The Sceptre - PScal's quest for a superthrower

Very nice! I like that you can actually see the shape of the LEDs package in the beam. 1.77Mcd is great!

You could probably still optimize it a bit though. With 75mm lens diameter with no ar-coating and this LED it should be possible to get up to 2.8Mcd with a 315cd/mm^2 LED and perfect placement of the collar. The collar can increase the luminance of an XP-G2 LED by up to 120%. This effect might actually be greater with an even smaller LED.

I would think about modifiying the light so you can use the more high-quality lens. It should make a difference with such a tiny LED because of its more accurate shape.

I wish those wavien collars were more readily available. Pretty sweet build you got there

The initial lux readings are probably inaccurate. I will work on getting better long distance readings.

Due to the easy access I designed into the light, it is definitely possible to spend time optimizing focus of the collar. I will spend more time on that and rig a lux meter to give me real time info while focusing.

The optolife lens was a disappointment. I will take photos to show the difference. That should explain everything. At this point I plan to stick with the dx lens. Lenses get so expensive so fast. Also, part of what I enjoy about this light is the beauty of the elephant host. I don’t want to change the looks to fit a different lens.

Also, keep in mind that I am not driving the LED at 2.5 amps. With 6x 7135 chips, the LED sees 2.28 2.1 amps. I may upgrade the driver at a later time, but I am very close to the top of the curve and diminishing returns are in effect.

Thanks to everyone for the encouraging words and tips on furthering the performance of this light.

I spent some time with the lux meter and the wavien collar. I observed something unexpected due to the asymmetrical shape of the LED. I get the highest lux reading when the rectangle is perfectly centered over the rectangle. However, the die is not in perfect orientation over itself. My thoughts are that I should focus on the die itself and not the entire package / highest lux reading. I’d like to hear others’ thoughts, too. As an experiment, I can glue the collar in place both ways and take measurements, but my free time is a bit limited and I think some discussion could be interesting.

I also realized that my batteries were almost dead, so I charged them up. That should help a bit with lux. :person_facepalming: I’m going to officially scratch the initial lux readings until things are worked out.

Here are photos to illustrate the difference between the Optolife and the DX lens. The optolife lens scatters light. These photos are taken with the same camera settings, stepped down so as not to overexpose. In person, the scattering is much more pronounced.

DX:

Optolife:

Wow that is bad.
My optolife lenses had almost none.
What is the product code of the one you bought?
Are you sure it was plano-aspherical?

A298
http://www.lens-manufacturer.com/singlet_lens/A298.html

Ok well that’s unfortunate.
Must be a defective one, or it’s bad because of how low the F number is.
My A380 an A037 are higher F.

I would recommend this one for people who are looking for a precision 75mm lens, it’s pretty cheap:

Excellent build.

The Sceptre is not performing as I hoped it would. Even with fresh batteries, the lux meter gives me lower readings than my GT and from the previous iteration of the light. I suspect the LED may have been damaged or not like being overdriven. I am considering swapping back the “king” xp-g2 or installing a flat black LED. The quest for throw continues!

My guess it that the lens isn’t precise enough. You can check this by looking at the light from far away. The entire lens should be yellow (or lit up when turned on).

I may have to get my wallet out again. I should amend my last post to say: The quest to “throw” money at the problem continues! :money_mouth_face:

That Edmund lens has an even shorter focal length than the Optolife.

You should calculate if this lens actually makes sense with the emission angle of the Wavien collar. If the focal length is too short th lens wont be used completely which leads to less throw.

I think this is the lens used in the Mjölnir from Vinz.

Absolutely. The dx lens is right at the sweet spot for focal length and the collar.

You’re right, the F number is too low for us with a collar.
The DX lens looks good enough.

I did a quick experiment without the collar

BLF GT 1610 lux at 80ft
The Sceptre with Synios (no collar) 1170 lux at 80 ft
The Sceptre with XP-G2 S4 2B (old style) (no collar) 1200 lux at 80 ft

So, right now the xp-g2 is winning over the synios. I’ll build up a module with a Flat Black and give it a shot, too.

Hey @the_driver, could it be possible that the high cd/mm^2 from synios LEDs is because of the white “cup” area around the LED?

Then when we divide the luxmeter reading by the die area we get a higher number despite the die having lower intensity and the reflected light from the sides helping increase the number?
:frowning:
You can see from the beamshots that there is clearly a lot of light coming from the area around the LED:

This doesn’t happen with the black flat because the surface is 100% flat around the LED.

Maybe message koef3 and ask him to redo his intensity measurements after blacking out the area around the die!
That would be really unfortunate if this is the case, and our 300cd/mm^2 LEDs are false readings.

I just had the same thought, Enderman. This method of measuring the cd and dividing by the die area does not work for many LEDs for this reason.

This is really unfortunate.
If pscal is getting lower than the old XP-G2 then the black flat is still highest intensity, and CFT90 is second!
That basically means I wasted like $100+ on LEDs and drivers :frowning:
Hopefully koef3 can retest then and we can find out the true numbers.

At least now we know that for any future tests of LEDs, the area around them definitely needs to be blacked out, especially if they are not flat.
I think it may still be possible that the flat white area around the black flat could be artifically increasing the lux a little, but not anywhere near the amount for the synios.

Yes that is possibe, as I have now learned together with Köf3. It is indeed very unfortunate and I have not found a way to predict this effect berforehand.

The standard way of measurering the luminance has worked for years. :frowning: