For wavien collars it doesnāt seem to matter much which size you use (if the LED is small). The luminance gain is almost the same (the small one is more difficult to focus though).
I finally remembered to calculate this. It was easier than I thought, all you need is Pythagorasās theorem for triangles since I already now the diameter of the reflector and the maximum focal length (94mm).
So the depth of the reflector is 73.2mm (distance from lens to focal point, straight down).
The real depth all the way to the bottom I donāt know yet, maybe an additional 15mm.
So, who is going to put a Black Flat into his BLF GT to try to beat this light?
sma tested the Osram Q8WP here (a source in China has surfaced) and unfortunately two of his only reached 190-206cd/mm^2 (same as the old XP-G2 R5/S2). It seems they are of the lowest possible Bin and thus very inefficient.
There is a different Osram LED though which has a higher luminance than the Osram Black Flat, the Osram Synios P2720 DMLN31.SG. This test showed that it can produce up to 297.8cd/mm^2, which is 20% more than the Black Flat. It's downside is that it only produces 200 lumens and the small Die creates a tiny spot (0.225mm^2). I think it's too small and dim for this light though. The Black Flat itself is rather dim...
Be more creative ;). https://www.yoycart.com/Product/547738518217/
Yoycart is a Taobao agent who has an English website showing which products he offers. This makes it much easier compared to buying on Taobao directly (only Chinese).
Huh, interesting.
How do we know that itās not an old Q9WP being sold as Q8WP?
If no reputable distributor like mouser or digikey have it, why would this site have it? https://octopart.com/search?q=UW+Q8WP
EDIT- I just found it available here actually, must have recently become available
Yeah, RS has the NAPA bin in stock, also the lowest, but whatās interesting is that there is a āV2ā version which is rated for 6000mA rather than the default 1400mA, even though it shows the same lumen values.
Maybe they just used the default lumen value from the datasheet but the LED can handle higher currents?
If they get some in stock I might buy one of each and compare them, but they will arrive in de cember so maybe by then we can find NBPB or higher bins.
They donāt mention āV2ā in the datasheet. RS has a new version of the datasheet for the V2 though, datasheet version 1.1.
There are a few differences. They removed the lowest Bin āNAā and added a new top bin āPBā. The maximum constant current ist still 5A (6A is for pulsed operation). There is also an example product code, where they used to list NA and now list the NB Bin. So I would guess that these new ones will be in NB Bin.
The problem here is that this isnāt enough. You will need at least the PA Bin to get any real benefit with this LED.
Generally itās very obvious that RS doesnāt do a good job of putting the real specifications into their database. The first Q8WP LEDs are specified as āthrough holeā components. :person_facepalming:
NAPA means it will be either NA, NB, or PA.
No idea which bin youāll end up getting when you purchase, since they just list the range of possible bins.
The only way to be certain youāre getting a high bin is to wait a loooong time until some places start selling PAPB or PBPB.
I know. Iām trying to say that you shouldnāt get your hopes up. Especially PBPB will probably never happen. I have never seen this with any of their LEDs.
Yeah, I know
I still plan to buy several of the Q8WPs when they become available to test them myself.
Probably get one or two from each of the product listings.
Do you know of any other potentially high intensity LEDs? the Lumileds one that djozz tested recently had really good thermal properties and efficiency, maybe something from that brand looks promising?