View Full Version : shoot progressive or deinterlace in post?


Ali Jafri
September 3rd, 2008, 12:38 AM
Hi people, just a quick question: If I'm aiming for a DV PAL master, which of these two methods would give the best (and most filmic) quality?

1. shooting in progressive mode and staying in this format

or

2. shooting in interlace, editing and colour correcting, and THEN deinterlacing in post before printing out a master to DV PAL.

My concerns are motion judder in fast camera swishes and pans and in scenes that involve fast moving objects such as passing traffic, etc.

Steven Bills
September 10th, 2008, 06:20 PM
Since nobody has responded to this thread, Ill give it a shot.

I'd do tests. Set up the differing situations that you'll encounter, and then shoot them both interlaced and progressive, and go all the way with them (color correcting, etc...), and see which one you like best.

That's what I'd do.

SB

Daniel Alexander
September 10th, 2008, 06:54 PM
what is it exactly you aim to be filming?

Aric Mannion
September 11th, 2008, 12:44 PM
Progressive is better than interlaced, but I think you are talking about 24p rather than 30p? You will get juddery pans in 24p, so you may want to shoot interlaced. But 30p is best whenever possible!!

Mike Gunter
September 19th, 2008, 08:13 AM
Hi,

The original poster is in PAL-land, so 25P would make more sense. If there would be a film transfer later, dropping a frame per second would be possible, too.

For NTSC-ers, the question's dicier. If one is keen on the cadence of 24P, then shooting in 24P is how you really need to do it, although 30P will be smoother, and 60i smoother still.

But that, of course, is the point. Getting some motion blur from the process is what you're after.

Mike

Cole McDonald
September 19th, 2008, 08:03 PM
what do you intend to do with the footage when done? Are you playing it from DVD or do you intend to do a film print of the end product?

If DVD, I would shoot progressive... no de interlacing is going to get a "real" progressive look and feel to it. It's simply missing the extra timeslice that makes the motion blur natural.

The panning judder is due to pans that are faster than the frame rate will handle and is a problem in film as well. The ASC manual has acceptable panning rate charts to prevent specifically this. Pan more slowly or more quickly to avoid the "judder" that occurs in the middle speeds.

I'm not entirely convinced that 24 fps (over 30 frames or even 25 frames) is as necessary to get the "film feel" as just shooting progressive. I've posted quite a bit on this here, to wit: I've seen 60i video that looks and feels like film and 35mm film that looks like video. Camera motion does alot, spending time on everything other than the camera does quite a bit to get the "cinema feel" as well.

Good actors and can't be discounted either as they perform movement in front of the lens that gets translated into motion in the camera.

Well recorded and produced sound plays a huge role as well in giving the picture a sonic life that transcends the picture entirely and makes it "feel" more cinematic.

A well pre-produced color palette in set, costume and makeup lit really well also gives the "film feel" which is still nothing inside the camera. The "Film Look" that everyone is searching for inside the camera exists outside the camera and has to do with the art and craft of filmmaking, not the technology... even the editing plays a huge role in determining whether or not your footage will be accepted as "cinema" which is more than just "film".

Christopher Ruffell
September 25th, 2008, 02:24 PM
I always, always shoot progressive on my own projects, and where I shoot on others, I shoot progressive if it makes sense (i.e. the other B-Roll and other cameras are shooting progressive as well).

My only progressive option is 24P, and like others have shown in this thread, if done right, it works out just fine.. smooth pans, smooth camera.. smoothness is general is a must anyway, right? ;)

I feel progressive doubles your resolution and 'feels' more professional when watched - I'm a die-hard progressive guy. Deinterlacing 60i footage never works out as nicely as one would hope - halves the resolution (even with smart deinterlacers).

Alex Humphrey
October 13th, 2008, 06:12 PM
Ali,

I'm guessing 25p for you. I shoot 24p here in the United States for everything including soccer (Futbol/football in the rest of the world) Only a narrow panning speed looks juddery, and to be honest, pan with a subject moving and everyone forgets about it anyway.

Here in NTSC land 24p played on a DVD player on a HDTV looks better than a 30p or 60i signal on the same DVD player and HDTV. So assuming that PAL is similar in your area, I would stick with 25p and avoid 30p. But test and pay attention to the final result, especially with static cameras on various manmade objects (straight lines) and see if there the annoying flexing/interlaced/oversharpening lines happening. IF so, drop the edge enchancement and verify that you shot in 24/25p and encoded your DVD in 24/25p. Then check your panning speeds. I think you will settle on progressive scan in the end. But then again I hate interlaced images.

alex

James Martin
October 21st, 2008, 01:43 PM
To be honest, this shouldn't be much of a question at all....

1) if you know whether you really want progressive (going for a film look?)

2) your camera can shoot genuine progressive..

If it is yes to BOTH of those answers, then yes - shoot progressive!

If no to either, shoot interlace and de-interlace in post (put a lot of time aside for this) for the best quality - hardware de-interlacing on cameras can often be flawed.

What is the camera?

Also, regarding motion judder - it will be just as bad if you shoot progressive as if you de-interlace - the de-interlaced version will simply be blurrier (and undesirable effect).

Michael Kraus
October 21st, 2008, 02:43 PM
I feel progressive doubles your resolution and 'feels' more professional when watched - I'm a die-hard progressive guy. Deinterlacing 60i footage never works out as nicely as one would hope - halves the resolution (even with smart deinterlacers).

Does shooting progressive truly double resolution or was that just to say that it looks as though it has a much better resolution?

Also, does de-interlacing actually cut the resolution in HALF? Seems a bit more believable....also seems like de-interlacing would be blatantly and utterly obvious....possibly not ever worth doing....

I just de-interlaced a recent SD project and I don't think it quite cut the resolution in half....although there is certainly a bit of a difference.

Ben Winter
October 28th, 2008, 02:54 PM
Hi,

I shoot everything in 60i and convert to 24p later. This may be because I have an FX-1 and it's all I can do, besides using the unsightly Cineframe modes which I avoid except when in a rush.

But 60i -> 24p in post has a lot of advantages. One, it does not halve resolution. The very mechanics of interlacing prevent this. If the frame is completely still, you have full resolution. If the frame is still and something is moving in the frame, that moving object is reduced in resolution depending on how fast it is moving and even then the "fraction of deresolution" is subjective. The only way for deinterlaced video to be completely technically "halved" in resolution is if the camera is moving fast enough to cause the even and odd frames to decouple completely from each other and visually become disassociated.

Two, deinterlacing in this manner gets rid of the sharp "video" look. There is a quality to it that provides a more filmic presentation. But if we're in the business of quantifying things here I'd say the film look has about 40% to do with the frame rate of the video. The other 60% is lighting, camera movement, coloring, etc. The film on my website "One Headlight" has received a lot of questions about what film stock it was shot on, and it was shot 30p on a GL2!

A good example of 60i to 24p shooting is "The Lifeguard" on my website, as it demonstrates a variety of shooting situations; there is a link to an HD version if you are interested.

Three, you have the option of achieving lossless slow motion effects by separating the even and odd fields and deinterlacing them individually, giving you twice as many frames. By lossless, I mean you are not relying on a program to completely generate new frames from existing ones, something called interpolation. Granted, this is *technically* a complete 50% resolution loss but visually not so. It's much like compressing an audio file to mp3 format; technically, you're losing a majority of the information, but most of it is nonessential. I hope that comparison makes sense.

I would suggest shooting progressive if none or few of the advantages above apply to you.

Ali Jafri
October 29th, 2008, 10:08 PM
I hear you Ben. I too have been experimenting with deinterlacing techniques in different areas of the workflow chain. I too have an fx1. I love the deinterlaced look as opposed to straight interlaced video fields but sometimes the picture gets way to soft and looses detail. I've used the cineframe option on the camera but i get too much judder. I shoot in dv pal since that's what i master in. I'm interested to know how you get your deinterlacing done. Do you use your NLE or any other third party plug-in? When do you deinterace? Before applying any color correction or once all post is done? I think it'll all make a difference in the final result. I'm using both premiere and vegas to edit my work and both have very different ways to deinterlace. Of course, this question is open to everyone and i'd love all the help i can get :)

Ben Winter
November 1st, 2008, 09:29 AM
I use DVFilm Maker to deinterlace from 60i to 24p. I think it's the best/smartest deinterlacer for that purpose available, at this cost anyway. I'm curious how much detail you're losing with your deinterlacer; with Maker, I'm losing virtually none. See the attached pictures; completely uncompressed, straight-from-Ppro framegrabs. I suppose the proof is really in the more motion-crazy shots however.

The best workflow for me in terms of quality is to convert 60i -> 24p with Maker, then edit in a 24p timeline.

I don't do much color correction but when I do it's one of the last things, after deinterlacing definitely.

Gary Nattrass
November 4th, 2008, 11:39 AM
I shoot HDV 1080i 50i and then master to pro res 422 1080i 25p

Alex Humphrey
November 8th, 2008, 12:02 PM
follow up thought from my iPod

Another reason to consider 24p over 60i is post production time (25p for pal land) is post production time. Editing 24/25p and going to DVD 24/25 is MUCH faster! My methodical testing of 24p to DVD was 2:1. 60i to 24p DVD was closer to 3:1 or 4:1 and 30p to 24p DVD with good motion conversion was closer to 8:1. 30p to generic DVD never looked very good to good. Now when most people own bluray players and we can have cheap bluray players, then 30p would be a super choi e along with 60p. But we are still a few years away from that. Movie theaters are starting to go all digital, 24p is what they are geared for, but they should be able to correctly handle all formats, so really this type of thread will be outdated in a couple years anyway.

Cameron Smeal
March 14th, 2010, 10:09 PM
Guys, sorry for opening up and old thread but it's discussing an issue I have now and I'd really appreciate some expert help and it looks like you are all on top of it.

Gary - particularly interested in your experience.

I'm in PAL land shooting 1080/25p on the HVR-Z7p. I'm editing on PP CS4. I'm facing this exact dilemma due to having to make a decision about the BMD Intensity. We are about to go into principal photography for a doco in Thailand and we would like to shoot using the Nanoflash @ 35mbps 422 to give ourselves some more quality. Now we will be coming off the HDMI and rather than ingest over HDMI using an Intensity card, we will transfer via CF card but we want to use the Intensity to monitor and playout in PP timeline, etc. We would probably also use the MainConcept HD 4 codec for this work.

Bare with me..

Problem is, BMD does not support 1080/25p. I realise that this is an old topic. Sorry. According to BMD 25p is an 'edge case' format and they advise to shoot 1080/50i. What I am really struggling to understand is that if I want to make a creative choice to shoot progressive (for the reason you all have mentioned above), why would I shoot interlaced when the entire post industry here is Australia is geared for 25p? Am I missing something?

Does this mean I have to just say sorry BMD and look to AJA or MOTU to provide the solution or have I really, really misunderstood this?

Anyone's would be greatly appreciated.

Aric Mannion
March 17th, 2010, 10:19 AM
I hear you Ben. I too have been experimenting with deinterlacing techniques in different areas of the workflow chain. I too have an fx1. I love the deinterlaced look as opposed to straight interlaced video fields but sometimes the picture gets way to soft and looses detail. I've used the cineframe option on the camera but i get too much judder. I shoot in dv pal since that's what i master in. I'm interested to know how you get your deinterlacing done. Do you use your NLE or any other third party plug-in? When do you deinterace? Before applying any color correction or once all post is done? I think it'll all make a difference in the final result. I'm using both premiere and vegas to edit my work and both have very different ways to deinterlace. Of course, this question is open to everyone and i'd love all the help i can get :)

I have an FX1 and de-interlace by interpreting footage in After Effects. I've read it's a very good method of de-interlacing, but all I know is that the fields are too disturbing for me to look at and they have got to go.
I use Final Cut to edit, so it is a pain to de-interlace in AE, unless the video is heavy with special effects. But recently I have tried changing the sequence settings in Final Cut so that feilds are set to "none" instead of "upper". That actually seems to effectively de-interlace my footage. Has anyone else tried this method?

Sareesh Sudhakaran
March 19th, 2010, 03:33 AM
de interlace later if your export is an image sequence. anything else, shoot progressive.