Noise reduction always active on the EX1?

[Piotr Wozniacki]

I have posted this comparison on the nanoFlash forum:

http://www.dvinfo.net/forum/converge...ml#post1533919

I'd be curious to know EX1/3 owners opinions, hence linking to it here as well.

Do you think some strong noise reduction is always active in the EX encoder, which cannot be adjusted or turned off with any of the PP setting? This is currently my only explanation of how much noisier the HD-SDI output is, compared to the camera's own encoding... The noise reduction circuit obviously not working on the uncompressed stream, the graininess contained in it is amplified by the nanoFlash higher color resolution, and what we're getting is an even more grainy picture from the nano!

Or do you think something is wrong with my EX1 unit HD-SDI output?

[Vincent Oliver]

It looks like JPEG compression to me, to make the test valid you should post a section of an uncompressed file format such as TIFF

[Piotr Wozniacki]

Agreed, the pictures I posted are jpeg - but this is true of both versions (EX1 and nanFlash - encoded).

[Vincent Oliver]

Fair coment, but in my experience a file that has a lot of detail will look worse when it has been JPEGED, a file with less detail will look better as a JPEG. Just a thought, but I am sure you will have thought of all this

[Piotr Wozniacki]

Yes Vincent, I have thought of this.

However, if I posted any pictures (or created that other thread in the first place) was because of what I saw on my 50" HDTV, as a moving picture - both versions straight from the EX1 and the nanoFlash, recorded simultaneously.

Believe me or not, but the actual difference between the 35 Mbps 420 and the 180 Mbps 422, is even more striking then between their jpeg screen grabs respectively...

[Alister Chapman]

The very act of compressing a signal will reduce the appearance of noise as part of the compression process is to discard some picture information, so noise often gets "smoothed out". So it's not unusual to find a compressed image that appears less noisy than an uncompressed one.

However I rarely see a huge difference between noise in my 35Mb footage and NanoFlash footage. What are you using to decode the files?

[Piotr Wozniacki]

Thanks Alister for your valued comments.

Yes I realize (and have expressed it in the other thread) that it might just be the more severe compression of the EX1 original that is smoothing out fine detail along with some noise, while the high bitrate nano compression exaggerates it (well, perhaps just leaves it intact, I should say). But I'd never suspect this may lead to this kind of unacceptable results!

The EX1 being noisy enough, it's the last thing I'd like to do with my nanoFlash - to exaggerate the low-light noise even more...

As to decoding question - do you mean my NLE I took the grabs from? Well, it's Vegas Pro 9.0.

But please keep in mind that now that I have first noticed it, I can see more noise in some nanofiles (when compared to the original EX1 files) when I watch them outside Vegas, as well - using Sony XDCAM Viewer, or VLC.

[Piotr Wozniacki]

Those interested in the development of this little investigation of mine are welcome to read the thread on the nanoFlash forum at http://www.dvinfo.net/forum/converge...ml#post1533919

Piotr

[Piotr Wozniacki]

Frankly, I am a bit surprised there are no comments on the subject - for the EX series camera users who happen to record to the nanoFlash as well, establishing the optimum settings of both the camera and the nano bitrate is essential!

[Vincent Oliver]

You have two comments, from Alister and myself. Maybe other users are not shooting in low light situations and therefore are not experiencing the same problem.

[Olof Ekbergh]

Hi Piotr,

I have noticed the noise myself several times in low light situations, sometimes even in fairly well lighted scenes. Both with NF and 35mb/s SxS recording. On my EX3 and EX1R.

I think for an inexpensive camera this is still a very good. Betacams and even 16mm film used to be much "grainier".

Have you ever looked at the P2 cameras, they are way noisier.

The high end cams 800 and 900 Sony series are much better and more expensive too.

Every camera is a compromise. When I first got my EX3 I spent a lot of time messing around with PP's. But for production reasons I finally settled on one that works for everything, for me anyway.

If someone comes up with a PP that works very well in low light I would love to try it. I am just to busy to spend a lot of time experimenting right now anyway.

I usually go into Color or AE to fix footage that I am not real happy with, in post. They can both do wonders. I sometimes even add grain for effect.

It would be great if someone was to come up with a list of PP's, kind of like a list of film stock and its different properties and uses, including using the SDI out. But this is a formidable task and very subjective.

Maybe this is something you would like to tackle Piotr. Keep us posted.

[Piotr Wozniacki]

Originally Posted by Olof Ekbergh

Hi Piotr,

I have noticed the noise myself several times in low light situations, sometimes even in fairly well lighted scenes. Both with NF and 35mb/s SxS recording. On my EX3 and EX1R.

I think for an inexpensive camera this is still a very good. Betacams and even 16mm film used to be much "grainier".

Have you ever looked at the P2 cameras, they are way noisier.

The high end cams 800 and 900 Sony series are much better and more expensive too.

Every camera is a compromise. When I first got my EX3 I spent a lot of time messing around with PP's. But for production reasons I finally settled on one that works for everything, for me anyway.

If someone comes up with a PP that works very well in low light I would love to try it. I am just to busy to spend a lot of time experimenting right now anyway.

I usually go into Color or AE to fix footage that I am not real happy with, in post. They can both do wonders. I sometimes even add grain for effect.

It would be great if someone was to come up with a list of PP's, kind of like a list of film stock and its different properties and uses, including using the SDI out. But this is a formidable task and very subjective.

Maybe this is something you would like to tackle Piotr. Keep us posted.

Dear Olof,

As I mentioned in quite a number of threads, noise is probably the Achilles' heel of the EX series cameras. I'm aware those cameras are nevertheless probably the best offer below $10,000, and I love mine - but the fact remains, and you know it. While most people were trying to develop their PPs mainly for on-camera color tweaking, I spent considerable amount of time and effort on finding settings that would let me minimize the noise! As to color, I believe it's best done in post - CC is simply an exciting, creative domain on it's own, allowing a colorist to experience a truly artistic adventure.

Considering the above, no wonder that when I first noticed the nanoFlash can actually make the noise even more problematic (sometimes, even to the extent of becoming unacceptable), I knew I just had to invest even more time and effort to learn the true nature of this phenomenon, and possibly find some solutions. Even though some people are finding my thread http://www.dvinfo.net/forum/converge...ml#post1533919 "bizarre", I believe I succeeded in identifying the issue, and proposing some remedies with EX-series camera users in mind. Again let me stress that - just like I love my EX1 - I'm still very enthusiastic about my nanoFlash, and the issue presented in that thread, nor the nanoFlash usage limitations I recommend (and am going to follow myself), didn't change this attitude.

While we're at it, please forgive me the following, perhaps a little too personal, remark: due to my physical disability after the series of neck spine surgeries (which I'm afraid is going to be permanent), I'm slowly getting used to the awareness that my superb EX1/nanoFlash combo might be the last piece of video gear I'll ever afford to possess in my life. This awareness makes my attitude towards these devices even more emotional - so I wouldn't like anyone reading my posts about their shortcomings to think I'm bashing Sony or Convergent Design, or splitting hairs in order to find issues where they don't exist...

As to the suggestions in the last part of your post (about camera tweaks that might be effective in eliminating grain, particularly in connection with the nanoFlash high data rates) - well, I'll certainly be looking for ones, and - as soon as I find some really good solution - I will share it with the folks here. My problem however is that I do not have any professional devices to help me do it in a more "scientific" fashion - I have to judge results using my eyes only, while watching my video on a high quality, 50" plasma with absolutely neutral image settings.

The current status of my investigation into reducing noise is following:

Unfortunately, the detail settings of the EX1's PP (not just detail, but also frequency, black/white limits, and crispening) - while certainly able to influence the intensity and looks of the grain - can not eliminate it completely. Therefore, I'm using another, crude approach:

As we all know, it's the poorly lit areas (falling into the IRE range between low to medium) that tend to be particularly noisy. Therefore, when I am unable to apply enough lighting to the scene, I do one of the following:

- either crush blacks, so that such areas become completely dark (masking all noise, and - unfortunately - also most detail), or do the opposite, i.e.:

- stretch blacks, so that the problematic areas shift towards higher IRE, which makes the noise less pronounced while retaining details (the disadvantage being a flatter, washed-out picture).

I have my own PPs for both above effects, and sometimes use them as the last resort. More often, however, I do it in post as - along with CC and levels correction - this can be done as a part of the creative process of achieving a certain "look", according to my artistic vision adopted for a given project/material.

Well, I guess this has been quite a long post, so I'll finish now by saying that I'm open to all ideas of the great people on this forum, who - like me - are using the EX/NF combo and are trying to achieve the best results possible - from both technical, and artistic point of view.

[Piotr Wozniacki]

Just wanted to share with you guys, that we should all realize again, and indeed appreciate how great the EX-series cameras codec, and the internal compression performance are...

This is one of the many conclusions one can draw from the http://www.dvinfo.net/forum/converge...ml#post1533919 thread....

[Voitto Saksa]

As you said there is too much noise in EX3 SDI signal. The problem is in the cell. I am disappointed with EX3 signal to noise ratio. The brochure says something else.

I have locked the gain to -3dB position. I get the best results by exposing the pictures as high as possible without saturation. So I need a lot of lamps with me where ewer I go.

In the post I set the offset a little bit lower ( to 16) and adjust the light again if needed and the noise is away.

I have Fujinon HA23x7,6BERD 2/3” lens with adapter in EX3 and NanoFlash recorder and in good lights the result is really nice. In low light the result is unusable.

[Piotr Wozniacki]

Originally Posted by Voitto Saksa

In the post I set the offset a little bit lower ( to 16) and adjust the light again if needed and the noise is away.

Voitto,

Thanks for constructively confirming my findings.

I'm not quite clear on your above statement though - could you please elaborate?