Video for live demonstration

steveusk

I want to be able to show a live demonstration on a screen near where it is taking place, so that more people can see it.
We have a data projector and want to use this to throw the image onto a flat projector screen.
The demonstations will last about an hour and I would like to be able to set the camera up (on a tripod perhaps) so that it will broadcast the demonstration to the projector. I think I can use a HDMI cable for this...
What type of device (camcorder, action cam whatever) should I aim to use for an hour long presentation. Will batteries last that long in the camera? If not can I use the camera via a mains charger?
Advice please.
I don't need fancy features: just a simple straighforward way of showing what is going on (actually someone working on a pottery wheel) for an hour or so at a time. (If it does also record that might be a bonus but at this stage just displaying it would be fine. Sound, again, is not needed...

stearman65

A Camcorder or DSLR/Bridge camera with video recording will do the job. I wouldn't use an action camera as they don't have the features such as zoom. Also many don't use 16x9 aspect ratio & can give a distorted representation of your subject. I happen to have a Bridge camera for sale on here which would do the job admirably. However it is also on Ebay & has bids on it. You can see it here
FUJI FINEPIX SL1000 BRIDGE CAMERA MINT CONDITION  | eBay It is on here at £185, but I would accept £150, or you could try on Ebay.

Terfyn

There are some camcorders, particularly in the Panasonic range that require 5V from a USB supply to recharge the battery or to run the camera. I would suggest the HC-V770 which has a live HDMI output to supply the projector (I know this combination will work because I do exactly the same with my 750 and projector) The projector will normally run from the mains and the camcorder will run from either a mains USB supply or from a power pack such as an AUKEY 20,000mAh power pack.

noiseboy72

I do this all the time using a Panasonic HVC XC920 camcorder and Canon Xeed HD projector.

Please don't use a bridge camera or DSLR, as the colour balance and exposure may well change and you will have very limited control over even things like focus. Many DSLRs will only stay on for a limited amount of time - about 20 minutes before they drop out.

Terfyn is suggesting the right approach a mid range camcorder that has a "clean" HDMI output - with no graphics superimposed on it and has the ability to lock the colour balance and exposure. Plug it into the mains and turn off any power saving.

Check the screen shape and set the camcorder and projector to match. You might need to adjust the brightness and contrast on the pj, as data projectors tend to be optimised for graphics and video can look quite washed out.

Think about the lighting of the potters wheel. The eye is more forgiving than a camera and large variations in lighting or shadows will really show up on the screen. It's better to have a more consistent lower level than harsh bright spot lights.

Terfyn

Ambient lighting is the best IMO, so locate near a window if possible.
Oddly enough I have recorded a potters wheel on a couple of occasions, my grandson threw a couple of pots, under instruction, at a local pottery. I handheld the camera but the results were quite satisfying considering the impromptu setup. I would suggest the potter uses an apron of a contrasting colour to the clay to make the wheel and pot stand out.

12harry

Good advice Terfyn...may I add that behind the wheel ( inc. apron I will presume), should be made darker, so the image of the clay stands out. Also, I believe the session can be wet, causing splashes; so using the camcorder on a tripod at a distance is probably a good idea... but beware that HDMI transmission specs are for short cables. (This should suit your set-up, as described).
However, it may be rather boring for the audience watching the same scene-shot for an hour . . . It would be so much better if a second camcorder was recording the Professional,( e.g.  giving advice), using a different angle, with a personal tie-clip microphone.
Many projectors have more than 1-HDMI input, so it's possible to switch - but rather "clunky" - so an HDMI-switch would be better - not fully ideal, but v.much more interesting for the audience.

If you wanted to use the recording ( and why not?), you can arrange close-up shots and put them into the Edit as "cutaways" - this makes sure the audience is kept awake at all times.
As making a pot involves "firing",  this could be added like "Next Time..." to encourage the audience to watch the next one.
Hope that helps.

noiseboy72

I don't think a clunky crash switch is going to add much. It will be very distracting if the image disappears for a few seconds each time the shot changes.

For multiple cameras a simple video mixer is required. Roland make some really simple push button mixers for about £700 for the hdmi version, but for a demonstration, I think a single camera actually works very well. People will concentrate on the live action and look at the screen for the details. It's actually quite hard for the presenter if everyone is simply watching the screen all the time.

Terfyn

I agree with the one camera approach. The potter's wheel is a single object and there is no advantage in having multiple images of the same thing. The actual area of interest is really quite small and one camera concentrating on that would work better than multiple shots.
Some of us remember the potter's wheel interlude on the BBC. Happy days.

12harry

OP did say the recoding might be used for showing at other times.... that was why I suggested a second viewpoint.It wasn't clear (to me), if all those present had a good view of the presenter... otherwise why go to the trouble of the screen, which is only a 2D version of what they can see for themselves?
  It would need to be a large venue where the screen was preferable to the live-image.
Also, performing for a camera is quite different from normal presentations - as the camera has a very narrow concentration and is mostly unforgiving . . . if the presenter is trained in camera-work then having the audience close-by will be an additional distraction.

Probably best to wait for feedback from the audience . . . that may ( and should) be the Guide to "next-time".

Good Luck.