the GearBest SK68 clone.

Got it in today.
It has the ‘normal’ lens you see everywhere. Pity…
Bezel has rather sharp corners. Put it in your pocket ever so tactically, or ouch… :stuck_out_tongue:
And then we have the emitter.
It looks like a XP-G with a smaller dye, or like a XP-E with a bigger dye…
But what’s so weird is that everything under the dome is yellow, even the bond wires.

I’ll post a pic later.
(I have to use a big old lens for macro photos)

Anyway, your thoughts on your $3.— GB SK68 deal?

I’ll be back later today, gotta go now….

Ah yes.

I have a bunch of SK68s and clones.

Most of them have the standard 18mm wide aspheric lens. However I do have one that has a 20mm wide lens. Not sure where I got it.

It’s my 4th sk68 clone…
Can’t get a good picture yet, but the projection is as good as identical to an XP-E.
I’ll try tomorrow, don’t really have a ready to go setup for macro pic…
I’m using a 60 year old Leitz collimator lens… :bigsmile:
But never seen this all yellow .?. everything under the dome.

Now where’s that database page with all the pictures of different LEDs again…

O, by “normal lens” I meant the bigger one, which many many zoomies use.
I prefer the smaller one, which has relatively shorter focal length, so it ‘catches more light’ when focussed
The drawback to some is that the projection of the dye is larger in that case.

My understanding for aspherics is that:

Width of the lens - this governs how intense the spot is and how much throw you get. Wider the lens, the more lux it has and more it throws.
Thickness of the lens - this governs the focal length. Thicker the lens, the shorter the focal length. Shorter focal length will produce a wider spot so you’ll illuminate a wider area, but it won’t actually have any more throw than the same width lens with a long focal length.

So in theory, the best Sipik clone would be one with a 20mm wide lens instead of the 18mm wide lens.

Maybe the LED is an XT-E?

http://www.cree.com/LED-Components-and-Modules/Products/XLamp/Discrete-Directional/XLamp-XTE-White

I would say the beam is tighter with a big lens, because to a big lens, an XP-E is almost like a point source, so you can (if your lens is good enough) make better parallel rays with a wide optic.
But also with short focal length so it captures more light when in focus, because it’s relatively closer to the emitter.

Personally I’m more into OTF (out the front) lumens, if I say it correctly.

That is also true…

It depends on what you want from it.
in practice the smaller lens simply collects more light, so you have more light out the front.
It’s a compromise, of course…

For a true thrower you would need a recoil setup with parabolic mirror that takes ALL of the emitted light.
or maybe a combi of reflector and lens (focus the spill)
Or a TIR ! I think TIR is the future.
But it doesn’t zoom too well…

It’s not a XT-E.
I have one coming from FT.
I will discover why it’s not popular myself. :stuck_out_tongue:

Tomorrow I will have some pics to show what I mean.

I have 2 SK68 with the wider lens. Both are less bright in flood mode than the usual ones and have same die projection size. Probably the difference the size of the lens makes is much less that the variance in other factors

mine has not arrived ….

to make “makro fotos” use a android phone and Coyz Magnifier free :wink:

I've looked at the cree LEDs some more and it looks like it is the "XP-E high efficiency", which has the yellow colour on the PCB too.

I just picked up 5x UF SK68 on eBay for $4.27 +1.99 shipping, not bad for $1.35 a piece shipped !
Not too crazy about the progressive 3 mode switch though.

Holy cow…that’s cheap! Who did you get them from?

Just search on eBay for 5pcs Cree Q5, sometimes people aren’t watching and you can get away with it, normally they get the bid up to $25 for 5pcs.
What surprised me was I thought it would just be some clone of the SK68, but what I received was actually Ultrafire with the circled “R” brand.

I always look for lot sizes when I bid, most people just look for one, why pay for one when I got 5 for less ! …LoL

5pcs Cree Q5

More

Awesome, that’s for letting me know…I appreciate it. :beer:

Got mine today. I am pretty disappointed of the poor build quality of this light even for a $3 light. The lens and star are scratched…and the LED was badly uncentered so I had to shift it over to correct it. The shield thingy which looks like it’s made out of tin is warped and doesn’t look like it can be removed without cutting it out. Also the zoom action is very wobbly. I thought maybe the pill was loose, but that’s not the problem. Are all the SK68 clones built this badly or is the GearBest SK68 among the worst of them?

All these things I could live with if it performed okay…but I find the beam extremely ugly and ringy. I expected that in the throw position, but I was surprised at the ugly uneven ringy-ness in the flood position. I’m not sure what is causing it. Could it be the warped shield? What is its purpose? What would happen if I ripped it off? Is it holding the star down?

I also find the size of the flood kind of small…and on a AA battery it’s really dim. I don’t even think it would be a great gift for non-flashaholics. The cheap Defiant 3xAAA light I got from Home Depot is much brighter and the spill is a lot larger and more useful than the SK68 in flood mode. The tint on my Defiant is also a nice warm white while the SK68 is on the cool blue side. I know it’s not a fair comparison because the HD light uses 3 AAA batteries and it is twice as expensive…but I am saying that even as a gift to someone who isn’t into flashlights, they wouldn’t be terribly impressed…at least not using an AA battery.

The SK98 clone I have is significantly better built. I know I read that some people prefer the SK68 clones over the SK98 clones, but I personally think my SK98 clone is a far better and more useful light. Better build, brighter, nicer less ringy beam, nicer clicky action, and WAY bigger flood beam. And I got the XML SK98 clone on eBay for $7. I know that more than twice as expensive, but it’s more than worth the extra $4. The only think I like about the SK68 clone is the form factor.

Sorry for the bad pictures…my camera had a hard time focusing.

Yes, the rings in flood position are killing me, too. Especially after a much better 1 mode clone I got from eBay. I figured Gearbest one would be the same, just 3 mode. Nope. They are completely different, every part of them. I made some (bad quality) pictures.

First thing I absolutely had to do was to get rid of mode memory, so I took it apart.
The pill:

Notice the damaged o-ring:

Driver exposed:

A clearer picture. Notice pencil modded resistors, memory only works for 2-3 seconds, success!

Now a series of pictures comparing the two clones. 1 mode on the left, Gearbest 3 mode on the right.













The 1 mode clone from eBay with it’s narrower lens (20mm vs 18mm) has a much wider beam in flood position, no ugly rings.
On max zoom die projection dimensions are exactly the same, Gearbest’s being a little better focused and with much more pronounced rings.

Make sure to black sharpie all of aluminum of the pill that the light from the emitter hits. Doing so will greatly reduce the rings and make for a much nicer beam.

Those look like equally bad clones there… :smiley:
They all seem to have stopped drilling holes in the tail rim…
They have no function anyway, but i liked the look…
I see you also have the XP-E with everything yellow under the dome.

Aha, thanks.
(late reaction…)

Yup, that’s exactly like the one I got from GB, off center pill and
press fit reflector/retainer, and everything.
Offcenter for the emitter doesn’t seem to make much difference, really.

I can’t quite make out the pencil modded resistors in your picture; can you say what to look for?

Thanks for those pics xelario! I have never done a pencil mod before. Do I just make a pencil line on the resistors I circled below?