Timelapse from RAW to HD

[Sanjin Svajger]

Hi all,

I'm doing research about doing a time lapse. It's going to be used in my documentary. What I'm worrying is how is a time lapse from 7D taking RAW stills going to convert to HD video!?

How do you folks usually down convert 7D stills to HD video without getting aliasing and moire?

*Edit: Or would it be better to shoot jpg?

Thx

Br
S

[Jon Fairhurst]

Shoot full sized RAW, if you have enough memory space.

You can use Digital Photo Professional to save a "recipe" to the clipboard and then apply it to all your photos. You can do a batch save of 1080p JPGs.

In Vegas, I set the time per photo as 41.708ms. I can then just drag all the files to the timeline and they are stacked, one frame at a time at 23.976 fps. Use 40ms for 25fps.

Personally, I like smooth, rather than stuttery, timelapses. I use an ND 0.9, three stop ND filter or stronger. I set the shutter time close to half of the interval time. I set the aperture to f/16 or so on a wide lens. ISO is 100, if not 50.

With such a small aperture, I strongly recommend setting the exposure, holding the DOF preview button, and unscrewing the lens slightly. This sets the aperture to a fixed size and eliminates flicker. Otherwise, the shutter opens and closes between snaps, and the actual aperture will vary shot to shot, causing visible flicker.

Also, I set the Live View mode to Stills Only and shoot in Live View. This locks the mirror so it doesn't slap up and down.

Best of luck!

[Daniel Browning]

Originally Posted by Sanjin Svajger

How do you folks usually down convert 7D stills to HD video without getting aliasing and moire?

There are about a bajillion options, so it's hard to choose some times. Here's a few examples:

• Cineform:
  + Convert the raw CR2 files to Cineform Raw with the $300 Neo (use DPX2CF and ignore the name).
  + Optional: Use First Light to tune the raw conversion (white balance, demosaic, etc.)
  + Optional: Generate cineform proxies if your system is too slow to edit the raw files directly.
  + Edit the raw files directly in the editor of your choice at the maximum possible 12-bit quality.
• Adobe:
  + Open raw files in After Effects
  + Optional: Tune the raw conversion (white balance, etc.)
  + Optional: Render out for an online workflow if your system is too slow to edit the AE sequence directly
  + Open the AE sequence in Premiere Pro at the maximum possible 12-bit quality.
• Other:
  + Convert all the raw files to TIFF, PNG, or JPEG using the raw converter of your choice.
  + Use a photo-to-video converter (e.g. After Effects or VirtualDub) to make an online video file in some format.
  + Edit the video file in whatever quality you were able to achieve.

The benefit of the Cineform solution is that it's the only compressed raw option. That makes it fast enough to keep the raw through the entire workflow without another intermediate, and the ability to change something and have it reflected immediately. The downside is that First Light may not produce exactly what you're looking for from your raw files, in which case you'd have to render out from raw anyway.

The benefit of the Adobe solution is similar to Cineform -- you can complete the entire workflow without rendering out from raw. The difference is that it uses the original uncompressed raw, so it's a lot slower and generally requires that you wait for the cache to refill after making any changes.

The "other" method usually results in losing significant resolution and/or bit depth before you even get to the point where you can start editing it. If you convert to 16-bit TIFFs, load them in After Effects, then convert to a 12-bit 4K cineform, then you're in good shape for both resolution and bit depth. But if you use something like VirtualDub, which only supports 8-bit, then you lose a lot of flexibility. Plus, many otuput formats such as DnxHD only support up to 1080p, so you lose a lot of flexibility for zooming and panning the image in post.

In short, the best workflows that I know of are either Cineform Raw, Cineform 4K, or Adobe.

[Sanjin Svajger]

Thanks for the reply Daniel!

Think I'll go the Adobe route:) I have 24gigs of ram, so this will be, a nice test for my workstation.

I understand all that you wrote but still don't understand how do you resize to 1080p... Or is this not such a problem - do you just adjust the frame size when exporting the video?

[Daniel Browning]

Originally Posted by Sanjin Svajger

I understand all that you wrote but still don't understand how do you resize to 1080p... Or is this not such a problem - do you just adjust the frame size when exporting the video?

Yes, ideally the resize isn't done until the final export. The easiest method will be to let Adobe do the resizing for you in Adobe Media Encoder.

As for me personally, I'm really picky when it comes to resizing software. Most people will prefer to just use Adobe Media Encoder, but for me personally, I prefer the resizing algorithms in other programs, so I would render out an uncompressed version and then resize. My favorite resizing program is ImageMagick, but it's a huge hassle to render out as an image sequence, resize, then render back to a video file. My second favorite is After Effects, which is faster and still has a lot of options. Next is avisynth, then VirtualDub, and after that it's Adobe Media Encoder.

Have fun!

[Sanjin Svajger]

I see. Interesting. I thought that folks used some kind of special resizing method. Because resizing from 5 or 6k to HD is quite a big leap.

Anyway, I'll try it and see how it goes:)