Lumintop GT4

4 xhp70.2s in huge reflectors vs 9 xhp35 HIs in smaller reflector wells would be an interesting comparison. seems like the gt4 will make for slightly more lumen but slightly less throw.

Well, for one, it will have better QC, replaceable cells, non exaggerated specs, NarsilM.

And where did you find an R90C for 200$US?

The lowest price I’ve found with a coupon is 280$US.

It will be more reliable than the R90C specially at the driver, step down is user-controlled, probably brighter, much better heatsinking, and most likely without the fogging issues of immalent lights.

Sadly max output will drop accordingly to the battery level, being a direct drive setup.

And can be used with 8 18650s for much better runtime.

And you can get the light in Neutral White rather than Cool White.

This light was first planned WAY back when the GT was still in the planning stages. Needless to say things have progressed since then and it is not quite as revolutionary now as it would of been 2 years ago.

At this point, yeah there are other lights that would be direct competition for sure. How they would compare is something I can’t know without some testing though.

Lumintop finally said they want to proceed with this project and I was sure not going to say no lol.

Based on VOB’s lumen readings from the R90C though, I do expect higher lumen output from the GT4. My goal is ~20k real lumens or more.

Imagine 4 CFT90 in this thing. Power draw and cost would be unrealistically high.

4 2mm white flats would be nice as well.

Sure.I’ve got it at $290.00 .

CFT90’s would be awesome for the throw but the power draw (and light output) would be a bit less.

I wonder how much the head weighs? it must be alot more then normal gts as it looks quite beefy in the pics. So a runtime on highest should be like 5min atleast or so based on how it looks ?

If it has good runtimes on highest then it can compete with olights and acebeams monster lights then if the price isnt too high also.

It is not extremely chunky inside the head, a lot of volume is converted into finning, but fins have mass also of course, so yes, the head has a bit more volume and will be heavier than the GT. I’m really curious about what the sustainable light level will be actually, large flashlights have an unfavorable volume/surface-area ratio so scaling the power up from a smaller light requires disproportionate measures to create extra surface area (=fins). This is attempted in the GT4 but how the final sustainable output proves to be is a surprise. I hope for over 10K lumen with the head kept under 60 degC. (that will drain the batteries in say 45 minutes, so sustainable is relative :slight_smile: )

Classic lumens/thrower with more emphasis on the lumens (XHP70.2's). The Shocker had C8 size reflectors, looks roughly these are about the same size - Shocker had a smaller head diameter with 3 cups. Of course XHP70.2's can't compete even with a XM-L2 in throw, but maybe are closer when driven harder, and in the stock configuration, should beat a Shocker in throw for sure mainly because of the FET based driver and high amps.

I can’t wait to see some numbers on this bad boy, and hopefully it has a nice clean pedal free hotspot.

I think Dale, did a XHP70 mod to the Shocker - would be interesting to see what #'s it got.

Post here: https://budgetlightforum.com/t/-/33156/16, but no throw #'s.

It is about time for extra battery tubes. Those 70.2s will be hungry!

8x18650 is a plenty of battery power :slight_smile: For the GT/GT70 I think it was more of a too much,4x18650 would be good too,but for GT4 8x is enough

Interested!

I think XHP35 in GT is at or just under 150 cd/mm². Well cooled white flat is over 300 at peak, a little less in a regular fat host like GT. Boost HX should be even more intense. So… 75% higher LED intensity, 260 cd/mm²?

You would have to lose 43% elsewhere to end up with equal throw. What are the losses elsewhere?
Area loss. Not that high with a siamesed 7-up, especially that you can make the reflector cups very deep.
You may also lose a bit of throw by worse centering.

Am I missing something?

Nope you are not missing anything, your numbers sound good to me but I always under-promise and underestimate when possible.

which emitter is the white flat?

Osram KW CSLNM1.TG.