Noise in Image at DVinfo.net

Tom Marks · March 15th, 2010, 09:55 PM

Hi,
I'm at loss. There are people out there shooting in dark situations with shutter at 30, F2.8 ISO set at 2500 and their images are clean. I do the same with my 5DMKII and its full of noise. What am I doing wrong? The image is not clean at all. here take a look.

Perrone Ford · March 15th, 2010, 10:03 PM

1. What lens are you using?
2. You should not be at any ISO over 640 if you want it clean
3. Why are you running around like a headless chicken with the camera?

The lens will have a GREAT impact on the quality of the footage. Why people insist on shooting with ridiculous ISO's is beyond me. I shot our film at 160, 320, and 2 shots at 640 where I just couldn't get the light I needed. I wasn't happy with anything else I saw. And lastly, the codec breaks up BADLY with motion and detail. Try to use cinematic moves and you'll see far fewer problems.

Tom Marks · March 15th, 2010, 10:07 PM

im using a 24-70 f2.8.
If i dont go over 640 than what am i really going to capture? A dark room?
I was also testing the glidecam. (So i wasn't running around like a chicken without a head)

Perrone Ford · March 15th, 2010, 10:14 PM

Quote:

Originally Posted by Tom Marks

im using a 24-70 f2.8.
If i dont go over 640 than what am i really going to capture? A dark room?
I was also testing the glidecam. (So i wasn't running around like a chicken without a head)

Put a piece of fast glass on there, and see what you get at ISO 640. A 50mm 1.4 or 35mm 1.8 ought to do. Using a DSLR is not an excuse not to light.

Look at it from a Hollywood perspective. You now have a sensor that is almost the same size as a S35 film camera. The two most common pieces of film used in those cameras is Kodak's ISO 100 and IS0 400 (rated at 320) film. They are using glass typically that is F1.4 or F1.8. In some cases F2.0. They bring lights in moving van or a semi-truck. They light indoors and outdoors. So why people think that suddenly because they have a near S35 sensor they can not use lights is beyond me.

I was somewhat joking about the chicken thing, but you are moving at a speed WELL beyond what your codec can handle without breaking up. Been there, done that.

Tom Marks · March 15th, 2010, 10:18 PM

Ok Thank you. Ill give it try and see what the result are like. That actually makes sense. Im concerned because when your shooting a wedding the venues are dark. I have lighting but I can't go crazy because the client will get upset. So its a hard call sometimes.

Perrone Ford · March 15th, 2010, 10:23 PM

Quote:

Originally Posted by Tom Marks

Ok Thank you. Ill give it try and see what the result are like. That actually makes sense. Im concerned because when your shooting a wedding the venues are dark. I have lighting but I can't go crazy because the client will get upset. So its a hard call sometimes.

No, it's an easy call. Use fast glass. With F1.4 glass, you'll be letting in 4 times as much light as you are right now. At a reception, a 50mm F1.2 or 35mm F1.4 piece of glass should be your best friend. Especially on a glidecam where you can't focus much.

Jonanthan Carr · March 15th, 2010, 11:22 PM

You should remember that this is a CMOS sensor, so your have more noise with tungsten light, rather then with daylight lighting. For ISO, remember that each ISO is only a 1/3rd of a stop of light, that's why the ISO number doubles every 3. These camera's have a pretty decent signal to noise ratio up until ISO 800. I find personally that ISO 320 has the best signal to noise ratio. A fast lens will help greatly with reducing noise with run and gun shooting as long as you can keep focus...

Here's a still from a short film I shot on the 7D.
800 ISO 50mm at f2-2.8 split
http://i49.photobucket.com/albums/f2...at124543AM.jpg

Andree Markefors · March 16th, 2010, 01:16 AM

You can at least go up to ISO 1250 without increasing the noise too much.

Up to and including ISO 1250 is good. After that it increases at bit at 1600 and then pretty quickly increases from there.

However. You put the ISO where you need it to be for good exposure. Simple as that.

Changing aperture changes DOF and thereby the footage. Same with shutter speed. Should normally be kept at 1/60 for 29,97 or 1/50 for 25p or 23.97 (we don't have 1/48).

Using 1/30 is a 'slow shutter' effect- not something you set "because it's too dark".

ISO is our only option really, when it gets dark. We use filters when we want large aptertures in bright light.

Your results do not differ from anyone else's. It's the same camera.

Andree Markefors · March 16th, 2010, 01:23 AM

Just looked at your footage.

I think of it as clean.

Obviously it's a question of what we all consider usable. There will always be some amount of grain. Lucky for us- or me- is that I think the grain has a film like quality.

Your footage is, however, not sharp. I get the feeling you are trying to use some sort of auto focus- there isn't any.

The manual might mention something along the lines of "live focus" or whatever. Not an option. One hand needs to be constantly caressing the focus ring of the lens.

March 15th, 2010, 09:55 PM	#1
Tom Marks Regular Crew Join Date: Feb 2008 Location: Staten Island, New York Posts: 44	Noise in Image Hi, I'm at loss. There are people out there shooting in dark situations with shutter at 30, F2.8 ISO set at 2500 and their images are clean. I do the same with my 5DMKII and its full of noise. What am I doing wrong? The image is not clean at all. here take a look. Noise on Vimeo

March 15th, 2010, 10:03 PM	#2
Perrone Ford Inner Circle Join Date: Nov 2006 Location: Tallahassee, FL Posts: 4,100	1. What lens are you using? 2. You should not be at any ISO over 640 if you want it clean 3. Why are you running around like a headless chicken with the camera? The lens will have a GREAT impact on the quality of the footage. Why people insist on shooting with ridiculous ISO's is beyond me. I shot our film at 160, 320, and 2 shots at 640 where I just couldn't get the light I needed. I wasn't happy with anything else I saw. And lastly, the codec breaks up BADLY with motion and detail. Try to use cinematic moves and you'll see far fewer problems. __________________ DVX100, PMW-EX1, Canon 550D, FigRig, Dell Octocore, Avid MC4/5, MB Looks, RedCineX, Matrox MX02 mini, GTech RAID, Edirol R-4, Senn. G2 Evo, Countryman, Moles and Lowels.

March 15th, 2010, 11:22 PM	#7
Jonanthan Carr Regular Crew Join Date: Feb 2010 Location: United States Posts: 50	You should remember that this is a CMOS sensor, so your have more noise with tungsten light, rather then with daylight lighting. For ISO, remember that each ISO is only a 1/3rd of a stop of light, that's why the ISO number doubles every 3. These camera's have a pretty decent signal to noise ratio up until ISO 800. I find personally that ISO 320 has the best signal to noise ratio. A fast lens will help greatly with reducing noise with run and gun shooting as long as you can keep focus... Here's a still from a short film I shot on the 7D. 800 ISO 50mm at f2-2.8 split http://i49.photobucket.com/albums/f2...at124543AM.jpg __________________ Dp Reel http://www.visualcinema.com/reels/ Rentals in NYC http://www.visualcinema.com/rentals/cameras/ Scarlet-X SN#634 "HEXTALL"

March 15th, 2010, 10:07 PM	#3
Tom Marks Regular Crew Join Date: Feb 2008 Location: Staten Island, New York Posts: 44	im using a 24-70 f2.8. If i dont go over 640 than what am i really going to capture? A dark room? I was also testing the glidecam. (So i wasn't running around like a chicken without a head)

March 15th, 2010, 10:18 PM	#5
Tom Marks Regular Crew Join Date: Feb 2008 Location: Staten Island, New York Posts: 44	Ok Thank you. Ill give it try and see what the result are like. That actually makes sense. Im concerned because when your shooting a wedding the venues are dark. I have lighting but I can't go crazy because the client will get upset. So its a hard call sometimes.

March 16th, 2010, 01:16 AM	#8
Andree Markefors Regular Crew Join Date: Sep 2009 Location: Zürich Switzerland Posts: 81	You can at least go up to ISO 1250 without increasing the noise too much. Up to and including ISO 1250 is good. After that it increases at bit at 1600 and then pretty quickly increases from there. However. You put the ISO where you need it to be for good exposure. Simple as that. Changing aperture changes DOF and thereby the footage. Same with shutter speed. Should normally be kept at 1/60 for 29,97 or 1/50 for 25p or 23.97 (we don't have 1/48). Using 1/30 is a 'slow shutter' effect- not something you set "because it's too dark". ISO is our only option really, when it gets dark. We use filters when we want large aptertures in bright light. Your results do not differ from anyone else's. It's the same camera.

March 16th, 2010, 01:23 AM	#9
Andree Markefors Regular Crew Join Date: Sep 2009 Location: Zürich Switzerland Posts: 81	Just looked at your footage. I think of it as clean. Obviously it's a question of what we all consider usable. There will always be some amount of grain. Lucky for us- or me- is that I think the grain has a film like quality. Your footage is, however, not sharp. I get the feeling you are trying to use some sort of auto focus- there isn't any. The manual might mention something along the lines of "live focus" or whatever. Not an option. One hand needs to be constantly caressing the focus ring of the lens.