Adjustable aperture masking?

[norty303]

Adjustable aperture masking?

Has anyone found a decent adjustable mask that is suitable for afixing to the front of a projector, rather than just botching it up with bits of metal and tape?

I have seen some with small thumb screws so you can wind it up and down as needed but no idea where to start looking to buy one

[Doc]

You could just install a rivnut each side of the aperture, then you just need a u shaped plate with a slot in each side and a couple of thumb screws.

[dsli_jon]

Yo Sir Nortymon -

Adjustable aperture masking?

Indeed, very fine suggestions, all - here's one more that us 'sekret squirrelz' use:

http://www.norcostco.com/blackaluminumfoiltape.aspx

Yeah, it's a pretty-penny, but, used-sparingly, a roll will last you a good couple years, and the stuff is the shizz for any 'custom'-type aperture, ie: curved or circular, for like an entrance-tunnel, etc; or for-when you have an 'over-under' situation, ie: indoor theater, with a mezzanine, where you've got audience above and below; or an outdoor shed, where you've got to protect an audience, down-low, and the skies, etc...

Light-tight as coal, and, like it claims, won't burn and can be re-positioned w/o leaving any nasty gummy-goo, like even good gaffers' can... (And we won't even discuss the forbidden spawn-of-the-devil, 'duct tape'...)

Rather than trying to ship it frome here, it - along-with its adhesiveless-cousin, 'foil blackwrap' (which is what to-use when you've got a large area to-mask, ie: beam-table-cover / experimental-set-up, etc ) - is a staple of the theater / film / photog-industries, so any decent photo / lighting / theater-supply house should have it, over yonder....

...But indeed, a very fine suggestion from the Royal Highness of The Hairy Tea Drinking Apes Society, there...

cheers...
j

[Lasermad]

Jon , im with norty on this one ! im fed up putting tape over apertures , particulary as once as it was raining it moved ...i think norty , and myslef are thinking more along the lines of this aperture shown below , an adjustable and once tightned up rock solid beam mask....can it be purchased off the shelf so to speak and attached to any projector , its unlikely of course but who knows ! maybe someone out there is supplying.

[dsli_jon]

Hey Sir Paul -

Jon , im with norty on this one ! im fed up putting tape over apertures , particulary as once as it was raining it moved ...

Oh for sure! - not suggesting the foil tape it in replacement-of, but, rather in-addition-to / something like the kv-plate... just testifying that that specific-product, is solid, light-tight, and won't budge on ya, even wet, (till you want it to) then, comes-clean...very flexible / helpful item for the 'road-kit'...
like we say over here, '...once you go BlackTak, you never go back'....

Unless yer talking like 10 of them or something, seems like you highly-capable blokes should be able to knock-out a 'kvant-knockoff' aperture-plate in yer sleep...
even without a proper mill, worst-case, that thing is just a band-saw, 4 holes, 4 dremel-slices, and a little filing-away...

cheers...
j

[goninanbl00d]

A slightly silly idea that might nonetheless work-

You know barn doors? Mount a set to the front of your projector.

(no, that wasn't a joke. Nor a cue to raid someone's farm.)



Those things. They're fully adjustable, and once set in place, they stick, and are easily movable. They can't do 'odd' shapes such as circles, though, but for most purposes these shouldn't be a problem.

You can get these to fit a wide variety of Fresnel lanterns, from miniature to large. They're cheap too, so for a cheap, adjustable aperture, why not.

[dnar]

A slightly silly idea that might nonetheless work-

You know barn doors? Mount a set to the front of your projector.

(no, that wasn't a joke. Nor a cue to raid someone's farm.)



Those things. They're fully adjustable, and once set in place, they stick, and are easily movable. They can't do 'odd' shapes such as circles, though, but for most purposes these shouldn't be a problem.

You can get these to fit a wide variety of Fresnel lanterns, from miniature to large. They're cheap too, so for a cheap, adjustable aperture, why not.

No no! Not the barn doors! Gives me nasty flash backs to the 80's... I had a set of barn doors fall from the grid and land on my scone once while I was mic'ing up a drum kit between acts... Left a nasty hole in my head!!!

I have also seen a gel frame fall 40+ feet and land on a member of the front row Audience... serious injuries. Nasty shiznits.

/back on topic.

You can actually get pretty small barn doors that would be the right size. I have a lamp here I used to use to light my effects rack, that includes mini barn doors.

[goninanbl00d]

No no! Not the barn doors! Gives me nasty flash backs to the 80's... I had a set of barn doors fall from the grid and land on my scone once while I was mic'ing up a drum kit between acts... Left a nasty hole in my head!!!

I have also seen a gel frame fall 40+ feet and land on a member of the front row Audience... serious injuries. Nasty shiznits.

/back on topic.

You can actually get pretty small barn doors that would be the right size. I have a lamp here I used to use to light my effects rack, that includes mini barn doors.

Oh dear. Although I've never been unlucky enough to catch a gel frame or a set of barn doors with a bodily appendage, the floorboards in my school hall have.

It's a bloody sliver of metal. It cuts. It sticks in, be it flesh, wood, or whatever you've got on the floor.

/back on topic

So, no matter what you do, make sure they're firmly attached, not just "I think this'll do" attached. They're sharp slivers of metal, and given enough momentum (from a fall, for example), they will hurt, and they will hurt hard. So make sure it's properly attached to your projector/luminaire beforehand.

Also- you can get miniature barn-doors designed for halogen downlights, the aperture on them is usually 4x4cm or 7x7cm, which should more or less be perfect. Failing them, the smallest Fresnel lantern size is usually 10cm or so.

[norty303]

I have also seen a gel frame fall 40+ feet and land on a member of the front row Audience... serious injuries. Nasty shiznits.

I heard from a freelancer I was working with about someone who got killed on a major tour when a gel frame fell out of the grid, and the corner penetrated his hard hat... not something I choose to think about too hard!

I like the simplicity of the Kvant one, whilst I could knock one up, it would be nice to get a painted/anodized one made out of something a bit more solid than ally.

Anyone fancy finding out how much their metalworker could knock a few up for, with anodizing? Perhaps get a batch done at the same time as module parts. We'd just need to come up with an overall size and slot spacing

[Phredy1]

I had my sister's husband build me this. It works great and a simple build. Any sheet metal worker should be able to whip something like this up in just a few minutes.