Karel Bata

You've just made me add a wire brush to the equipment list. Place needs a good swep anyway!

I'll PM you.

Such a range of prices to be found on the net. SAB, aka Working At Height Solutions, seem the cheapest by far. But are they any good? https://www.working-...olutions.co.uk/. I was going with Flints, but they stopped stocking scaff towers. . While I'm here, Flints only rent out 3m and 6m lengths of aluminium scaff. I'd have to buy the shorter lengths I need cut to size for me. Not ideal. Anywhere else to go to rent aluminium scaff? I'm in London.

Well that put me off. Thanks guys! Though... I could always buy it on the Amazon site and send it back if it really is that bad.

Stumbled across the 'Sol Custom Image Gobo Logo Projector Light by Gear4music' https://www.gear4music.com/PA-DJ-and-Lighting/Sol-Custom-Image-Gobo-Logo-Projector-Light-by-Gear4music/2ITK Anyone tried this? Only £45. Probably too dim for stage work, but it could have its uses, and I am curious...

Interesting stuff. It's fun to experiment isn't it? I think the mirrorball is a very underrated piece of lighting kit. I'm still discovering it's potential. (Geddit?) Gonna try out my star idea soon. I wonder how much it would cost to get a front-silvered mirror ball made?

Not really. If you stand where the mirror ball is (or hang from a lighting bar next to it, but I recommend standing ) you will see all of the light source, not just a portion. This is what the mirrorball 'sees' and reflects. The optics of this is quite complex and counterintuitive. I have a mirrorball next to window right here, and it's sunny. On the wall next to the window the images are rhomboids, distorted squares: But on the wall opposite (behind the camera) they are circular - where the little mirrors act as pinhole cameras and create a blurred image of the sun. You can see the transformation as they turn into circles beginning in the pic on the right hand side. So if your lamp has a circular exit for the light, as most do, you would see circular dots on the stage floor. If it's rectangular you should see squares. In theory, if you put a large star shaped cutout into the gel frame holder you should see stars. Anyone ever tried that? It would be like that trick for creating heart-shaped bokeh in a camera - You should be able to do that with a mirrorball. I might give this a try. Someone could write a book on this!

And (following on from adam) lights placed closer to the ball produce patches (rhomboids even!) that are out of focus. Sharp edged shapes are much more distinct. Try using a laser beam - the effect is awesome! You'll need a lens to defocus the beam slightly.

I rather like the Chauvet pinspot https://www.amazon.co.uk/CHAUVET-DJ-LED-Pinspot-Light/dp/B003N7BCFE/ref=sr_1_5 A surprisingly punchy little light. You can buy additional lenses on eBay to change the focal length to get a really tight beam. I'd be curious to know how well this performs next to the higher powered LEDJ fixture from prolight.

Thanks!

I'm only going by the spec sheet the OP posted - see up top. I've no idea how reliable Ledj fixtures are, but if the spec says 400Hz and it turns out not to be I'd send it back.

OK, it's drapes. But it's also got lights! And starcloths are in the LX dept. aren't they? So I've got a 3 - 3.4m drop. One is 8 - 10m width, and possibly another of 5m. Can be constant or (preferably) flickering. Hire period of a month. Any suggestions? Many thanks.

You're in the UK with a 50Hz mains source? But actually that shouldn't really make any difference as the unit gives the LEDs a 400Hz refresh rate. So is your camera perhaps set to 30fps, or (a bit fancy) 24fps? Try 25 or something that divides into 400, and the shutter set to 180 degrees. The lamp could be faulty. It happens.

Sorry for delay. Seemed polite to come back and follow-up. Good questions Ray. I've got eight(!) of these projectors - though two are now dead. They used to go for $2k, but that's plunged since because they're pre-HDMI. I was gifted two and then bought more on eBay. They're compact, light, trouble-free, and they allow you to take out the color wheel thus increasing their rated 3k Lm to monochrome 4k, which is perfect for a lot of what I do. Why put the vents on the bottom? So, upside-down... Your post worried me. I have used these several times upside-down for a few hours with no probs. And the top is flat - it just invites you to flip it over. However I looked in the manual, and there's no mention of flipping it. Nor anything saying not to. Nada. A bit of an oversight methinks. I searched on the web for the lamp specs (which I couldn't find - lamp is U5-200 if anyone's a genius at this!) but the lamp doesn't look the type where it make any difference. And I'll be running in eco mode so it won't be at max heat anyway. And I'll keep spares on tap. Cheers!

Thanks for the input. The projector will be secured on top of the ply, which will be U-bolted to the scaff. The scaff will protrude by 1m, and the projector weighs 2kg.

I'd been mulling this over for way too long, and then had a brainwave! Rather than using one scaff bar, why not use two side by side? The two bars would be attached to the beam using four scaff beam clamps. A sheet of plywood is secured firmly between the two bars using 50mm u-bolts. The projector is then secured to the ply sheet - which is an easy matter. The projector only weighs 2kg - less than the scaff! A budget solution that's quick to rig, and should be rock solid! I'm not missing anything am I?

Thanks for the pointers. Will do. Yes, the info on the LEDs was a bit minimal. As to the mirrorball - the way it is constructed the mechanism that supports the ball inside the box is independent of the drive and is connected by a rubber belt. I thought that was clear from the pic. So changing the motor won't affect the safety aspects of the ball. If it doesn't work, or even buns out(!), the ball will just stay up there. It's why I bought this particular rotator. I gave the weight of the ball (50g) as an indication the starting torque required (though that doesn't take account of the mechansim's friction or the initial oomph to get it all going).

Thanks. Those torches are amazing. But I need something that's 2 to 4 times brighter - one red and one blue. They need to be on for a long time and focussed tightly to about 0.3m diameter at 2m distance. I was going to use lasers (I even did a laser safety course!) but I got put off that by some nasty safety issues. So I'm wondering if I took the optics off a torch and added a more powerful LED... Now I have to find the LEDs and heat sinks. Must be a specialist company somewhere. LEDs are everywhere now. And so quickly!

OK. Thanks Tim. I use forums like this to bounce ideas around, particularly for really out-there experimantal stuff. In the end though I often go the well-trodden route (I'm really an absolute stickler for safety and will be the first to say no) but even an unfruitful investigation yielding only wild ideas is all grist to the mill and later on can maybe be put to use. Fact is, it's fun to throw stuff around and see what turns up. The first person I saw doing that prifesionally was David Hershey on Cats. A lot of interesting ideas never made it into the show. And I wouldn't have done a fraction of the stuff I'm proud of if I'd just stuck to the rule book. Happy to be told I'm wrong, but that lecture crossed the line. Cheers!

I'm building a light source for an immersive arts installation and am looking for a couple of really bright but small LEDs. I was going to use lasers, but this will be in a venue for a month, and I'm not happy leaving lasers unattended. Any ideas?

Good grief. How rude. I've been doing this kind of stuff for a very long time. For instance, I created Europe's first projection-mapping rig back in 1981 - before you were born sonny. No accidents yet. It's always bugged me that there have been a surfeit of upstart AV technicians with rule books tucked under their arms ready to tell lanyone they're somehow breaking the rules. You see them all over the world. "Oh you can't do that." Good for the ego is it? Grow up.

I think I've found a solution now - a high-torque reversible 12v geared motor nominally running at 1rpm (£6 from China!) and this https://www.ebay.co.uk/itm/1pc-12V-24V-48V-40A-DC-Motor-Speed-Control-PWM-HHO-RC-Controller-2000W-MAX-9-50V-/401868754256?hash=item5d913e8d50

I have this rotator. The motor has internal gearing making it turn the shaft at 1 rpm, which means the rectangles reflected off the mirrorball go around the room at 2rpm. I'd like that to ba a lot slower. At least half that. Anyone here able to point me to suitable motor and potentiometer? Or suppliers? I'd be very happy for this run at 12V and put a transfomer powered from mains into what is a very spacious box.. The 50cm ball weighs 50g.. Now to images. Hm... Sorry they've come out so huge!

This camera mount popped into my inbox yesterday (it being Black Friday). And I thought, "hm..." £36, inc delivery. It's an imitation of something more expensive, but I bet it works ok. Now imagine that upside-down, with the 'camera' mounting hanging below and supporting a platform holding the projector. It says the max load is 17kg. I doubt it would really go that far, but my projector is 2.5kg (including cables and player). Not sure I'd be happy about it all hanging on a 1/4" thread, but that can modified. Anyway, there must be other similar mounts out there.... Thoughts? . EDIT: worth mentioning that I'm using a 3.5k lumens office projector. Unlike an event projector, these don't point the beam straight out, but at an angle to the horizontal axis, so the projector's body is more or less horizontal when projecting up (from a desk) or down (from a ceiling). My point being that the projector wouldn't be pointing down at an awkward angle and putting a strain on this mount. It would be horizontal, though still need a little adjusting. It's like this...

Thanks Tom. For the bit of floor I plan to get people to walk on I'm going to buy some gray Lino - 7m x 4m. A shame it doesn't come wider. About £200. I'll fill the bigger holes in that concrete floor with sand, dampen it, and lay the lino on top.