Conventional Fixtures - Which SourceFour lamp to use?

[Weisert]

We have been using,the 375w lamps in our ETC S-4's. We did that because of dimmer limitations. Now that we have upgraded to 150 2Kw dimmers it is no longer a concern. Should I begin changing my bulbs over to the 575w or keep the 375w and why?

[JustAShadow]

It would depend on how far your hang positions are from your stage, and how many fixtures are in your inventory. if your fixtures are lower than 20' above the deck and less than 25' horizontally, I would say keep the 375w. but if you are throwing farther than that, I would bump to the 575w as budget allows.

[gafftaper]

I prefer 575 long life lamps. My throw is about 23 feet. I typically run them about 85% but that's a good thing as it means the lamps will last even longer than the 2000 hours they are rated. It also means I've got about 15% headroom to bump up if I need a really bright moment. Change them as you can afford. Once you change a couple you'll ask yourself "how did I ever get along with so little light?" .

One problem waiting for you is it's hard to mix the two wattages. You'll definitely want to replace in strategically chosen groups. Replacing one at a time will make your wash really blotchy.

[derekleffew]

Originally Posted by gafftaper

...One problem waiting for you is it's hard to mix the two wattages. You'll definitely want to replace in strategically chosen groups. Replacing one at a time will make your wash really blotchy.

This is an "out there" suggestion, even for me, but if you can't replace "in strategically chosen groups," consider adding a cut of R97, 397, or 398 to the 575W fixtures if they are on the same dimmer as 375W fixtures. If not on the same dimmer, you might want to have a supply of R3204 and R3208 for the higher wattage fixtures run at a lower level, to counteract amber-drift.

The phasing in of a new lamp (style or wattage) is always a difficult process. It seems they always burn out when you don't want them to, but when you're waiting for old lamps to die, it seems to take forever. Develop a system of labeling or color-coding, not on the fixture but ideally on the lamp cap itself, so everyone immediately knows what wattage of lamp is in every fixture.

[DaveySimps]

You should definately consider upgrading to the 575W lamps. The additional power would make a big difference in light quality. As mentioned before, be sure to do it in stragitic groups so you are not fighting different quality of light from the same light position.

~Dave

[Grog12]

Originally Posted by JustAShadow

It would depend on how far your hang positions are from your stage, and how many fixtures are in your inventory. if your fixtures are lower than 20' above the deck and less than 25' horizontally, I would say keep the 375w. but if you are throwing farther than that, I would bump to the 575w as budget allows.

As a designer I'm not a fan of either the 375w or the long life 575w. I like the punch and the color tempature of the regular 575's. I like to use 750's in my PAR's and PARNel's.

This is regardless of distance. I really only like using 375's when I'm strapped for dimmers, and even then I don't "like" doing it.

From a ME/Budget standpoint I'm all about the 575 long life's, especially in my current theatre where I don't have 24hour access to a genie.

If you have the cash and can I'd bump to a 575 variety.

[waynehoskins]

Yep, 575 all the way. I'm lighting Grease at the high school now (well, goes up tomorrow), and today I ended up running out to rent a few S4s for the downstage frontlight system (to replace the blasted 1KLs). They've got 575s, but I really could do with 750s. I've got them running at 80-plus most of the time, but because of throw distance and all, even the 575s have a hard time punching through the KW-lamped Fresnel systems upstage and overhead. Shiny floor doesn't help at all.

No way would 375s be enough in this case, and they're 26s not throwing inordinately far, and the color in them is R62, so it's not too killer (all of 50-some percent transmissive). I might could have gotten by with 375s in the last show I lit, where I had R09 as the front. The 09 being 75%T, it might have been visible with 375s, maybe.

The S4s at 575 are at least a good point brighter than the KLs at 575, but that's an other topic.

[quarterfront]

+1 on the 575 longlifes gafftaper mentioned. Re Grog12's comment, it's true that the CT is a bit warm, but you get hours out of 'em and lifetime is money, which makes it a good compromise, at least where I live.

You'll want the extra output. I'd go for it.

[Grog12]

quarter- Read my post again and you'll see that I too agree with gaff...from a Technician standpoint.

As someone who toes the line, I have two views about most things. What's best for the production and what's best for the space.

Like I said before, as a designer (and there for for the production) the color tempature on the long lifes just sucks in comparison.

As a technician who has limited access to genie's or a ladder much less my own lightinhg equpiment hung in the air, the long lifes make more sense.

Neither answer is correct, as the world is not black and white.

For now (until I get this place up to my standards) the long life is the right choice for me. Once I get to a point where I can up the production values another step, that will no longer be true. Be cause better production values will benefit not only the productions but the space. Right now choosing the higher color temp would hinder both.

And that...has been 10 seconds in Grog's mind...brought to you by a lack of sleep and caffine.

[quarterfront]

Originally Posted by Grog12

quarter- Read my post again and you'll see that I too agree with gaff...from a Technician standpoint.

Yup, I was skimming instead of reading.

Sounds like you're in about the same boat as me. I'm a designer in tech, an ME during the run. I do have catwalks to get to pretty much all of my units, but I have to do the labor changing lamps out on a daily basis. And, too, budget's tight. OTOH, my director wants things bright bright bright most of the time. I end up putting 750's in my iCues as specials, and run the rest of my S-4's with longlife 575's.

Of course, the bulk of my inventory is Colortran 20/30/40's which run FEL's. that's a whole other story....