Probably 3.5x the lumens and 70% the throw of GT70. 20,000 lumens and 500k lux?
Now I’m kinda interested in this host with 4 SBT90 gen 2.
This discussion is incredibly interesting, please continue with scientific evidence, beamshots and other comparisons to support each theory!
Regardless, I am a bit disappointed as I was highly anticipating 1800m throw at minimum, to match the R90TS. I figured 4 large reflectors should throw better than 18 small ones…
Perhaps the R90TS which has 1800m throw at 36k lumens according to Vinh Nguyen’s measurements may shed some scientific light on this debate?
So by this logic a C8F will out throw a single C8 of the same LED type?
I think we just need 4 C8’s being held side by side/taped together, next to a single C8, pointed at the same white wall at the outer limits of the single C8. Then just see if there is any noticeable increase in the throw of the 4 C8’s taped together.
Yes, 4 C8s taped together will outthrow a single C8. Lux is nearly linear with output increase, but actual throw is not linear with lux.
If this wasn’t true, then people wouldn’t be making multi-reflector lights like the R90TS or this GT4.
It’s the ratio of the reflector to die size that is important. The R90TS uses really small xhp35-HI leds which are about 1/5 the size of the xhp70.2 with it’s dome on.
The GT4 reflectors are bigger than the R90TS reflectors, but are not 5 times bigger. So the 70.2 emitter is just too big for throw as good as the R90TS. A sliced dome 70.2 would be better to maximize throw, but that requires slicing the dome by hand which is difficult.
See post 694 and 695.
When you have a 70.2 making 5000 lumen in a C8 reflector it’s throw distance is way lower than the same emitter in a big GT reflector (maybe 500 meters?). If you add a 2nd 5000 lumen 70.2 with a C8 reflector and overlap the hot spots the throw distance increases. Add a 3rd and the distance increases more. Add a 4th and the throw distance increases again. I hope that 4 leds and reflectors will add up to about 1500 meters. I don’t really know. We will have to wait and see the actual measurements.
EDIT: I think we would need 750 meters from a single 70.2 and small reflector to get 1500 meters from 4 of them.
I know 4 C8 reflectors can fit in the bezel of the GT, but the actual reflector design in the GT4 is a bigger diameter than the C8 with 2 sides sliced partially off. Can one of those reflectors and a 70.2 do 750 meters? IDK.
Of course throw increases. Your math shows the candela increases 4 times. That is equivalent to double the throw in meters. It’s not 4 x the distance, but just double the distance.
You said the throw would not increase. I was contradicting you by saying yes, it would increase.
Maybe you can change “No, you won’t” to “Yes, it will”. I obviously have no idea what your saying. Sorry.
I wonder if the GT4 will come out before people start taping 4 C8s together…
Adhara, why are you being rude? There’s no need for that. I’m just trying to help out.
The way you worded your response to Xenovora was a bit strange.
I don’t even understand the programming comment. Is that another rude joke? It’s uncalled for.
I can’t remember if we already talked about it, but what is the deal with the battery carrier? Is it still 6 volt?
Are they just trying to get rid of the weak areas to allow for more current?
I see these are pics from TA.
Still a 2S carrier.
And yes, as at the time, the springs weren’t up to snuff with the current capabilities of 8x18650s and draw of 4x XHP70.2s.
I think the reflector design is more complex than 4 C8’s. It looks like while there is 4 the are not completely seperate. Wouldn’t this technically increase the size of each reflector? I’d imagine this wouldn’t be significant, but I’m sure it would have an effect.
Yes, the diameters are bigger than that of a C8. That is why I said this earlier.
I think the end result of 4 bigger reflectors sliced to meet together is more throw compared to 4 smaller, complete reflectors. I have not seen much study of this. It would be interesting to learn more about this reflector design theory.
I was just thinking the same thing today. With the SBT90 gen 2 that Acebeam is using in the K75, the GT4 might be able to get 20k+ lumens and 1.2MCD throw making it a R90TS killer and in a much better host. I really think Lumintop should consider this emitter otherwise the GT4 being so late to the game will not be very attractive since competing offerings from other manufacturers are already available.
I think it would throw more, yes. At the end of the day it’s all about reflective surface area against emitter area ratio. Spliced reflectors butted up against each can cram more surface area into the same circular head than individual wells. The tradeoff is you get flower petals.
This.