I really need some advice.

[derekleffew]

[user]shiben[/user] and I are saying the same thing. The difference is he is willing to compromise (lower) the angle of elevation to accommodate the photometrics of the frontlight (only) fixtures. Without a careful study and more information, I'm not sure I'd do that. But maybe I would. Lighting is all about knowing when/where to compromise and when/where to stand one's ground. ("No, Mr. Artist's Representative, I WILL NOT randomly fire all the strobes during the ballad." "Oh, you're threatening my paycheck? Well then, here you go! <strobe> <flash> <bang> <bang>. What do I care?--I'm only the lighting guy." )

...To get a beam size, do the same thing, but make a cone with the pointy bit the angle of the instrument (beam angle is the one you want, I believe, correct if wrong), and line the axis of the cone on the throw distance. ...

You are correct. In a perfect world with perfect lights, beam angle and field angle would be exactly the same. But since it's not, using the calculations for the smaller of the two, beam angle, gives you some wiggle room, and ERS have shutters don't they? Easier to make the pool smaller than larger, exactly what [USER]misterd[/USER] is currently confronted with.

...Often, manufacturers will give data on the photometrics of their instruments either on the Web or in print form somewhere. ...

[USER]misterd[/USER], tell us the model number of your fixtures, and I'll post the cut sheet which contains all this information.

 

[shiben]

You are correct. In a perfect world with perfect lights, beam angle and field angle would be exactly the same. But since it's not, using the calculations for the smaller of the two, beam angle, gives you some wiggle room, and ERS have shutters don't they? Easier to make the pool smaller than larger, exactly what misterd is currently confronted with.

Now heres the question that I have on a similar topic (so a minor hijack but one that Mr. Leffew should be able to clear up rapidly), is the degree indication on say a Source 4 the beam angle, field angle, some sort of average, or a close aproximation of the YxZ's actual resultant angle? On VW, measuring the angle on a "40º LekoLight" actually gives a 37.61º field and a 27.15º beam. So how do they get 40º, as 36º would be a better aproximation, would it not?

 

[derekleffew]

...On VW, measuring the angle on a "40º LekoLight" actually gives a 37.61º field and a 27.15º beam. So how do they get 40º, as 36º would be a better approximation, would it not?

Well, yes it would, but they (Strand) simply rounded up. Note that the "40º LekoLight" series came immediately after the line that misterd has, and was Strand's first departure into degrees rather than 6x9, 6x12, and so on.
A similar question is "Why do Source Fours come in 19, 26, 36? Why not nice round numbers: 20, 30, 40?"*

Note the ETC Source Four's names and actuals:
Name: - Beam/Field: - Old Style
5° - 6/7
10° - 8/11
14° - 14/15
19° - 15/18 - 6x16
26° - 18/25 - 6x12
36° - 27/34 - 6x9
50° - 36/50 - 4.5x6.5
70° - 60/70
90° - 79/87
The beam/field angles are measurements (with a light meter and protractors) from an actual representative fixture, and are according to the latest version of each cut sheet. The numbers vary slightly depending on the date of the cut sheet.

*Conveniently, and maybe even intentionally, the Source Four sizes approximated those of the Altman 360Q--the most-used fixture prior to 1992.

 

[misterd]

WOW. Thank you for the detailed responses! I'm learning a lot from all of you. Thank you so much.

Here is some more info:
The lenses on the Strands are 6x16.
The stage isn't as difficult to move as you're probably thinking (requires several guys to pick it up and shift it back).
The stage can (and will) be moved 10' back.
Buying between 2 and 4 new instruments with 6x12 lenses (or larger) is now an option, as long as the price is right (about $100 or less each is the goal).

I know I need to supply you with more measurements, but unfortunately I read your awesome and thoughtful posts after I left the theatre.

Anyways, I'm going to ask a few more questions, knowing that the answer may very well be impossible to give without said measurements:
Will moving the stage 10' back make a significant improvement in beam diameter?
Will getting between 2 and 4 lights with 6x12 lenses (or wider) help my cause?
If so, should those instruments be ellipsoidal reflectors as well?

Thanks again, friends. I feel like I should be paying you or buying you lunch for all the wonderful advice you're giving me!

 

[derekleffew]

...The lenses on the Strands are 6x16. ...

I was afraid it might be something like that.

...Will moving the stage 10' back make a significant improvement in beam diameter?...

It will, but your angle of elevation will be severely flattened. No way to overcome the "deer in headlights" look. What we most need to know is the height above the actor's head of the fixture mounting position (or the ceiling height from the audience floor). The short answer is that 6x16s are virtually unusable in the space. (They're fine fixtures, but much more suitable for throws of 30'-50'. *)
I'd rather have 10x 6" Fresnels.

-----
Since I promised, here is the back of the original 1979 cut sheet:


*The most important information on the page is Diameter = Distance X .40 which means that for 20' of throw distance you only get an 8' pool, on the floor. At +5' where the actor's face (arguably the most important part) is, it's only a ~6' pool. May be okay as a super bright special, but not when trying to wash the entire stage. No wonder the lighting looks spotty! No amount of diffusion will help that. Unless the ceiling is over 20', your most useful instruments will have a minumum Multiplication Factor of 1.0, which means a field angle ≥ 45°.

...Will getting between 2 and 4 lights with 6x12 lenses (or wider) help my cause?
If so, should those instruments be ellipsoidal reflectors as well? ...

You'll need maximum 6x9 fixtures. Mixing with 6x16s will cause issues.
ERS s are used for FOH applications because they produce less spill on the auditorium walls and ceiling than other fixtures. In a black box theatre, with short throws, Fresnels may be more useful, and less expensive.

I suspect your next question may be answered by Sources for Used Equipment .

 

[gafftapegreenia]

I'd rather have 10x 6" Fresnels.

I was totally just thinking the same thing! I've found the 6" Fresnel, in a Black Box type application, to be much more useful than an equal number of Ellipsoidal. Of course these days the Chinese PAR cans are so cheap most people choose those instead.

It's a shame used 4.5x6.5's aren't more common, but while 10 6x9's aren't ideal, they could be made to work.

 

[derekleffew]

...Thanks again, friends. I feel like I should be paying you or buying you lunch for all the wonderful advice you're giving me!

IF your location: "MW" is short for Milwaukee, I'm sure Greenia would let you buy him lunch. If it's not, perhaps post a more descriptive location and possibly another CB member could help you out.
Will light for food is not an uncommon phrase heard in our industry.

 

[JChenault]

In a perfect world with perfect lights, beam angle and field angle would be exactly the same. But since it's not, using the calculations for the smaller of the two, beam angle, gives you some wiggle room, and ERS have shutters don't they? Easier to make the pool smaller than larger, exactly what misterd is currently confronted with.

It depends on what kind of perfection you are looking for. I was taught that if you are trying to blend acting areas, you don't want a flat beam of light ( IE beam and field angles the same). Instead you want to pick fixtures and position them so the beam angles meet halfway between the acting areas. The field overlap fills in the light and smooths out the beams so that the light is more consistent as you move between areas. If the field as flat, you could not get an even wash. (Now if you are projecting Gobos, you usually do want a flat angle.)

Put another way, If I want a smooth wash I try to set things up so that:
The axis of the beam is pointing at the head of the actor in an Area.
The Beam Angle is between the two areas.
The Field angle hits the actors head in the next area.

How do others do it?

 

[derekleffew]

See A Practical Guide to Stage Lighting author Steve Shelley's "The Slinky Method of Calculating Focus."

 

[misterd]

Alright, thanks for clearing all that up everyone.

Now, what exactly do you all suggest I buy for optimal lighting?
Something like 4 fresnels and 4 6x9 Lekos, as well as a sheet of Rosco 119 for all Lekos?

Needless to say, money is not abundant, so I want to be able to light the stage well without destroying the budget.

Thanks guys. You keep amazing me with your thoughtful responses and advice.

 

[gafftapegreenia]

Alright, thanks for clearing all that up everyone.

Now, what exactly do you all suggest I buy for optimal lighting?
Something like 4 fresnels and 4 6x9 Lekos, as well as a sheet of Rosco 119 for all Lekos?

Needless to say, money is not abundant, so I want to be able to light the stage well without destroying the budget.

Thanks guys. You keep amazing me with your thoughtful responses and advice.

At this time I'd try to buy 10 6" Fresnel (Preferably the Altman 65Q which can be found used all over) and then keep your 6x16's to use as specials. The zoom range on the Fresnel in that size of a space will prove beneficial.

You really won't be happy with a mix of 4 6x9 and 4 Fresnel.

 

[misterd]

At this time I'd try to buy 10 6" Fresnel (Preferably the Altman 65Q which can be found used all over) and then keep your 6x16's to use as specials. The zoom range on the Fresnel in that size of a space will prove beneficial.

You really won't be happy with a mix of 4 6x9 and 4 Fresnel.

Okay. I would also like to do that, but I don't think spending $1500 is an option right now. What if I continued to use the 6x16s and added 5 PARs? Would that look good on stage?

 

[shiben]

Alright, thanks for clearing all that up everyone.

Now, what exactly do you all suggest I buy for optimal lighting?
Something like 4 fresnels and 4 6x9 Lekos, as well as a sheet of Rosco 119 for all Lekos?

Needless to say, money is not abundant, so I want to be able to light the stage well without destroying the budget.

Thanks guys. You keep amazing me with your thoughtful responses and advice.

At this time I'd try to buy 10 6" Fresnel (Preferably the Altman 65Q which can be found used all over) and then keep your 6x16's to use as specials. The zoom range on the Fresnel in that size of a space will prove beneficial.

You really won't be happy with a mix of 4 6x9 and 4 Fresnel.

I would try to buy 10 6" Fresnels right now, and use them as well. My NEXT purchase would be 6x9s or something, and then move to having 10 areas of frontlight and 10 areas of top light or backlight or some other light like that. I guess I would plan on it more being a long term investment if your going to be looking at a long term space?

 

[Les]

Okay. I would also like to do that, but I don't think spending $1500 is an option right now. What if I continued to use the 6x16s and added 5 PARs? Would that look good on stage?

Unfortunately not. The 6x16's will greatly out-punch the pars, adding to the hot spot issue.

Look around on eBay (if it's an option) for Altman 65Q and/or 6x9's. The Strand Leko's you have also turn up every once in a while -- perhaps you will find a suitable beam spread while keeping your instruments within the same vintage/series. Search keywords "Altman Light", "Ellipsoidal" and "Leko". I have had good luck with this in the past. Used lighting sites are pretty good also, if you want to go that route. The main difference is that the pro sites will know what they have and what it may need to operate safely and relaibly, however they also know what it's worth and need to make a profit. Ebay, on the other hand, is full of sellers who are motivated to move gear (sometimes cheaply) but you may get "surprises" when you receive said gear. I've had pretty good luck with eBay *squinting*, but you have to be careful. AVForSale on eBay often has good gear at reasonable prices, They are experienced in lighting equipment, thus very honest and descriptive of an item's condition.

I recently picked up these older Altman 6x9's from a a different eBay seller for about $60 each. They are in excellent condition.

 

[derekleffew]

...and added 5 PARs? Would that look good on stage?

While that is a great deal on 5 Thomas PAR64 cans, the included MFL lamps are not proper for your space.

We were all thinking something like this: GearSource - Used and New L&E 6" Fresnel .
Discuss with the owner: maybe try to sell the Strand 6x16s for $75-100 each, and buy Fresnels?

Where are you again? Perhaps you can find used lighting closer to you and save the shipping charges. Is there a friendly local lighting company in your area? They sometimes have great deals on used gear.





(Hey Noah, I bet you'd give your left nut to have this!)

 

[misterd]

Alright, I see. I agree that purchasing fresnels is a good long-term investment, I just hope it's a viable option financially.
I'm located about 45 minutes south of Chicago. I just called Grand Stage in Chicago and they quoted me at $127 each for Altman 65Qs-- quite a price difference from these fresnels from GearSource that Mr. Leffew suggested in his last post. Although they aren't the same 750w vs. 500w, brand name, et cetera-- I'm wondering if I could just get the fresnels that Mr. Leffew suggested and be fine.

Would the 10 GearSource fresnels look good onstage and provide adequate flexibility if I sold 5 of my current lekos and kept the other 5 for specials?

Once again, I don't have exact distances for you to go off of, but can you maybe give me a general idea if this will work out?

Thanks so much for your invaluable help. I would still be at the theatre blaming myself for not knowing how to focus the lekos if you guys weren't so selfless with your time and willing to share your knowledge with me.

 

[icewolf08]

I wouldn't sell what you have right now. At least at the moment you have something that shines light on the stage! The fresnels you linked to are cheaper for a couple reasons: A) They are used, B) The probably have a used lamp, C) they don't have clamps, safeties, or color frames. Now, you would have to check to see if lamp, clamp, color frame, connector, and safety are included in the price from Grand Stage. You could also have them quote you on the L&E fresnels, they are just as good Altman.

Here is something to consider, you don't want to end up with any fewer instruments than you have now. Right now we are talking small numbers of units, and you probably will need every one and still not really get the coverage that you want. What kind of shows are being produced in this space? What kind of dimming and control system do you have? These are all things to think about that could really help with how we can help you.

 

[misterd]

Oh, and one more quick question: will 10 500w fresnels be enough?

I'm just concerned about the wattage, as our current lekos are 1000w (and yes, the bulbs are also 1000w).

We are almost definitely going to purchase those (10) 500w fresnels from GearSource, I just want to know if there are any reasons why we shouldn't purchase them so I can make a more responsible judgement call.

Thanks again.

 

[shiben]

Oh, and one more quick question: will 10 500w fresnels be enough?

I'm just concerned about the wattage, as our current lekos are 1000w (and yes, the bulbs are also 1000w).

We are almost definitely going to purchase those (10) 500w fresnels from GearSource, I just want to know if there are any reasons why we shouldn't purchase them so I can make a more responsible judgement call.

Thanks again.

Buy them. I have used those a couple times, and I actually like them a lot. Just dont sell the rest of your instruments. Then, you can use them for other things. You would be supprised, sometimes you actually want a narrow beam in there, and if you can hang another pipe for another position, or add on to your other pipe with some really narrow specials. There are more times than I can count that I want a 10º in our 18' gridded black box theatre.

 

[kicknargel]

I agree that the fresnels will be great. Just to cloud the issue with one other option I haven't noticed mentioned--the Altman Baby Zoom. It goes as wide as 50deg, and is a good unit for smaller venues, especially with a GL(x) lamp. Not going to be a cheap as the fresnels, though.