Lumintop BLF GTvn - Best Reflector Thrower?

Status
Not open for further replies.

UrbanExplorer

Newly Enlightened
Joined
Feb 16, 2017
Messages
39
Location
California.
Re: Lumintop GTvn - Best Reflector Thrower?

Gotcha my struggle was the overlapping of light. I tried calculating it based on how the light that is reflected off the reflector + spill calculated based on opening angle etc. I also tried using Lambert’s cosine law to find the cd or flux at every angle but I could never even get a confirmation on whether this formula was even applicable in this situation as lambertian emission is more tricky than reflection. Doesn’t help that my calc knowledge is extremely limited lmao. Is there a way I could learn more about this either from you or some helpful sources you could recommend? There is very little info that I can find on this topic. I find it odd that people are claiming all your info is wrong despite the effort put into the calculations.
 

noboneshotdog

Flashlight Enthusiast
Joined
May 28, 2012
Messages
1,351
Re: Lumintop GTvn - Best Reflector Thrower?

Gotcha my struggle was the overlapping of light. I tried calculating it based on how the light that is reflected off the reflector + spill calculated based on opening angle etc. I also tried using Lambert’s cosine law to find the cd or flux at every angle but I could never even get a confirmation on whether this formula was even applicable in this situation as lambertian emission is more tricky than reflection. Doesn’t help that my calc knowledge is extremely limited lmao. Is there a way I could learn more about this either from you or some helpful sources you could recommend? There is very little info that I can find on this topic. I find it odd that people are claiming all your info is wrong despite the effort put into the calculations.

I have only been hearing praise for all of Endermans work. Who is claiming his info is wrong. Nobody over hear that I can think of. Did I miss something...
 

Enderman

Enlightened
Joined
Nov 3, 2016
Messages
333
Location
Vancouver, Canada
Re: Lumintop GTvn - Best Reflector Thrower?

didnt know you spoke Chinese enderman? :confused:

cause thats what it looks like to me trying to read what you just wrote.:ironic:

care to translate that ? LOL !

course , im just a dumb ole country boy that likes bright flashlights:D
Haha, It's a bit hard to explain in a simple way :p
Maybe think about it as adding up the intensity of the light from all points around the LED.
Then you can just add up certain parts and divide by the total amount to determine how much of the total light is going to those parts :)

Gotcha my struggle was the overlapping of light. I tried calculating it based on how the light that is reflected off the reflector + spill calculated based on opening angle etc. I also tried using Lambert’s cosine law to find the cd or flux at every angle but I could never even get a confirmation on whether this formula was even applicable in this situation as lambertian emission is more tricky than reflection. Doesn’t help that my calc knowledge is extremely limited lmao. Is there a way I could learn more about this either from you or some helpful sources you could recommend? There is very little info that I can find on this topic. I find it odd that people are claiming all your info is wrong despite the effort put into the calculations.
I don't think anyone claimed my info was wrong, just a few people at the beginning of the thread that didn't know I had calculated this stuff already! haha
I'll PM you a few links that have some more information on this kind of stuff.
 

UrbanExplorer

Newly Enlightened
Joined
Feb 16, 2017
Messages
39
Location
California.
Re: Lumintop GTvn - Best Reflector Thrower?

Yeah enderman was right just a few folks at the beginning of the thread. Hell I don’t even know if they were aimed specifically at him.
 

UrbanExplorer

Newly Enlightened
Joined
Feb 16, 2017
Messages
39
Location
California.
Re: Lumintop GTvn - Best Reflector Thrower?

Ohhhhhhhh okay that makes sense. But figuring out the different luminous intensities of an LED in every single decision sounds awfully hard to do with just an LED spec sheet or even a measuring tool. After you get that measurement I’m assuming you somehow gotta define a bunch of not so clear cut areas to divide it up into in order to assign each a candela value. Finally I guess one can deduct from that the quantity of light that escapes the reflector and the quantity that hits the reflector. But that still doesn’t calculate the intensities or lux of the multiple rings u see in a flashlight beam pattern. Also aren’t hemispherical LED’s isotopic in emission? Or do candela or luminous flux (or both???) go down with the angle? I’ve heard LED’s are lambertian sources but idk if that applies to flat LED’s domed LED’s both etc.
 

Alex1234

Flashlight Enthusiast
Joined
Jan 23, 2010
Messages
3,982
Location
Bear Delaware
Re: Lumintop GTvn - Best Reflector Thrower?

man, no love for the mighty GT lately i see....:shakehead

Its going to take a few months to get this driver perfected. Long wait but it will be worth it in the end. This led is a different animal then were use to. It demands respect. Lol
 

Newlumen

Flashlight Enthusiast
Joined
Feb 12, 2016
Messages
4,389
Location
United States
Re: Lumintop GTvn - Best Reflector Thrower?

So yea. One guy was testing the stock blf gt and can lift up the cargo containers from. 1.7 miles. ( 2700 meters). Thats crazy.
 

Enderman

Enlightened
Joined
Nov 3, 2016
Messages
333
Location
Vancouver, Canada
Re: Lumintop GTvn - Best Reflector Thrower?

Man...INSANE..How much for this?
I would guess $500-1000 Since he makes almost no profit if it's less than $500.
Also it's hard to get a GT at the moment since the group buy is over and the manufacturer hasn't started selling them retail yet.
Plus it will be one of the farthest throwing LED+reflector flashlights in the world, with a lot of lumens to go with it too which is different from the typical low-lumen aspheric throwers.
So IMO a $1000 price tag would be justified, but we'll have to wait for vinh to tell us the actual price.
 

vinhnguyen54

Flashaholic
Joined
Sep 14, 2010
Messages
25,242
Re: Lumintop GTvn - Best Reflector Thrower?

CFT90 version wont be ready until 2-3 months.
I might just try an oslon version now just for kick! hahah
 

giorgoskok

Newly Enlightened
Joined
Nov 6, 2015
Messages
46
Re: Lumintop GTvn - Best Reflector Thrower?

CFT90 version wont be ready until 2-3 months.
I might just try an oslon version now just for kick! hahah

Stock driver can be modded to work with 3V leds . I think Texas Ace from BLF is already testing it .
 

Issue

Enlightened
Joined
May 9, 2013
Messages
269
Location
Sweden
Re: Lumintop GTvn - Best Reflector Thrower?

Is this light made my lumintop togheter with BLF and will be sold my lumintop soon? Im a bit confused. :)
 

Issue

Enlightened
Joined
May 9, 2013
Messages
269
Location
Sweden
Re: Lumintop GTvn - Best Reflector Thrower?

Correct. I have one for sale if interested. Pm me for details

For me, this light is to big for current specs. The tn42vn will beat it, in a much smaller format. But if Vinh can do some magic with it i dont think i can resist. :)
 

Enderman

Enlightened
Joined
Nov 3, 2016
Messages
333
Location
Vancouver, Canada
Re: Lumintop GTvn - Best Reflector Thrower?

For me, this light is to big for current specs. The tn42vn will beat it, in a much smaller format. But if Vinh can do some magic with it i dont think i can resist. :)
If you put the same LED in the TN42 and the GT, the GT will always outperform it in terms of throw by almost 2x cd.
That's just how the physics work.
 

Issue

Enlightened
Joined
May 9, 2013
Messages
269
Location
Sweden
Re: Lumintop GTvn - Best Reflector Thrower?

If you put the same LED in the TN42 and the GT, the GT will always outperform it in terms of throw by almost 2x cd.
That's just how the physics work.

Dont get me wrong. It was just a replay to the offer of buying a stock version. Even if its slightly better than tn42vn, it does not weigh up for the size increase. But if vinh manage to mod both i will probably put my money on this light, if i can afford it.
 
Status
Not open for further replies.
Top