DV or HDV?

VirtualSki wrote on 2/17/2008, 9:05 PM
I'm brand new to Vegas. My current project is transferring 16mm to my Sony HDR-HC7. I'm playing a 16mm projector onto a screen and visually recording it to the HDV camcorder. I've been recording in DV mode because the source is 4:3. An important point to be made is I'm not "filling the screen" during the transfer process (to be certain I capture all of the image borders) because I know I can do so (fill the screen) in the editing process. But, I just now realized the DV files are larger than the HDV files for the same amount of recording time (I would also prefer to record only in HDV mode; it makes the capture to computer easier for me). So Here's the question: Am I correct to assume there's no reason not to record in HDV (there'll just be more "blank area" in the HDV screen)? The 16mm is very old film (read, resolution not that great). In the end, am I correct I can still create a final 4:3 video?

Comments

John_Cline wrote on 2/17/2008, 9:15 PM
I'm kind of surprised that this is working at all. There is a disparity between the frame rate of the 16mm film (typically 18fps or 24fps with sound) and the frame rate of video (29.97fps NTSC or 25fps PAL), so it seems that would would be seeing a significant amount of flicker.

That said, filming in HDV would give you more resolution to work with when you zoom in in post production.
jrazz wrote on 2/17/2008, 9:23 PM
John Meyer seems to have a workflow set up for transferring film to modern media (I think he even has a patent in the works for how he is doing it).

Regardless, you may want to look him up via the search function (if it is working now) and read some of his posts concerning transferring film. His user name is johnmeyer.

j razz
johnmeyer wrote on 2/17/2008, 10:11 PM
Bob (Farss) also knows lots about film transfer.

Here's a basic primer about various ways to do film to video transfer:

Transferring 8mm film to another format

The title says "8mm," but it applies exactly the same to 16mm.

The lowest quality way to transfer is to do what you are doing. However, for many situations, that may be enough. When you do the transfer this way, you need to use a flat screen. A beaded screen will make things nice and bright, but will blur the image. You also need to get the camera "on-axis" with the projector.

You might want to experiment pointing your camera directly at the projector. I actually discovered that if you have a lens on the projector designed to project onto a distant screen (i.e., telephoto, not wide-angle), that you can point the camera directly at the projector lens and eliminate the screen altogether. I use a 25 watt bulb in place of the 300 watt projection bulb. If you haven't reduced the bulb brightness, you will need to use an ND filter before you try this approach. Also, you will have to flip the image in Vegas (which is a trivial one-click operation in the pan/crop dialog) because the image will be upside down. I told Roger Evans (the inventor of the Workprinter transfer system) and he has subsequently been able to eliminate the external "aerial" lens that caused so much rainbowing and fringing if everything wasn't set up perfectly.

Back to your transfer. The two big problems with this method (pointing the video camera at an unmodified projector directly or via a screen) are: 1. Flicker due to the shutter. 2. Blur due to cross faded frames.

Sound film is 24 fps. Silent is 16 or 18 fps, although home movies can be just about anything, especially since most early home cameras were either hand-crank or spring powered. Video is 29.97 (NTSC) or 25 (PAL) fps. Your projector probably uses a three-bladed shutter which means that the shutter closes each time the film is advanced to the next frame, but also closes two more times while each frame is projected. This is done to increase the flicker rater in order to make it less noticeable and keep the audience from getting a headache. So, as you film the projector, your camera is seeing a frame of film, then complete darkness (while the shutter is closed), then either that same frame of film, or the next frame. If you draw a time diagram of what the projector is doing and what the video camera is doing, you will find that the ratio between all-black and the frame of film can vary quite a bit depending on when the video camera happens to take its frame of video compared to where the projector happens to be in its projection cycle. As a result, you will end up with flicker, since some frames will be brighter than others. One way to reduce this flicker is to find a five-bladed shutter projector, but those are tough to find, and are expensive. The reason they flicker less is that there is less difference between the lightest and darkest exposures.

There are two other things you can do to reduce flicker. First, make sure your video camera is set for 1/60 shutter speed. Do NOT use a high shutter speed. You can experiment with a lower shutter speed, but you can't go lower than 1/30.

The second thing is to vary the speed of the projector. Not all projectors are variable speed, but if your is, then fiddle with the speed while looking at the video on a monitor, and try to get a speed that gives you the lowest flicker.

Finally, if you really want to get serious about this, then you need to use a method, such as the Workprinter, or the process I developed, that will give you exactly one frame of video for each frame of film, with no shutter darkening. However, this takes a lot more work and $$$.

Hope that helps.
VirtualSki wrote on 2/17/2008, 10:15 PM
Yes, I'm having some flicker...but it's not really that noticeable...and not at all when the scene isn't bright (and content is king). My HDR-HC7 is new, too, so I'm at a disadvantage but I believe I can slow the shutter speed to match the 16mm.
John_Cline wrote on 2/18/2008, 6:22 AM
Donald Graft has written a "deflicker" filter that works in Virtual Dub. When you have to shoot film by aiming a video camera at an unmodified projector, the result is really quite amazing.

http://neuron2.net/deflick/flick.html

He has also written a "hotspot" filter which solves another problem when shooting film from a projector.

http://neuron2.net/hotspot/hotspot.html

John
RalphM wrote on 2/18/2008, 7:03 AM
John Cline,

Is this the same deflicker filter that existed about 4 years ago in virtual dub? I have used it in the past with success, but it required an older codec to run and I'm not sure I can find it anymore.

Super8 Sound is the toughest film for me to transfer. I use a modified variable speed projector and the lens/mirror arrangement from one of Moviestuff's units. Unfortunately getting a flicker-free transfer almost always results in speeded up audio. This requires extra steps to achieve good audio, either adjusting pitch or stretching the A/V. Neither approach is without issues.

A deflicker filter would probably be a better approach to sound film.

Thanks,
RalphM
John_Cline wrote on 2/18/2008, 7:24 AM
Ralph,

Yes, but it has been updated within that last four years. About the codec, it doesn't "require" a specific codec, it uses any codecs which are available to Virtual Dub. If you are processing DV footage, you must have a VFW-compatible DV codec installed on your system as the Vegas DV codec isn't available to programs outside of Vegas. Lagarith and HuffYUV are very good "uncompressed" intermediate codecs for getting footage to/from Vegas and Virtual Dub.

John
RalphM wrote on 2/18/2008, 8:19 AM
Thanks John...

RalphM
VirtualSki wrote on 2/18/2008, 11:34 AM
Now that this thread has gotten off course, and risking two more dudes with Fedoras and trenchcoats showing up at my front door, I'll end it with a thank you to all for the great info!
johnmeyer wrote on 2/18/2008, 5:56 PM
Now that this thread has gotten off course, and risking two more dudes with Fedoras and trenchcoats showing up at my front door, I'll end it with a thank you to all for the great info!

Gee, that would be me!! (well, at least this is me 34years ago ... my size 7 7/8 head didn't fit the borrowed hat ...)