I have bought a number of mounted film cells (ie, individual frames of film cellulose from a movie) and want to frame them and put them on the walls of my home cinema.

The problem is that when these cells really need light behind them in order to be seen clearly and so I need some way of putting them in a picture frame and illuminating them from behind.

I have had an idea which involves building a shallow box frame about 1/2" deep and putting a miniature lightbulb and fitting inside the frame along with a battery, connected to some kind of bellpush on the outside bottom of the frame so that the film cells were illuminated when you pushed the button. [I have ruled out the idea of having a light inside the frame permanently on due to the possible heat risk of melting the film cells]

I was thinking along the lines of all the pieces from a small torch (minus the body) connected through the frame somehow, or maybe bits from a kiddie's electronics kit taped up inside with a common/garden bellpush on the outside from B&Q.

Anyone got any idea where I could get the bits from for this? Or if there would be a more elegant solution to my problem?

[Bursar]

A bulb may be too hot. a flurescent tube may be better. There are smallish battery powered ones for use in a bathroom available, and that might better suit your needs.

Hi

You could try this method:

take two sheets of perspex (5mm or thicker) mark the size of the cell(s) on one sheet (exact size) and then coarsely sand out the inside of the markings.
Mount the cell(s) on the sheet that has been marked and sanded and then place the second sheet of perspex on top to sandwich the cell(s), place the perspex sandwich in a frame but leave the top of the frame open, now make a box in "V" shape the same length as the main frame but leaving a gap in the bottom of the V just a couple of mm wider than the perspex sandwich and install a fluorescent tube light in the V box, slide the V box over the top of the main frame and seal it with any sealant that will stop the light from leaking out (the idea is to force all of the available light to only escape into the top edge of the perspex).

I have seen this done before and is very effective.
you may have to experiment a little to find the brightness levels etc. but it does work very well.

The trick is to not scratch any of the surface of the perspex other than where the cell will sit as any scratches will be immediately visible as soon as you turn on the light.

You can also try this using two sheets of glass but obviously you can't sand it but you can easily etch it with one of those glass etching kits.

A friend of mine did this and it really did look quite stunning, although he never mounted the finsihed frame on the wall it was suspended from the ceiling adjacent to the wall.

just another idea to try

Bluey.

[Majik]

12v cold cathode. No heat problem and you can mount a bunch along a wide but short frame. Maplins for the components. Plus, you can have other colours apart form white if you want

Majik

Ok, I've searched around a bit on these cold cathode things and it seems like they need a lot of power. How do I connect one up to a battery - I've seen mention of an inverter although I don't know what that does? Also, how many batteries would I need? Bear in mind this is go inside a picture frame/box so I can't stick a load of weight or bulk in there.

If all I'm going to do is turn the lights on once in a rare while to actually look at the cells - and for the remaining 99% of the time the film cells will be sitting in the frame unilluminated - isn't it simpler to just use a small bulb or something?

[wandgrudd]

what about useing some small Backlighting Lamps

Maplin code :UJ70M

thay are the size of a fuse in a normal 13amp plug and would give just the right a mount of light off to see the film cells.


spec is
Volts Watts Amps
6.3V 0.6 0.1


idea being that you could power them of normal AA Batterys

eg 4 AA Batterys wired to give you six volts
as it would only be on for a verey small amount of time it should work fine.


you would need (all at maplin)

HF29G single AA battery holder x4
UJ70M Backlighting Lamp 6volt (should last about 5000 hours)
GW69A miniature microswitches

it will cost about £3.50 per cell to make if you only use one per cell.

[tonyb]

Cold Cathode/neon tubes work at high voltages (the cable on the ones I have is rated at 3kv!), and the purpose of the invertor is to take the 12V and 'step-up' to the high voltage required by the tube.

You can buy everything you need from Maplins, but I'd recommend ebuyer. They sell them for about £4 including an invertor. Theoretically you could feed the invertor with a mains adaptor, this is something I want to try, just haven't had the time.

I have a few of the ebuyer ones, and recommend them. The invertor is capable of driving two tubes at once. Each kit contains one tube, one invertor and the necessary cables. Look under computer case modding to find them....

Tony

Cheers, wangrudd.

I'm going to try your suggestion. I've ordered the stuff for one frame from maplin and will let you know how I get on. I've ordered 2 of the fuse lights in case they're not bright enough - the film cells are in a strip of 3 or 4 so I figure I could put one at the top and bottom of each strip

thanks again

Hmmm.

Sitrep: These "fuse" lights aren't bright enough I think. I think 2 per strip of film cells (one at the top and one at the bottom) would do it but (a) I only ordered one battery compartment (doh!) so I can't wireup 2 lights together (b) I have a couple of displays which contain 3-5 separate strips of film cells so that would mean me mounting 30-40 batteries into the frame to power that many lights!

I think I need to regroup and reconsider. Maybe 1 light with some aluminium foil strategically placed to reflect/maximise the light; maybe I just have to either abandon the idea or accept that I need mains connectivity and find a sparkie to wire up my walls.

I'm wondering why ordinary torch bulbs wouldn't be suitable? They only need 1-2 batteries each. But how would I "mount" them behind a frame and wire them up?

Wish I'd paid attention in 'O' level physics to watts, amps, volts, ohms, etc. Fiddling in the dark with all this electric stuff really...