New Sofirn SP33 V3 !!

If I understand you correctly, your directly associating lux with lumens? These are completely different measurements. Are you integrating all the light? You have me quite confused.

A TIR lens or OP reflector. Anything that helps blend the corona into the main hot spot. Diffuser films works, but you loose efficiency.

Thanks. Those voltages are right in line with what I observed too. Maybe also try the same 18650 cell in the SP33v3 for one less variable, but I’m guessing the result will be similar.

Well it already has an OP reflector. Perhaps it needed stronger OP. Blending the corona and reducing the blueness of the spill make it much much nicer.

On a side note, I’m finding I’m not the biggest fan of strong hotspots. Blended, homogeneous, wide beam profiles seem more pleasant and useful to me, certainly for shorter distances. Also, hotspots seem to give a tunnel vision effect, even (especially?) after turning off the flashlight.

Astrolux EC01 has an ever so slightly slightly stronger OP reflector than the SP33 V3.0 (identical reflector and glass, o-rings and SS bezel) just enough that you can see it in the beam pattern (bit smoother - actually the reason I've noticed it in the first place)

For high tint shift emitters like the XHP 50/70, XP-L2, XP-G3, etc. a narrower reflector with the smallest emitter hole as possible helps much more than an OP texture (and gives a cleaner, sharper beam) - the lower the angle between the base of the reflector and the emitter, the less tint shift - the higher the angle, the stronger the tint shifting in the corona.

Thanks for the tip 80T. Any beamshot comparison of the two?

If a drop-in reflector replacement would fix the beam, that would be very nice and convenient.

No, I don't have a beamshot comparison, as I don't have a good way of taking such pictures. The difference is marginal and the tint between the two would be much more noticeable than the beam pattern itself. Being the same geometry reflectors, the tint shifting is also the same, just a little bit smoother beam on the EC01, but actually looking worse because of the overall cooler tint vs my SP33, thus more tint shifting into green.

I only have the version 2, but the reflector on it is just barely OP. It’s almost SMO if you look at it closely and look at how sharp the hot spot is. If they made it more OP it would definitely help the appearance.

Thanks. Those voltages are right in line with what I observed too. Maybe also try the same 18650 cell in the SP33v3 for one less variable, but I’m guessing the result will be similar.


I repeated the SP33v3 USB C charging tests this time using the Sofirn branded 26650 5500mAh battery that shipped with the flashlight plus the Sofirn 18650 3000mAh that shipped inside the SP40.

With nothing attached to the USB C cable the USB 3.0 port in my desktop PC puts out 5.08v monitored on a U2 USB power meter.

When the USB C cable is inserted into the USB C port on the SP33v3 the volts drop to 4.73v and the charging amps is 1.58A.The test began with the battery testing at 3.65v

About half way through the charging the displayed volts starts creeping upward while the displayed amps starts creeping lower.

The charging ends with the volts back at 5.08v and the last displayed amps was 0.278A.The battery tests at 4.15v at the end of charging where the power button displays blue.

The next test is with the Sofirn 3000mAh 18650 in the SP33v3 inside the plastic sleeve.Again as with the Sofirn 26650 5500mAh battery the displayed 5.08v dropped to 4.73v when the USB C cable was inserted in the SP33v3 USB C port and the charging started at 1.578A.The battery tested at 3.65v when charging began.

About half way through the charging the volts stated rising and the amps dropping.

When charging completed with the power button blue light displaying volts were back at 5.08v and the last displayed charging amps was 0.267A.The battery tested at 4.14v

Both batteries were then placed in an Xtar VC4 charger until red charging lights turned to green.

The Sofirn 5500mAh 26650 added 185mAh and tested at 4.20v

The Sofirn 3000mAh 18650 added 118mAh and tested at 4.19v

Hope this helps!

Don’t keep li-ion flashlights in hot boxes, it’s not good for them.

Never gets hot in Texas

If I leave the car in the sun it's only for a short time to flow LEDs onto MCPCBs on the hood

whatsthepoint So the results are consistent. Final voltage around 4.14-4.15V. How soon did you measure voltage after charging ended?

Within a minute after charging completed and the USB C cable was removed from the light.

Oh, I see. Would be good to measure it again after an hour or so to see the resting voltage.

How are you measuring voltage? I hope you’re not removing the cell and checking it because the voltage will read higher since it’s not on load

Yes, this is the only way to measure it. I’m not sure the voltage sag matters as I’ve tried 18650 and 26650 and the resting voltage seems to determine whether Turbo works or not.

I am removing the battery and measuring the voltage. I realize the load voltage will be somewhat less but these are new cells fresh off the charger so it seems too soon to lose turbo. I have been meaning to see what voltage I lose high. That’s more important to me. It is annoying having to double press to get to high after dropping turbo.

After about 1.5 hrs rest the Sofirn 26650 5500mAh measured 4.14v,almost the same as measured soon after the USB charging finished and the blue power button led on.Placed in the Xtar VC4 charger it gained 190mAH capacity at 4.20v

The Sofirn 3000mAh 18650 dropped a point to 4.13v after about 1 hr rest.

****While USB charging if I loosened the tail cap ever so slightly the USB charging stopped.

****Also the light can easily be turned on accidentally.I find the side switch is quite sensitive.

Run Times and Measured Surface Heat.

Items used:

Sofirn SP33v3 original and unmodded using Group 1

Sofirn branded 5500mAh 26650,fully charged to 4.20v

Thin Wire digital temperature sensor

Android Cell Phone timer

I attached the thin wire temperature sensor to the head of the SP33v3 on a flat area on the left of the power button using a small swatch of duct tape.The sensor is powered off a SATA power connector in my desktop PC so it's about 0.25meters away from the PC.

The room is 22.2C but near the PC it's 24.7C

With the senor displaying temperature at 24.7C I double clicked the power button turning the flashlight on in Turbo mode.At the same time I started the timer on the cell phone.

Turbo Mode ran for 1 minute 7 seconds and reached a displayed temperature of 56.0C at which point the SP33v3 stepped down to High Mode.It ran in High Mode for 2 hours and 50 minutes before going into Medium Mode and the power button started flashing red.

At this point I shut the light off and removed the 26650.

The 26650,within 30 seconds of removal,measured at 2.80v.

After quickly putting the 26650 back in the SP33v3 I restarted it on Medium.

In Medium Mode the surface head temperature displays at 27.4C

I'm now waiting to measure the volts when the light goes off.

Light shut off at 2.61v

What is the lumen on high mode? Was it regulated output?

These are my tests done with the tools at hand.If they are of any value to anyone reading them then the post has served it's purpose.

If you wish to supply me with the tools and instructions to get the things you mention I'll be more than happy to accept.