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Grainy Image on Canon Rebel T3i

BibleWarrior
Contributor

I bought this camera used, and I have seen test videos that show crisp, clear video on the T3i, but when I bought mine, there is a certain graininess about the quality of the video and photos that doesn't seem right. It almost looks like hundreds of little red dots. is this an issue with the camera, or is it normal?  

7 REPLIES 7

kvbarkley
VIP
VIP

Can you post an example image?

Are you using plenty of light to take the image? Try going outside in good light and take a snap in green square mode.

BibleWarrior
Contributor

This is what it looks like on the video setting, which I am most concerned about since I bought it for making short films. Do you see the reddish graininess?This is what it looks like on the video setting, which I am most concerned about since I bought it for making short films. Do you see the reddish graininess?

That's color noise.  There's also cyan and green in there along with the red/magenta.

What lens are you using? And what are the settings for your videos? In terms of shutter speed, it's typically best to use half of 1 divided by the frames per second value.  e.g if shooting at 30 fps, set the shutter to 1/60 s.

The sunny 16 rule though states that a decent exposure is around f/16, 1/100 s and ISO 100.  In this scene, it appears you're in either sunrise or sunset, so if the aperture is around say f/8 or even f/5.6, there should be enough light to keep your ISO low.

Having said all of that, it could just be that the T3i just cannot capture good quality video.  Notice the softness in the frame of what you provided.

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Ricky

Camera: EOS 5D IV, EF 50mm f/1.2L, EF 135mm f/2L
Lighting: Profoto Lights & Modifiers

BibleWarrior
Contributor

Canon EFS 18-58mm lens, AWB auto, Raw+IL, 24ps, ISO 6400. So, is this a fixable problem, or should I just return it?

The video would definitely not be RAW.  The "RAW+L" that you listed is referring only for Photos.

Agreed with Steve in that ISO 6400 will lead to a very high amount of noise.  What shutter speed and aperture were being used for this video? Perhaps the shutter speed was too high or aperture to narrow.  That would explain why the ISO was so high.

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Ricky

Camera: EOS 5D IV, EF 50mm f/1.2L, EF 135mm f/2L
Lighting: Profoto Lights & Modifiers

stevet1
Authority
Authority

 BIbleWarrior,

I read several articles that recommended that you not exceed an ISO of 1600 on a Canon T3i.

You can do a Google search for "Best ISO for a Canon T3i", and you'll see what I mean.

At 6400, the noise is pretty bad.

Steve Thomas

Thomas68
Contributor

On my Canon T6s I use iso 400 for outside. I know everybody says to use the lowest iso, but mine works great at iso 400. Inside I usually use the auto iso.

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