Ratios?

[Dustin Waits]

35:1, 24:1, 5:1, 1:1, I probably got them all wrong but what does it all mean? Is there a web site that explains all of this?

[Ken Tanaka]

What are these "ratios" in reference to?

[Alex Taylor]

I'm guessing shooting ratios?

In that case, those numbers refer to the amount of minutes shot for every minute in the finished film. I think the average shooting ratio for a narrative feature is 5:1. That is, for every 5 minutes of footage they shoot, 1 minute is used in the version you watch. Documentaries are much higher because you obviously shoot much more and make the story in the cutting room.

[Dustin Waits]

Here....

http://www.avid.com/video/index.asp

Scroll down to the thumbnail that says "seamless integration" and click it to view it. It will show you what I mean.

[Robert Knecht Schmidt]

They're digital data compression ratios. The DV standard is 5:1. 1:1 means "uncompressed."

Impressive product, BTW. But still all SD...

[Rob Lohman]

Compression ratios indeed. A 5:1 compression ratio means that
the signal is compressed 5 times more then uncompressed. So
if you original uncompressed (1:1) footage was 50 MB in size
your footage would be 10 MB in size with a 5:1 compression
system.

The higher the first number the higher the compression and
the lower the quality (usually).

[Dustin Waits]

Cool thanks for the info!

[Adrian Douglas]

Dustin,

The ratios are infact compression ratios as everyone has said but there are a number of different things expressed by different ratios. On the Avid site for instance there are 2 that might concern you. One is the 5:1 DV compression ratio. This is the amount of in-camera compression for the MiniDV/DVCAM standard. Basically it means that the information from the CCDs is compressed at a ratio of 5:1 before it is saved to tape. The other one that may interest you are ratios like 35:1, 24:1, and 15:1. These are offline editing ratios. "Offline" editing is very basically a low quality/low resolution "rough draft" of a piece where the editor puts the shots into the general order of the story. There are no transitions, effects, or titles done this is all done in the "online" edit at full resolution. The different resolutions are for different source origins like film, HD, SD, etc. Offline work is usually done to save online time and therefore money. The offline process produces what is called and "EDL" or "Edit Decision List" which is then imported into the online NLE. The editor can then fine tune the scene sequence and add transitions, effects, and all the other bells and whistles.