View Full Version : T2i Motion Problems

07-25-2010, 01:27 AM
So I went out shooting and I've discovered at least one example of a motion problem I cannot explain. T2i on tripod shooting 1080p24. The shutter speed was really really high because I don't have my ND yet. I was using a Transcend 32GB class 6 (don't know if that could be the issue- like I need class 10 or something). It is strange because the problem is in a place without much motion. In this 5 second clip, check out at second 2, as he leans back the motion stutters (it was like this in FCP at full res so I through it up on YouTube to show you all). Watch it in 720p to see what I mean; this is NOT just a compression issue, it looks like that in the full res uncompressed. I don't think it is related to shutter speed because you can see for the rest of his motion it looks fine (though overly fast and non-filmlike because of the high shutter). Anyone had problems like this? Solutions? Thoughts?

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07-25-2010, 05:29 PM
Class 6 aught to be more than capable...and transcend are a reliable make.
Sensor over-heating maybe? How long had you been shooting for by this time?
hmmm, bit scary really. Anyone know what the actual native 'clock' frequency of the chip in the T2i is? Or does it have separate dedicated frequency sources for each frame rate?

Just bought a T2i myself; cheers for all the postings ShortnStout.

07-26-2010, 11:07 PM
Thanks, EG! Yeah, I hadn't been shooting all that long. I'd say this was at the earlier end of my shoot so less that 1/2 hour and not continuously. I also find this scary because this is the sort of thing you would not know went wrong until later. If this were a commercial type shoot it were a necessary shot and you thought you had it covered it would be a big problem.
I hope somebody has some answers.
Besides this issue I'm really happy with the camera. But this is a big issue for me.

08-16-2010, 10:08 PM
This article (http://newportpictures.tv/blog/?p=19) is about slow mo, but it explains shutter speed in it for you. Hope it helps, it's easier for me to link than to explain it all to you. haha sorry.

08-25-2010, 11:09 AM
Since you are using FCP, I'm guessing you transcoded this into prores or something. Perhaps this was a hiccup in the transcoding process. You don't have the original h.264 files from the camera still, do you? See if the artifact is in that footage to eliminate the possibility of a bad transcode. I've seen issues like this when renderinr or playing back highly compressed video of the CPU is set to increase and decrease clock speed/voltage as required by processing demands. I have found that disabling any cpu throttling has eliminated any wierd stutters such as this from my system running preimiere cs5

El Director
09-04-2010, 07:59 PM
Looks to me like you used too high of a shutter speed. Best to leave it at 50 or 60 depending on your framerate

09-21-2010, 07:53 PM
Remember to adjust the f-stop for your exposure and lower your shutter speed. Also if you are shooting at 24 p and be sure that your time line in FCP is set to 24 p as well. if you are editing in a 30 or 60 frame rate it could cause some visual issues.