Conventional Fixtures Light from a PAR can

[itie]

Hello everyone,

So I'm new to using par cans and have only used two brands. I'm not sure what brands but I know they were different. One was a par 58 and the other was a 64. The issue I am having is the light coming from them is rectangle. I spoke to a friend and he told me to turn the lamp. I haven't gotten on the ladder to test this but it doesn't sound like a good fix. Does any one else have this problem? Would turning the lamp really fix it?

Thank you
Giovanni Laucella

 

[techno89]

There are different types of floods for different types of lamps like narrow, flood, extra wide flood, etc.... make sure you are using the right lamp type, turing the lamp would make the "rectangle" you're seeing go either horizontal or vertical.

 

[JD]

Nature of the beast. The tighter the beam (VNSP, NSP), the more pronounced the effect is. Varies a bit from (lamp) brand to brand, you can usually find the specs at the manufacturer's site. Simply put, the filament is not a point source. Some lamps, like ACLs, coil the filaments near center and have a tighter beam spread, but ACLs are not 120 volt.

Just a matter of rotating the lamp to the axis that produces the least offensive beam for your application.

 

[Les]

Also, brand of par can won't matter as much as the brand of the lamp. A par lamp is, by all practical purposes, a lighting instrument in itself.

 

[icewolf08]

Hello everyone,

So I'm new to using par cans and have only used two brands. I'm not sure what brands but I know they were different. One was a par 58 and the other was a 64. The issue I am having is the light coming from them is rectangle. I spoke to a friend and he told me to turn the lamp. I haven't gotten on the ladder to test this but it doesn't sound like a good fix. Does any one else have this problem? Would turning the lamp really fix it?

Thank you
Giovanni Laucella

As mentioned, that is the nature of the PAR. Generally you only see this in PAR56's and PAR64's. The long axis of the light always runs in the same direction as the porcelain of the lamp base. By spinning the lamp in the fixture you can adjust where that long axis of light goes. This is commonly known as spinning the bottle. We end up with the oblong shape because the filament is long and horizontal as opposed to small and compact.

So, in reality, the oblong beam of light that you get from a PAR is not a problem, it is how they work. It is true that you may need a wider lamp for better coverage, but in general you just need to understand what the light is doing and how to work with it. Often this beam shape can be useful when creating washes.

 

[derekleffew]

If you desire a round beam from a PAR 56/64 you might try adding a directional silk diffusion media (Roscolux 104, Lee 228, GAM 65, Apollo 1150) with the lines running the same as the long axis. The result will be more like a square with very soft edges, not round, but it may get you the desired coverage.

 

[Grog12]

We end up with the oblong shape because the filament is long and horizontal as opposed to small and compact.

This actually isn't true, if it were then S4 PAR's wouldn't work the same way. Its actually the Parabolic Aluminized Reflector that is responsible for the shape.

 

[derekleffew]

We end up with the oblong shape because the filament is long and horizontal as opposed to small and compact.

This actually isn't true, if it were then S4 PAR's wouldn't work the same way. Its actually the Parabolic Aluminized Reflector that is responsible for the shape.

Some confusion here.

Any parabolic reflector will reflect parallel rays from a light source placed at its focus.

In the case of the PAR lamp, the linear filament is responsible for the oval beam produced:

Which is why all VNSP, NSP, MFL, WFL produce oval beams. The striations on the lens of the MFL and WFL exacerbate the effect.

In a Source Four PAR,

the VNSP and NSP lenses (top) produce round beams. Only the MFL and WFL lenses (bottom) are oval beam, again, due to the lenticular lens.

The XWFL (aka buxom) lens, with lines running both ways, produces a round beam.

-----

...One was a par 58 ...

PAR 56. That 1/4" [(2/8)"] in diameter matters, especially as there's no such lamp as a PAR 58.

 

[itie]

Thank you for the great info. Im reading this from my phone but will do a good read through later. I was thinking that it was because its a par can and they just do that. I'm looking to buy some source four pars, do they have the same issue?

Thank you
Giovanni Laucella

 

[Les]

I'm looking to buy some source four pars, do they have the same issue?

This will be answered as you do a more thorough read through. Try not to think of it as an issue, but as a feature. Well, unless you make it an issue .

 

[techieman33]

if you want a round light another option is installing a ray (raylight) kit and a dys lamp. You'll be limited to 600 watts though, and the life of a DYS is pretty short ~75-100 hours.

 

[Grog12]

I stand corrected.

 

[theILLUMINATEDfrog]

with all that being said, just go for a different instrument, like a Fresnel or S4 Parnel

 

[itie]

Wow thats why more info then I ever expected. Thank you everyone for the help. Glad to know that buying a source four par wouldn't solve my issue.

thank you
Giovanni Laucella

 

[icewolf08]

Wow thats why more info then I ever expected. Thank you everyone for the help. Glad to know that buying a source four par wouldn't solve my issue.

Just remember, it isn't an issue (per se), as it is a function of how a PAR fixture works. You may not like it, or it may not work for your design, but there is nothing wrong with the fixtures.

 

[JD]

PARs are great when you just need to dump buckets of light on something! They are inexpensive, quite efficient, and the whole optics system gets replaced every time you replace the lamp!

As Derek said, the beam can be somewhat reconfigured by adding diffusion, or extending the snoot. There are plenty of modified pars, such as using a Raylight with separate lamp and reflector, and improvements such as the S4 par. Of course, all of these things increase the price.

PARs really seemed to explode on the scene with touring rock bands, where you needed to have a lot of lightweight bang for the buck. These days, they have settled into a slightly more mature nitch:

Lots of light, inexpensive, efficient, in non-critical beam applications.

 

[MrsFooter]

PARs are great when you just need to dump buckets of light on something! They are inexpensive, quite efficient, and the whole optics system gets replaced every time you replace the lamp!

They're also fantastic when you don't necessarily get to genie focus every time. Half the time I'm bouncing my rig back into focus, and PARs are great because as long as you point them at the right quadrant of the stage they'll make a gorgeous, even wash. I just wouldn't necessarily use them as a special!

(Though now that I think on it, I've have a rock LD or two put a VN lense in them and use those as back/top specials for the band positions, they looked great. So I guess I was wrong there. Way to call myself out, me.)