Sofirn IF24

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Sofirn IF24 review

Sofirn IF24 specifications

Brand & ModelSofirn IF24
Flashlight categoryEDC flashlight, worklight
LEDLuminus SST40 + COB
Max. output2000 lumens
Max. beam distance251 meters
Max. beam intensity15,800 cd
Battery config.18650
Onboard chargingUSB-C
Main modes5
BlinkiesStrobe, SOS, Beacon
WaterproofIP66
Review publication dateMay 2024

Review intro:

If you’ve spent any time in the budget-minded side of the flashlight enthusiast world, you’ve certainly run across the Sofirn brand. They’ve been around since 2016-2017, and seemingly had some roots in what was ThorFire back in the day. I don’t know what the exact relationship was, but I know a few ThorFire models seemed to fade into Sofirn models (eg, the Q8). And nowadays Sofirn seems to also have some sort of corporate relationship to Wurkkos (sister company? shared ODM?). Whatever those relationships are, it’s fair to say that Sofirn has been heavily involved in the budget flashlight space.

Sofirn has a really pretty wide portfolio. Some lights are very basic and to the point. Today’s review light, the IF24, is not one of those flashlights. This feature-packed flashlight has a front-facing primary emitter (CW SST40) plus side-firing white + RGB LEDs. Control is handled by a rotary + e-switch combo, much like an Olight Arkfeld. While this setup may not be an original idea, I do like it quite a bit instead of having overly complicated button-press sequences for switching emitter channels.

Like many flashlights, to get started with the Sofirn IF24, you must first unscrew the tailcap and remove the isolation disc.

What’s in the package

Compared to some packaging that I’ve seen from Sofirn, the container for the IF24 is particularly nice. Not that the others were bad, per se, but this one is particularly good – if you care about packaging. Let’s just say that the switch design isn’t the only thing that’s reminiscent of an Olight. The carton consists of an outer sleeve with a picture of the flashlight. Removing that leaves you with a magnetic-closure white box, in which the contents are separated by white foam and a little white box for accessories. There’s even an orange “thank you” / quick start card, just as you would find when opening up the nicer Olight packages. Very nice. The total of the contents are:

  • Sofirn IF24
  • Battery
  • Charging cable
  • Lanyard
  • Spare o-rings
  • Manual

Flashlight in use, Build Quality, and Warranty

The Sofirn IF24 is a sort of an elongated U-shape design instead of your typical cylinder shape. The flat side of the U is to accommodate the sidelight COB LEDs. This shape seems to add more aluminum, which can be both good and bad. On the plus side, there’s more mass for heatsinking. On the down side, that makes it a bit chunkier for pocket carry. It’s a bit bigger than what I would EDC, but not so large that I wouldn’t slip it into a pants pocket on occasion if I knew I was going to be using it.

As I mentioned in the intro, the IF24 uses a dual-switch setup: a rotary switch for output channel selection, and then an e-switch in the middle of that ring for brightness & mode selection. The Sofirn IF24 is an upgraded version of the IF23, and the main functional thing that sets it apart is the addition of the rotary switch and the accompanying UI changes, making it easier to operate. If you’ve ever used an Olight Arkfeld, it’s a pretty similar experience to that. Though I will say that the Arkfeld maintains an advantage in that you can tell which output channel you’re using as its rotary switch only has 2 positions (or 3 for the Arkfeld Pro): it points to around 11 o’clock and 1 o’clock… easy enough to remember and distinguish by feel. The IF24’s rotary switch has 4 positions and are equally spaced around the circle (and it can be continuously rotated), making it impossible to tell which output you’re using without looking at the flashlight.

The clip on the IF24 is friction-fit, but pretty sturdy. It’s definitely not deep carry. The clip serves its purpose, though. The tailcap of the flashlight is actually the male mating surface of the threaded joint, screwing into the body of the flashlight. That’s a bit different, but makes sense given that the body of the IF24 isn’t cylindrical. The tailcap appears to be flat and looks like it should be great for tailstanding… but it’s not. On my flashlight, the tailcap’s surface is ever so slightly rounded, which makes it wobble around when set down on its end. The tailcap is magnetic, which is very handy for a light that can be used as a work light. But this experience is diminished because of the wobbliness.

The other physical aspects of the Sofirn IF24 are nice. The machining (aside from the tailcap’s convex nature) is great – no sharp edges. The threads are smooth. The anodizing is even and attractive, a bit on the matte side of the spectrum.

Sofirn’s Warranty Policy:

  • Within 30 days of purchase: Contact the original seller for repair or replacement.
  • Flashlights: Within 1 year of purchase: Contact Sofirn for repair or replacement
  • Batteries: Within half a year of purchase: Contact Sofirn for repair or replacement

LED, Lens, Bezel, Beam, and Reflector

The primary emitter is situated on the end of the IF24, a pretty similar layout to most flashlights. The bezel is stainless, but doesn’t provide any drop protection because it is inset within the aluminum. It appears that the bezel holds a TIR lens in place (no glass lens) that sits overtop of a smooth reflector. There’s a cool white Luminus SST40 LED nicely centered in that reflector.

Along the side of the Sofirn IF24 is a large window that houses both white and RGB LEDs. The 22 white LEDs are said to be 5000K in the CSP1313 format, produced by Jin Neng. There are 15 RGB LEDs; Sofirn tells us that those are model FY-1615RGY. The white sidelight is pretty handy, providing a nice flood of light. The RGB LEDs are neat and provide some very fun effects, though I’m not sure I’d get much use out of them, personally speaking.

Spectral measurements: 

I used the Opple Light Master to measure the flashlight at 5 meters distance (1 meter for the sidelight). 

Mode:CCT:CRI Ra:duv
Main LED, Turbo5980 K67.5+0.0061
White sidelight, Turbo5033 K97.3+0.0020

Dimensions and its competition

Dimensions: 

Sofirn IF24MillimetersInches
Length126 mm5.0 in
Width27 mm1.1 in
Height24 mm0.9 in

Dimensions are rounded to the nearest millimeter and the nearest tenth of an Inch.

Weight

Sofirn IF24Weight in gramsWeight in oz
Without battery:98 g3.5 oz
With battery146 g5.2 oz

Weight is rounded to the nearest gram and tenth of an Oz.

Flashlight size comparison with its competition:

Group 1: Olight Arkfeld UV, Sofirn IF24

Group 2: Olight Baton 3 Pro Max, Wurkkos FC13, Convoy S2+, Sofirn IF24, Acebeam E75

Sofirn IF24: User Interface and Driver

The addition of the rotary switch goes a long way for simplifying the operation of multi-channel flashlights such as the Sofirn IF24. The rotary switch is responsible for selecting the output mode (lockout, main light, color mode, and white sidelight).

Available modes: 

  • White modes: Moonlight, Low, Medium, High, Turbo
  • Color mode: stepless color change

Available blinky modes:

  • White modes: Strobe, SOS, beacon
  • Color mode: Police flash, rainbow, RGB waterfall, droplets, neon fade

The operation of the primary white LED and the white sidelight is the same. So in the UI description below, those are described generically as White Mode.

From OFF:

  • White Mode, Press and hold: Moonlight
  • White Mode, Single click: On, last used regular mode (Low, Med, or High)
  • White Mode, Double click: Turbo
  • Color Mode, Single click: On, last used solid color mode
  • Color Mode, Double click: blinky color modes

From ON:

  • White Mode, Press and hold: step up brightness (Low > Med > High)
  • White Mode, Single click: Off
  • White Mode, Double click: Turbo (or from Turbo/Blinky, rotate Turbo > Strobe > SOS > Beacon)
  • Color Mode, Press and hold: change colors (from solid color mode)
  • Color Mode, Single click: turn off
  • Color Mode, Double click: change color blinky mode

Mode memory:

  •  Yes, “normal” (Low, Med, High) and solid color modes are memorized

Shortcuts:

  • To Low: press and hold from Off
  • To Turbo: double click (from Off or On)
  • To Strobe: double click from Turbo

Low voltage warning/protection:

  • There is an indicator LED on the side of the IF24 that lights up for 5 seconds after turning the flashlight on
    • Green constant: 50-100%
    • Red constant: 10-50%
    • Red flashes: 0-10%
  • When the flashlight is on and the battery is lower than 10%, the indicator will continue to flash
  • The flashlight will automatically turn off when the battery is lower than 2.8V

Strobe/blinkies

  • White Mode: double click from Turbo
  • Color Mode: double click

Lock-out mode: 

  • Rotate the switch to the lockout setting 

PWM

  • Yes, there is 19.9 kHz PWM in both White modes

Additional/summary info on the UI: 

  • My one gripe about the operation is that if you desire to know what mode you’re in before turning the light on, you need to look at the rotary switch and its markings

Sofirn IF24 Charging and batteries

The Sofirn IF24 arrives with a Sofirn-branded 18650 battery. It is a non-protected button-top cell with 3000 mAh capacity. The battery compartment has springs at both ends, so it is pretty flexible with which 18650 batteries that you can use.

There is USB-C charging built into the side of the flashlight, covered by a little rubber flap. This charges the IF24 at a pretty reasonable rate, taking 2h 30min to complete a charge cycle. Unlike the IF23, the IF24 does not have power bank functionality.

Charge typeFitsNo fitAvg. charge time
Flashlight with onboard USB-CShort to mid-length non-protected cells. Button-top is ok.Long, protected cells are likely too long to fit properly2h 30min

Performance test

Lumen measurements

How Lumens are Measured: Understanding ANSI FL1 Standards How Lumens are Measured: Understanding ANSI FL1 Standards: The ANSI FL1 standards specify that output in lumens should be measured 30 seconds after turning on, as this is the standardized time for measuring brightness according to the industry standard. This is why we focus on this part in our measurements. The ANSI FL1 standards require an ambient temperature of 22 ± 3°C. We record the ambient the ambient temperature to identify potential reasons for any observed discrepancies.

Lux was measured by a UNI-T UT383 BT at 5 meters. Lumens were measured in a homemade lumen tube using a VEML7700 sensor, calibrated with a calibration light provided by 1Lumen. The included 18650 battery was used in the tests.

ModeAmps at startSpecifiedTurn on30 sec.10 min.
Main, Moon8 mA1 lm11
Main, Low32 mA10 lm1010
Main, Med342 mA150 lm128127114
Main, High1.6 A700 lm553553492
Main, Turbo3.7 A2000 lm13551188 lm552
Main, Turbo at 3.6V1024931
Side, Moon9 mA1 lm0.50.5
Side,, Low88 mA20 lm1515
Side, Med401 mA100 lm3030
Side, High830 mA200 lm6362
Side, Turbo2.1 A550 lm448425 lm262
Side, Turbo at 3.6V302293

Ambient temperature during testing:

  • 24 °C 

Parasitic drain:

  • 61 µA 

The lumen test results came in way under spec. I thought maybe I did something wrong, so I retested and checked my sources… nope. As it comes from Sofirn, the IF24 performs about 40% under their claims.

Sofirn IF24 Battery Life: Runtime graphs

How Runtimes are Measured: Understanding ANSI FL1 Standards About ANSI FL1 runtime standards: The runtime is measured until the light drops to 10% of its initial output (30 seconds after turning on). This does not mean that the flashlight is not usable anymore. The last column shows how long the light actually works till it shuts off. If there is a + symbol, it means that the test was stopped at that particular point, but the light was actually still running. This happens on certain occasions, with certain drivers, firmware, or batteries.
ModeSpecifiedRuntime (ANSI FL1)Time till shut off
Main, Moon20d
Main, Low4d 19h
Main, Med13h 30min14h 26min14h 34min
Main, High2h 15min2h 55min2h 55min
Main, Turbo1h 30min2h 21min2h 35min
Side, Moon20d
Side, Low58h
Side, Med12h
Side, High5h 30min
Side, Turbo3h 30min3h 32min3h 37min

While the lumen claims were well under spec, thankfully the runtimes were pretty close. The flashlight actually ran a bit longer than the specs claim, which is a silver lining.

I compared the Sofirn IF24 runtimes to the Maratac/Acebeam Defender P16 and Fenix LD30R, all of which use a 18650 battery and have a SST40 or SFT40 LED. The IF24’s output is considerably lower than both of the other lights, and its output is much less consistent. It goes to show what nicer drivers can do for a flashlight.

Peak beam intensity and beam distance measurements

About Peak beam intensity: Understanding ANSI FL1 Standards About peak beam intensity The calculated value of distance in meters at which the flashlight produces a light intensity of 0.25 lux. (0.25 lux is about the brightness of a full moon shining on an object). This means that the intensity has decreased so much, it becomes difficult to see darker objects, or objects that don’t reflect light. The columns ‘Meters’ and ‘Yards’ use rounded numbers.

Intensity was measured at 5 meters after being turned on for 30 seconds. A UNI-T UT383 BT lux meter was used. 

ModeSpecifiedCandela measured MetersYards
Main, Moon6 cd
Main, Low89 cd22530 m33 yd
Main, Medium1,242 cd1,27571 m78 yd
Main, High6,650 cd5,500148 m162 yd
Main, Turbo15,800 cd12,100 cd220 m241 yd
Side, Low6 cd
Side, Medium28 cd
Side, High65 cd
Side, Turbo138 cd400 cd40 m44 yd

Ambient temperature during testing:

  • 24 °C 

After seeing the lumen results, the poor intensity observations don’t entirely shock me. I have a sneaking suspicion that a low-drain battery is to blame, as an SST40 (presumably FET-driven) should be capable of more than what we’re seeing here.

Beamshots

Camera settings and distance: Beam shots of the building are taken at 30 m (33 yd) using a Canon EOS R100 with a lens set to 18mm. Manual settings: ISO 800, 1/4sec, F4.5, 5000K.

Beamshots of the following flashlights compared:

  • Sofirn IF24
  • Nitecore EDC33 – Search
  • Powertac Warrior LT G5

Please note that the following beamshots are mainly intended to showcase the beam pattern and beam quality, rather than overall performance. These images are typically taken directly after activation, and in different seasons or weather conditions, and therefore do not fully represent its overall performance. For accurate performance metrics, such as output, beam distance, and runtimes, you need to look at the performance section of this review.

Disclaimer: This flashlight was sent to us for review at no cost by Sofirn. We have not been paid to review, nor have we been holding back on problems or defects.

Final Verdict

Pros

  1. Lots of mode options
  2. Rotary switch makes UI easier
  3. USB-C charging
  4. Handy sidelight
  5. Magnetic tailcap

Cons

  1. Badly missed lumen specs
  2. Missed intensity specs
  3. Tailcap isn’t flat

Explanation on star ratings:

1: Avoid: a match would be a better choice – 2: Poor: significant defect or issues; almost unusable – 3: Average: some defects or issues; but still usable 4: Good: recommended (minor issues) – 5: Great: highly recommended

Reviewer Gabriel
Gabriel

3.5 stars: ★★★⋆

While our star rating provides a reliable indicator, we encourage you to read the full review to make an informed decision based on your own needs and preferences.

The Sofirn IF24 has a lot of tricks up its sleeves. Of course there’s the normal front-facing SST40 output. The rotary switch, though, lets you also conveniently switch between that primary LED and white or RGB sidelights. The neutral, high-CRI sidelight is quite nice and pretty handy. But my enthusiasm for using the sidelights is tempered by the fact that the tailcap doesn’t sit flat, so the IF24 rocks badly when you try to tailstand with it. I was also very disappointed in the lumen and intensity output measurements. They’re not necessarily bad, but they are nowhere near what Sofirn claims they should be. Some of that may be due to a low-drain battery, and some may in part be due to the TIR which tends to have inherent losses. If you’re ok with the negative aspects that I came across when reviewing the Sofirn IF24, it can be a pretty neat light. Those RGB modes could make for some neat party tricks (honestly, more likely just to keep my kids occupied)… just don’t have too much fun with that police strobe.

Buy your Sofirn IF24 here

Sofirn website discount code (25% off): IF24GMD20

1lumen selects and reviews products personally. We may earn affiliate commissions through our links, which help support our testing.