Noise comparison: 35/4:2:0 vs. 180/4:2:2

[Tom Roper]

My observation was that CD and Dan had been offering outstanding support for many months before I purchased mine. It was a prime reason I felt comfortable making the purchase. Realtime support on DVInfo.net is above and beyond what is required, and clearly they have been supportive of the owners, answering questions, and with ongoing updates and free upgrades. Kudos to Dan and Mike, was never in doubt with me and I'm sure many others including Piotr.

[Piotr Wozniacki]

Originally Posted by Tom Roper

My observation was that CD and Dan had been offering outstanding support for many months before I purchased mine. It was a prime reason I felt comfortable making the purchase. Realtime support on DVInfo.net is above and beyond what is required, and clearly they have been supportive of the owners, answering questions, and with ongoing updates and free upgrades. Kudos to Dan and Mike, was never in doubt with me and I'm sure many others including Piotr.

I absolutely agree - have been in contact with Mike long before their products were launched.

As to Dan's responsiveness, I guess I've got spoiled by how great it has been - hence being a little impatient now, when it was lacking for just a couple of days :)

[Garrett Low]

Originally Posted by Piotr Wozniacki

- is it viable that CD adds some (user selectable from the menu), mild noise reduction circuitry?

This would make it possible to use all the benefits of higher bitrates (less compression artefacts), while not augmenting the level of noise from the source camera. Of course, at the cost of some detail reduction - but sometimes it could be beneficial (provided the NR can be switched on and off by the conscious user).

What do you think?

I would rather record it and do it in post using a processor with several times the power of that contained in the NF and a program that I can control the amount and parameters for noise suppression. Ads time to the post production workflow but would ultimately give much more control over the quality of the picture.

Garrett

[Piotr Wozniacki]

Doing it in post is always an option - but as you said, can be very tedious and time consuming.

Also, I have yet to find an NR tool for Vegas that I'd really be satisfied with...

[Dan Keaton]

Dear Piotr,

One problem of removing noise in the nanoFlash is that it would be permanent. Doing it in post allows one to adjust the noise reduction.

Also, I doubt if we have the extra horsepower to do this inside the Flash XDR or nanoFlash while recording at high bit-rates.

If possible, I would recommend setting up the camera to achieve a good, low-noise image, as verified by a professional HD-SDI monitor. However, I realize that this is not always possible.

[Dan Keaton]

Dear Tom,

Thanks for the kind works. We try hard to provide prompt support.

Sometimes when traveling, it is difficult to respond promptly.

[Piotr Wozniacki]

Originally Posted by Dan Keaton

Dear Piotr,

One problem of removing noise in the nanoFlash is that it would be permanent. Doing it in post allows one to adjust the noise reduction.

Also, I doubt if we have the extra horsepower to do this inside the Flash XDR or nanoFlash while recording at high bit-rates.

Fair enough, Dan.

Now that I can be sure that what I'm seeing is normal (and neither my camera's HD-SDI nor my nano is malfunctioning), the only thing I can to do is find a new, optimum combination of my EX1 settings and nanoFlash bitrate.

Thanks for addressing my doubts, and apologies for getting a little impatient before you did:)

Piotr

[Tom Roper]

Agree with Bob Grant. Would be interesting to see how the noise would fare at comparable bit rates. Of course I'm curious now how the 100mbps rate would look, since that is actually the only bit rate I have used...(cough..ahem)...I've alway thought I saw a noticeable improvement particularly with interlaced footage.

[Piotr Wozniacki]

Thant's exactly what I'm going to do, Tom - shoot exactly the same scene again, but with nanoFlash at 35 Mbps. If there is no noise increase from SxS to the nano, my camera's HD-SDI output is fine.

Since I want the results to be easily comparable, I'm waiting now for the same kind of light there was during my 180 Mbps test.

Will keep you posted.

[Gints Klimanis]

Piotr, it would be good to see 35 and 50 MBps on the Nano.

[Piotr Wozniacki]

OK, since the wheather here has changed so that it would take some time to get identical lighting - . I have browsed my older shots, and found a couple of scenes where EX1 can be compared directly to 100 Mbps Long-GoP and 220 Mbps I-frame only from nanoFlash. I will not post all of them, as they've been taken without the test in mind so they represent different scenery, lighting, and camera settings - but I can tell you that the conclusions can be summarized as follows:

1. The higher bit rate of the nanoFlash, the more detail and grain in its picture when compared to the EX1's own encoder.

2. Generally, the above tendency is more pronounced with long-GoP than with I-frame only compression

3. When comparing some perfectly lit and exposed scenes, containing negligible noise - the difference is still visible, but this time the advantages of nano's high data rate prevail: the picture contains more detail with less mosquito noise, and comparable grain level as the EX1.

To conclude: as summarized before, the "Garbage in, Compost out" (or GiCo - the slightly modified version of the GiGo rule, copyrights with Adam Stanislav :)) rule applies. Also, it's difficult to say whether the EX1 does use some NR just before compression, or its encoder has been so designed that it also smooths out the grain a little (along with fine detail, of course).

In order to take full advantage of the nanoFlash (at 100 Mbps and above) - the picture must be perfect from the camera!

I'm posting just one pair of pictures, comparing EX1 compression (left) to that of the nanoFlash at 50 Mbps. As you can see, the difference is much less pronounced than in the 180 Mbps example, which was to be expected - as with more color resolution, 50 Mbps is just about the same compression level as the 35 Mbps of the EX1.

PS. By no means I'd like this discussion to cease - to the contrary, opinions and examples from other EX/NF combo users are welcome - as well as from CD, of course !

[Piotr Wozniacki]

OK, I've done some more tests today; quite different lighting (full sunshine) - so don't worry, I'm not going to scare you with my ugly pictures :)

However, I'd like to share with you some more conclusions on the subject (most of them may be obvious for some people, but I hope they'll be of some use to those considering buying nanoFlash, and got scared by my complaining about the noise). Important clarification: in spite of bright sunshine, I set up the testing so that areas of the same wooden barn fell into deep shadow (see the screen grab), and considerable noise was generated.

So, I tested several NF bitrates again for noise - but this time, I also played with detail settings of my EX1: I tested both 50 and 180 Mbps (NF) against the EX1 with both detail off and on, the latter with crispenig at zero (default) and +35. I was hoping that at the highest bitrate, the nanoFlash would compensate for detail loss due to detail off/positive crispening, while not suffering from the (reduced) source noise...

Unfortunately, this is not happening. Even with detail off, or with detail on and crispening at 35 - at the highest long-GoP bitrate the noise is still augmented and really distracting when watching on my 50" plasma. With 50 Mbps, it's at the same level as on SxS, with color resolution enhanced and mosquito noise reduced.

So, I'll repeat: those using the EX-series cameras in run&gun (or ENG) fashion, should stick to the 50 Mbps data rate of their nanoFlashes. The bitrates of 100 and above are for those shooting in controlled environment (or those lucky ones having cameras with higher S/N).

Well - this was the bad news (sort of). The good news (for Vegas users, like myself) is that I have tried Mike Crash's Dynamic Noise Reduction filter in Vegas, and yes - it does remove most of the 180 Mbps nanofiles' excessive grain, while retaining most of the benefits (better edge definition, color resolution, and less mosquito noise). Let's hope it'll become available for the 64bit version of Vegas soon! Of course, I'm now talking about a free noise filter; those using more advanced NLEs with more robust NR, will be even better off.

To round it up: frankly, I feel quite relaxed now that I'm more aware of the problem's nature. And limiting my nanoFlash to 50 Mbps, 4:2:2 in everyday shooting is not a bad thing, after all - at least, I'll spare some CF and HDD space.

While with the live classical music recordings I do as my "serious" projects, I hope I'll have enough light and time to optimize my EX1 settings so that I can safely use 100 Mbps on the nanoFlash, as well.

[Adam Stanislav]

Originally Posted by Piotr Wozniacki

Let's hope it'll become available for the 64bit version of Vegas soon!

It this is the filter you are talking about, it is not likely to come out in 64 bits. I just downloaded its source code and it uses inline assembly language, which is 32-bit specific. So it is not a matter of simply recompiling the code for 64 bits, it would require a rewrite of some of the code.

Not impossible, of course, but we are talking about code not updated since 2004...

[Piotr Wozniacki]

Thanks Adam - do you know of a better, and 64bit, NR filer for Vegas?

Thanks,

Piotr

[Steve Kalle]

"Neat Video" works in Vegas 32 & 64 bit.