Used 8 inch Fresnels

[Todd Terry]

[Richard Crowley] “I regularly blast people who come through audio forums for trying to cheap things out where it isn’t appropriate, so I probably deserve some of the same for trying to do the same thing in lighting.”

Yes, Richard… yes you do. 🙂

But I won’t blast you.

I’ll note though, you told us what you are intending to do, but you didn’t really ask a question in your post.

Is your question:

A) Is this a good idea?
2) Where can I find these instruments, or
C) What is the capital of North Dakota? (it’s Bismarck).

If your question is “2”… hit eBay. There are always boatloads of used fresnels there in various sizes… and, various conditions, I might add. I’ve bought lots of them really cheaply there. In the past I’ve found some great deals on 8″ish 1K fresnels that I bought to turn into 575w HMI heads.

T2

__________________________________
Todd Terry
Creative Director
Fantastic Plastic Entertainment, Inc.
fantasticplastic.com

[Richard Crowley]

Todd, you caught me! I think I am asking both questions 1 and 2. I’m not that up on lighting but I generally know different kinds of instruments (Fresnel vs. elipsoidal, etc.) And I am trying to get the best value for the budget. I think that Fresnel seems like the best combination of functionality, flexibility an value. And it seem like 8 inch (500W – 2K) is the right range for my anticipated throws, light levels and power available, etc. I am looking for some advice on whether this is the right path. And I am also looking for help in finding some good values on used equipment.

Do you have a source of parts to make HMI conversions? I am as much a hardware hacker as a producer and that sounds like a terrific DIY project.

(I already knew the capital of N.Dakota 🙂

[Todd Terry]

Hi Richard…

Yes, I think fresnels are probably the way to go. Be careful about power, though. Since you’ll be shooting in other people’s locations you’ll find, if you already haven’t, that power supplies can be dicey. Churches, especially older ones, can be especially bad. We shot a political commercial in a church once where we had bunches of HMIs (1200w fresnels and PARs, and 800w Joker-Bugs)… and about 10 miles of cable running throughout the place since we couldn’t put more than one on each circuit. And this was a 100-year old church with about a dozen different breaker boxes in about a dozen different locations, and the church personnel didn’t even know where they all were, let alone what loads were already on them. You’ll have the same issues with 2K tungstens.

Again, I’d hit eBay for used fresnel housings.

As for DIY HMIs… it can be done, but parts are not easy. The heads are the easy part (you just have to have a big enough fresnel housing that can hold the ignitor, or build a little external sidecar for it). It’s the ballast that’s the royal pain in the patooty. I was specifically looking to build 575w instruments… we already had both bigger and smaller HMIs and I was looking for something in between. I found that ballasts (or parts) for cine-grade hot restrike Osram 575w globes were scarce as hen’s teeth, as my dad would say. The closest off-the-shelf thing you can find is a 600w growlight ballast… but they don’t work with the real thing. Fortunately I had an internet buddy on the other side of the country who was doing the same thing… but the abandoned the project for something else that came along, and I bought the parts that he had already gathered. He already had everything I needed to retrofit some big Colortran fresnel heads I had, except some jumbo heatsinks that I bought off eBay. I don’t know where he got all the parts, but I remember he had to look far and wide. I believe the main part of the ballast itself came from Germany, and I believe the ignitor was from Japan. Where exactly, I couldn’t say. The porcelain sockets are fairly readily available commercially, and the globes are standard Osram 575w HMI bulbs. It was a heckuva lot cheaper than buying a brand-new 575w HMI, but still not super super cheap… well over a thousand bucks in parts.

T2

__________________________________
Todd Terry
Creative Director
Fantastic Plastic Entertainment, Inc.
fantasticplastic.com

[Dennis Size]

2 comments:

A 2000w 8″ fresnel is totally inappropriate for a 50′ throw distance.
A 5000w 12″ fresnel would give you the lumens ….. but it’s a very inefficient fixture for that purpose. Stick with PARS.

An excellent source for used equipment is USEDLIGHTING.com

DS

[Michael Easparam]

8″ fresnels are adequate for a 50′ throw, but you’ll have to keep them locked in the spot position. A current Arri 8″ 2K will throw around 85fc @ 50ft in a 10ft circle. I would say you need at least 50fc for most things, so opening up the fixture a bit would probably give you around a 16ft circle @ 50fc. Blending four fixtures together nicely is only going to light you a 24ft wide strip.

I would be more concerned with where/how you are going to plug in 2K fixtures at 16a in random churches. I would stick to 1K fixtures that you can double when possible or separate when necessary.

If you want to go cheap, I recommend just going with basic par64 cans. No need to swap lamps around at that distance. Go with the slightly stippled/frosted narrow lamp (NSP) instead of the clear very narrow (VNSP) and get yourself some 1/4 and 1/2 diffusion to vary the spread.