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Old July 10th, 2008, 10:08 PM   #16
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Originally Posted by Brent Kolitz View Post
My other question relates to having to use the Blackmagic A/D convertor box in the chain. Besides the obvious irritation of having to mount and cable this, does anyone know whether this will be significantly degrading the signal vs. if the JVC had the HD-SDI natively?

I guess the best comparison would be testing an HD200 & Blackmagic convertor combo against the HD250's HD-SDI output.

Otherwise, I'm wondering whether anyone here has had experience with this convertor on other cameras and can comment on how well it does.
Hi Brent-
Check out this analog vs digital comparison video using a JVC HD50 deck (720p50 HDV footage). The digital portion was captured via our nanoConnect (an HDMI to HD-SDI) while the analog capture used the component output from the deck. The video sweeps from analog to digital. You see the differences immediately.

http://convergent-design.fileburst.com/AvD.wmv
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Old July 11th, 2008, 07:10 AM   #17
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Originally Posted by Mike Schell View Post
Hi Brent-
Check out this analog vs digital comparison video using a JVC HD50 deck (720p50 HDV footage). The digital portion was captured via our nanoConnect (an HDMI to HD-SDI) while the analog capture used the component output from the deck. The video sweeps from analog to digital. You see the differences immediately.

http://convergent-design.fileburst.com/AvD.wmv
Mike,

I'm not at a computer at the moment, so I can't view the file right now. But I'm assuming that the news isn't good for the component outs.

So assuming your converter is at least as good as the Blackmagic some of us would consider using along with the nanoFlash, then I guess you're saying this venture would be an expensive waste of time?

If so, I do appreciate your honesty. And I curse JVC for only putting a digital out on the HD251, when you can get digital output on junky camcorders from Best Buy.
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Old July 11th, 2008, 07:43 AM   #18
 
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Brent...

I'm not sure you got the message. In the footage Mike refers to, which is the same footage I was referring to in my earlier post, the images captured via component->HDMI->BMD Intensity Card(19Mbps, 4:2:2, 10-bit) was quite superior to the compressed footage(4:2:0, 8-bit) captured thru the firewire port. The difference being the Intensity solution requires a computer to capture instead of a nanoflash/Flash XDR.
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Old July 11th, 2008, 08:46 AM   #19
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Brent...

I'm not sure you got the message. In the footage Mike refers to, which is the same footage I was referring to in my earlier post, the images captured via component->HDMI->BMD Intensity Card(19Mbps, 4:2:2, 10-bit) was quite superior to the compressed footage(4:2:0, 8-bit) captured thru the firewire port. The difference being the Intensity solution requires a computer to capture instead of a nanoflash/Flash XDR.
Ah -- I'm reading these posts on my Blackberry, so I guess I misunderstood. But what I'm really trying to ascertain is what degradation might we experience as a result of having to convert the analog component outs into HD-SDI in the first place, in order that we can then run that signal into the nanoFlash? Obviously the nanoFlash is intended to be used with cameras which have digital outs onboard, but JVC users of anything other than the HD250 have to stick an outboard A/D converter in the chain. So I'm wondering what will we be missing in the nanoFlash experience (other than the cost and inconvenience of another box) that users of native HD-SDI cameras will have? In other words, will we be spending a considerable amount of money on the nanoFlash, only to have its benefits limited by the fact that we have to stick that Blackmagic converter in the chain?
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Old July 11th, 2008, 09:03 AM   #20
 
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IMHO, if you use a high quality converter, at least 10-bit, like either the BMD or C-D nanoconnect, the image will be noticeably better. That's exactly what the footage Mike Schell referred you to, will show, as it was recorded with an HD100. The image should be comparable to the HD250 image out. I think component analog signals degrade with distance, so, you want to connect the converter box as close to the camera ports as possible.
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Old July 11th, 2008, 10:00 AM   #21
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Originally Posted by Brent Kolitz View Post
Ah -- I'm reading these posts on my Blackberry, so I guess I misunderstood. But what I'm really trying to ascertain is what degradation might we experience as a result of having to convert the analog component outs into HD-SDI in the first place, in order that we can then run that signal into the nanoFlash? Obviously the nanoFlash is intended to be used with cameras which have digital outs onboard, but JVC users of anything other than the HD250 have to stick an outboard A/D converter in the chain. So I'm wondering what will we be missing in the nanoFlash experience (other than the cost and inconvenience of another box) that users of native HD-SDI cameras will have? In other words, will we be spending a considerable amount of money on the nanoFlash, only to have its benefits limited by the fact that we have to stick that Blackmagic converter in the chain?
I apoologize, but I did not fully explain the comparison video, as this would clearly answer your question. The JVC comparison clip, available at: http://convergent-design.fileburst.com/AvD.wmv sweeps between an analog and digital capture into an NLE system. You can clearly see the improved quality via the digital capture.

The video was originally shot on a JVC 200 series camera in 720p. The HDV tape was then transferred to a JVC HD50 deck. The video was captured into an NLE via two separate paths:

1) HDMI (from the HD50 deck) -> nanoConnect -> HD-SDI -> NLE
2) Analog Component (from the HD50 deck) -> NLE capture card (I think it was a Blackmagic card).

The two captures were placed on two tracks in the timeline. The final video was created by sweeping back and forth between the two clips.
So, watching the video you can clearly see the effects of the analog capture vs the digital capture.

However, the overall quality of the video you will see using the analog outputs from the JVC camera -> HD-SDI converter -> nanoFlash, will of course, be much higher. The original video was heavily compressed by the HDV CODEC in JVC camera, a live feed from the camera will not have this compression and will be in full 4:2:2 color space.

So, yes there is some loss going the analog conversion route. But, in my experience the loss due to the HDV compression and 4:2:2 -> 4:2:0 conversion, is much greater.
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Old July 11th, 2008, 10:41 AM   #22
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Thanks for that detailed explanation, Mike -- I'll be sure to check out those samples.

I'm not surprised to hear that using the BMD converter/nanoFlash combo would be a step up from HDV.

I guess what I'm questioning is whether the expense of this is justified by the gain (though everyone will have their own definition of this).
If the JVC HD100/110/200 had SDI out, then I might jump at the nanoFlash. I guess my concern is how much image quality would I be losing by having to go through that initial A/D conversion step? If the nanoFlash were 1/4 of the price, then I probably wouldn't worry about it. But the whole combo is a big expense, and I worry that I'd feel maybe the money should have been put toward a Scarlet (or whatever).

It's the JVC's lack of HD-SDI that's really making this decision complicated for me.
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Old July 11th, 2008, 10:46 AM   #23
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I assume you get the same from HDMI as you do from HDSDI, once you've got all the right connections made. Even the HDSDI has to go through A/D conversion doesn't it, as the CCD is analogue, so the HDMI should just be the same process and once it's coming out of the HDMI plug and going into any of the Convegent Designs units it's digital all the way. Assuming that's the case then jumping up from 19 to 100 mb/sec or to 160 mb/sec I-Frame has got to be huge!
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Old July 11th, 2008, 10:48 AM   #24
 
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kinda my thinking, too, Steve. I think it's analog RGB coming off of the sensor block. A-D converters, in the camera, digitize to YUV for storage and compression. Question is, "does the component signal come before or after the digitizing process?" If it comes after, then there are at least 2 conversions before the component port gets the signal.
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Old July 11th, 2008, 11:16 AM   #25
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kinda my thinking, too, Steve. I think it's analog RGB coming off of the sensor block. A-D converters, in the camera, digitize to YUV for storage and compression. Question is, "does the component signal come before or after the digitizing process?" If it comes after, then there are at least 2 conversions before the component port gets the signal.
Every camera requires an A/D to convert the CMOS/CCD analog sensor voltage to a digital value. After that analog conversion, all the subsequent processing is made in the digital domain. If the output is HD-SDI or HDMI, then there is no analog conversion losses on output (the HDMI signal is essentially identical to HD-SDI).

If however, you go the component analog output route, then you have an D/A conversion (inside the camera) followed by a A/D conversion inside the NLE capture card (or the external converter).

Time permitting, we will test these two conversion paths using our Flash XDR / nanoFlash set at 50/100 Mbps. I feel confident you'll see substantial gains from the higher bit-rate, but it is very difficult to quantify the various effects of analog conversion followed by compression.
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Old July 11th, 2008, 11:25 AM   #26
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Originally Posted by Mike Schell View Post
...The JVC comparison clip, available at: http://convergent-design.fileburst.com/AvD.wmv sweeps between an analog and digital capture into an NLE system. You can clearly see the improved quality via the digital capture....
That's a very effective comparison. It's almost unbelievable to get the sharpness difference between an already compressed video signal.

I'd like to see you repeat the test when the NANOflash is ready... going through a BlackMagic (or equivalent) analog component to HD-SDI conversion.

I can see alot of JVC owners willing to step away from tape (decks, dropouts) and the dreaded be careful not to blow the firewire port.

A follow up question, Which editing programs are the friendliest to this recording format? Will some users need to convert the files to a different format for editing? Has any testing been done with color correction in this native format?
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Old July 11th, 2008, 12:20 PM   #27
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That's a very effective comparison. It's almost unbelievable to get the sharpness difference between an already compressed video signal.

I'd like to see you repeat the test when the NANOflash is ready... going through a BlackMagic (or equivalent) analog component to HD-SDI conversion.

I can see alot of JVC owners willing to step away from tape (decks, dropouts) and the dreaded be careful not to blow the firewire port.

A follow up question, Which editing programs are the friendliest to this recording format? Will some users need to convert the files to a different format for editing? Has any testing been done with color correction in this native format?
Hi Jim-
Final Cut Pro has the best support now, Avid is not too far behind. We will be sending out test files to all the NLE manufacturers in the near future for compatibility tests.

Some users may need to convert the files. Worse come to worse, you can ingest via the HD-SDI output from the Flash XDR / nanoFlash. But, I doubt many users will have to go this route.

Here's our list of the Ten Top Reasons to Go (Solid State) Tapeless

1) No Digitization/Capture
a. No need to digitize (convert from analog to digital) your analog video tape or to perform a laborious 1X capture of your material (no more batch captures).
b. Edit instantly from the solid-state media (card).
c. Transfers to other media (hard-drives) are performed at speeds much greater than real-time (typically 3x to 6x)
d. Random access to any frame in any clip, no need to fast-forward / rewind tape.
e. No drop-outs or time-code breaks!

2) No Deck Required
a. Significant initial (purchase) cost savings as well as long-term maintenance (head/drum replacement) cost savings.
b. Solid-state memory card readers are very low in cost (US $60), very reliable, and do not require maintenance.

3) Lower weight, size, noise, vibration and power
a. Much lower weight (3 lbs vs. 5 ~ 50 lbs)
b. Much smaller (1/4 to 1/10 the overall volume)
c. Zero noise (no fans)
d. No vibration (no moving parts inside)
e. Very low power consumption (12W vs 40 ~ 100W)

4) Performance increases as size decreases
a. Hard-drive performance decreases with smaller physical size drives (due to slower rotational speeds). For example, 1.8” drives don’t have insufficient I/O performance for data-rates much above 35 to 40 Mbps. Hard drive performance also drops off as the volume reaches capacity.
b. Solid-state performance, on the other hand, improves with decreasing chip size and the performance is uniform across the entire volume.
c. Tape storage capacity is directly related to the physical size of the tape for a given technology. If you want more capacity on your tape, you have to buy a physically larger cartridge. Solid State media capacity continues to double every 12-18 months, while the physical size of the media remains constant.

5) Superior Reliability
a. No mechanical parts to fail / tape to jam.
b. Much better reliability in harsh conditions.
c. Will work in extreme conditions, where a tape-drive will likely fail, such as in very high humidity.

6) Instant Replay
a. Instant review of just recorded footage can revolutionize shooting on the set. Catching problems while on the set, before striking the set, can be priceless. The director can ensure that he or she has the desired footage without any worries about rewinding tape or time-code breaks.
b. Even during a playback session, recording starts immediately, as appropriate, without a delay to reposition the tape.
c. The system is ready to record instantly, even during a playback session. All recording is done after the last recorded file, no need to position the tape. No danger of recording over valuable footage, one of the main reasons that rewinding and playback of tape is discouraged on the set.

7) Redundant Recording
a. Identical video can be written to multiple cards simultaneously, an impossible option with tape and difficult to achieve with portable hard-drives.
b. In the unlikely case of a media error, the other original will be unaffected.
c. Individual masters can be transported via independent means for safety.
d. One card can be handed-off to an editor, while a second card is given to the producer/director for review on a PC/MAC.

8) MetaData Support
a. The ability to document and record extra data about each take is very useful in post and while reviewing footage.
b. User specified metadata can be very useful for a production (director, cameraman, take, event, location, camera number, etc.)
c. Custom notes about a take can be recorded with the audio and video.
d. Takes can be easily marked as Bad, Good, or “Best”.

9) Wider Operating Environment
a. Solid-state media works at extreme hot and cold temperatures.
b. Hard disk drives cannot be used at high altitudes or in very cold conditions.
c. Few problems from condensation when going from one environment to another.
d. Operates in high G-Force conditions (airplanes, helicopters, race-cars), where tape or hard-drives would fail.

10) Ever decreasing costs
a. Tape costs have bottomed out and show no signs of further cost reductions.
b. Solid state media has a significant track record of providing higher capacity and lower cost each year.
c. Solid state media is already used in many professional environments (such as digital cameras).
d. Our industry can benefit from the widespread use, wide availability, high volume, and low cost of solid-state media (such as CompactFlash).
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Old July 12th, 2008, 10:34 AM   #28
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I watched the clip and I have to say, the HDV portion looks pretty rough to me.

I also agree a test using a 250 model with a Nano recording SDI out, a Nano recording component out (with converter) and recording to tape at the same time would be very useful.

This would show all options and we could see how much the Nano is affecting image quality.
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Old July 12th, 2008, 10:58 AM   #29
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I watched the clip and I have to say, the HDV portion looks pretty rough to me...
...

That's why I would like to see it re-tested. Both clips are HDV compressed. For some reason they didn't do a comparison to regular HDV captured in it's native format. The extra analog conversion is NOT going to make HDV look better. It gives the look of having the backfocus slightly out of focus and the blacks are a little brighter.

We know that the JVC 250 is best option for the NanoFLASH...but, I would like to see a comparison w/ a 100 series (since there are more 100's out there) converted to HD-SDI and then compared to what the camera gets off tape in it's native HDV format.

The current test does make you wish that JVC had a HDMI out on the camera...if in fact, the current component analog outs go through a D/A conversion.
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Old July 12th, 2008, 11:58 AM   #30
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Dear Jim,

Personnally, I feel that the only way to tell if the component outputs of any camera, through a component to HD-SDI converter XDR will be good enough, will be to test it.

Camera manufacturers use various grades of Digital to Analog converters in their camera's circuits. These D to A converters help determine the quality of the component outputs.

The same applies to component to HD-SDI converters. Not all are created equal. This could be a case where you usually get what you pay for. In order to achieve great quality, great components and careful attention to design details is essential.

It seems apparent to me, that for certain cameras, the component outputs were intended for monitoring only, and the tape drive was meant for recording.

As such, it was up to the manufacturer to decide on the quality of the component output circuits. I do not think much thought was given to the concept of recording via the component outputs, but I could be wrong.

In any case, the component outputs are available on many cameras, and they probably are good enough for you to consider recording from these outputs.

If you feel that your camera's component outputs are good enough, then converting the outputs to HD-SDI and then recording via a nanoFlash or Flash XDR may work out fine. Time will tell, and we do intend on testing this as soon as we get time.

Of course, there is an inherent advantage of recording from the component outputs as they have not gone through the compression process.

In any case, the component outputs should be superior to the Firewire (IEEE 1394) output in terms of quality.

One side advantage is that no one ever hears about a component output being damaged, but blown Firewire ports are reported occasionally. If one has a blown Firewire port, the component outputs are usually still available and working.

I have access to a JVC HD100u (with a blown Firewire port). I hope to borrow a component to HD-SDI converter and then test it with my Flash XDR (shortly after I get mine).

Please note that the recording quality of the nanoFlash and the Flash XDR will be the same, for the same compression rate. So testing a camera's component outputs with a Flash XDR will indicate how well it will work with the upcoming nanoFlash.

Last year, on the set of "Deadland", we used a HVX200 with a Red Rock 35 mm adapter. We used an AJA component to HD-SDI converter and it worked great. We monitored our shots with a Sony LMD-2450 monitor and the image was outstanding.

This year, on the set of "Perfect Disguise", we used a JVC HD100u, with a Red Rock, and we used the component outputs to the Sony LMD-2450 monitor. During the shooting of this movie, the Firewire port was blown. We were recording via Firewire to a Firestore.

I can report that we had some trouble with the Firewire cable falling out at times. But we never had trouble with the component cables coming loose.
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