Studio Fresnels vs. Theatre Fresnels: any difference?
 

I've been looking at picking up some ~500W fresnels. In looking at the various ligthing sources on the internet, I've noticed quite a price difference with not really any evidence of feature difference, between fresnels listed as "studio" fresnels and those listed as "theatre" fresnels. Given that the same lamp would/should be usable in either, is there any real difference in functionality between fresnels advertised for theatrical use and those advertised for studio use (aside from different mounting brackets, maybe...).

Thanks,
Matt

And possibly the plug. All the theater lights I've worked with had those big moosey rectangular prongy things.

I think there is a big difference, but I don't know how to describe it well. Video lights provide a very even field of light. Theatrical lights are much less concerned with that feature. I use theatrical lights for video, but almost always with diffusion, or as a bounce source, as your camera is much more sensitive to small variations in intensity than your eyes are.

That's called a StagePin plug. They've become the standard for theater installations. But you can easily buy/wire-yourself a conversion wire to Edison plugs.

Also, good luck with mounting theater lights on a stand. Each fresnel is metal with very large glass and weighs about 10-20 pounds. It's a very large difference.

I could take some lights from my school that they aren't using anymore (since we upgraded to StagePin) but they're so bulky I'm just going to buy my own light kit that's actually designed for studio use.

Check the diameter of the fresnel lens. In general, my sense is that for a given wattage light, "theatre" lights tend to be larger than their film and video counterparts. Weight is not much of an issue with theatre lights, but it sure is with film/video lighting.

The weight thing is only because we've gotten used to lightweight things. And that's pretty recent, yes? I go through my lighting books from the good ol' days and the things in use then were HUGE.

Wouldn't want to run'n'gun with an arc light, but....for sets? No prob. (Well, wouldn't want an arc light, anyway. Too much trouble. :^) )

There is usually a reason for the range of differing pricing.

Some fresnels have a feature known as 'pole focus', which means
that while still up at "trim height", you can reach up with a long pole
and adjust tilt, pan and spot/flood by grabbing on to knobs that
control them.

There can also be differences in mirror quality, heat handling,
lens quality, barn doors, gel frames, etc.

You usually get what you pay for.

I would think the most obvious and most important difference is that instruments for the stage are designed for longer throws than video lighting to be used on location or in studios (often smaller spaces than theatres). This means the lenses will focus best over rather different ranges.

Take a look at this data sheet: http://lms.leviton.com/openfile.aspx?docid=410

You'll see the specs don't start until 30 FEET out, producing a spot beam of 3.2 feet. Not something you are going to use for precise cinematic-style lighting in a living room.

Compare to the data for the lower wattage on arri site (http://www.arri.com/entry/products.htm -- sorry I can't provide a more direct link). The 200W fresenel is designed for throws that are shorter.

This does not mean you can't use the theatrical lights in some circumstances (like a TV studio), but that's just the point: their usability will depend on the set up/application.

A better example...
 

From my own experience, that is a bad lighting instrument to consider. Very uneven output, ridiculously heavy, mechanically a mess...

Try the 65Q from Altman Lighting (http://www.altmanltg.com/) as a much better sample of what folks here are considering. A 6" fresnel that takes a 1000W lamp is a bad idea. They get too hot, quickly fry whatever gel you put in front of them, and don't do what they are supposed to do. Almost all theatrical fresnels of this size take a 500W BTL lamp. You can also put a 750W lamp in them.

The 65Q shows data down to 14 feet. That is already almost too far away to have output similar to what a good ellipsoidal spotlight will provide at that distance.

When I light for video using such instruments directly, I almost always use two, three or more of them together, so that they provide a more even field. One instrument by itself is not going to do the trick.

Just to be clear, I was not reccomending the Colortran, just making a general point about different applications and throws etc.

The only heads in my kit are Arri which I think are wonderful, if a bit pricey.

Hmmm...
 

I use theatrical lights (pars, ellips) in the soundstage, along with a few Arris. Light weight ENG is Lowel but the large field kit includes a few ETC Source Fours. Those are theatrical lights but still use them in the field. Takes a larger stand to hold it up, but works beautifully.

Theatrical lights tend to be made for a longer throw, heat up faster and higher, and less durable than field lights or stuido lights. Also they dont nessecarily burn a clean 32k or 56k output. The Arri's and Colortrans (made in early 70's) in the news studio keep cool, are color accurate.

I work as a DP and gaffer in NYC, and I use Source Four PARs all the time. I also use the Source Four lekos (or "sharpies"). Depending on the situation, they can be great (punching through windows, pattern projection, etc). The PARs are a great replacement for Mole Mighties or smaller Arrilites -- they're really efficient and have a nice even beam spread (I use them for bounce sources, beam projection, and keying through windows in smaller locations). I've also worked with Strand Bambinos

http://www.strandlight.com/US/Index.htm.
http://etcconnect.com/product.overview.asp?ID=20084
http://etcconnect.com/product.overview.asp?ID=20086
http://etcconnect.com/product.overview.asp?ID=20080

Henry