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Buyer's remorse: Can I use a 1K Tungsten Fresnel as a PAR?

Fresnel open face remove lens

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#1 Logan M. LeBlanc

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Posted 05 June 2015 - 01:43 PM

I purchased a Chinese Arri knock-off and while the output is decent with the lens, I think I'd benefit more from the light if I could use it as a lensless open-face.

My questions are: A) Is this safe/doable and B) How would I adapt this safely?

Thanks

 

The light: http://www.amazon.co...s=1000w fresnel


Edited by Logan M. LeBlanc, 05 June 2015 - 01:48 PM.

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#2 Brian Drysdale

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Posted 05 June 2015 - 01:56 PM

Fresnel lights are much more controllable than open faced lights, so are more versatile, lighting is much than just the light output..

 

You need some form of safety glass or mesh with open faced lights, an exploding lamp can cause injury or possibly a fire.


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#3 Logan M. LeBlanc

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Posted 05 June 2015 - 03:35 PM

Thanks for the reply Brian. Can you think of any mesh/glass one could pop in/out as needed? We're pretty run-n-gun so bouncing this into the ceiling w/o the lens is what I'm aiming to do.

 


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#4 JD Hartman

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Posted 05 June 2015 - 03:38 PM

Fresnel lights are much more controllable than open faced lights, so are more versatile, lighting is much than just the light output..

 

You need some form of safety glass or mesh with open faced lights, an exploding lamp can cause injury or possibly a fire.

 

Open face lights are more light efficient.  However, being it's just a 1K, I'd stick with the Fresnel.

 

Yes, safety wire on an open face is the norm, but regarding the exploding globe statement.  I've had and seen distorted globes in fixtures usually from contamination, but never have witnessed an "explosion",  Has anyone here?

 

No, once you swing open the door (max light output, max. spread) on a Fresnel you loose the ears, so really no way of dropping in a safety wire.


Edited by JD Hartman, 05 June 2015 - 03:40 PM.

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#5 Brian Drysdale

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Posted 05 June 2015 - 03:47 PM

I've had lamps "explode" on a few occasions. Redheads mostly, with small LTM Peppers being the other examples.

 

It's also happened a few times on live television (news programmes generally). mostly a loud bang.


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#6 JD Hartman

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Posted 05 June 2015 - 04:54 PM

What did they (the globes) look like?  Were little more than fragments left behind or did the globe have an area with a noticeable bulge?


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#7 ian dart

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Posted 05 June 2015 - 06:46 PM

i have had a few globes let go over the years, mostly in open faced lights, they just disintegrate and leave a bit of the base

and two pins in the lamp

i have never discovered the reason.

 

i had a 150 dedo globe explode on set during a take and that certainly woke everybody up

it cracked the mirror and scratched the focusing lens, i had it checked out but no one could

come up with an explanation.

 

my advice would be always have a safety screen on open faced lights.

 

cheers


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#8 Brian Drysdale

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Posted 06 June 2015 - 02:10 AM

They explode into bits, I've seen one land on the carpet from open faced light that didn't have a safety screen fitted.

 

 

 


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#9 David Landau

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Posted 14 June 2015 - 09:00 PM

I've had lamps explode, rarely but it has happened. Its usually an open-faced unit and its from either fingers touching the lamp - thus creating a bulge that bursts, or something else falling into the lamp envelope - dust, paint, moisture in the air, etc.

 

Bouncing the Fresnel with the lens will actually give you more light than using the unit without the lens. A Fresnel is designed different than an open-faced unit - the positioning and shape of the reflector is different. A Fresnel is designed to direct as much light into the center of the lens, while an -open faced unit is designed to direct light out of the entire opening.  Since the Fresnel concentrates the beam of light it achieves a higher output in a more limited spread, thus you can direct the bounce easier to where you might want it.  Using it without a lens is not safe nor very professional looking to your client/producer.  


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