Canon 70d video modes help

LauraJ23

LauraJ23

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Hi all, looking for some help with all of the different settings in the video quality area of my 70d

Now I know full hd is obviously 1920 x 1080. I have two settings for this

24fps with either
low comp (all-i)
High comp (ipb)

What is the difference when I go to 1280 x 720 at 50 fps again with the same two options above.

If I wanted to slow the video speed down, is it doable with the 70d?

All help greatly appreciated!
 
What are the respective bitrates? I'd expect the I-frame only codec to be significantly higher than the other. If not, it will be much worse quality.

I-frame only sends an image for each frame (like a JPEG) and is relatively easy to edit.

IPB uses I-frames every second or two and uses Prediction (P-Frames) and Bi-directional Prediction (B-Frames) on the other frames. This provides much lower bitrates for a given quality but is more processor intensive to decode.

Does it not do 25 fps which would be the European video standard?
 
1920 x 1080 (29.97, 25, 23.976 fps), 1280 x 720 (59.94, 50 fps), 640 x 480 (59.94, 50 fps) from dpreview and this from imaging resource
Other video specs of the 70D are fairly standard fare for Canon DSLRs. Like the 60D, there's Full HD 1,920 x 1,080 resolution video at 30p and 24p (for NTSC, 25p in PAL mode), plus 720p HD video at 60p (50p PAL) cant seem to find a bit rate
 
24 is the traditional film rate, 25 or 50 the video rate.

24 will give you more issues, lighting flicker, TVs not accepting it etc.

You can always slow a video down - but it will judder. Pro slowmo cameras are 300 fps.

For reference, AVC-Ultra I-frame is 100Mbps, IBP is 25 - so expect a 4 to 1 difference for similar quality.
 
I-frame is 85 Mbps, IPB 30 Mbps.

Go out and shoot some finely detailed moving items, like leaves in a breeze, ripples on a pnd.

Then judge which looks best.
 
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