View Full Version : Video noise


Joe Boland
May 4th, 2010, 03:11 PM
Hi Guys, I have the wonderful sony z7, lovely cam, again like a post that was here a short time ago, i can get quite a bit o noise in my film mostly at dancing when lights are low at weddings, i have used the 6 -9 db gain but still only ok, when i go on auto its realy bad. i had a dsr 250 before and you could use it in a barn

any help for the Irish man would be wonderful

thanks guys

Joe

Lee Berger
May 5th, 2010, 03:49 PM
Hi Joe,
As an HD Camera the Z7 is much better in low light than it's predecessors such as the Z1 and the V1. It's still a high def camera with 1/3" chips, compared to the 250's 1/2 inch chips. If you went auto you may have experienced auto gain which can up the gain as high as 18db. I have found 12db useful in some situations, and 9db reasonably acceptable for event shooting. I shot a wedding reception last week and I was able to safely place three tungsten lights and bounce them off the ceiling. That allowed me to shoot at 0db. Some venues are not conducive to adding light. I hope this is helpful.
Lee

Oops. I got the 250 mixed up with the 300. Sorry about that.

Don Bloom
May 5th, 2010, 04:39 PM
the DSR250 was a 1/3" chip camera. Basically a PD150 in a fullsized body. It worked great at 15db if need be but of course so did/does the 150-170. I have owned them all and frankly the DSR250 or PD150/170 is/was better in low light situations than the JVC5000 I owned which was a 1/2" chip camera. Of course some of that had to do with the lens on the JVC which was the Canon 16X, the Canon 19X was far and away better but regardless, the Z7 should be just fine at 9 in a pinch even 12 it depends on the rest of the setting you're running with, ie; shutter speed, f/stop, etc and of course are you relying solely on existing light or are you helping it with some on or off camera lighting.

Wesley Cardone
May 6th, 2010, 07:33 AM
If you discover noise in the edit room there are various de-noise softwares that help very much in taking out the noise. One might suggest that this process could be extended to essentially increase the light gathering capabilities of your camera but I don't recommend it. Sure, you can shoot at a lower gain and collect insufficient light but then correct it in the edit room. However, de-noise is not perfect and you are probably no better off than if you just upped the gain in the first place. De-noise processing adds a huge amount of overhead to your workflow as well.

De-noise software, though, is a life saver when you are caught by surprise.

Bryan McCullough
May 6th, 2010, 08:24 PM
2 days ago I spent the best $100 I ever have in this business. I bought Neat Video and it's incredible at cleaning up noise.

Neat Video - best noise reduction for digital video (http://www.neatvideo.com/)

Wesley Cardone
May 7th, 2010, 05:09 AM
I also bought Neat denoise software and have had great success with it when I used it to save my behind one time last year. This was footage that was captured with a crushed black backdrop in the background which ate up all of the light. It requires that you get a sample profile of noise from your footage that you need to correct. You collect a profile from somewhere on your footage where you have a nearly full screen of maybe a wall or just a blank spot where ONLY the noise is present. My footage didn't really have a good blank spot. However, I used the sample profile that came with the software and it did a really good job.

Joe Boland
May 7th, 2010, 07:00 AM
Thanks guys

Great to get help when stuck,

Lee : I know some rooms can be v dark for weddings etc, and we dont want to turn the place in to a flood lit area, and i did not know the gain could go to 18db on auto ! which is way to high, last week i used Manualand went to 6- 9 db which looked better , i also had a camera top light 100w, so worked out better,

Don: i only used the gain 6-9 i not use the shutter speed, f/stop, etc and was relying solely on existing light in the room, which was ok but .....had to use my camera light later,it looked fine on my lcd .......... but pure horse dung on a lager screen,

Wesley i might give the soft wase a shot as well. that could come in handy,


But as i was so use to the 250 shooting in near dark, the z7 just needs a bit more running,


thank you ALL for you help.

again i need to get to grips with f/stops. shutter speed.


also is there a way to turn down the gain in auto so it dont go to that when on auto. or is this a dumb Question

Wesley Cardone
May 7th, 2010, 01:52 PM
In the menu you can limit how high the gain is allowed to go in auto mode.

You really need to stay away from this auto stuff, anyhow. It will get you into trouble so many times it ain't funny.

I recommend that you consider shooting at a shutter speed of 30fps for things like receptions. The LCD imaging is not a good representation of what your 30fps video will look like. When you think about it, 30fps is really perfect for events such as receptions. The viewer will never know you were shooting at that speed unless somebody makes a sudden move. The benefits are you don't have to up the gain as much meaning less grain in the image. If you can get less overall grain at the expense of an occasional fast-move showing up you win. In practice I have found that fast-moves show up only on rare occasions. 30fps is my standard setting for receptions.

Joe Boland
May 8th, 2010, 05:21 AM
OK Guys I have set the agc to 15 , got a wedding to day so I will let ye know tomorrow, also downloaded the

Neat Video - best noise reduction for digital video , great bit of software,

thanks again

The Irish man

Rob Morse
May 8th, 2010, 11:03 AM
Joe,

15 on the AGC is too high in my opinion. It sounds as though you're using the gain in manual and everything else in auto, is that correct? Neat Video is a great product but I use that when I get footage from other people, not on my own. While it is a life saver, It takes forever to render. You should be able to tell on your monitor whether the lighting is sufficient. I'm sure you know what you're doing but If you need to be unobtrusive lower your light and get a little closer. Also, using the manual settings will give you much more flexibility. I try to shoot with a maximum gain of 9 and do so reluctantly. Also, I've lowered the lighting on the LCD. I think the default is too bright and slightly misleading.

Joe Boland
May 9th, 2010, 07:55 AM
Hi Rob, yea did the wedding yesterday,

yep, you are right 15 is to high in agc, even in the church when i zoom in on say a black suit i could see grain, so i may drop it back to maby 12- 9 and see how it goes,

Yes when i go on manual its only to drop down the gain to help me out.

and yes the default on the lcd is and i set it last night as well.



"know what you're doing" i often wonder, i have been doing weddings for years but with the old ms4 / ms5 and sony 250 you could drive it with your eys closed,full auto and away i go!

Wayne Dear
October 6th, 2010, 04:15 AM
Hey joe,

I had this issue a few months back, looks great in LCD, but crap when you go to edit, and even more so when you veiw on a big 50-60 inch Plasma, the noise is awfull. Yes I was filming in Auto, I soon changed and now do all my shooting in manual, and as above I shoot at 6-9 and 60 fps I think, just depends on light.

I had a shed wedding last week, one light, a flood light, shooting from front to back, bridal at back, was darkest wedding I have shot in 14 years of shooting, and I have done alot of weddings, and I was like, hope this comes out ok... Shot it at 6 and 60, and it was perfect.

Also a trick I do, as the LCD can be deceiving, as it may look fine, but it isnt, I look for a black object, and that way I can see the noise clearly, then I drop the db until its perfect and none is showing, works a treat I find.

I find now though I am allways around 6-9db at receptions with dimmed lights, I do have a light for camera, but alot of people I find do not like it, and one of main reasons I bought this HDV-Z7 was for low light filming of weddings, and it does a really good job if you get your settings right. but some lights can be really good with a nice filter on them and do not become obtrusive.

Rob Morse
October 6th, 2010, 01:25 PM
I'm sure if you told the bride the video would be much higher quality with a little light, she would tell you to go for it. At +9 db I still cringe if I can't get any additional light. Although, some people might be happy with that output.

Dan Crowell
October 7th, 2010, 05:48 PM
Joe,

Try shooting in 30p or 24p and drop the shutter speed to 1/30 or 1/24 respectively in low light conditions as you have described. I personally would never use the gain, but on this camera I think 6db is very clean. I think you'll find the result to be very solution.

Joe Boland
October 8th, 2010, 04:24 PM
Hi Guys, when I first posted about video noise in the z7. yea it was on auto 18!!! and i did my first wedding on this setting ,but I now use 6-9 and i feel its working out great,

Good point Dan with your point in shooting in 30p or 24p and drop the shutter speed to 1/30 or 1/24 respectively have a wedding tomorrow and will give it a go,

Great trick Wayne with the trick LCD going to give that a go to !


Thanks for your help guys

Joe............... all the ways from Ireland

Dan Crowell
October 20th, 2010, 06:28 PM
Joe, How'd that wedding turn out? I'm curious as to whether you opted for shooting in 30p or 24p? Shooting in either frame rate and dropping the shutter speed to match the frame rate should give you very clean and respectable image.

Joe Boland
October 21st, 2010, 12:55 PM
Hi Dan/.

I shot in 24p. and shutter speed to 1/24, nice clean picture, and yes 6 db is clean but with 24p 1/24 much nicer picture, going to keep it at that, love the Z7, its a great cam for its size, just bought a led. 126 light for it , I dont like useing much light but there is times when the hotel/ band turn them down just to much,

Great points there Dan ,


Thank you

Joe

Dan Crowell
October 21st, 2010, 05:57 PM
Joe, great news....love to hear it! I shoot primarily in 30p which only makes it easier to convert to 60i. Glad I could help. Don't be afraid of plying around with different setting. You'll be surprised at how much you learn. Of course, test them out before using them on a real shoot...

Wayne Dear
October 25th, 2010, 05:41 AM
Ill have to try those settings myself and check results, I just did another Wedding weekend just gone, and shot it @ 1080i Shutter Speed @ 50, and kept my gain around 0-6db, 6 being when they turned the lights off on me halfway through bridal dance, but DJ had good bunch of colours going, then when that bit was over I took control of the lights and bumped table lights up and left dance floor dark, results came out really good :)

Wesley Cardone
October 25th, 2010, 07:57 AM
Joe, great news....love to hear it! I shoot primarily in 30p which only makes it easier to convert to 60i. Glad I could help. Don't be afraid of plying around with different setting. You'll be surprised at how much you learn. Of course, test them out before using them on a real shoot...
I think that 30p is the clear choice to shoot natively in as long as your delivery is only going to be 480p30. The disadvantage with 30p, though, is that even though your footage is native 1080p30, there is no Blu-ray option for it. Therefore I always shoot in 1080p24 even though 30p has a slight edge on it.

Dan Crowell
October 25th, 2010, 06:48 PM
Wesley,

These days no matter what format you shoot in, once placed on the time line you output what ever format you'd like.Regardless, I'm not sure what the problem with outputting 24p to Blue-Ray is? Most every modern TV can display 60p, 30p and 24p.....

Wesley Cardone
October 27th, 2010, 09:16 AM
It's not the TVs. Its the Blu-ray standard. It will allow for 60i and 24p but not 30p.

Dan Crowell
October 27th, 2010, 07:01 PM
Haven't done the Blue Ray thing yet.......will have to give it a go! I shot primarily for broadcast.

Zach Love
October 28th, 2010, 09:14 AM
It's not the TVs. Its the Blu-ray standard. It will allow for 60i and 24p but not 30p.

I'd prefer something shot on 30p output to 60i, than something shot 60i just because it will be output to 60i.

I think modern software is up to the task of converting stuff pretty well, even 24p to 60i.

Also in the Blu-Ray world, at least with FCS 3, you can burn a short Blu-Ray movie (through Compressor) on a regular DVD-R with a regular DVD-R burner as long as the file is able to fit on the disk. Pretty sure it would work with other software too. Something I just stumbled on by accident once, but very happy now to be able to easily watch a short HD piece I made on my HDTV & PS3.