iPontificateMore On The DV To 35mm Transfer Process?

by

- December 30th, 2004

I recently completed a short film as Director of Photography using the Panasonic DVX100A with the intention of blowing up the image to 35mm film for festival releases. The short film, titled Oh My God, has recently been selected for the acclaimed Sundance Film Festival 2005 taking place this January in Park City, Utah.

The festival requires that the films to be screened be delivered on either High-Definition tapes or on 35mm reels. The transfer was done by Marcus van Bavel from the outfit DVFilm.com and we followed the optimal setting suggested by the site for the Panasonic DVX100A during principal photography as covered in my last article on this topic. The 35mm print arrived earlier this week, the Director, John Bryant, and I screened the print last night after hours at the Alamo Draft House located here in Austin, Texas.


Director John Bryant holding the new 35mm Print of Oh My God

John Bryant gave some technical details of the transfer process including what was needed in the deliverables given to DVFilm.com for the transfer to film...

John Bryant: When you're finished editing your film and you have a completed version, here's what we delivered to Marcus at DVFilm.com. An external hard drive with the short film exported at 23.98 frames per second in a QuickTime file. Our film was 10 minutes long. This file size was just about 2.0 Gigabytes. The sound was mixed down to two tracks. We had a sound POP four seconds before the film started and four seconds after the last frame of the film to make sure the project stayed in sync.

Sound is a key element when making a film and often times gets neglected leading to an undesirable viewing experience. During production, we used an Audio Technica AT 4073A shotgun microphone as our key sound mic attached to the camera directly. Our second source for sound came from the on-board camera mic on the DV100A in case the levels peaked on the shotgun mic. Since there was a lot of screaming required for the scenes, there was no real way to adjust levels during filming. This set up gave us the flexibility needed to capture adequate audio levels; one mic was set hotter than the other on two different channels to capture both the low and high levels of audio and dialog.


Reel being re-threaded after viewing.

John Bryant: All the credits and still pictures that were intercut with the credits had to be recreated to HIGH RESOLUTION (1280 x 768) so that DVfilm could re-render them and they would look good -- DVfilm can duplicate some FX work on the credits (i.e. -- the credits zoom or grow in the screen).

DVfilm was able to adjust a few shots where the boom/microphone came into frame slightly ... now they're no longer there. Also, they were able to re-frame where there was tape on the edge of the frame from the glass we put in front of the lens to protect it from flying blood.

Another concern we had about the quality of the image when transferring from the original DV cut was color correction and Gamma control. There were some key elements during certain scenes that needed to be viewed clearly. While the original DV cut looked fine, some brightening needed to be done in order for correct viewing from the film transfer. Also, at the climactic end, there are large flashes of light that could create an issue with over-exposure on the 35mm print.


Actors Jason Foxworth and Jessie Schwartz

John Bryant: Color correction. There was one scene where the blood looked like grape jelly. They color corrected it so the blood looked real. Also, there was one or two shots where the exposure was too dark -- and you couldn't really see a gun that Jason Foxworth was picking up -- and you couldn't see too much detail in his face. They are tweaking that as well.

John also mentions some codes that Marcus van Bavel has created when working with 24P cameras called DVFilm Maker.

John Bryant: Mark, the owner of DVfilm, has written some programs/code that takes the QuickTime film and makes it true 24P. Then, another program he wrote, takes the file and makes a bitmap image of each frame of the film and then it's scanned 2k onto the film negative.

Here's the explanation of the codes from the DVFilm.com Web site. The utility does a 2:3:3:2 pulldown removal in order to get the film into true 24P.

John Bryant: DVFilm Maker allows you to edit in a true 24P time line, using older versions of Premiere, Final Cut Pro, Vegas Video, or many other DV editing programs. Even if you have the latest versions of Final Cut Pro, Vegas, or Avid Express DV Pro, there are features in DVFilm Maker you will find useful, like for converting 24P to NTSC with a 3:2 or 2:3:3:2 pulldown.


Director John Bryant looks on at his new expensive baby.

Any source of NTSC can be converted to 24P, not just 24P Advanced Mode (2:3:3:2 pulldown) , but also 24P Normal (3:2 pulldown), or video which was shot on film (3:2 pulldown), or regular interlaced video (60i), or even PAL. Maker also converts 24P QuickTime back to NTSC video with a 3:2 pulldown. It also can convert 24P QuickTime back to NTSC with a non-recompressed 2:3:3:2 pulldown, for archive to tape, and can then re-convert that tape back to 24P, without recompression-- a feature which is missing from many editing programs that support the DVX100 and XL-2.

When removing 2:3:3:2 pulldown, DVFilm Maker compares every field in the movie to the field in the next frame ahead. It looks for a closer than average match. Since the repeated fields match each other more closely than non-repeated fields, the repeated fields can be identified and removed. In the 2:3:3:2 mode, the removed fields will always happen to fall in the same frame and so the entire extra frame is removed. The movie is output as 23.976 frames per second, and the sound track is copied over as-is.


The reel lies on the 35mm projector platter.

The 35mm print looked great on the big screen. The unfortunate problem is that when projected onto that large of a screen when transferred from a prosumer DV camera, you can really see the difference between a pro lens and the lens on the DVX100A. Everything was in focus, but the image just can't compare to actual film, or images captured with a larger chip camera, or on HD.

Also using the Panasonic AG-LA7200G Anamorphic adapter softened the image a bit when zoomed in on longer focal lengths. I attribute this to the shape of the add-on lens that curves vertically, creating some vertical soft edges when viewed.

Overall the blow-up was a pleasant, if not a bit confusing, process. DVFilm did a great job on the transfer. The sound was crisp and powerful, and very clean, which is critical for making a good film. It was pumped out of a DTS-enabled theater, and while not encoded for 5.1 surround sound theaters, it still carried the punch needed for the drama that unfolds on screen.

I will continue to cover current news of the short film from Sundance, next month, so check back to see the audience response to viewing the 35mm print in action.