Recording to Ninja Star from projector output?

[Ben Johnston]

I'm hoping to save myself time by recording the output from a projector into a hired Ninja Star. The projector is showing slides from a laptop and has HDMI output. I'm shooting the lecture and would then synch both recordings, preventing the need to insert each slide during the edit.

I anticipate possible issues with the HDMI output. I might not be able to change settings for this (frame rate, etc) and the projector might not even have this function. Any thoughts on this from Ninja Star owners? Any experience of achieving something similar?

Thanks
Ben

[Pete Cofrancesco]

I have a colleague who uses a ninja blade to record presentations just remember to feed it audio to make syncing easier. Obviously if possible test the setup prior to the event so there is no surprises.

[Oren Arieli]

It should work, although if the presenter changes resolution on the fly, or jumps between Powerpoint and browser, it could mess up the recording (exactly what has happened to me with BlackMagic recorders and game capture boxes).
The cheap solution is game capture boxes, which record a much smaller H.264 10-18 Mbps file on SD or usb thumbdrives. I do this all the time. Still get those random issues where recordings are cut-off due to laptop changes. The downside, is you can't see the input signal, since these don't have any monitors attached.
The expensive solution is with the dedicated external recorders, like the Atomos Ninja2, Shogun, BM Video Assist, etc. Biggest downside is that they burn through media, even at proxy-level bit-rates. Have big cards on hand.

Whatever you use, best practice is to have a 2nd camera focused and framed on the projection screen. It not only serves as a "CYA" backup, but can help you with sync and is very handy when a presenter insists on standing in front of the screen to point things out (or using a laser pointer). Neither of those would be captured on the external recorder anyhow.

The truly pro way to do this is to first run everything through something like the Decimator MD-HX, which can convert any incoming signal to an output signal compatible with your recorder.

[Jay Massengill]

A couple of additional notes to the great advice above:
If you have a second camera available to point at the projection screen as a backup, remember it doesn't have to be just a close-up of the screen. As long as it has the screen in the shot and good audio it will serve as a sync guide for the slides. And if framed wider than just having the screen in view it can serve as a useful second shot, say containing the presenter, the screen and a bit of the audience depending on the room arrangement. Even the most perfect camera closeup of the screen would likely be unsatisfactory to use as a final source IF you have access to the slides for later replacement if your HDMI recorder doesn't work correctly.
Also if only one camera is available, and you have doubts about the success of your audio feed to the external recorder, keep the camera running after the presenter finishes and zoom out to get the projection screen in the shot. This will usually catch something you can match sync on, such as escaping from the PowerPoint show or blacking out the send to the projector. Yes that would only give you a sync point at the end if you've shot everything closeup on the presenter, but if your recorder holds good sync with your camera but its audio feed isn't successful, at least you have something to go on later.