Need to lower light level without lowering the heat

[Roger Berger]

Hi

 

I am trying to take 2 hour videos for Youtube (cut to 10 min) using lava lamps as the light source. One problem I am having is some lamps put out too much light and they look like a white light, no color at all and the wax cannot be seen.  If I use a dimmer to lower the light to the point the wax and color can be seen then it will stop flowing.

 

I am working on a 25 watt Chinese yellow wax in clear liquid.  To the eyes it looks great.  If I use a dimmer to lower the light to the point that yellow shows up in the video the wax will stop flowing.

 

I have tried to place a piece a aluminum foil on top and around the bulb and the last attempt was a 1 inch square and this allowed too much light so it did not help.  When I used enough foil to bring down the light to the right level the wax will not flow.

I lined the inside bottom with foil and wrapped the bulb - failed

Since the bulb is putting out the same heat, I guess that the heat is directed to the sides. 

Some ideas I can think of :

 

- paint the bulb with heat resistant paint, found a spray rated at 1500 F for about $20.  I found Quartz Coat (2000 F) that is used to coat quartz projector bulbs but it is about $100 a pint.  Hope to find a cheaper solution.  I do not know the temp of the bulb.

 

- smaller wattage bulb (for less light) and install a resistor for more heat (if anyone has done this what size).  I am thinking of wiring in a 20 watt resistor. 

20w/110v = .18a say .2 a

 R=E/I  = .550 ohms 

 

These two solutions are tuff, one costs $100 and the other a lot of work

 

Get some high temp gasket material and line the bottom cone to keep as much heat from going out the sides.

 

Any other ideas ??

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[Tim Gill]

I think the only solution to this is to install a heater and a low wattage or LED light cluster to the lamp. - Trying to use a macincal dimmer (i.e. covering the bulb) wont work as well as the heat will be reflected back to the lamp and cause over heating to the bulb and surounding arear.

Somone on hear did try a simmler methord to create a LED lava lamp, however I don't remember who it was.

[Mr MaGoo]

Here you go...
http://oozinggoo.ning.com/forum/topics/smart-century?

[Jack the Reefer]

I

[Jack the Reefer]

How putting something that covers the light bulb paritally, like a metal bar or foil, just block some light. That way you still have all the heat from the bulb.  You could also use expanded metal, sheet with little hole for diamonds shapes, would block some light, metal screen.  To measure the lamp I bought a laser thermometer of Ebay from a seller in China or HongKong and it was 10 dollars with shipping.  Good luck

[Tim Gill]

The reason i am saying about not using the foil idea is that from my experance with lighting equipment when a light sause is blocked the heat is reflected back into the areara where the bulb is - it may be diffrent with lava lamps so give it a try.

[Jack the Reefer]

I agree with Tim, foil is not a good idea, it doesn't have enought surface area to retain the heat, However I do think the expanded metal sheeting would block some light and the metal would heat up and maintain the temp.  I have some Xenon light sources that are used in surgury *now for fiber optics* that use that method to reduce the light output.  Metal screening I think would also work,  When I take photos with low light I use a Maglite led flashlite as extra lighting, that way you can highlight certain areas.  Experiment with different methods, it may take time but you are on the journey and hopefully you will find a solution, or several solutions.

[Gwen Williams]

what about theater gels in a similar yellow they will brighten the color without removing any of the brightness or heat, they will simply color the light

[Tim Gill]

That could work - you can get gels which just reduse the light output, the thing with gels is that they do brun through depending on how dark they are and how hot they get so you may find that you keep on needing to replace them.

However you could try using hard plastic gels for par 36 pinspots they are more durable https://www.storedj.com.au/products/ULA-ICF1004P

Gwen Williams said:

what about theater gels in a similar yellow they will brighten the color without removing any of the brightness or heat, they will simply color the light

[Gwen Williams]

there are ones made for high temp lights as well, they are a bit thicker, the hard ones that are meant for DJs, DJs rarely use as they are quite brittle and have limited color choices.  The high temp gels are called HT gels, pretty much any theater supply shop should be able to get ahold of them since more places are going tword hotter more powerful lights.  I get mine through norcostco.com both rosco and lee are great brands 

Tim Gill said:

That could work - you can get gels which just reduse the light output, the thing with gels is that they do brun through depending on how dark they are and how hot they get so you may find that you keep on needing to replace them.

However you could try using hard plastic gels for par 36 pinspots they are more durable https://www.storedj.com.au/products/ULA-ICF1004P

Gwen Williams said:

what about theater gels in a similar yellow they will brighten the color without removing any of the brightness or heat, they will simply color the light

[Tim Gill]

Gwen are you in the entertainment industury / lighting as well - it would be good to know that theres anougher lampie on hear as well.

Yea Rosco super gel or any Lee gel will work as thies are thicker but all gels will enevetably brun out. - Yes thearthers are using bigger lamps but they are often automated lights insted of static lights and gel rounds are done at set times to replace gels in the rig so the correct cloure is maintained and to ensure they dont brun out during a peformance.

 

[Gwen Williams]

Both my hubby and I are wedding DJ's and techies lol.  As DJ's we have used the plastic rounds, hated them with a passion, the limited color selection drives us crazy, we would rather buy a sheet of gels and have to re-cut every once and a while but still get the exact color we want.  Gels are cheap enough that it makes it worth while, plus think how many lava's a person could temp color with just one gel sheet.  I am giving myself ideas, make my clear/black into a pale pink/black or fuse a few and have rainbows.  OK, getting off track