboarding footage will look good?

beauty's certainly in the eye of the beholder.

if we all saw the same thing - films would be boring.

best of luck