Mateminco MT35vn90 - Best Ultra Thrower Value R

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SKV89

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Re: Mateminco MT90vn - Best Ultra Thrower Value R

De-lens makes it noticeably less green right?
 
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Re: Mateminco MT90vn - Best Ultra Thrower Value R

I saw it mentioned by a member in one of the forums that the Delens-ing increased throw by 13% and increased lumens by 14% (my calculations from his numbers). While I was willing to wait for more information, from an optical standpoint, borosilicate glass in that thickness should only see an 6-8% loss in transmission loss and that's making the assumption it's borosilicate. In any case, I think those gains are overly optimistic and should be more thoroughly tested. Vinh posted more conservative numbers which made a lot more sense.

With regards to tint shift, it's unlikely that a single, optically coated window is causing significant levels of shift and more likely that it's just the LED and the current level at which it's being driven, or the tint lotteries which we know happen. Perhaps latter versions of the SBT90 will shift less at different currents. I'm guessing that if Vinh tested the same light with and without the window, both would show nearly identical tint. This LED doesn't have any green when it's being driven hard.
 
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vinhnguyen54

vinhnguyen54

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Re: Mateminco MT90vn - Best Ultra Thrower Value R

Maybe luck of the draw? The difference between my two sbt90.2 lights are pretty dramatic.

Yup there is always the tint lottery too
 
vinhnguyen54

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Re: Mateminco MT90vn - Best Ultra Thrower Value R

De-lens makes it noticeably less green right?

I cant say for sure...If there is a diff its likely small.
 
vinhnguyen54

vinhnguyen54

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Re: Mateminco MT90vn - Best Ultra Thrower Value R

I saw it mentioned by a member in one of the forums that the Delens-ing increased throw by 13% and increased lumens by 14% (my calculations from his numbers). While I was willing to wait for more information, from an optical standpoint, borosilicate glass in that thickness should only see an 6-8% loss in transmission loss and that's making the assumption it's borosilicate. In any case, I think those gains are overly optimistic and should be more thoroughly tested. When Vinh posted more conservative numbers which make a lot more sense.

With regards to tint shift, it's unlikely that a single, optically coated window is causing significant levels of shift and more likely that it's just the LED and the current level at which it's being driven, or the tint lotteries which we know happen. Perhaps latter versions of the SBT90 will shift less at different currents. I'm guessing that if Vinh tested the same light with and without the window, both would show nearly identical tint. This LED doesn't have any green when it's being driven hard.


13/14 sounds steep...but who knows I have only tested a couple of samples so its hard to say. Next time I mod another SBT90 light I will measure before and after delens so we can have more data point. The good news is it seems just as reliable without the lens and there is an increased in performance. Free lumen I guess....
 
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Th558

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Re: Mateminco MT90vn - Best Ultra Thrower Value R

Someone measured an output increase of 9.8% after removing the LED lens in a different light.
 
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Re: Mateminco MT90vn - Best Ultra Thrower Value R

Someone measured an output increase of 9.8% after removing the LED lens in a different light.


It's nice to see other people measuring their results, though it really sounds optimistic. I don't discount them however without knowing the whole story or the reliability of the person making the claims. Vinh posted some resent results for a K65GT in the SBT90 thread which I just copied and pasted below. It seems to confirm his initial findings in the 3% territory. I'm sure that of all people he'd love to announce even higher gains but it just hasn't been the case. I don't know of anyone who actually measures more lights than Vinh, so I've really come to appreciate his consistency.

"Measured @ 2s
K65GT 5350L 844Kcd
K65GT + DeLens Only 5500L 884Kcd

2.8% Lumen Gain
4.7% Kcd Gain"
 
wolfstyle

wolfstyle

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Re: Mateminco MT90vn - Best Ultra Thrower Value R

Vinh do you plans on building and testing the delens SBT90.2 in this light?
 

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