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-   -   Noise comparison: 35/4:2:0 vs. 180/4:2:2 (https://www.dvinfo.net/forum/convergent-design-odyssey/479723-noise-comparison-35-4-2-0-vs-180-4-2-2-a.html)

Gints Klimanis August 11th, 2010 05:11 PM

Quote:

Originally Posted by Mark Job (Post 1558187)
Not necessary. Try Raid 0. Problem solved.

How would the XDR or Nano record these? My Nano only has CF slots for recording, and I don't see the appropriate connectors for external storage in the XDR pictures.

Dan Keaton August 11th, 2010 05:42 PM

Dear Mark,

We like to be very open with our communications.

However, our upper recording bit-rate, what is actually possible, is something that we prefer not to divulge for competitive reasons.

Mark Job August 11th, 2010 07:01 PM

No Disrespect Intended
 
Quote:

Originally Posted by Dan Keaton (Post 1558209)
Dear Mark,

We like to be very open with our communications.

However, our upper recording bit-rate, what is actually possible, is something that we prefer not to divulge for competitive reasons.

Dear Dan:
I was never fishing for private company internal information of this nature about CD's products, I was only requesting a higher data rate option for I-Frame recording for special high end digital cinema or special effects shooting. I don't understand how requesting 300 Mbps or 320 Mbps could trespass on this. Sorry.

Mark Job August 11th, 2010 07:15 PM

External Storage Not Needed
 
Quote:

Originally Posted by Gints Klimanis (Post 1558199)
How would the XDR or Nano record these? My Nano only has CF slots for recording, and I don't see the appropriate connectors for external storage in the XDR pictures.

Hey Gints: No, no - You don't require any external storage for this feat. I'm not sure the Nano Flash can even do uncompressed, but I think the old XDR is built slightly differently internally (But I really do NOT know ???) You Raid 0 all 4 cards in an XDR or 2 cards in a Nano (If possible- I do NOT know). You use those newer 64 GB CF Cards which can do 60 and 90 MB per second playback from Sandisk (Forget their name - sorry), and you record in a striped configuration of 2 or 4 cards (Should be end user choice as option in menu). You shoot, but do NOT remove the striped CF card media from the Nano or XDR and you either....

1. Playout in realtime via HD-SDI from Nano or XDR.
2. Transfer files from XDR/Nano to computer via built in FireWire (Slow but do-able - Faster CF card media will transfer in Raid 0 config faster anyway)

You bypass the internal encoding engine with this option, thus you are inherently now up to 10 bits from 8.
* You could even stripe for *Compressed MPEG 2 recording ! Why not ? Then you can really boost your I-Frame encoding data rate

Gints Klimanis August 11th, 2010 08:07 PM

Sandisk Extreme does 60 MBytes/second write while Sandisk Extreme Pro does 90 MBytes/second . Now that I'm moving to 200 Mbps I-frame only, my wallet will become friends with the only fast 64 GB card Sandisk makes. I bought two spanking new 32 GByte Sandisk extreme cards eight months ago. How many times have I "re-promised" that I will never buy another $400+ flash card again ? Hey wait, there's no swearing at work.

Gints Klimanis August 11th, 2010 09:12 PM

Quote:

Originally Posted by Mark Job (Post 1558230)
1. Playout in realtime via HD-SDI from Nano or XDR.
2. Transfer files from XDR/Nano to computer via built in FireWire (Slow but do-able - Faster CF card media will transfer in Raid 0 config faster anyway)

CD would provide utility to interleave the files after specifying two directories from the CF cards that have been copied to your computer.

Mark Job August 11th, 2010 09:15 PM

Those Pricey But Excellent Sandisk Cards
 
Hey Gints:
I have a hodge - podge of those Sandisk cards myself. I have 2 x 32 GB Sandisk Extreme III's, 1 x 16 GB Sandisk Extreme IV, and one 8 GB Sandisk Extreme III. I shove them all into my XDR and I can even record at 280 Mbps I-Frame across all 4 cards. The only eccentricity is that the fastest card (16 GB Extreme IV @ 45 MB per sec) has to be in the first slot, or else XDR will automatically down set everything to 220 Mbps.

Piotr Wozniacki August 12th, 2010 05:46 AM

It's good some humor, and relaxed comments, have been introduced to this somewhat delicate (and thus, tense) thread :)

But back to the topic: after Alister's comments, I don't feel isolated any more in my assessment of things, so I will tell you this (I wonder how many of you guys will agree):

- the EX1 is indeed inherently noisy; in fact (contrary to the generally adopted belief) this inherent noise is much more dependent on the scene nature than the level of lighting - in fact, many scenes shoot with gain at -3dB suffer from the shimmering more than some low-light scenes, shoot at +3dB, or even higher gain!

- unfortunately, nanoFlash is not the holy grail for curing this; at low bitrates (and I-Fo especially) it can be a complete mess, while at the highest bitrates (and in L-GoP especially) it augments this noise. I believe it's fair to make all the current and potential users aware of that.

Also, while I am sceptical about the nanoFlash potential to record with bitrates significantly higher than it's capable of currently (it's just not been designed to do so), I'm very much for the idea of Convergent Design considering to use the Sony encoder chip in the "constant quality, automatically variable max bitrate" mode (if at all possible).

What do you say, Dan and Mike?

I'd also suggest removing the options for I-Fo below 180 Mbps from the menu of available recording formats.

Dan Keaton August 12th, 2010 06:25 AM

Dear Friends,

We love to be responsive to customer suggestions and implement them if possible.

We may be able to implement VBR (Variable Bit-Rate). However, we have to be cautious, in that the files have to work in the various NLE's.

(It would be best if the VBR files work in every NLE. If not, then we would be creating a "trap" in which a user could select an option, but then his or her files would not work in their NLE.)

We are trying to keep our menu options limited, so that the nanoFlash is not complicated to use or intimidating to first time users.

(But, this is not an issue, if all NLE's support VBR files).

We could use some information.

For example, if we just change our files to VBR from CBR (Constant Bit Rate), would these files work in your NLE's?

Please let us know which type of files will work in VBR mode.

Piotr Wozniacki August 12th, 2010 06:36 AM

Dear Dan,

Some CBR formats must be left for sure (e.g. the L-GoP, XDCAM HD 50/422), to ensure the widest NLE compatibility with the well established formats (there are sure more of them).

As to other formats (especially I-Fo), my knowledge is not deep enough - let's wait for our gurus' comments.

Thanks anyway, for your instant response!

Piotr

Mark Job August 12th, 2010 07:36 AM

VBR Encoding does not affect NLE usage
 
Quote:

Originally Posted by Dan Keaton (Post 1558382)
Dear Friends,

We love to be responsive to customer suggestions and implement them if possible.

We may be able to implement VBR (Variable Bit-Rate). However, we have to be cautious, in that the files have to work in the various NLE's.

(It would be best if the VBR files work in every NLE. If not, then we would be creating a "trap" in which a user could select an option, but then his or her files would not work in their NLE.)

....Hi Dan: I don't understand your premise here. VBR only affects a file in the way it is encoded, but has nothing to do with the finally completed file being manipulated in any NLE.

Quote:

Originally Posted by Dan Keaton (Post 1558382)
are trying to keep our menu options limited, so that the nanoFlash is not complicated to use or intimidating to first time users.

...How would this complicate the menu system ?

Quote:

Originally Posted by Dan Keaton (Post 1558382)
But, this is not an issue, if all NLE's support VBR files).

We could use some information.

For example, if we just change our files to VBR from CBR (Constant Bit Rate), would these files work in your NLE's?

Please let us know which type of files will work in VBR mode.

...Dan, I think this needs to be additive and not one OR the other.

Dan Keaton August 12th, 2010 10:49 AM

Dear Mark,

For Final Cut Pro, our files are identified as Sony XDCam 4:2:2 50 Mbps CBR, for our bit-rates 50 Mbps or higher.

I wonder if we encode the files as VBR and then indicate that they are VBR, whether the NLE's will recognize the files?

Or, whether if we encode in VBR, and specify that they are CBR, if the NLE's willl work with the files?

In response to your post: If we add another menu item, and there is a chance that it could be set wrong, then we are complicating things by adding the new menu item.

We will be discussing this.

Gints Klimanis August 12th, 2010 12:03 PM

Dan, I'm willing to test the VBR files for the Final Cut Pro, Sony Vegas 9 and provide comments with convenience software such as VLC Media Player, Windows Media Player, Western Digital TV and Sony PS3.

After stepping through my own and Piotr's footage, I'm biased against using 140+ Mbps LongGOP due to the quality drop from the I-frame, and the noise from that variation. There is a visible increase in quality almost every 6 frames when viewed on my Apple Cinema 23" display.

CD is creative enough to provide a default for Quality variation parameter. A single parameter could control both B-frame and P-frame "spoilage".

Gints Klimanis August 12th, 2010 12:13 PM

Quote:

Originally Posted by Piotr Wozniacki (Post 1558369)
- the EX1 is indeed inherently noisy; in fact (contrary to the generally adopted belief) this inherent noise is much more dependent on the scene nature than the level of lighting - in fact, many scenes shoot with gain at -3dB suffer from the shimmering more than some low-light scenes, shoot at +3dB, or even higher gain!

I'm not sure if you're implying that the Sony noise level is less at Gain=-3dB, but there are a number of posts on the Sony XDCAM group that -3dB does not provide a higher SNR - only a signal attenuated by 3 dB.

Adam Stanislav August 12th, 2010 12:48 PM

Personally, I always use 0 dB gain. That is what comes out of the hardware, and I do not feel like messing with it. At least not until post.


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