Contents

• Pricing & Availability
• What comes in the box?
• Design & Construction
• Size & Measurements
• User Interface
• Emitter & Beam
• Mode Chart
• Runtime
• Driver & Regulation
• Switch
• Carry & Ergonomics
• Batteries & Charging
• Competition
• Conclusion

Pricing & Availability

Sofirn sent me this light in exchange for an honest review. Here is the official product page where you can see current pricing. If it’s popular enough, Sofirn will also begin to stock it on their Amazon store.

What comes in the box?

The box is one of Sofirn’s printed retail boxes rather than their plain cardboard boxes. There’s a plastic vacuum-formed insert inside to hold everything in place. It’s nothing fancy but it does the trick. The following items are included in the box:

• The light itself
• Battery (inside the light)
• Pocket clip
• User manual
• USB A-to-C charging cable
• Spare O-Rings
• Lanyard

Design & Construction

Build quality is great, even a little better than usual from Sofirn. It feels dense and sturdy. The anodizing is a bit matte and it feels thick and evenly applied. The threads are smooth, trapezoid cut, lubricated, and anodized. Interestingly, the tailcap and bezel thread inside the body instead of outside.

Size & Measurements

Mini Maglite | Olight Warrior 3S | Sofirn IF23 | Convoy S12 | Emisar D4K

Measurement	Measured (mm)
Bezel Diameter	27.5
Maximum Head Diameter	32.9
Length	120.5
Switch Diameter	10.9
Switch Proudness	1.4
Lens Diameter	U/M
Lens Thickness	U/M
Reflector Hole Diameter	U/M
Reflector Diameter	U/M
Reflector Height	U/M
MCPCB Size	U/M
Battery Tube Diameter (internal)	22.3
Body Diameter (mode)	27.5
Ride Height (sticking out of pocket)	7.8
Pocket Clip Space (for pants material)	3.1
Pocket Clip Space (at mouth)	2
Pocket Clip Width	7.1
Pocket Clip Thickness	1.0
Pocket Clip Slot Width	5.3
Pocket Clip Slot Diameter	25.0
Tailcap Diameter	27.6
USB Port Depth	2.8
USB Port Height	6.4
Included Battery Length	70.7
Included Battery Diameter	21.5

Weight without battery: 120g
Weight with included battery: 189g

User Interface

This UI is overly complicated and frustrating to use, primarily because there are too many functions to control with just one switch.

The actions are # of presses followed by a hold (H) or a release (C). So, “1C” is one click and release. “2H” is two clicks but you hold down the last one. I’ll refer to the three channels as “Front”, “Side” or “RGB”.

State	Action	Result State
Off	Do nothing for 3 minutes	Lockout
Lockout	1C	Two low blinks (front) to indicate lockout
Lockout	2(or more)C	Unlock to On (previously used white channel)
Off	1C	On (front, memorized mode)
Off	1H	Moonlight (not memorized)
Off	2C	On (side, low)
Off	3C	RGB (color & mode memory)
On (front and/or side)	1H	Cycle mode (front and/or side, low-med-high or smooth ramping)
On (any)	1C	Off
On (front and/or side)	2C	Turbo (front and/or side)
On (front and/or side)	4C	Toggle stepped or smooth ramping
Turbo (front and/or side)	2C	Strobe (front and/or side, dual frequencies)
Strobe	2C	SOS (front and/or side)
SOS	2C	Beacon (front and/or side)
Beacon	2C	Strobe (front and/or side, dual frequencies)
RGB	1C	Off
RGB	1H	Smoothly change color (RGB)
RGB	2C	Toggle mode (RGB, constant or ~1hz blink)
RGB Blinking	3C	On (front and side)

What they got right:

• Clicking turns the light on/off and holding the button changes modes. That’s the way almost all e-switch flashlights should work.
• Some common shortcuts work correctly. 1H from off for moonlight and 2C from on for Turbo are common shortcuts that work well.
• Shortcuts to the 3 channels are useful. 1C from off turns on the front. 2C from off turns on the side. 3C from off turns on the RGB. It’s not as good as having a dedicated switch for each, but it is nice to be able to jump straight to the one you want. Unfortunately that doesn’t work if the light is in lockout first.
• You can choose between stepped or smooth ramping. Many enthusiasts prefer smooth ramping these days, but some still prefer stepped ramping. It’s nice that Sofirn is accommodating both here.

What they got wrong:

• The automatic lockout here is really bad and it can’t be disabled. Sofirn should have spent their time making a better switch that doesn’t turn on by accident. Instead, they added this “feature” that makes the light more complicated and inconsistent to turn on even when you want to.
• Unlocking turns on the light to the previously used channel and that adds to this light’s inconsistency. There’s no way to tell if the light will turn on the front LED, side LED, or both. If it’s the wrong one, then you have to turn off the light and then turn it back on. This problem could be alleviated by eliminating the automatic lockout, not automatically turning on when its unlocked, or by using separate switches to control the different channels.
• There’s no way to get to moonlight from lockout. If you’re in a dark place and need a little light, but don’t want to disturb others or blow out your dark-adjusted vision, you’re out of luck. You have to unlock the light first, which turns it on to the previously used bright mode, then turn it off, then enter moonlight.
• There’s only one switch and that’s not enough to control three different channels with several modes each. It makes the whole UI too complicated and inconsistent. I’ll discuss this more in the switch section.
• Not enough color modes. The only color modes are constant on or blinking. It would be cool to have some additional modes like constant-smooth-color-changing, random-color-disco, orange-white road-hazzard flasher, and/or red-blue police flasher. The RGB just feels under-utilized. I do not want them to add these to the existing UI, but only after they fixed all the other bigger issues I’ve mentioned.
• 1C does not always turn the light off. 1C should always turn the light off, regardless of the mode. In this light, 1C from Turbo returns you to the previous mode (which should be done via 2C from Turbo). This is a common problem on Sofirn lights and I often found that I had accidentally left the light on when I tried to turn it off whole in Turbo mode.

Other thoughts:

• Neither Turbo nor Moonlight are memorized. Normally I really like that, because normally a light will have dedicated shortcuts (from off) to both of those modes. Unfortunately, this light does not have any shortcuts from lockout to Moonlight or from lockout to Turbo. Memorizing them would be better, but I’d still prefer Sofirn fix the core issue: the automatic lockout and single switch.

Emitter & Beam

IF25 has a cool-white 3-volt Cree XHP50.2 LED nestled in a forward-facing orange peel reflector. It’s bright and efficient but doesn’t have great color properties. There’s also 20 CSP1313 LED’s on the side with nice white color properties. Plus there are 10 RGB LED’s as well. Overall I think it’s a fairly comprehensive emitter setup. I would not mind if they swapped the XHP50.2 for an SFT40 to get more throw, though.

The front beam has wide, cool spill with a medium-sized greenish hotspot. It’s not pretty but it will get the job done. The side beam is just widely diffused light, not really a beam, so I didn’t take any beamshots of it.

In the beamshots below, the tree line at the back is 100 meters away. The short, flat hill is about 35 meters away.

Mode Chart

Disclaimer: All of my measurements are taken at turn-on. Lumen measurements were taken on a Texas Ace 3.5″ Lumen Tube. A candela measurement was taken at 10 meters with an Opple Light Master III on the highest brightness, and other candela figures were calculated relative to that. CRI, CCT, & DUV data was taken for each mode from a few feet away at the center of the hotspot with the Opple Light Master and Waveform DUV Calculator. Runtime tests were performed with the Ceilingbounce app on my smartphone. All of these tests were performed with a fully charged included battery unless otherwise specified. I cannot measure moonlight directly, so moonlight readings are calculated based on the brightness relative to the next-lowest mode. None of this is professional equipment, so take all of these measurements with a grain of salt.

Above are the official specs, followed by my own measurements below.

Level	Lumens	Candela	Throw (Meters)	CRI (Ra)	Color Temp. (K)	DUV (Tint)
Turbo	2400	13300	231	64	5360	0.0107
High	860	4766	138	64	5370	0.0109
Medium	350	1940	88	63	5380	0.0111
Low	88	488	44	64	5350	0.0106
Moonlight	0.5	3	3	62	5100	0.0138

Level	Lumens	Candela	Throw (Meters)	CRI (Ra)	Color Temp. (K)	DUV (Tint)
Turbo	490	240	31	97	4720	0.0050
High	160	78	18	97	4680	0.0051
Medium	64	31	11	96	4700	0.0061
Low	7	3	4	98	4630	0.0051
Moonlight	2.5	1	2	99	4640	0.0045

Moonlight: I find that ~0.5lm is just right for moonlight. 0.1lm and below is too dim to be useful and above 1.0lm is too bright for some situations. The moonlight on this light is just right, but you can’t access it directly from the near-constant lockout.

Mode Spacing / Ramp Speed: is good. There are no weirdly small or large jumps in the stepped ramping and the smooth ramping is pretty smooth, much smoother than previous Sofirn models I’ve tested. This is a nice improvement over previous Sofirn models.

Runtime

Performance: is fine. Usable brightness and plenty of runtime. Turbo lasts nearly two minutes before “thermal regulation” begins.

Thermal regulation: is… well… look at all the zigzagging in the graphs. It works but it constantly overshoots so the brightness just goes up and down and up and down and up and down. It’s slow enough that you don’t notice when using the light, but this has been a minor issue in Sofirn flashlights for a long time and I wish they had fixed their thermal regulation algorithm by now.

LVP (Low Voltage Protection): the switch will blink red when the battery is critically low, then eventually the light will shut off completely to prevent the battery from being over-discharged.

Driver & Regulation

Based on Sofirn’s history and the regulation performance below, I believe this light is using a cheap FET-only driver.

Regulation is poor. Every mode is affected by battery voltage. That’s not unusual for Sofirn, as they tend to use basic FET-only drivers in many of their models.

Note: All regulation measurements are taken at turn-on so they do not reflect any thermal or low voltage stepdowns that may occur. A value of 0 indicates low voltage shutoff immediately upon activation.

PWM: No PWM is visible to my eyes or nor audible to my ears. My phone camera was able to detect some form of flickering on Low, Medium, and High modes from both the front and side emitters. It may not be suitable for photo/video work.

Parasitic Drain: ~80 microamps. That will take seven years to drain the included battery.

Switch

IF23 is controlled by one electronic side switch. It’s got a hard plastic boot that sticks out and has a clear spot in the center with backlighting underneath. The backlight glows when charging and when you turn the light on to indicate charge status. It has several problems:

• The switch is kind of mushy and not super tactile nor clicky. There’s a lot of pre-travel before the click and it’s got a lot of tilt-play in it. Overall it’s usable but not great. The fact that there’s only one switch is also an issue because it’s difficult to control three separate light channels with a single switch.
• It sticks up past the body and can be pressed by accident fairly easily. I suspect that’s one of the reasons Sofirn decided to add the annoying auto-lockout feature. I wish they had put in a higher quality, recessed switch instead of putting a band-aid over the problem with auto-lockout.
• One switch is not enough. There are far too many functions packed into this light to be controlled by a single switch. It needs a second one (ideally a 3-position rotary, slider, or rocker switch) for channel selection. The main button should only control on/off and mode changes. That would be dramatically more usable and consistent.

Carry & Ergonomics

IF23 has great ergonomics. It fits great in my hand and my thumb lands nicely on the button with the clip indexing between my knuckles. The arrow-shaped milling on the sides provides a bit of extra grip. A forward grip is most practical but a pencil grip can work too.

It’s a larger light for daily carry but it carries well for its size. It slides in and out of the pocket nicely and it carries deep. There’s no flared bezel or any other protrusions so it’s very comfortable. I like that the clip is indexed and will always stay directly opposite the button instead of being able to rotate around the body like on many other lights. It’s a bidirectional clip so you could theoretically clip it to a hat, but this light is far too heavy for that. The included clip is black, but I had an identical silver one that I installed because I think it looks better.

Despite the great ergonomics and good carry-ability, I did not carry this light and cannot recommend it for regular carry. The user interface is too inconsistent and frustrating to use.

Tailstanding is very stable and works well, especially on a metal surface. It’s perfect for standing on its tail with the side emitters lighting up the area.

The magnet is just strong enough to hold the light up on a vertical surface, but not super strong. I would not trust it to hold in place in a moving vehicle or on a rickety cabinet, but when stuck to a solid, heavy object it should stay put.

Batteries & Charging

IF23 includes a 5000mah unprotected flat top 21700 cell. It will also accept protected 18650 cells. It will not accept unprotected flat top 18650’s nor protected 21700’s. The positive contact is a brass button and the negative contact is a beefy spring.

Charging is facilitated by a USB-C port on the side of the light. It’s covered by a rubber flap that’s pretty average. Both A-to-C and C-to-C cables worked for charging. It can also work as a powerbank with a C-to-C cable. You can use the light when plugged in (with or without a battery), but only in front-low, side-low, or RGB modes.

Competition

Here are some lights in the same class and how they compare.

Sofirn SP35: same brand, battery, clip, charging, and overall size. A little less brightness, more throw, no magnet, and no side LED’s. Much better driver with better sustained output and better regulation.

Lumintop E21C: extremely similar to IF23 but more expensive, probably better performance, different (not necessarily better) UI, and no RGB

RGBW Photo Light Panel (example): smartphone-shaped, USB-C charging, adjustable color temperature, tripod mount, no far-reaching throw LED, non-removable battery

This section is not comprehensive. If I didn’t include a particular light here, it doesn’t mean it’s bad or doesn’t deserve to be here. I simply cannot list every possible competitor.

Conclusion

This light is a very cool concept that’s severely let down by a bad UI and switch design. The performance didn’t live up to the advertised specifications and the regulation is poor. If you don’t really care about ease-of-use and you just want a flashlight with a bunch of bells and whistles, this is an affordable choice. Otherwise, I’d stick with a regular forward-facing flashlight and get a separate RGBW LED light panel for your side illumination needs. I do hope that Sofirn makes an updated version in the future with the UI and switch improvements I suggested and some better regulation.

Thanks to Sofirn for sending me this light for review!