[PART 1] Official BLF GT Group Buy thread. Group buy officially closed! Lights shipping.

Jerommel · 2018-01-09T05:32:22.000Z

If this represents the difference between the cool white and the neutral white XHP35 HI Dale has, my conclusion is the neutral white one is a much lower brightness bin or there’s some driver problem.
I wonder if they draw the same current.
Either way, the one is much brighter than the other.

JasonWW · 2018-01-09T05:33:41.000Z

Longtom:

I never “match” 18650s. I am an electronics technician, and I do this shit for a living. I just don’t care enough to go out of my way to get 10% more life out of an $8 investment. As long as it’s a quality high drain battery from a reputable manufacturer, such as Sony, Samsung, or LG, and doesn’t include “fest,” or “ultra,” in the name, (you know who you are) you’ll be just fine. when they wear out, I get more, or crack open a few more laptop battery packs.

Unlike cells in parallel, there is a serious safety issue involved when you run cells in series. If they are mismatched, then one could drain down to below a safe level before the low voltage protection kicks in. The lvp sees the combined voltage of all 4 cells so it doesn’t know if one is at 2.1 volts and the rest are at 3.3 volts. It will just see 12 volts total.

Then when you go to recharge this battery at 2.1 volts it could do all kinds of nasty things. Swell up, vent, produce flames, etc…

Someone correct me if I’m wrong.

teacher · 2018-01-09T05:37:44.000Z

ALABAMA

College Football National Champions
National Championship # 17
8 January 2018

Good game Georgia.
.
.
Back to our regularly scheduled programming & ramblings….

Jerommel · 2018-01-09T05:40:01.000Z

JasonWW:

Longtom:

I never “match” 18650s. I am an electronics technician, and I do this shit for a living. I just don’t care enough to go out of my way to get 10% more life out of an $8 investment. As long as it’s a quality high drain battery from a reputable manufacturer, such as Sony, Samsung, or LG, and doesn’t include “fest,” or “ultra,” in the name, (you know who you are) you’ll be just fine. when they wear out, I get more, or crack open a few more laptop battery packs.

Unlike cells in parallel, there is a serious safety issue involved when you run cells in series. If they are mismatched, then one could drain down to below a safe level before the low voltage protection kicks in. The lvp sees the combined voltage of all 4 cells so it doesn’t know if one is at 2.1 volts and the rest are at 3.3 volts. It will just see 12 volts total.

Then when you go to recharge this battery at 2.1 volts it could do all kinds of nasty things. Swell up, vent, produce flames, etc…

Someone correct me if I’m wrong.

Well, usually it’s not that dramatic.
But, in an absolute worst case scenario, the 3 good cells with 4.2 Volts could reverse charge a 0.0 Volts bad cell with 12.6 Volts.
Then it may indeed vent…

JasonWW · 2018-01-09T05:43:01.000Z

Jerommel:

JasonWW:

yclongthrow:

I noticed that the reflector on my GT has an orange peel to it, not the super smooth appearance of my other throwers. I hope that this didn’t result in too much lux decrease.

Aside from that this thing is great!

These are obviously not orange peel reflectors. They are machined from aluminum and there has to be a certain compromise between the time it takes to machine them and how smooth the finish is. They are not perfectly smooth.

Orange peel effect is possibly due to uneven aluminium deposition (the reflective layer).

No, it’s the machined grooves.

yclongthrow · 2018-01-09T05:51:23.000Z

teacher:

yclongthrow:

I noticed that the reflector on my GT has an orange peel to it, not the super smooth appearance of my other throwers. I hope that this didn’t result in too much lux decrease.

Aside from that this thing is great!

Any chance you could post a close up picture?

I believe you… but would just like to see it. .

I took a few pics which demonstrate it quite well. Can I email them to you or Facebook message them so you can post? I completely forgot how to post pictures. Thanks

Also I completely understand the cost aspect of perfect reflectors, this is after all budget light forum. The GT completely meets expectations.

yclongthrow · 2018-01-09T06:15:19.000Z

please look at resized images in Teacher’s post.

R10500 · 2018-01-09T06:03:58.000Z

If it does turn out that someone’s GT is flawed or malfunctioning, what will be the procedure for returns? I expect that we’ll probably have to contact Lumintop or perhaps Neal in that case but will we have to bear the cost of returning?

DENGOH · 2018-01-09T06:24:43.000Z

JasonWW:

Longtom:

I never “match” 18650s. I am an electronics technician, and I do this shit for a living. I just don’t care enough to go out of my way to get 10% more life out of an $8 investment. As long as it’s a quality high drain battery from a reputable manufacturer, such as Sony, Samsung, or LG, and doesn’t include “fest,” or “ultra,” in the name, (you know who you are) you’ll be just fine. when they wear out, I get more, or crack open a few more laptop battery packs.

Unlike cells in parallel, there is a serious safety issue involved when you run cells in series. If they are mismatched, then one could drain down to below a safe level before the low voltage protection kicks in. The lvp sees the combined voltage of all 4 cells so it doesn’t know if one is at 2.1 volts and the rest are at 3.3 volts. It will just see 12 volts total.

Then when you go to recharge this battery at 2.1 volts it could do all kinds of nasty things. Swell up, vent, produce flames, etc…

Someone correct me if I’m wrong.

Regarding safety, the danger is real. When battery is almost empty, and the other batteries are not, the empty battery will not be able to supply the current needed, and its voltage will fall below 0 and goes to negative volt region. It will heat up very fast. I guess explode or not will depends on quality of the battery. This was my experience with 4x 26650 batteries in series. I quickly took out batteries and measured the hot one to be negative volt. And it couldn’t be recovered by recharging it slowly. It would release the energy as heat, the battery was like shorted inside and it would not store energy but release the energy as heat.

Regarding recharging overdischarged battery, I don’t think you are wrong but there are many manufacturer for batteries.
My experience tell me that as long as you don’t discharge it below 0V, it is still recoverable. Two weeks ago I had one 26650 discharged to about 0.6v due to high standby current of my flashlight. I take it out and measured 0.6v, battery not hot, it slowly climbed up. The next day I measured it was 0.7v. So I start charging it with 500mA, my charger thought it is NiMH battery, but when it reach 1.5V is showed finish charging but jump to charging again as lithium battery. When it reached 3V, i set the charge current to 1A. And it continued to charge and stopped charging at 4.2V, charged capacity was around 3600mAh. The battery is unprotected INR26650 KingKong that I bought 4years ago. And I let it rest for 1 week, last night I measured the voltage at 4.16V, not hot on battery body, not bad at all. Of course i had other overdischarging battery experiences, but this one is the freshest one.

yclongthrow · 2018-01-09T06:07:00.000Z

I apologize for the huge images. What should I resize them to?

As far as the machining lines being the cause I’m not sure if that’s the case. My C8 has machining lines but the reflector is still smooth. Same with my old school throwers like fandyfire with 50ish mm reflector.

The GT reflector has lines in addition to what appears to be uneven deposition.

I’ll wait for someone with more knowledge to chime in. Obviously the unprecedented size of the GT reflectors limits comparison to other reflectors to some degree.

teacher · 2018-01-09T06:07:29.000Z

yclongthrow:

teacher:

yclongthrow:

I noticed that the reflector on my GT has an orange peel to it, not the super smooth appearance of my other throwers. I hope that this didn’t result in too much lux decrease.

Aside from that this thing is great!

Any chance you could post a close up picture?

I believe you… but would just like to see it. .

I took a few pics which demonstrate it quite well. Can I email them to you or Facebook message them so you can post? I completely forgot how to post pictures. Thanks

Also I completely understand the cost aspect of perfect reflectors, this is after all budget light forum. The GT completely meets expectations.

Sure… just PM them to me on here. Ooops… That won’t work…… … :person_facepalming: My bad.

You can but it will be tomorrow before I can get them to an image hosting site & get them up.

Either one is fine……

Flashem · 2018-01-09T06:08:09.000Z

teacher:

[PART 1] Official BLF GT Group Buy thread. Group buy officially closed! Lights shipping. - #14863 by bhtune

Post 14913

bhtune:

I made a quick video that I hope demonstrates why evaluating color temperature on the internet is hard. I hope this is useful to everyone! White Balance is hard and you can’t trust your display devices unless you’ve gone through great pains to make sure everything is matched!

BLF Color Temp on Vimeo

Is it just me that can’t hear the audio on this video??
I am on my phone & that may be it. But I can barely hear a bit of mumbling.
It looks like an interesting & informative video too……

Yes… It was absolutely hard to here through my comp speakers. However, after putting on my headphones and thrning up the volume it was perfect. I was a little upset to see the video cut off during each light being turned off. Nevertheless, great video!

yclongthrow · 2018-01-09T06:09:13.000Z

teacher:

yclongthrow:

teacher:

yclongthrow:

I noticed that the reflector on my GT has an orange peel to it, not the super smooth appearance of my other throwers. I hope that this didn’t result in too much lux decrease.

Aside from that this thing is great!

Any chance you could post a close up picture?

I believe you… but would just like to see it. .

I took a few pics which demonstrate it quite well. Can I email them to you or Facebook message them so you can post? I completely forgot how to post pictures. Thanks

Also I completely understand the cost aspect of perfect reflectors, this is after all budget light forum. The GT completely meets expectations.

Sure… just PM them to me on here. Ooops… That won’t work…… … :person_facepalming: My bad.

You can but it will be tomorrow before I can get them to an image hosting site & get them up.

Either one is fine……

I was able to figure out imgur. Thanks

JasonWW · 2018-01-09T06:12:29.000Z

Jerommel:

If this represents the difference between the cool white and the neutral white XHP35 HI Dale has, my conclusion is the neutral white one is a much lower brightness bin or there’s some driver problem.
I wonder if they draw the same current.
Either way, the one is much brighter than the other.

I’m sure the drivers and the emitter current are the same. Why wouldn’t they be? Unless one was ramped up and the other was double clicked. I doubt that, though.

There can’t be very much difference in brightness as they both reach out well beyond the lights specs. 1.90 miles if I’m not mistaken. I would guess that the light we are seeing in Dale’s pictures are well under 0.25 lux. ANSI-FL1 specs measure throw out to 0.25 lux. The GT measured about 1.37 miles according to those specs. So this means by the time it gets to 1.90 miles it is below 0.25 lux.

So there seems to be a small difference in brightness. Very small, but noticable. At least to his cameras sensor.

Also keep in mind that cree bins it’s emitters within about a 7% range. So you can have 2 emitters with the same bin code, like D4, and they will not be an equal brightness. One could be at the upper limit and one at the lower limit so you would measure a noticable difference in output.

Dale, can you remind us what emitter you put in your GT? Was it a D4 like the stock lights or an E2?

teacher · 2018-01-09T06:13:53.000Z

yclongthrow wrote:
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Fixed em’ for you…….

yclongthrow · 2018-01-09T06:15:44.000Z

Thanks

mrheosuper · 2018-01-09T06:19:35.000Z

you are right, it look OP to me, not SMO

yclongthrow · 2018-01-09T06:24:16.000Z

I wonder if it’s just a few of the reflectors that are like mine or all of them.

DoNkEyConN · 2018-01-09T06:24:29.000Z

teacher:

[PART 1] Official BLF GT Group Buy thread. Group buy officially closed! Lights shipping. - #14863 by bhtune

Post 14913

bhtune:

I made a quick video that I hope demonstrates why evaluating color temperature on the internet is hard. I hope this is useful to everyone! White Balance is hard and you can’t trust your display devices unless you’ve gone through great pains to make sure everything is matched!

BLF Color Temp on Vimeo

Is it just me that can’t hear the audio on this video??
I am on my phone & that may be it. But I can barely hear a bit of mumbling.
It looks like an interesting & informative video too……

I had trouble too, ended up using headphones.

JasonWW · 2018-01-09T07:52:55.000Z

yclongthrow:

I apologize for the huge images. What should I resize them to?

As far as the machining lines being the cause I’m not sure if that’s the case. My C8 has machining lines but the reflector is still smooth. Same with my old school throwers like fandyfire with 50ish mm reflector.

The GT reflector has lines in addition to what appears to be uneven deposition.

I’ll wait for someone with more knowledge to chime in. Obviously the unprecedented size of the GT reflectors limits comparison to other reflectors to some degree.

I would say yours is normal. My reflector looks the same. The machined lines are pretty small and then when that deposition layer goes on you get that strange looking pattern. You can see it in VOB’s videos as well.

I’m sure other people who have their lights will say they also have the same pattern. Where are they? Maybe all asleep? Lol