[limabean]

Hello,

I was taking some video tests with my new K-x and notice there is quite a bit of noise in the footage. It's like a gain switch is on. My guess is that this has to do with the auto-ISO settings in the camera. I tried to limit the auto-ISO from 200-400 but still no luck. I looked on youtube and saw some K-x night footage that didn't look overly noisy and I was hoping to get similar results.

Anyway... just wondering what tricks there are to bring down the noise in indoor/night shots?

Thanks

[netrex]

I'll be tesing with AviSynth. I did some on DV-footage a few years ago, and it was great. Don't remember much of it now, so I'll have to have a look at it again.

I do think it will give some nice results, more that most other stuff I've seen, at least it used to.

Check the forum at doom9.net for AviSynth, there should be a lot of info about it there. It's all free and legal software.

[jogiba]

http://avisynth.org/mediawiki/Main_Page

http://avisynth.org/mediawiki/FAQ_general_info

[kmlo1984]

Hi,
i find it this way,
1. don't sharpen it too much, do set up the shadow/highlight at max.
2. don;t use shadow in dynamic range, though it flatten a bit, use highlight only.
3. limit the auto ISO ( some says u set at AV and then it will stay) but i find not.
4. use faster lens max aperture opening, to make auto iso goes less.
5. preset at Ev 7, then adjust expsoure compensation, I test at Ev7 has less noise.
6. use software to smoothen. i use virtualdub, and wish to learn script in avisynth.

over all, pentax KX produce a grainy and not so perfect video,
but HEY! it's cheaper than a DOF adapter!!.


take a look of my sample in
my Pentax K-x test on Vimeo

happy new year
KM

[davidvandoren]

I have the same issue.

However I found so far the best results with.

menu: C2 set Af/AE-L to 4

This way you can push the AF AE-L button once you see a desired result in your preview.

WB: and set to White Balance Tungsten light.

This works indoor and takes out most of the grain.

menu: C3 15High ISO noise reduction set to 2

This will start noise reduction at an ISO 400 the green value 1 means 800

menu: C 4 Using Aperture Ring set to 1

before filming turn the wheel till you start seeing the red F8.0 become something like F4.5 and turns white.
Then manually focus and find the right exposure on your screen. The push the AF-L button to lock the Exp.


That's how far I got it in tree days now.

Please ad more settings to this thread.

Thanks

[Christopher M.W.T]

I am of the understanding that auto ISO doesn't affect video mode at all.

[netrex]

I am of the understanding that auto ISO doesn't affect video mode at all.

Do you mean restricting auto ISO doesn't affect video mode? If so, I agree, it seems like that to me too. It's sad really.

[dutch]

5. preset at Ev 7, then adjust expsoure compensation, I test at Ev7 has less noise.

can you explain this a little more?

How do I preset ev 7?

[kmlo1984]

hi
Most light meter has option to read out F stop/shutter combination or just Exposure Value ( E.V.) set at EV this time. if you dont have the option, ask anyone has the meter to give the combination and u work it out.

set iso at 200
if use incident meter, put white ball facing the light source ( i mean for the reading of light value, not to aim at the camera, i generally practicing zone system)
if u get the reading of Ev7, this is it.

for spot meter, get an 18% grey card and get the expsoure.

adjust the light till u get exactly EV7.

happy new year
K.M.Lo

[Christopher M.W.T]

hi
Most light meter has option to read out F stop/shutter combination or just Exposure Value ( E.V.) set at EV this time. if you dont have the option, ask anyone has the meter to give the combination and u work it out.

set iso at 200
if use incident meter, put white ball facing the light source ( i mean for the reading of light value, not to aim at the camera, i generally practicing zone system)
if u get the reading of Ev7, this is it.

for spot meter, get an 18% grey card and get the expsoure.

adjust the light till u get exactly EV7.

happy new year
K.M.Lo

No offence mate but you cannot manually set the ISO on either the K-X or the K-7 they are auto by default, I'm sure faulk has confirmed to on his blog that the AUTO ISO setting has no effect on video.

I've tested it myself and found that it doesnt work either.

[kmlo1984]

No, i m not offended
as I stated already

3. limit the auto ISO ( some says u set at AV and then it will stay) but i find not.

do check other posting, falk and another mapping out the exposure combinations.

i have to deal with overheating and banding /noise issue.
i wonder if it;'s related to over heating.

after all, for 700USD i cant expect too much.

K.M.

[kmlo1984]

the first video is testing on this fixed iso issue.
turn out it;s not possible.

BUT, a work around if u have a say to set up the light to EV7/8/9 at F2.8
pls refer to the charts:

Pentax K-x - exposure
Falk Lumo: K-7 as a movie camera -- PART II: Controlling video recording


I really think pentax should give full manual control
I also find the flicker and color shift at low light dark area

K.M.

[limabean]

so... I was thinking the graininess was caused by the auto ISO (in that it would increase the gain automatically) but then I did a low light test, albeit at f3.5, but I did the AE-L lock (all settings set as they should be, etc.) on a light to get to ISO 200 then turned off everything, then shot the candle at what should be ISO 200 and got some really nasty noise issues regardless...

the video is here...



here's a comparison video... they had a better lens but in this one there isn't any weird noise issues...

http://www.youtube.com/watch?v=lo7C3mjZknM&feature=related

thanks again

[netrex]

so... I was thinking the graininess was caused by the auto ISO (in that it would increase the gain automatically) but then I did a low light test, albeit at f3.5, but I did the AE-L lock (all settings set as they should be, etc.) on a light to get to ISO 200 then turned off everything, then shot the candle at what should be ISO 200 and got some really nasty noise issues regardless...

the video is here...



here's a comparison video... they had a better lens but in this one there isn't any weird noise issues...

http://www.youtube.com/watch?v=lo7C3mjZknM&feature=related

thanks again

I can't say I see much more noise in their video compared to yours. Yours looke pretty noise free for me.

[Voytech]

so... I was thinking the graininess was caused by the auto ISO (in that it would increase the gain automatically) but then I did a low light test, albeit at f3.5, but I did the AE-L lock (all settings set as they should be, etc.) on a light to get to ISO 200 then turned off everything, then shot the candle at what should be ISO 200 and got some really nasty noise issues regardless...

the video is here...



here's a comparison video... they had a better lens but in this one there isn't any weird noise issues...

http://www.youtube.com/watch?v=lo7C3mjZknM&feature=related

thanks again

I see no visible noise in your vid.