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View Full Version : Does the Phoenixcard genlocks it's self?



buchie
28-03-2009, 04:21 PM
We've just started up a tour with a Catalyst system and a Phoenix capture card. Over the whole line we experience some latency in the Live Projection.
There is something to win in the camera chain, but we try to straighten the whole system out.

1)Does Catalyst do any thing with the embedded Blackburst in the SDI signal?
Or can you offer a genlock signal to the unused input and lock the system?
We did a photograph test with timecode, and the latency was 1 frame which is pretty good I think. Not much to win here?

Our set-up:
2) 800x600 content and 720x576i SDI is mixed, and then upsized to a mix and output of 1400x1050 which is transported over DVI Fiber to enter the CLM R10+ in their native panel format. Does anybody See any crazy stuff here?

I'm open to any solution to bring wherever the latency down.

Thanks
Michel

NevBull
28-03-2009, 04:29 PM
Hello Michel

Catalyst does not have any genlock capability at the moment - you will have to use an outboard device to lock the output to.

regards

Nev.

buchie
28-03-2009, 04:53 PM
Hi Nev

I'd like to genlock the SDI input, not the output. The output is DVI-D and allready clocked to the projecter.

At the moment I can't think of an external device that genlocks the SDI signal en goes back in to the mac and tell catalyst here is your clock...

any suggestions?

cheers Michel

prodigal2
28-03-2009, 08:36 PM
Michel

You can only genlock the signal coming into the mac... but as yet you can't genlock to the mac.
Genlocking the signal via a switcher (grass valley/ross) is the only way I have done it, with multiple signal inputs. In truth though I have in not had any genlock issues via catalyst.

With your latency issue I would suggest you try the same test with the system you are using for the show. How many frames do you think you are loosing in the signal path? I find in Arena shows you can get away with 8 frames without it feeling too uncomfortable.
What is in the signal path to and from the catalyst? You mentioned a DVI fiber, I assume there are no DVI extenders in the signal path.

Phil

SourceChild
28-03-2009, 09:17 PM
The only time you Genlock a Catalyst is if you output the Catalyst into a converter scaler such as an image pro. Then, in that case, you genlock the scaler, not the Catalyst machine.

Input sources into Catalyst should be genlocked to the system if they are in the system but if they are run directly into Catalyst then they can be freerun.

I'm doing this exact thing now on a tour.
Cameras feed into the router and switch where they are genlocked. The router is patched to the Catalyst inputs. The Catalysts are run into ImagePro HDs freerun and the ImagePros are then genlocked into the Swicth/router where I can run them to record, IMAG, and the scenic projectors/LEDs.

samsc
28-03-2009, 09:27 PM
Hi Nev

I'd like to genlock the SDI input, not the output. The output is DVI-D and allready clocked to the projecter.

At the moment I can't think of an external device that genlocks the SDI signal en goes back in to the mac and tell catalyst here is your clock...

any suggestions?

cheers Michel

there is no genlock - in computer video world- you have to really remember vga and dvi are not video signals as per the world of sdi and hdsdi- VGA and DVI clock rates have nothing to do with sdi clock rates-

nothing is synchronised together- everything is frame buffered - genlock comes from a technological era when nothing was frame buffered - and mixers had to work with the video signal without being able to store it.

projectors generally do completely their own thing - they arent locked to anything - except the technology inside them which follows its own rules- with DLP its the DLP rates.

buchie
29-03-2009, 12:52 PM
We loose 16 frames in total, which is not acceptable.
we measured:
4-5 frames from connected phoenix source to CLM R10+ we should see this drop when we use the native resolution of the projector.

No DVI extenders, only a geffen spiltter

9-10 frames for the camerachain, which is outrageous, but that is because nothing is genlocked. It should be 1-2 frames...
we try to advise the company with a genlock plan.


testing testing....

cheers Michel

samsc
29-03-2009, 05:43 PM
We loose 16 frames in total, which is not acceptable.
we measured:
4-5 frames from connected phoenix source to CLM R10+ we should see this drop when we use the native resolution of the projector.

No DVI extenders, only a geffen spiltter

9-10 frames for the camerachain, which is outrageous, but that is because nothing is genlocked. It should be 1-2 frames...
we try to advise the company with a genlock plan.


testing testing....

cheers Michel

thats nothing to do with genlock- (genlock is just a way of synchronising the frames on video equipment before digital signal processing was fast enough )

genlock doesnt do anything to this at all-

this is the digital video processing pipeline.

every single piece of digital video equipment - including imagepro projectors cameras catalyst and whatever else - has to buffer at least a frame- and possible many more

imagepros have quite big delays when in certain modes....

---

exactly what do you mean by 9-10 frames for the camera chain? - please detail every single piece of equipment including splitters.

( on a large rock show 9-10 frames is 1/3s which is a distance of 100m for sound - so usually 9-10 frames means the video is in sync with the sound at front of house! )
light and sound reach the audience at vastly different speeds and on large shows the sounds is only 'in sync' at a certain distance - and at no other- if it is in sync for the band playing - then its not in sync for anyone in the audience ....

Mr_P
30-03-2009, 08:03 PM
The issues that Michel & Felix are having are not genlock related - they are due to frame delay in the Camera processing equipment and Barco projector processing. (not using native resolution)

The phoenix card is working as expected:


We did a photograph test with timecode, and the latency was 1 frame which is pretty good I think.

Genlock will NOT improve the situation. Only reducing the ammount of processing between the camera and catalyst will reduce frame delay.

If it is possible to turn off processing in the Barco Projector - that may also help. Most barcos have this feature, which means that you can use the native resolution of the projector chip. (This does mean that you have no other processing available in the projector though...)

Michael / Felix - I have emailed you separately

Simon