Lighting

Posted on by
Back to Lighting...

Dimming a 650w tweenie? (3 replies and 5 comments)

nickgrow
4 weeks ago
nickgrow 4 weeks ago

I recently got a nice dimmer from Wooden nickel that can handle 1,000 watts. I’m really into dimming photofloods and 60w bulbs. I was wondering does anyone ever dim a 650w fresnel? Is it safe? Would it warm up the light like a regular incandescent bulb?

The Byre
4 weeks ago
The Byre 4 weeks ago

Assuming that it is an ordinary tungsten filament bulb at the back and not LED, CFL or something that has to have a choke or a transformer or any other circuitry before electricity reaches the light, an ordinary diode-driven dimmer pack will do the job.  There are loads of old-fashioned 10-volt dimmer packs and desks out there going cheap, as all stage and display systems are going over to LED and DMX controls (which are very similar to MIDI).

The 10V refers to the control signal sent by the controller to the dimmer pack.  This technology is NOT compatible with modern digital DMX controllers and LEDs.

A Fresnel light refers to the lense, it is what goes on behind it that counts when it comes to dimming.  If it is an ordinary incandescent lamp or bulb, it will get redder as it dims.  If you are in any doubt, talk to someone who understands this subject and can inspect and advise you on what you need to get.  

There are loads of cheap dimmers and some of the very simple small ones are all-in-one, i.e. they are the fader and the dimmer pack in one box.  Usually, these are just three- or four-channel little boxes and usually can go up to 1kW (check!)  

Look for brands like Pulsar, Anytronics, Zero88 and make sure that any and all lights and dimmer packs and dimmer controllers are clean, safe and compatible.  

Once again - if in doubt, talk to an old-fashioned stage electrician who understands this technology.  He will probably be wearing bifocals and is called Angus MacCrusty!

 

nickgrow
4 weeks ago

To clarify, I already own a couple dimmers that can handle 1,000 watts, I’m not in the market for a new dimmer, and I’m talking about dimming a 650w tungsten tweenie. For instance to color match with some practicals that will be warmed up with dimmers as well, thought I’d splash a tweenie off a ceiling to help lift the levels of the practicals and might dim to my liking. Just wondering if anyone else dims tweenies and if it’s safe?

Mike
3 weeks ago

Tweenies can be connected to variable Resistors (dimmers) and is safe to do so but the operational parameters are limited and so you have work out if it’s worth it, you can achieve the same effect using a smaller lamp (Inbetweenies). Using a dimmer also reduces the colour temperature of the lamp so it is limited in its use.
120 volts equals 3,200K, 110 volts equals 3,100K, 100 volts equals 3,000K
90 volts equals 2,900K. Percentage of light output roughly translates as 100%, 75%, 55% and 38%. Changing the current to the lamp will reduce the life of the lamp drastically so you have to work out the expenditure of light bulbs against buying another lamp type. If you are on a tight budget, then this could be a false economy. Bulbs are expensive. You could change your bulb to LED ”Relamp” which could be more cost efficient.

nickgrow
3 weeks ago

Thank you for the info Mike!

Roger Deakins
3 weeks ago
Roger Deakins 3 weeks ago

I almost always have my tungsten sources on dimmers and I generally run them at anything fro  80% to 20%. I like to adjust the warmth by dimming and find it difficult to emulate the effect with LED sources, I  guess, because they don't have the full color spectrum.

nickgrow
3 weeks ago

Very interesting thank you Mr Deakins! I assume you’re talking more about practicals than like mole Richardson or arri tungstens, do you ever use dimmers on those?

Roger Deakins
3 weeks ago
Roger Deakins 3 weeks ago

No, I was talking about everything, Mole Richardson Tweenies, Pups and 2Ks etc...

nickgrow
3 weeks ago

Thank you thank you thank you! That is a great insight!

Back to Lighting...