The noise is killing me!

This might sound crazy, but try putting two magenta filters on you camera, white balance threw them, and then shoot with them on, this should help you reduce noise in the red and blue channels, as well as give you more useful dynamic range in your highlights.

I use this technique with my DVX Andromeda to great results, I'm assuming it should work fine with an HVX. For outdoor shooting, you can get away with even more filters, I would recommend 3 actually.

More detailed specs can be found here....

http://www.dvxuser.com/V6/showthread.php?t=111384

Hope that helps!
 
Why don't you post a few frame grabs and tell us the settings you used as well as your capture settings in your NLE and we may be able to be more specific in our advice.

Plus we can all learn in the process. Let's see what ya' got : )
 
I'm currently using two of these:

http://www.ritzcamera.com/product/2...ras-and-accessories;cifilters;cifilters-round

I'm also using a UV filter too. I suppose you could just buy one dense filter, but there are some cons, like not being able to slowly build your optimal density up.

I would recommend using the largest filters our there and connect using a step up ring, if you have more money, you could always just use a matte box with filter stages.
 
cardmaverick said:
I'm currently using two of these:

http://www.ritzcamera.com/product/2...ras-and-accessories;cifilters;cifilters-round

I'm also using a UV filter too. I suppose you could just buy one dense filter, but there are some cons, like not being able to slowly build your optimal density up.

I would recommend using the largest filters our there and connect using a step up ring, if you have more money, you could always just use a matte box with filter stages.
Click to expand...

really? so if i stack two of these, and then white balance and shoot through them (to either 56 or 32 light) using the Ach or Bch White Balance on the DVX or HVX, I will have cleaner/less noisy footage?

the tint in the lens doesn't add any grain to the image?

Thanks.
 
Janusz,

Here is a little excerpt from the other post:

"
Lowering gain in the red and blue channels, then pulling the green channel back via the magenta filters to make the channels all even exposure wise, then you can get a strong exposure in all three channels. Without it, red and blue will be underexposed, while green is more fully exposed.

You can't really have an end all be all balance unless you are committed to putting additional CTB or CTO filters on top of your magenta filters. If you balance threw magenta under 3200K, you'll still need CTO to shoot under higher color temperatures. If you balance under 5600K you'll still need CTB filters to shoot under tungsten light.

Optical filtering is a major part of the process, without the filters, this technique isn't really gonna help you out, given that you'll be underexposing and then boosting underexposed data in post.

Make sense?"

Keep in mind this is based off my DVX testing, but I'm pretty sure white balancing works the same way in the HVX, they are very similar cameras in many respects.

As for noise, its all about lowering gain in the red and blue channels, green can't be adjusted, its a constant.

The absolute best results come from using very, very high color temperature lighting and a bunch of magenta filters.

How much noise reduction you see in the red and blue channels depends on the light your shooting under, optical filtration, and the color content of the scene.

Last, but not least, you have to factor in a little bit of mystery.... the DSP! I don't know if the DSP has some kind of noise reduction built in that users can't control or not. Either way, you will at least be making the sensors analog output less noisy, and thats always a good thing.
 
"""what type of magenta filter? like a +/- green (which ever one is pink)? if so half or full?"""(januz)

i have not tested but for now i have seen that -really -when i do WB the green channel never change.
chris said that we have to use a method like viper's camera.
in the viper's manual there is the suggestion to use (for correcting the green channel) and for optical balance a cc60M(magenta filter) + CC80C IF WE are under 3200°k or +CC81B if we are under 5600°k.(http://www.grassvalley.com/wp/cameras/viper/The_Viper_Exposed.pdf)
if this have sense,to have the same green level of Viper's camera i presume that a cc60M optical filter would be the starting point to do WB and to use as camera filter.
about the temperature's color correction i think that we can adjust with the camera setting(for not using too much filter that can degrade the image).
that are only ideas,i have not tested it......but is this a good starting point???
best
ivan

p.s.:chris.....why you don't answer to private messages???
 
thats interesting because, the HVX200 is a 32k native camera. its 56k setting is a DSP color adjustment. its interesting that it gets its best performance when correctin for ble light....
 
TimurCivan said:
thats interesting because, the HVX200 is a 32k native camera. its 56k setting is a DSP color adjustment. its interesting that it gets its best performance when correctin for ble light....
Click to expand...

Are you sure about that? After testing the DVX, I found its optimal color temperature to be threw the roof high, about 12,200K. This is of course with optical filtering and a tricked white balance, but at any rate, that is the color temperature where you can actually manage to get all three channels balanced evenly gain wise, and not need any other color filters in front of your "magenta armada" LOL.

When I did manage to hit that balance, I was quite amazed at how all three channels showed the same amount of noise, and it was really, really low.

As for white balance being a DSP color adjustment, I think thats misinformation honestly. A bunch of people initially told me that the DVX100 did that, but once you tap into the ADC's directly, you can clearly see that isn't true at all. In fact, you can verify this right now without a direct sensor tap. Find a dark red object. Put it under warm lighting, then do a manual white balance. Note how much noise suddenly appears. Thats channel gain your seeing, not a DSP thing.

As for the best performance under blue light, I can see that being somewhat true, especially given the results of my DVX tests. BUT. I find that red becomes more noisy under 56K, which isn't too surprising, there isn't much red in 56K light. The key to getting lower noise in both the red and blue is using filtration, optical correction is the key to success, I can't stress that enough. You essentially create equal gain, and then use filters to pull back the channels that naturally receive a greater exposure, which then allows you to expose the darker channels higher up, and not loose the brighter channel.

Hope that makes some sense.
 
shiny4 said:
"""what type of magenta filter? like a +/- green (which ever one is pink)? if so half or full?"""(januz)

i have not tested but for now i have seen that -really -when i do WB the green channel never change.
chris said that we have to use a method like viper's camera.
in the viper's manual there is the suggestion to use (for correcting the green channel) and for optical balance a cc60M(magenta filter) + CC80C IF WE are under 3200°k or +CC81B if we are under 5600°k.(http://www.grassvalley.com/wp/cameras/viper/The_Viper_Exposed.pdf)
if this have sense,to have the same green level of Viper's camera i presume that a cc60M optical filter would be the starting point to do WB and to use as camera filter.
about the temperature's color correction i think that we can adjust with the camera setting(for not using too much filter that can degrade the image).
that are only ideas,i have not tested it......but is this a good starting point???
best
ivan

p.s.:chris.....why you don't answer to private messages???
Click to expand...

Sorry Ivan, I've been busy, how about we keep most of the questions public, lots of people have been messaging me privately about this stuff , if we stay public, I can cover more peoples bases faster :dankk2:


As for the need to have the added blue filters on top of the magenta filters for the Viper, this only validates my point. They are balanced for a higher than 56K color temperature, maybe they area around 7,000-8,000 Kelvin since they don't need as much magenta filtration. The blue filter is because of the higher balance of the camera. If your balanced for 8,000K.... 5,600K starts to look really orange, and 3,200 Kelvin might as well be pure orange!

Are people starting to understand this?

Ivan, thanks a bunch for posting that link, I've seen it before, but I never thought about posting it as an example of what I'm talking about :thumbup:

The bigger question regarding the DSP is if it employs some kind of noise reduction we don't know about, and at what bit depth certain signal processing is being done at, etc....

Also, as for the cameras sensors, the photo sites are small, which by default, makes them more prone to a higher noise floor.

Hope that helps!
 
TimurCivan said:
i heard it from Jan Crittenden..... just saying....
Click to expand...

Perhaps what she really meant was the 56K preset....

That I can believe.

But manual white balance is another animal, at least with a DVX. I do however see the channel gain change in the DVX when messing with presets though... Remember, I'm largely speculating about how this applies to the HVX, but from what Andromeda has reveled, the DVX seems to have been what the HVX was based off of, even the whole pixel shifting thing, so I'm willing to bet the white balance works the same way. Either way you slice it, the red, green, and blue channels need to be brightened or darkened in some way to create a balanced color image.

OH... just to throw this out there....

Panasonic told the world that the DVX100 was an SD camera....

Just saying.
 
Last edited:
chris,
i think that viper is balanced for 5000°k(if i have understand ),becouse 5600k+CC81B IS LIKE 5000°K AND 3200K+CC80C IS LIKE 5000°K.
IS THIS CORRECT???
MY QUESTION IS:
do you do the white balance only with magenta filter???wich grade do you use now(es:cc30M OR cc60M or more)??
 
shiny4 said:
chris,
i think that viper is balanced for 5000°k(if i have understand ),becouse 5600k+CC81B IS LIKE 5000°K AND 3200K+CC80C IS LIKE 5000°K.
IS THIS CORRECT???
MY QUESTION IS:
do you do the white balance only with magenta filter???wich grade do you use now(es:cc30M OR cc60M or more)??
Click to expand...

No. The very fact that they are using blue filters means the cameras is setup for a higher color temperature. It's kinda weird to wrap your head around this because its so different from "normal" white balancing practice. Just try it. Put like 5 FLD filters in front of the camera, white balance on white under an almost pure blue light, then go outside with the filters still on the camera, and suddenly you'll see why you need a blue filter in the first place, daylight looks ORANGE under this kind of white balance.

The Viper balance is clearly way above typical daylight, thus blue filters are needed for both outdoors and indoors.

You always keep the filters on, especially during the white balance. I estimate I'm currently using 60 ccM for indoors under 3200K, for whatever reason, my filters don't list their ccM... I'm also using a typical UV filter too, which has no real light loss. You can use more magenta for outdoors. Because of the fact that hitting total equilibrium involves a HUGE amount of filtering, I've just opted to go about halfway and not use the blue filters. So in other words, instead of setting up a perfect balance in a controlled environment and then just using various blue filters to shoot with, I simply balance threw magenta, then shoot. It still lowers noise, and its more practical. The perfect balance requires that you always use like about 150 ccM PLUS various densities of blue filtering. This just isn't very practical, even outside, and indoors is just impossible.

Make sense?
 
The HVX200 has also an insufficient IR-blocking-filter in front of the chips, so noise (especially redish noise in black parts of the picture) is also possible from IR-light..... This will be most likely the case with studio lights but even from the sunlight...
 
Correction

Correction

cardmaverick said:
As for white balance being a DSP color adjustment, I think thats misinformation honestly. A bunch of people initially told me that the DVX100 did that, but once you tap into the ADC's directly, you can clearly see that isn't true at all. In fact, you can verify this right now without a direct sensor tap. Find a dark red object. Put it under warm lighting, then do a manual white balance. Note how much noise suddenly appears. Thats channel gain your seeing, not a DSP thing.
Click to expand...


Hey guys, I a made a bit of a typing mistake, its dark green, not red... ops :laugh:

Try that color instead.
 
FIRST:HERE IS ANOTHER THREAT ABOUT MAGENTA FILTER:
http://www.jkor.com/peter/magenta.html
only to make more confusion..........

about IR AND UV protection we can use a filter like B+W 486 Digital UV/IR Blocking Glass Filter .

About the last post of Chris ,if i have understand his optimal process is like this:
use a very blu light in studio to do WB(his optimal setting is to use a light with 12000°k)and then WB a white card under this light with a cc150M filter(5 cc30M filter)and stay with it infront of the camera lens during shooting.this is the optimal setup.

after that, in the real life ,all kind of light are too warm for this setting so we have to use CTB filter in front of the camera lens(different grade depends of the temperature of light) to obtain the same color temperature that we have used during the WB(12000°K)
but this is very light lost.

SO.......MORE PRACTICAL AND HUMAN SET UP IS:
use two or 3 magenta filter and do WB in different color temperature situation depending of your shooting(more blu light is better).
so if we work under 3200°k (if you can use 5500°k light)do your white balance under this light with magenta filter and shoot.
if we go outside and there is a 6500°k light do WB(with magenta)under this kind of light and shoot .and so on............
chris,is this correct????my english is not so good so i have same problem to understand.

my new question now is.:
what is your new exposure method.you still use light meter??or you set the white clipping pont in a scene with your camera and then shoot without the use of light meter.?
can you give more news??
what do you have changed respect this old method ??http://www.dvxuser.com/V6/showthread.php?t=93238

thank a lot
ivan
 
So Timur,

Have you tried out that green white balance test yet?

If I'm right on target with my prediction, it should look really noisy. This is actually how I got into researching the electronic white balance and the viper setup, etc...
 
i found that sometimes, and i cant understand why, but if you use a custom Whitebalance, and you push the Chroma phase WAY to the green side and the Color Temp to way yellow, sometimes the image turns a Perfect Green, or Magenta.

I wonder if that has something to do with it.
 
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