Luminit Holographic Diffusers

NH Lumens

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I've been experimenting with Luminit's holographic diffusion material cut and installed in several different Malkoff heads. The 5-degree pattern works really well to smooth the sharp edged rings and artifacts prevalent in the current heads using TIR lenses. Compared to improvised diffusion material such as window frosting film, the Luminit holographic material has a high VLT (visual transmission rate) of 90 percent.

Case Study: Wildcat

The current version of the Wildcat comes with a 10-degree diffuser, giving this head the flood pattern. Some have removed the diffuser to discover that the WC head actually has high candela, it's the diffuser which changes the beam pattern into flood. Without the diffuser, the WC head has all the rings and artifacts that are seen in the current Hound Dog head.

Replacing the 10-degree diffuser with a 5-degree pattern strikes a nice balance. I measure the candela with the 5-degree diffuser at about 20,000 making it comparable to the M91T head, but with a broader, smoother hot spot and brighter spill due to the WC's higher lumen output. I really like this combination.

Case Study: Hound Dog Super

I've always considered the HD Super as a specialty light. Though it has an incredibly wide beam pattern, the vast majority of the luminous flux is concentrated in the center of the beam.

diffusion-2.jpg
The diffusion lens is installed under the front protective lens with the textured side facing down towards the light source.

With a 5-degree diffusion lens installed, the luminous flux is spread out into a hot spot that is about twice as wide, with a smooth transition into its magnificent spill. Throw is cut approximately in half, but the "wall of light" the HD Super produces with the diffusion lens is impressive.

Case Study: E2XTD

I have a specialty light set up using the now-extinct E2XTD (650 lumen/70,000 cd), which produces a very narrow but extremely intense beam. I cut a lens to fit this head and the results were as expected: the cd was cut in half but the beam is wider and smoother with zero rings or artifacts. The head still produces about the same candela as the E2 Hyper Throw, but with a hot spot that is twice as wide, with a smoother transition to spill.

diffusion-3.jpg

Conclusion

Adding a 5-degree diffusion filter to a high-candela head will cut the throw in about half but approximately double the width the hot spot, smooth the transition to the spill and greatly improve the overall beam quality to near White Wall Hunting standards. If you're looking to take a "thrower" and tame the intense hot spot into something more useful, a diffusion lens could be the ticket.

diffusion-1.jpg

Additional information on these diffusion lenses can be found here.
 
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NH Lumens

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Interesting. Could be a useful application to reduce artifacts using TIR lenses? Is there a filter that does not reduce throw appreciably?

They are both directly related to each other: the more you smooth the beam via diffusion, the greater the reduction in luminous intensity (candela), regardless of the material used.

It's a matter of finding a happy medium. Malkoff supplies the current HD XPL with a 1-degree diffuser, which cleans up the beam slightly without a big hit on luminous intensity. The 10-degree diffuser used in the Wildcat completely smooths the beam and removes any trace of LED artifacts, but greatly reduces luminous intensity.

I've found the 5-degree material to provide that happy medium.
 

ilikeguns40

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I have some of this stuff from my wife's craft supplies. It's probably not as translucent as this stuff but it does the job if needed a Floody type light. I've found it fits perfect between the lens and bezel ring of the MDC heads and does not sacrifice water resistance if cut exactly a bit smaller than the o-ring but bigger than the bezel ring. Also protects the lens as an added bonus. Great to use indoors or up close tasks
IMG_9880.jpeg
IMG_9881.jpeg
 
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NH Lumens

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This review of the Hound Dog 18650 XT does a good job of showing the effect of the 1-degree and 5-degree diffusers (vs. no diffuser).


The current Wildcat is IMO a great candidate for the 5-degree version, producing 950 lumens and 20k (measured) candela. It's a very useful beam pattern, even on low.

WCMD2-1.jpg
 
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md17

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I just installed the 5 degree film in a hound dog xpl and m61hot and I like the results…

Hound dog stock 1 degree filter
IMG_5308.jpeg


Hound Dog 5 degree filter
IMG_5310.jpeg
 
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