60i to 24p
 

Hello. Does anyone know if you can take 60i footage and effectively turn it into 24p footage, or something almost equivalent? It is my understanding that the best picture quality to be had with this cam is that of 60i. I guess you can use an app in post to make it close to 24p. Basically, I want the best possible picture quality and the most "film-like" look achievable from the xa-a1, if I buy one. One day I will cease being a newbie and join the ranks of the tech-savy, but that process would be greatly slowed were it not for the knowledge of the members of dvi; thanks in advance guys.

I would think you would want to shoot it in the 24F mode if that is your desired output, and not 60i and have to deal with deinterlacing, pulldown, etc. in post. I am not sure you would ever yield better results creating your 24p in post than just shooting 24p(F) to begin with.

Enlighten me if I am wrong, though.

Many options for 60i to 24 p conversion
 

If you use cineform products the HDlink will perform this.

Red Giant Magic Bullet Suite 2.1 will do a great job with After Effects.

And the latest and I will say the greatest is the Red Giant Frames product.
This will work with many applications including Avid, Premiere, Final Cut, and of course afer effects.


This is almost ready to be released and I am using it in beta.

http://www.redgiantsoftware.com/magicbulletframes.html


Also After Effects alone will perform the conversion.

Go here.
http://www.videocopilot.net/tutorials.html?id=41
Darrell

I would just shoot in 24f...but it degrades resolution.

Not really. The rez with the A1 is so high to begin with, the small vertical rez loss shooting in 24f is negligible.

Bill

Then, by that logic, would it be smarter to shoot 24f over 60i, seeing as deinterlacing causes picture degradation as well? Does deinterlaced 60i footage suffer a greater resolution loss than canon's 24f mode?

The difference is negligible. If you want to end up with 24fps, it's better to shoot it that way from the beginning. You don't have any interlace artifacts when you export for DVD, fo rone thing. Secondly, since it's a real 24 frames that go by in a second, the motion is different from 60i converted via reverse pulldown. I don't see that "judder" when shooting at 24 fps.

Interesting. If one were to use a percentage scale for how much resolution is lost by using the 24f mode over the 60i mode...what would it be? 10 percent?

The 24F on the XH-A1 is simply stunning in my opinion. I just got the camera last week. I know that resolution is supposed to take a 10% hit in 24F and 30F, but I can't see a difference. It looks better to me than the "true" 24p from my HV20. I am a certified pixel peeper, and from my standpoint I think that the skepticism about 24F is a bit over the top. The other advantage of 24F, as opposed to 24P coded with pulldown on M2t is that only the 24F frames are encoded so you have more bandwidth to handle both motion and detail. At least as I understand it, you are less likley to get motion artifacts from 24F. You need to use editing and capture software that can handle 24F. In my case, I am using Cineform's Neo HDV to capture and Vegas to edit. My jaw dropped when I saw my first 24F footage captured and processed to 1080 24p. 24F files are also processed more quickly than 60i (or so it seems).

I can't see any reason to not use 24F. I think you will lose more resolution and waste a nice feature if you start with 60i.

Pat

Pat,

As I am new to all of this, I wasn't aware that you could convert 24f to 24p. How is this done? Does it degrade the image resolution in any way?

Hi Spencer, 24F is 24P. It is captured with a non-progressive sensor but converted to true progressive frames in-camera, then true 24P files area written to tape as HDV, without pulldown. Your capture and editing software need to be able to figure out that it is 24P on the HDV file, not 60i. There's tons of posts on this. Here's one I found with a forum search for "24F" :

http://www.dvinfo.net/conf/showthrea...&highlight=24F

Even though I can't see it, there is apparently a real loss of resolution to the tune of 10% to 12%:

http://www.dvinfo.net/conf/showpost....0&postcount=39

If you use 24F from the camera you will be on the fast track to great looking, true 24P footage at the end of your editing process. If you convert 60i to 24p, you will spend more of your time and the computer's time doing so. I would hazard a guess the net reolution would not be any better than 24F (which is Canon's flavor of 24P)

Pat

Thanks for the info, Pat. Most helpful.

Here is the link to the thread from about a year ago where I posted resolution results for the Canon XH-A1 and HV10 acquired with the Imatest MTF50 image testing software. The links to the data charts are dead, but the posted results are still shown and they are valid.

The bottom line is that 24F and 30F do show a resolution loss of 10-12% compared to 60i, in the vertical direction only, no loss of resolution in the horizontal direction. So the overall resolution loss for the picture taken as a whole (veritcal and horizontal) seems rather small numericaly, but you should be the judge of that.

http://dvinfo.net/conf/showpost.php?...0&postcount=39

Edit: Pat Reddy already found the post! Good job Pat!

I think it was the other way around. You got more motion artifacts from 24F than in 60i. It shows especially if you do some panning shots.

I think he's referring to MPEG-2 encoding artifacts. Less pictures to encode per second = less stress on the codec.

Keep in mind that resolution loss is not the only factor in the resulting image...as has been mentioned before. When the software converts from 60i, it has to guess the extra lines using complex mathematical algorithms that can guess wrong. You'll get goofy edge stuff in motion areas with limited contrast. This doesn't happen when capturing in frame/progressive mode...you just get that timeslice written to tape with whatever amount of natural motion blur happens within that timeslice.

I agree with Taky, during a shoot with 24F I experienced the jaggies and was really disappointed. Any other time 24F is very impressive. If its a planned shoot and panning is considered... use 60i just like you would if you were planning a slow motion shot.

Chad

If you shoot in 24F you should have fewer compression artifacts in panning and high-motion scenes than with 60i in the same circumstances. With 24F the codec has more "headroom". But you will have to watch out for the standard high motion issues associated with any 24P filming. If panning is too fast, the video will be choppy. If the shutter speed is too high you will see a strobing effect. Shutter speeds of 48 are commonly used. You can increase or decrease this to achieve the look you want or to accomodate exposure issues. You can also pan as fast or as slow as you want if it serves the look you are going for and you are happy with the results.

Pat

Use 60i. Convert it to 24fps only if you want to print to film. 60i is simply better (smoother) than 24p. 24p judder is a shortcoming of film, not a feature!

Well that's highly subjective, isn't it? :)

I much prefer my videos from my XHA1 in 24F mode over 60i. I'm not a fan of the standard ultra smooth 60i video look at all. My first DV camcorder was the original Canon Elura which I bought specifically because of its 30P mode. It wasn't quite 24P but it did offer a nice filmic alternative over 60i.

To each their own of course!

I don't like interlaced at all. The combing during motion drives me nuts and forces me to deinterlace every single piece of footage I shoot, my solution is to shoot in Frame mode to lose my 30% rather than the 50% of deinterlacing. Plus I get the nice averaged motion of a shorter timeslice that looks more cinematic than the right now video feel of 60i.

These are all personal opinions (I think lots of folks here share them), but 60i is great for doing slo mo work and for getting that news-cast immediacy that the public has been assimilated to...in much the same way that they have been assimilated to seeing progressive footage with its associated juddery (assuming you're panning too quickly or not quickly enough in the case of following motion on screen).

Speaking of which, does anyone know if the ASC's panning speed charts are posted online anywhere?

I am going to hijack this thread, if I may, because it is on topic. What is the best way to deinterlace 60i footage to get to 24? I have some footage, mostly 24F that I am cutting in a 24F sequence but need to use some 60i footage as well. Is there a better way than just dropping the 60i into my 24F sequence in FCP?

Thanks