Led positioning in TIR lens

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galenlai
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Led positioning in TIR lens

Anyone knows what is the effect if I shave off the mounting base of the TIR lens (or remove the gasket) and bring the led deeper into the lens?
Will the beam angle be narrower or wider?
Thanks in advance!

Scallywag
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I believe it will be wider, as demonstrated by zooming-TIR lights.

galenlai
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I don’t know.
But zooming lens is using convex lens.
I have a 25° optic lens.
Would it have the same effect or opposite?
I want it to produce a narrower beam.

Unheard
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Raising a LED in a reflector results in a finite focal point, so the beam gets narrower and then widens. Maybe similar with TIRs. But imo it only uglifies it.

Smile, you cannot kill them all.

jon_slider
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galenlai wrote:
I want it to produce a narrower beam.

I hope you find a way to get the result you seek

my guess is you will not see a meaningful change by altering the mounting height of the TiR

imo a more effective option would be to use a smaller throwier LED
here is an example of that
note the last couple of photos show the difference in beam throw

Unheard
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∆ this

Smile, you cannot kill them all.

galenlai
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Ok, thanks for all the advice.
Guess I will just stick to reflectors Big Smile

Henk4U2
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In general TIR lenses are made for specific led types. So positioning is (almost) perfect. My personal feeling is that TIR lenses cause less color artifacts like the fried egg image. The only thing that really changes the output is dedoming of the led. So in a way TIR lenses are less satisfying for people who like to tinker every part of the light. You might call it: good but a bit boring.

A big pro of a TIR lenses is that some types/sizes are available in a lot of varieties. Smooth, pebbled, haze, clear, stripes, etc. And with a lot of beam angles. From 10degr to 60degr. So if you want to make your light a bit throwier, put in a narrow beam TIR.

You are a flashaholic if you are forced to come out of the closet, to make room for more flashlights.

galenlai
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Ok. Thanks for all your feedback.
I will try to find a TIR lens with narrow angle.

sungar
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Most likely it would give you more spill and less defined hotspot. At least this is what I’ve observed playing with tir on xpl hi.

James C
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Somewhat related to the original question, different TIR types are more or less sensitive to modification. For example, I had to shave the base of a Convoy S2+ TIR to get it to fit in a Wowtac A6. The clear and pebbled TIRs all had ugly artifacts after shaving, but the frosted TIR I tied had no ill effects. This was with an SST 20.

In my fairly limited experience, I don’t believe you’ll get markedly different beam angles by modifying the TIRs or TIR-to-LED distance, but you can modify to address focusing issues (artifacts).