IR camera (for interaction)
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Use a surveillance camera with SDI out and a black magic capture box, I have linked many times on this forum to such cameras if you search, You will need to get a IR pass filter, the DSLRs and the BMPCC have an IR block filter built in, you would need to open and modify these cameras to use them for IR tracking, all normal cameras block the IR light from the sensor to get normal photographs. What you want to do is the opposite, block all visible or non-ir light from the camera (and make sure it does not have an IR block filter in it. Mid west optics make high quality IR pass filters.
Something like this camera, there are many variations I chose this at random it is not the one I use, read the specs carefully for output forms etc.I carry a kit like this a lot, a security camera, manfrotto magic arm, long SDI cable, SDi capture box, it will all fit in a small bag. You can find alternate lenses very easy (the security cameras use C-mount) you are best to get one with manual zoom, focus and aperture, depending on the height of the ceiling a 3.8mm lense should be OK, but this is easy to calculate.The trick with IR tracking is contrast, reflective floors, dark floors with dark clothes, and shadows will all mess it up. You will need to be careful about lighting and camera settings. Bring IR floods but you can also block visible light from stage lights with red green and blue filters all at once.Again there is a lot of good info already on the forum, a good search and read will give you more than enough info. -
Hi @Fred and @Mikemixed,
thanks a lot. Fred, your option looks great. Something like this I am looking for. I am not really gifted from technic standpoint of view, so I really look for simply answers. I looked at the surveillance cameras and its little beyond me.
I understand lighting on stage very well, including LED lighting options I just do not get how strong IR source I need as well as which cameras is cheap and works well for a stage which is cca 10x10.Mike, cameras you send looks great - just I am based in Austria.
But thanks a lot both of you.
Cheers. -
If you are coming from a stage lighting background, you can adapt Fred's CCTV camera solution quite easily and cheaply. I've toured shows with this setup using a projector and camera in the grid and a white floor, and it works fine, although not high definition: get an old b/w cctv camera with analogue out and a wide angle lens. unscrew the lens, cut small discs out of primary red, blue and a dark green lighting gel and insert them between the lens and the chip.
run a bnc cable from the camera down to a Canopus or Dazzle capture card.on stage, in each corner, place a fresnel or wide profile on a low stand. focus these so they're not spilling on the floor and then add the combined red/green/blue filters. (its good to max this channel at 40% because its going to get superhot if you leave it up at full and the filters will burn out in minutes)Then you can use the projector as a light source and Isadora will see the performers but not the projection. -
Thanks a lot. So I progressed - I have white/light gray floor in the black frame on the floor and blacked-out space, unidirectional LED stage lighting, projectors from (more or less top).
Do you think this camera would do the trick?
http://www.ebay.at/itm/Bosch-Dinion-LTC-0385-10-analog-monochrome-camera-with-movement-detector-CCTV-/122069991627?hash=item1c6bf040cb:g:gO0AAOSwMmBVsJ5cThanks a lot.
Tomas
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composite only, no controls to adjust the image....looks a bit dodgy
http://www.ebay.at/itm/2-Megapixel-Full-1920x1080p-HD-SDI-Sony-CMOS-Box-Weatherproof-Camera-Exmor-/181108186791?hash=item2a2ae39ea7:g:8Z4AAOxyOeBRyyeA -
Thanks a lot @Fred, but also to all of you.
I am have to shop after all the talks, anybody if you can share your thoughts.
2x supercplamp: http://www.ebay.at/itm/Manfrotto-Magic-Arm-Kit-143-Superclamp-Bodenstativ-/231126817360?hash=item35d03b5a50:m:mwOepVSdOSjyi3MAiNMEspA
1x IR light: which I am not sure but I am looking at following options
http://www.ebay.at/itm/Wetterfest-80M-CCTV-Kamera-IR-Illuminator-Infrarot-Lampe-Nachtsicht-/171760903274?hash=item27fdbf646a:g:Vo8AAOxy0aBRqKxaBM SDI to HDMI (in) capture box - which I am also not so secure:
https://www.blackmagicdesign.com/products/microconverters
and of course 20/30m SDI cable, which is the easiest part.
As always very, very big thanks to all what you spend your time to help!!!!
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looking at your shopping list - the camera looks good - with the right lens.
Manfrotto magic arms are pretty much essential.In my experience, all those IR illuminators have a very narrow beam, with no way to control the spill. it will probably be much easier to use theatre lighting and filter out the visible light.That blackmagic box won't capture, it just converts. [this](https://www.bhphotovideo.com/c/product/892453-REG/Blackmagic_Design_bdlkulsdzminrec_Ultrastudio_Mini_Recorder.html) is the one you need if you have a spare thunderbolt port.john -
John
Thank you very much! You spared me some hassle.
True about the spill. I am searching also something for rehearsals and tests.
Talking about this, I am bit worried about the filters as this will be prone to failure (I have already one place where its gonna be discussions with fixtures) - did you try to experiment to put IR light into the normal profile?
http://www.ebay.at/itm/Philips-Infrarot-Infrarotlampe-E27-150-Watt-R125-IR-R-230V-ES-Leuchtmittel-Birne-/351324645142?hash=item51cc94a716:g:PDQAAOSwPYZU7EkKTomas
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profiles use specific halogen bulbs. that Philips IR bulb is probably designed for therapeutic heat lamps, so not a good idea. you can get 1mm thick acrylic IR pass filters, but they're quite expensive.
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@ I see...Hmmmm I thougt so. There is no workaround.
One last stupid question - auto iris on CCTV - is it good idea? Or eventually filter makes things so dark, that IRIS goes wide open either - way?
I got offered lens, with auto iris and build in IR system. I have no idea how effective is IR for theatre purposes and how will behave auto-iris.
Thanks a lot in advance.
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Dont get auto iris, for tracking you want fixed manual settings
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Thank you @ Fred.
I realized, that camera as 1/2.8 sensor with C mount and the widest think I so far found as zoom lens, in order to save myself a pain is 3,5 - 8,0 mm but its designed for 1/3 sensors. Do you think it will work even with this small difference, or there will be some trap in tracking at the corners?
The whole thing is bit fiddly to get it right on first time.
I was hoping for something wider going all the way to 12mm.
http://www.ebay.at/itm/CCTV-LENS-3-5-8-0mm-F1-4-/131618869930?hash=item1ea51892aa:g:Co8AAOSwdzVXi7t7
I feel like to send everyone who helps me a bottle whisky
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And sorry - one more question. There are these IR corrected lenses for brighter images. Is this something which is good or rather contraproductive with IR tracking?
I found also this one: https://www.bhphotovideo.com/c/product/414195-REG/Tamron_12VM412ASIR_12VM412ASIR_1_2_4_12_F_1_2.html
If I managed the whole system, maybe I will post somewehre info for the lowcost IR system, so people after me dont have to go through this research and its easier for them.
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For tracking I get lenses here often
http://www.surveilzone.com/cctv-lens/cs-mount-lens there is a lot of cheap options so it is not expensive to carry around a lot of different lenses."I was hoping for something wider going all the way to 12mm." 3,5 mm is much wider than 12mm, I dont understand what you mean.I dont think these lenses are IR corrected, some lenses have a filter to block more IR and flare, these dont, always get the IR capable lenses to IR.Until you need perfect matching lenses, reliable repeatable distortion, matching back focus or other features just stick with the cheap ones, I never saw any huge advantage, the quality is better on the more expensive ones, but if you are worried about getting the right one, buy a few cheap ones(and doubles of them) instead. -
@ Fred. Thank you. I need C mount, but its ok.
I generally try to create small, flexible set ups, so I try to avoid buying too much stuff.I mean from 3,5 all the way to 12 mm. I need to be very wide I guess, but in theatre it can change.
I suspect, that with the consideation sensor size it will be at least 10,5 - 36mm and less I need to go wider, which I am not sure is possible, that should suffice once for all.If I got right, IR coating enhances IR light in terms of visibility and contrast, so that would be nice benefit.
I am not sure how I can use back focus effectively for tracking. Having focused everything on furthest place and use the fact that lens is so wide that everything is somehow in focus?
