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-   -   V1 problems with 1080i 25p in vegas. Help!! (https://www.dvinfo.net/forum/sony-hvr-v1-hdr-fx7/128550-v1-problems-1080i-25p-vegas-help.html)

Glen Maw August 22nd, 2008 11:45 PM

V1 problems with 1080i 25p in vegas. Help!!
 
Hi, first of all this is my first post, but I've been
reading members' threads for the last 18 months and
I'd like to thank those who've helped me out in the past.

I recently shot a short film on my Sony HVR-V1P(New Zealand)
camera. NZ is a PAL country so the camera 1080i not 720p.
I recorded to HDV (on tape) and shot it in the 25p mode.

I am editing in Vegas 7.0e and have printed to HDV tape. My
project properties are set for best, video quality is set to
high on the slider(31), The template is set at HDV 1080-50i, progressive,
and the field order is set to progressive. All individual
clips on the timeline are set to progressive in 'properties'.

I have printed it to HDV tape and run it through a HDTV and
it looked ok, but here is my problem...

I took the HDV tape to Park Road Post, Peter Jackson's
post-production facilities, to get some advice about colour
correction (they are very supportive of young filmmakers), and
we watched it on a big screen through a progressive projector,
but there were problems with field order. It was watchable
but at times it looked almost like two images were overlapping.
They thought I might have not ticked a box somewhere in the
rendering process, but as they work on the full AVID suites and not
Vegas they couldn't offer any concrete suggestions.

I don't really know what is going on, but I am starting to suspect
that the issue is that 1080i cameras with progressive scan aren't
really delivering 1080p and I only have a dv 25p quality project.

If this is the case I must have an interlaced film with a progressive
look, rather than a true progressive film. True?

Any help would be very appreciated

Glen Maw
Wellington, New Zealand
HVR-V1P, Tascam HD-P2, XP SP2 Duo-core 2.66GB intel, 4GB RAM, Vegas 7.0e

Andy Wilkinson August 23rd, 2008 01:32 AM

OK let me start then the real Vegas experts can wade in. First of all welcome!!!! I use Vegas 7e and have done a lot of work with a mates V1 (but alas only with it in 1080i mode, never tried anything else - I've always ended up dealing with the interlace issues in post until a recent self purchase of a true progressive cam).

Two things come immediately to (my) mind. Hope they help and not confuse!

When you set the project properties and clip properties to Progressive (i.e. field order 'None') did you do this right at the beginning or after you had done some/most/all of the editing. Also, did you Blend or Interpolate the fields (check boxes again). It might help to know and I believe it can be important to do this right from the outset, not just when you start thinking about rendering the finished project with all it's pan and crops etc. (in Vegas - don't do it in DVDA - but I guess you know that!)

Second, I learn't some time ago (via this Forum and Ed Troxel) that when you crop say an individual clip, it is possible for the top line to end up being switched from odd to even (or whichever way round it is) and this can sometimes cause field order problems. Very slightly adjusting the offending clips crops (literally by one pixel line) can cure this issue - this is not an issue with Vegas but an interlace issue.

OK, anyone else got any suggestions?

Glen Maw August 23rd, 2008 07:36 PM

Re: V1 problems with 1080i 25p in vegas.
 
Hi Andy, cheers for your help. The film was shot and imported into Vegas six months ago, so I can't be absolutely certain I set all of the individual clips as progressive from the outset, but if memory serves me correctly, I'm pretty sure I did. I definitely set the project properties to progressive (field order none). That is the first thing I do when I open a new project.

My properties are:
Template: Custom (1440x1080, 25.000fps)
Width: 1440
Field Order: None (progressive scan)
Height: 1,080
Pixel Aspect Ratio: 1.3333 (HDV 1080)
Frame Rate: 25.000 (PAL)
Full-Resolution rendering quality: Best
Motion Blur type: Gaussian
Deinterlace Method: None

As you can see, I have set deinterlace to none. Should I have had this set to blend or interpolate instead? I somewhat naively thought what was coming out of the camera
was true progressive. But I am beginning to realise that it isn't at all, it's just a new form
of interlacing.

I have cropped boom out of a couple of shots. Do you suggest I try to alter these by one line? I thought that because every clip is 1440x1080 I would be fine.

Another thing I have noticed - and I think this might be a clue - is this:

On the bottom left corner of the video preview screen the project and preview properties are stated. In my case:
Project: 1440x1080x32, 25.000p
Preview: 1440x1080x32, 25.000p

when I render a loop region as an m2t file these properties stay as they are, but when I go through the HDV print to tape process and the and render from the timeline, the properties on the preview change to

Project: 1440x1080x32, 25.000i
Preview: 1440x1080x32, 25.000i

but only for as long as it's rendering then they change back to progressive.

?????

Jon Shohet August 24th, 2008 04:58 AM

not a vegas user, but about the v1's progressive mode : the camera does indeed use true progressive scanning, however, since hdv spec do not support 25P it records the video as interlaced, so you end up with an interlaced signal comprised from a true progressive scan.
Likewise, when you print back to tape, you can only send to the camera an interlaced signal.
Maybe the problems occur from vegas trying to send a progressive signal to the camera and messing up the conversion?
Maybe you should first export a progressive master to file, and then import that file to a new 50i project and print to tape?
Just a thought. again - not a vegas user, but I always export my edits and composites as QT or uncompressed AVI progressive file masters before re-encoding for web\dvd. If you only plan on printing to tape i'd just edit in 50i all the way in the first place.

cheers.

Glen Maw August 24th, 2008 05:05 PM

Re: V1 problems with 1080i 25p in vegas. Help!!
 
Thanks for your suggestion. If I render my current 'progressive' project to an m2t, then opened a new 50i project and render a second time to print to tape, will I lose a lot of quality because it will have been rendered twice or because it is all in m2t will I be ok?

Seth Bloombaum August 24th, 2008 06:17 PM

Don't use M2T as an intermediate render - you're right to be concerned about that. It's too highly compressed, use as little as possible in any workflow.

A good substitute would be to do an intermediate to the AVI-Cineform codec that comes with Vegas 7. Compressed enough to be useful, but "visually lossless".

Glen Maw August 26th, 2008 01:27 AM

Thanks I'll give it a go. Another thing I've noticed is that Vegas seems to be crushing
the blacks and clipping the whites when it renders to m2t. I'm correcting between
16-235 IRE. I tried the microsoft codec check box in the 'preferences' but that seemed
to boost the contrast as well.

Seth Bloombaum August 26th, 2008 09:44 AM

Quote:

Originally Posted by Glen Maw (Post 924932)
Thanks I'll give it a go. Another thing I've noticed is that Vegas seems to be crushing
the blacks and clipping the whites when it renders to m2t. I'm correcting between
16-235 IRE. I tried the microsoft codec check box in the 'preferences' but that seemed
to boost the contrast as well.

Glen, if you haven't found it yet, there is a dedicated Vegas forum here on DVInfo - as your thread here is getting more deeply into Vegas you should probably ask over there...

Glen Maw August 26th, 2008 01:50 PM

Thanks Seth, will do. So just to clarify: HDV tape is always interlaced. Even though I have set the camera to progressive scan, what I have on the tape is interlaced. I should treat all of my projects as interlaced if I'm going to print back to tape. I can't send progressive renders back to the V1 - it will turn them into interlaced signals and therefore Blu-ray or some other HD print is probably the way to go if I want a progressive product.

I.e, I should think about my delivery formats early on.

Jon Shohet August 27th, 2008 01:33 AM

Moving this thread to the vegas forum is a good idea. You can only print to tape 50i, but there IS a chance that Vegas DOES know how to print 50i correctly on the fly from a 25P project, and that your problems lie elsewhere.

That said, REGARDLESS of camera model or NLE, making an uncompressed/lossless codec digital file master is always good practice. When printing to tape you are re-encoding your final edit back to m2t, which is a lossy delivery format, and it is not a replacement for a true master.

Leslie Wand August 27th, 2008 01:54 AM

Quote:

Originally Posted by Jon Shohet (Post 925455)
That said, REGARDLESS of camera model or NLE, making an uncompressed/lossless codec digital file master is always good practice. When printing to tape you are re-encoding your final edit back to m2t, which is a lossy delivery format, and it is not a replacement for a true master.

not if you're using smart render.

leslie

Jon Shohet August 27th, 2008 07:08 AM

Doesn't smart render mean that Vegas re-encodes only what it has to?
What about the parts of a project with effects, transitions, multiple layers and overlaid titles?

In any case my point was that if your only method of archiving is to tape, be aware that you are left with a master which is in a heavily compressed format, and one that you have to recapture from tape should you ever need it again.

Seth Bloombaum August 27th, 2008 09:00 AM

Smart render is as Jon describes.

Smart render for Vegas was introduced in V8 Pro - the original poster is running V7.

Leslie Wand August 27th, 2008 05:17 PM

Quote:

Originally Posted by Seth Bloombaum (Post 925601)
Smart render is as Jon describes.
Smart render for Vegas was introduced in V8 Pro - the original poster is running V7.

sorry, didn't realise he was on 7. as for dissolves, etc., i'm quite aware of the re-encoding....

my normal work flow for the majority of my clients is a quick (raw, no effects, titles, etc.,) rough cut (which after approval i then back-up to tape), after this we then put in bells and whistles, sound mixes, etc., (keeping veg so if re-edit is necessary it's very easy loading tape and veg...)

this works well for doco, don't know about any other format though.

in the early days of hdv we were simply doing what we did with sd, and to be perfectly frank, i think there's an awful lot of bull written about generation loss unless your doing compositing / green screen stuff....

leslie

Glen Maw August 28th, 2008 07:19 AM

thanks for your input guys


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