Vertical projection

[jmdh]

I've had a scout around at info online (blue-room and elsewhere) about this, but have come short when it comes to practicalities.

 

I'm after a projection solution on a shoestring budget, to project vertically onto a stage from a lighting bar. I'm taking as a starting point that any projector I can beg/borrow/hire cheaply is not going to come with vertical flying hardware, even if the projector is happy with the idea, so I'm looking at getting a first surface mirror (https://www.amazon.co.uk/Optical-First-Surface-Mirror-ST-GS/dp/B00BARO9LS looks ideal), But how to mount it? I have access to a stock of short scaff bars, kee clamps and regular scaff clamps of various sorts, and plenty of wood, but I don't want to fudge something that's going to be suspending glass above actors so interested in all advice. Any thoughts about how to securely make or acquire something suitable would be much appreciated.

I am assuming I'll have to bridge between two scaff bars to get a mounting position in front of the projector, but if there is a way to do so directly from the projector position that would be even better.

[kerry davies]

I may be being bonkers again (not unusual on BR) but what's wrong with a wing mirror? They come in all sorts of sizes and fixings, the western mount at top and bottom on vans and trucks would be my first thought.

 

If just a logo or a still or a rotating still image then there are umpteen commercial logo projectors for shop entrances, backdrop projection and the like.

[DrV]

I may be being bonkers again (not unusual on BR) but what's wrong with a wing mirror? They come in all sorts of sizes and fixings, the western mount at top and bottom on vans and trucks would be my first thought.

 

If just a logo or a still or a rotating still image then there are umpteen commercial logo projectors for shop entrances, backdrop projection and the like.

Wing mirror is silvered on the back of the glass so you get double reflections and also a bit of loss going through the glass twice. Surface silvered mirror is silvered on the err... surface. Depends on how high quality the image has to be.

[jmdh]

Hmm, interesting idea! I would have assumed wing mirrors are convex, but a cursory web search suggests that some are indeed flat. I'm not sure whether they are first surface though - I suspect not (meaning ghosting of the image, AIUI). It's a full motion video which needs to cover a wide playing space, so having a large enough mirror that it can be mounted somewhere sensible is another concern. For a 4m wide image approx 4m throw (ie a 1:1 lens), there's a 1:1 ratio between the width of the mirror and the distance you'd need to mount it from the source (which in optical terms will be *hand waves* behind the front of the lens.

FWIW the piece is here

. In that performance (which I wasn't involved in) they used a projector at a steep angle up on the grid, but it'll work better if it's truly vertical (with actor lighting supplemented from the sides) I think.

[david.elsbury]

Manfrotto magic arm and clamps?

[timsabre]

If yoy can find an old overhead projector, use the mirror assembly off that, they are surface silvered.

 

Though many projectors can be used vertically and you might be making this harder than it needs to be.

[Jivemaster]

words like Secol and Unicol searched on google get lots of hits for projector hangers most of which seem to be "system" products with some flexibility.

[sandall]

If yoy can find an old overhead projector, use the mirror assembly off that, they are surface silvered.

It used to be easy to buy replacement OHP mirrors - worth a search ?

[Brian]

Though many projectors can be used vertically and you might be making this harder than it needs to be.

 

^^^That.

 

Surely if you're having to concoct a lash-up to suspend a mirror above people's heads then you may as well just sort out something to run the projector vertically?

[timsabre]

 

Surely if you're having to concoct a lash-up to suspend a mirror above people's heads then you may as well just sort out something to run the projector vertically?

 

That's what I was thinking... And you do lose quite a bit of brightness going through a mirror, apart from all tge difficulties rigging it and lining it up.

[sunray]

I've never been able to work out why people are so concerned about mounting projectors. We seem to be happy with hook clamps while rigging lamps and speakers etc but when it comes to projectors we freak and expensive Unicol is suggested everytime.

 

Most projectors have 'mounting holes' on the underside and the spacing/dimensions will be in the instruction book. I'd be looking at things like: drops of short ali scaff (or unistrut) and drilling to accept the screws, or fabricate extensions on a couple of hook clamps. Both ideas will put the projector in the vertical position. Don't forget safety wires.

 

 

I once used a piece of ali sheet as a replacement for a ceiling tile and used 3 lengths of M5 studding to mount the projector about 50mm below the ceiling, once painted it matched the rest of the tiles and in my opinion looked a lot better than the bracket arrangements originally proposed.

 

[david.elsbury]

I once used a piece of ali sheet as a replacement for a ceiling tile and used 3 lengths of M5 studding to mount the projector about 50mm below the ceiling,

Did you verify the drop ceiling could take the additional weight of your projector and cabling ? Having seen how some are suspended, I wouldn’t be putting any additional weight on them...

[Dave m]

I'd just hang it vertically. You can simply do a "rubbing " of the underside to make a pattern of the holes if the manual's not to hand. A load of threaded rod about M8-10 is useful and if you make the base out of Ali then you can also make some folds so that you have somewhere for the rods to mount

You might find that a short throw projector might be better but they project off centre so check

I have hung a projector vertically with a magic arm and superclamp

[sandall]

I think I would want to know its internal construction before hanging a budget projector vertically - you could be putting a considerable strain on the fixing points.

[sunray]

I once used a piece of ali sheet as a replacement for a ceiling tile and used 3 lengths of M5 studding to mount the projector about 50mm below the ceiling,

Did you verify the drop ceiling could take the additional weight of your projector and cabling ? Having seen how some are suspended, I wouldn't be putting any additional weight on them...

Of course, the ceiling fixers were on site at the same time as me and we sorted it between us.

 

Flou light fitting have been hung from the grid with silly little clips for years and 4x2ft flou panels have replaced tiles for nearly as long.