A while back, I tried using the HD10U for greenscreen work and yeah, the whole image sensor seems riddled with red noise so the green screens looked a little grey and the macroblocking of MPEG-2 didn't help. However, thanks to Leo, he pointed out that the HD1/10 uses CMYW as the filter array on the CCD.

I did some research on that type of array and started looking at algorithms for color conversion (CMY -> RGB -> YUV). CMY has a better spectral response according to all the charts I've seen, but the fact there are multiple transforms to go through to end up with YUV might be causing some issues. I also wonder if it's true that the HD10U uses BT601 colorspace vs. the HD standard of BT709.

Sony makes their own CCDs and CMOSs. JVC has used AltaSens in the past, so chances are JVC will continue to use them since R&D efforts have already been established. As far as an HD1 replacement, I haven't heard anything; the only thing coming out of JVC that gets any mention is the 100U.

Perhaps JVC can't compete with Sony in the consumer market now that HDV is somewhat a toddler and out of infancy. JVC had HDV all wrapped up until the FX1 hit. They've always been kind of a bleeding edge/maverick of a company which is why so many people don't think too highly of them.

I'm a little wary of enabling gain on the HD10U for one reason: MPEG compression compresses better with no noise. If you crank up the gain, chances are the B-frames are gonna get screwed (misprediction due to the movement of noise). But it'll be nice to know at least we can control the gain once we find the bit. I think JVC left out gain control so it doesn't screw up their short-GOP compression (maybe gain breaks it).

I have more on my plate at the moment that I can cope with - e.g. I have found how to separate EE and sharpness. And I think I have found gain and knee control settings too. I need a controlled way to measure things that I am altering.

Colour conversion is a tricky beast. There is a good primer on WhGrCyYe matrix used in HD10 here: http://images.videosystems.com/files...sexpertise.pdf

You are right, Xander, there are so many stages in getting YUV that it is difficult to pick the optimal setting for all the stages. At the moment I have some great low light results but at the expense of colour saturation and separation.

Fundamental difference between 3 and 1 CCD cameras is that in 1CCD camera all four (or three) pixel colours are digitised by the same ADC and it is impossible to control ADC parameters (shift and gain) independently (i.e. on the fly). In 3 CCD camera you can pre-adjust the ADCs separately (gain is the first stage of ADC conversion process and is applied to analogue signal before the signal hits the ADC itself, even though it is done inside the ADC chip), therefore excess in one part of the spectrum , e.g. Red for flood lights will still allow Blue CCD chip ADC to use independent higher gain to pick up blue details.

What happens in 1CCD and especially with WGCY matrix, you have only one ADC and only one chance to set the gain to squeeze CCD output into ADC dynamic range. Naturally it is set to avoid overexposure. But because White pixels on WGCY matrix have nearly twice the sensitivity of Cyan, the ADC produces readings for Cyan pixels at only half of its dynamic range and it has later to be doubled in software. Thus noise is doubled too. Now if you consider that Cyan is opposite to Red and it is Cyan pixels that play major role in Red colours separation from the rest (Red = White - Cyan), this might explain bad handling and excessive noise in Reds in JVC cams.

Does it make any sense?

Perfectly Leo. Xander thanks as well. Gain like this is not a total loss, in guerrilla Documentary style, some sort of image in a dark place would be better than nothing.

Has anybody every broken one of these apart and applied a SLR lens through a condenser to get a brighter image, like some Canon Lens adaptors do for the XL1s?

"I have found how to separate EE and sharpness. And I think I have found gain and knee control settings too."
Wow, that is fantastic.

On a downside, untill someone can produce the needed cable for a decent cost, or provide a DIY for dummies, this experimentation may end at Leo. It has been said JVC does not sell the cable, so we need a solution for the masses (well the brave few.)

**Note**
I have reviewed the whole thread and realize it was stated that the plans at http://pagina.vizzavi.pt/~ng93827a/JVC/
are said to work with the HD JVC's. Good news. Does anyone want to add any tip'n'tricks to the info provided at this page?

Wayne - regarding removing the current lens and attaching a 35mm lens to the HD10, a friend of mine is working on such a thing right now. However, I think he's looking to attach a 2/3" lens since the multiplication factor will only be 2x instead of 7x (1/2" lens would be 1.3x, but I don't have one of those to give him).

Ken - the PD1/HD1/HD10's cable assembly from JVC costs $275. If there's enough people wanting to get one, I can perhaps place a quantity order and reduce the cost? I built the cable shown on the website noted above, but trust me, it's not worth the hassle (I'm a novice solderer and had issues). $275 is reasonable. :)

Xander, the chip in PD1/HD1/HD10 is ICX426AU which smells to me like a Sony part. They also have a gap in their lineup with that number so I assume it was a custom order.

So you have a cable!? I desparately need a dump of HD1/HD10 EEPROM to move any further. I was even considering buying one for the purpose of downloading it!

Xander,

We got two very similar threads going..

$275 is reasonable. My Paypal is ready to go.

I'm willing to provide the dump as fast as this transaction will go and that my GR HD1 wont blow.

Ok one more question..is the JLIP connected behind that little secret square door next to the iLink port?

Leo, I'd be still willing to donate towards your efforts on finding all the adjustments.

Allen

Here is a picture of my connector: http://www.lbodnar.dsl.pipex.com/video/plug.jpg
I found the plug that is the right pitch but slightly larger, so I had to file it a bit then epoxied it to breadboard and soldered three tiny wires. It also has a MAX232 level converter at the other end of the cable.

I can make a few commercial quality ones if I find the right connector that would be the right size. However my current thought is about an inch-sized self-contained unit with Microchip's PIC controller inside, couple of push-buttons and maybe a LED, that can be plugged in the camera in the field for quick settings changes.

Yes, "the thingy" is behind that little secret door!

Tell him to use a condenser instead, that way you should get no magnification factor with the right condenser, and some stops more in light (with right lens). That may get him to 9 Lux with a very fast lens, maybe a good SLR could get down to 5 lux etc. There is a Canon adaptor that does this so you can use their 35mm SLR lens on the Canon in this way. Search for my first post on DVinfo (on increasing camera image brightness) and go down towards the end of the thread there should be a link to another thread that talks about that adaptor. There might be an aperture limit to how far you can open up to, where the microlens array distorts the image because the angle of light is too great.


Thanks

Wayne.

JLIP JIG for PD1/HD1/HD10
 

To all who are interested:

I can get a group discount for the official JVC service cable if I can order 5 or more. THe cost goes from $275 to $250. Email me off list is you want to order one.

Personaly I would rather bundle my $ into a group project like Leo's. JVC has been a corporate bit#h as far as even acknowledging or giving any respect to us early adopters. HD100 $ is all they see now, after advertising the HD10 as the filmakers choice for the last two years. Besides the JVC cable will still leave us at square one, where as Leo is proposing something that can really make the cam versatile without supporting a corp that is dropping their pants in our direction.
I may sound bitter, but truth be told I have emailed JVC corp more than once asking about reported firmware upgrades or some such that gives newer cams of the same model # improved performance. I have brought up that even people who have had repairs done have reported increased performance upon return. Never a reply. Ever.
I will personally do what ever I can to evolve a cam that I think is grounbdbreaking and under rated. I only wish JVC felt the same.
I have a strong feeling JVC is planning to reintroduce this same cam as a new generation with the improvements we lack. HD11 for the masses?

Ken

The staff may only know what head office tells them. I emailed and called JVC about the Altasens product on their website, and they knew nothing.

I would suggest it be best to see the local professional distributor with a service centre about it, and paying them to do it, maybe as part of a service.

Wayne

Good idea. I have had local JVC work done befor, I'm just not sure of the " wink factor" if you get what I mean. I know very well how things are supposed to be done, but I think it is time for the consumer to be treated as at least somewhat important. JVC as a Corp have been complete jerk-#@%'s as to supporting a group of people who by buying their product's which gave them a vote of confidence in the most primative days of HDV. This should not be overlooked, but it has. We built HDV, and JVC does not give a damn. Mr. Freed? It looks more and more like our confidace in JVC has been out of loyalty rather than education. A simple backing of these not so cheap cams would put JVC back into the respectability zone, but that seems like wishfull thinking from a company who forgets you as soon as your purchase is made.
There has been repeated evidance of firmware and hardware updates of the same model #'s but no akknowledgements as to any advancements to the very same product lines, Why? Do we not believe JVC could not come up with a successor to the HD10? Really? They were just so stuck on how to improve it ?
Or is it an example of using the early adopters to absorb the costs of putting out a new cam and pretending it is new?
My only point? The HD10 is ground breaking, and the company behind it sucks like no other. What a conundrum.

PS - Sorry for the rant, but come'on. Wtf!

The introduction of the HD100 might work in our favour - they might not be as protective over the triplet cams.

Let's just get HD1/0 dump to Leo somehow.

Looks like Xander is the best person to provide the HD1 dump to Leo.

I am also on a watch for a well-beaten or broken HD1 that I can experiment with. Let me know if you spot one!

To keep you updated:

Tonight have unlocked the menu entries for colour bars and audio rec level indicator.

Sweet!!! damn I wish I still had an HD...

man, just filmed my wife's birthday with my newborns..indoors. in manual with nothing else set..the picture sure came out muddy.

Granted it was lit by the chandeliar..but it was bright..everything was mud.

Any new infos about the PD1/HD1?

Marco

yeah, Leo, it's been ages - have you managed to unlock anything else since unlocking the menu entries for colour bars and audio rec level indicator?

We're very excited.

I'm very curious if there is a way to get 1280x720 out of the PD1 via firewire just like the HD1 does.

Marco

Hi there! I am back...

It's been awhile but I am looking at GR-PD1/HD1 again. I believe there could be something done to make them better!

I have stopped the research after I was not able to get access to HD1/HD10 or their memory dump but now I had to put some logical end to it and have ordered a new HD10.

For the last year I was shooting with EE completely turned off and I like the effect so much.

My biggest problem is that the camera that I have (PD1) was bought second-hand and I believe was not colour-adjusted properly - colour saturation changes with the luma. I.e. when exposure level drops, colours seems to become more vibrant. Exactly like if you had linearity problems in luma vs chroma channel on an analogue equipment.
This, obviously, makes chroma noise more pronounced in the dark areas...

Hi Leo

Welcome back.

Could be the extra poor low light sensitivity of the JVC sensor. With the GR-DV3000, lower light produced unbalanced colour (unless you use the presets) but mostly grey, that seems like the test frames of the HD10 too. On cheaper cameras there is a trick to increase gain and saturation in low light. The way the JVC sensor works makes red noise worse as well.

I have been putting out feelers for a low priced secondhand JVC PD1/HD1/10, but no response.


Anyway, have you seen my thread here on JVC mod ideas:

http://www.dvinfo.net/conf/showthread.php?t=64636


Another camera that could produce better results then the JVC with modification, is the Sanyo HD1 for $799, and it is probably not even the best one coming.

Wayne,

Email me, hmcknight@mac.com, about an HD10. I may be able to sell it (it's a lease that I'm paying off this month), depending on several factors with the leasing company.

heath

There's a HD1 on eBay for $412, bidding. Seller still has box, juding by the photo they posted, not that this means anything of course..

Thanks guys, I had pretty much given up on that idea (my post in the classifieds forums didn't attract anything) and the H264 cameras are nearly here, the Samsung in August, the AVCHD, I don't know. So I am only looking as a cheap fill in camera. I have even been thinking of that $799 Sanyo HD1 (posting about a possible solution to the macro orientation bug over there).

So I will try the email now, Keith.

Graham, thanks, $412 would be great, but I am in need of sleep, so I'll have to check it latter. I did look at ebay previously, but the cameras went for a lot more than that by the time the auction finished.

Hey Leo, good to hear your back in action. In your soon to be extended tinkering if you ever come accross a variable for any of the presets, that would be great. For example the "Sports" preset sets the shutter to 1/250th and up. If this default could be changed to the far more usefull 1/60th and up, it would become thew single most usefull feature on the cam. Couple this with EE reduction and these used HD1's would become an amazing bargin.
Keep in touch and good luck.

Don't forget low light gain, and manual functions (especially locking the shutter down to 30/60fps).

Wayne, Ken, I will definitely try to find anything of interest. I have here default and AGC low light limits but, obviously, this needs controlled experiments. I also have few sound parameters but I haven't looked at them closely enough. Looks like they are low and high-pass filters, gain and audio AGC timing.

I agree that tweaking one of the [unused] presets is an easy way to get some manual control over exposure. I will look at it more closely.

Thanks for everybody.

As I understand, there is virtually no gain in HD mode (that famous 36 horror lux rating, as deadly as no 25fps support). This is due to noise problems with the design, which I always thought was not as good as what was needed. But, for run and gun, footage with noise is better then no footage at all.

The sensor has likely been greatly improved since it was released, so this might prove to be better then expected on some cameras.

Negative gain to extend exposure latitude is also another trick.

As long as you can controll light with variable polarizer's (ND's) or ND filters themselves, the cam always reverts to 1/30th in HD mode. At times you can finesse it to 1/60th and maintain an exposure lock, but it is tricky. If I knew I could just flick on the sports "preset" at get a 1/60th lock and then was free to lock exposure, it would save so much time and effort. One would still need to apply filters if needed to prevent it from climbing higher then 1/60th (or the old 1/250th) if there is too much light comming in. But a least you know it would never drop down to 1/30th.

I personally do not think a gain boost is of much use. In low light the cam is far too noisy for it to be much use. Lowering the shutter and leaving it in auto exposure as well as shooting in the SD HDV mode are far better options. (The SD mode looks almost every bit as good as the HD mode except for medium to long shots where you want background detail. It intercuts seemlessly with HD footage)

True 24fps/25fps on this camera.
 

Yes, it is totally possible to shoot 25p or even 24p, on this camera.

I was thinking of an old idea I had for fitting 25p in a 30p stream, for a universal camera footage. I contemplated on how using this technique you could do 25p on this camera, but using a external shutter working at 50th of a second, moving the timing around (smooth, but slight variations) so that 25 frames would fall in 25 of the thirty frames (I know you guys are interested in 24fps, but it applies the same). As there is nothing to record in the other five frames, they get marked as blanks and hopefully that extra bandwidth is freed up for the other 25 frames.

This works because a 1/50th a second shutter can be moved around inside a 1/30th a second frame. We move the frame so it gradually goes up against the hard edge of the beginning of the frame to be skipped, and frame after at the hard edge of the previous frame. This reduces the jump across the skipped frame. The camera shutter has to be 30th a second so the sensor is nearly always on, which might increase dark current noise. It then occurred to me, hey if it is always on then we can simply dump the 1/50th shutter image the sensor at anytime, treating the camera frames as a continuous storage device. Some 1/25th of a second images will be split across two 1/30th a second frames, but this can be joined together by software and the blanks removed. There might be a problem of a lag in between the 1/30th second frames (not true 1/30th a second) or variation in brightness because of readout, but adjusting the external shutter slightly to avoid this should eliminate it. the is adjustment, if at all required, would probably be much less then then the adjustment needed in the first and you might be hard pressed to notice it even if you were looking for it. With the first scheme, you would probably notice it, if you were looking for it, but even fi you did it would be so subtle as not to concern you anyway.

The external shutter always does 1/50th/s stopping variation in light response in the sensor as the frame period changes. You might be able to do this electrically by hacking the camera, but shutters for movie cameras start at over $100. If you can replace the lens with an SLR lens through a condenser, which would give you a number more stops lowlight, you could add the shutter there and a variable ND to reduce blowout from the extra brightness of the SLR lens.

Now, about that gain, yes please, with an SLR lens, like I described above, you could get true low light ability. About the noise, is it much better on a cool day compared to a hot day, then it is probably thermal noise and dark current. Removing the lens and applying a cooling method would reduce the low light noise problems.

So would anybody like to try these with their own camera (you don't have to replace the lens to do it)?

GRHD1 Service manual available on Ebay at the moment.
 

Re-edit: Whoops already covered.

I remember why I was posting here, I found what looks like a service manual for the HD1 going on ebay, if anybody would like one.

http://cgi.ebay.com.au/JVC-GR-HD1-GR...QQcmdZViewItem

Out of curiosity, I know the GYDV500 is supposed to have a hidden uncompressed video port, are there any in these cameras, any hidden ports/sockets/pins at all on the boards? You guys have the schematics is there anything there?

I wonder if formatted uncompressed information can be tapped along the process path without having to go as far as Andromeda?

I looked but couldn't find anything, do you have a link Graham?

The camera produces a lot of heat inside which is designed to be dissipated by the aluminium frame (there is a heatpipe going to it from the DSP/encoder chips) - this surely drives up the dark current and noise of the CCD imager. I have some ideas around the CCD frontend and did some work in bypassing primitive one-BJT current sink JVC put for some reason at the output of the CCD before emmiter follower. No controlled tests yet but it surely did not make the situation worse.

The simplest way to shoot 24p on 30p would be to swap all crystal resonators in the camera for 20% slower ones and then play back the tape in the similar camera for normal acquisition of 30p source which is now in fact 24p timebase. All operations are controlled either directly from XTAL frequencies or via PLL controlled circuits. Shutter speed, frame rate, tape speed, drum RPMs, etc.

I've got it. It's not that useful.

You wouldn't believe I posted a more primitive form of this idea before and forgot all about it, but I now remember I posted a link to it, I thought here, so you guys could look at it, but I don't see any.

Here is the thread, and it adds a little more to the Scheme:
http://www.dvinfo.net/conf/showthrea...793#post460793



Leo,

This sounds good (if programmable even better), the trick is the compression engine works at 30fps. If the engine timing can't be changed, it might be possible to do the sensor frames at 24fps out of sync with the 30fps compression engine, similar to the shutter idea except sensor replaces external shutter, and frame buffer replaces 30 fps sensor storage. This could be done by giving it a blank frame every sixth frame from the frame buffer (either by changing buffer address, or filling with black, or inserting a fake black signal). A little more complex but more compact than external shutter

Patrick,

Is there anything to trace on there that might represent an output, or a place to tap, uncompressed video.