Datapath capture card

[Kumamoto]

Every setup I see people suggesting involves using external BlackMagic capture cards.  I'm looking at building a machine to run Isadora but I'd prefer to use a Datapath capture card in a PCI slot to a BM over USB for reasons of latency and compatibility with the rest of my hardware.  Does anyone have experience with this?  Will Isadora be able to talk to the Datapath card?  I'll probably be using SDI inputs, but DVI or composite isn't out of the question

[DusX]

@Kumamoto

There are pci cards from Black Magic as well.

I suspect the Data path will be seen/work since they are sure to support standard interfaces, what you won't get is the lower latency Black Magic api drivers. Since Isadora supports the BM drivers via their api rather than a standard interface you would likely have less latency with BM hardware. 

Many users work on laptops hence the usb externals being recommended.

[Fred]

@Kumamoto I will second @DusX 's comments but add, if you are looking for some very specific performance increase for live capture there is also the option of the high end bluefish cards. Blackmagic with PCie and using the SDK through Isadora can give very low latency (I measured less than 2 frames from camera to laptop screen over thunderbolt). The bluefish cards can reduce that in a serious motherboard and a serious CPU with enough PCIe lanes that no other resources are shared (this is pretty hard to achieve). 

The next best latency reduction is genlock, the process of reclocking incoming signals can take up to a frame, getting a capture card and cameras with genlock is the best way to reduce latency.

[Skulpture]

@DusX said:

@Kumamoto
There are pci cards from Black Magic as well.
I suspect the Data path will be seen/work since they are sure to support standard interfaces, what you won't get is the lower latency Black Magic api drivers. Since Isadora supports the BM drivers via their api rather than a standard interface you would likely have less latency with BM hardware. 
Many users work on laptops hence the usb externals being recommended.

 I am exploring datapath too. I am sick of BM devices being so finicky and fussy. To be fair; they are designed for production studio's and broadcast; meaning plug in and set up once and change the setups hardly ever. I think we are in the world where we switch formats, cables, inputs frequently.... Anyway...

I am have been looking at this:

https://www.datapath.co.uk/vid...

A simple dual HDMI capture, low profile and a decent price. I am talking to datapath to see if they can test it with Isdaora. It runs on 'the Microsoft AV stream model, VisionLC-HD2 inputs can be accessed and enumerated in any DirectShow or Media Foundation supported application.' (https://www.datapath.co.uk/vid...) So I am presuming Isadora can see it with it being DirectShow?

Just as a side note; D3, AI and GreenHippo all support datapath primarily. 

[Fred]

@Skulpture D3 uses blue fish capture afaik

[Kumamoto]

Thanks everyone, all helpful information.  Watchout also tends to play nicer with Datapath than with BM - though they are both supported - so given the high probability this machine will get commandeered for running Watchout in the future, I'll probably wind up sticking with a Datapath.  @Skulpture if you hear back from Datapath I'd be interested to hear what they say

[Skulpture]

@Fred said:

@Skulpture D3 uses blue fish capture afaik

 Forgot about BlueFish; I think they do now use them yes.