K&F Concept KF-150 Macro Ring Flash review: close-up flash for Canon and Nikon cameras

K&F Concept has been designing and manufacturing photographic accessories including tripods, filters and lens adapters since 2012 and has earned a solid reputation along the way. I’ve been impressed by some of its products, and I’m not the only one. The company won a Japanese Digital Camera Grand Prix award five years on the trot, the German Red Dot Product Design Award and other accolades.

Renowned for making good products at very competitive prices, K&F is a global player with distributors in 56 countries, including ‘Kentfaith’ websites in the USA, UK and Australia. The product I’m reviewing here is the K&F Concept KF-150 Macro Ring Flash, which is made in two dedicated options to suit Nikon and Canon cameras. Both editions aim to be among the best macro ring flash kits on the market, I’ve gone for the Nikon dedicated version.

K&F Concept KF-150: Specifications

K&F Concept KF-150: Price

Typical of K&F Concept kit, the KF-150 Macro Ring Flash is very competitively priced, selling for around $116 / £100 / AU$180. That’s just a small fraction of the price of own-brand alternatives like the Canon MR-14EX II Macro Ring Lite Flash at around $590 / £600 / AU$865 and the Nikon R1 Close-Up Speedlight Remote Kit at around $580 / £550 / AU$600, the latter also needing a Nikon SU-800 commander unit at $300 / £350 / AU$380, if your camera doesn’t have a pop-up flash to trigger it.

K&F Concept KF-150: Design & Handling

The design of the KF-150 is typical of macro ring flash kits. As such, it comprises two main components, joined together by a coiled connection cord. The control unit sits in your camera’s hotshoe, and the flash unit connects to the front end of your lens. Generally, you’d use this and similar flash kits for macro shooting but it can also be used for portraiture, where it creates signature halo catchlights in the eyes.

The control unit itself has a layout of controls that will look familiar to most photographers. There’s an illuminated LCD display screen, below which sits a rank of pushbuttons that include a strip along the top and four buttons configured as a 4-way pad with a button at their center.

I found the control system to be clear and intuitive. The Mode button enables you to cycle through the various TTL, Manual and Multi (programmable strobe) modes on offer. There’s a Lamp button for illuminating a pair of LEDs and a Ratio button – more on those later. There’s also a button for back-illuminating the LCD display, making it easier to see when you’ve gone to the dark side.

In TTL mode, the 4-way pad gives access to flash metering compensation of up to +/-3EV in one-third EV increments, as well as flash exposure bracketing. For manual power adjustments, I like that you can use the left and right buttons on the 4-way pad for full EV step changes, and the up and down buttons for smaller 0.3EV increments.

The flash unit sits at the end of a reassuringly thick, heavy-duty cable and, as I’ve mentioned, connects to the front of your lens. Naturally, macro lenses as well as regular lenses come with a wide range of filter attachment threads, so the KF-150 is supplied with a fairly generous collection of six attachment rings, catering to threads of 52, 55, 58, 62, 67 and 77mm in size.

A pair of pushbuttons on either side of the flash unit act as release/clamp catches for mounting and removing the unit from the attachment ring once you’ve screwed it onto your lens. It’s simple and effective.

Rather than having a single, complete flash ring, the KF-150 adopts a familiar layout of having two nearly full semi-circular flash tubes, one on each side. This enables you to use the Ratio button that I mentioned earlier to fire each side at different power settings. At the top and bottom of the circular array, there are two LED lamps, which you can configure with the Lamp button on the control unit to act as AF-assist lamps or modelling lamps, or turn them off altogether.

Unlike many recent flash units that run on a rechargeable Li-ion battery pack, the KF-150 runs on the time-honored fitment of four AA batteries. You could use alkaline batteries but recycle speeds after full-power output tend to drop off quite drastically after the first few flashes. I’d always go for a set of the best rechargeable AA batteries, which maintain relatively fast recycle speeds until they’re exhausted, and are then easily recharged again for further use.

While the batteries slot into the right-hand side of the control unit, there’s an additional flap on the left-hand side. Open this and you’ll get access to a PC sync terminal for triggering the flash via a cable, and a socket for powering the kit from an external battery pack.

The kit is supplied with a chunky, multi-lingual user manual and a tabletop stand, the latter of which also has a threaded receptacle for mounting it on a tripod. Everything’s wrapped up in a neat padded carrying bag, which has a loop on the back for passing a belt or strap through it.

K&F Concept KF-150: Performance

I’m not generally one to complain that a flash has too much power, especially if I’m wanting to bounce flash off high ceilings or distant walls with a regular flashgun. However, macro photography is more of a game of inches. I tested the KF-150 with my trusty Sigma 105mm f/2.8 EX DG OS HSM Macro, a lens that I’ve owned and loved for many years but which is now sadly obsolete. Even so, it’s still an excellent second-hand buy for Canon and Nikon cameras.

Like many macro lenses with a favored focal length of around 90mm to 105mm, the working distance of my Sigma between the front of the lens and the subject shrinks to around 6 inches at the shortest focus setting, for maximum macro magnification. The net result is that the flash unit mounted on the front of the lens is extremely close to the target. I found that even with the minimum flash power of 1/128^th dialed in for both sides of the flash unit, I generally had to set my camera’s sensitivity to its base regular value of ISO 100 and use a very narrow aperture of f/16 for well correctly exposed results.

Naturally, narrow exposures are often preferred for macro photography, so you can gain more than a tiny depth of field. Even so, the strong minimum power doesn’t leave a lot of room for maneuver. I also found that when setting the minimum flash power manually, there was often some variation between successive shots, sometimes by as much as 0.5EV.

Image 1 of 2

The claimed maximum power using both left and right tubes is Gn 14 (Guide number, ISO 100, meters). That’s frankly overkill for ultra-short-range macro photography, but useful for more generalized shooting. In my tests, the maximum output power equated to Gn 11, which is still plenty, shrinking to Gn 1.4 at the minimum 1/128^th setting for both sides.

In my tests, recycling speeds were virtually instantaneous when using a set of NiMH rechargeable batteries, at all power levels from 1/128^th up to 1/8^th power. Speeds slowed down to 1.3 seconds at 1/4 power, 2.6 seconds at half power and 3.8 seconds for full power, using the flash tubes on both sides in all cases. That’s pretty much what I’d expect, although K&F claim a faster 2.9 second recycling speed after a full-power flash.

What I didn’t expect is that the flash wouldn’t work in TTL mode with my Nikon Z6 II or Nikon Z fc mirrorless cameras. When I tried the flash with in TTL mode with both of these cameras, the results were massively overexposed, the KF-150 seemingly firing at pretty much full power all of the time. That said, compatibility is only claimed for a variety of DSLRs, comprising the Nikon DF D5500 D3200 D3100 D3300 D5000 D5100 D5200 D5300 D7000 D7100 D600 D610 D750 and D90, so perhaps I shouldn’t have been surprised. On the plus side, TTL flash metering certainly worked fine with my D7100 camera.

Image 1 of 2

K&F Concept KF-150: Lab Results

We test all available features for each flashgun that goes through out labs. To test power output, we used a Sekonic flash meter placed at a distance of one meter from each flashgun. We check the complete range of manual power settings, in one-stop increments. Based on a sensitivity of ISO 100, the figures correlate directly with the Gn (Guide number) in meters. The results are double-checked by taking shots of a gray card with the appropriate lens apertures and using the camera’s histogram display in playback mode.

We also check the speed with which each flashgun can recycle to a state of readiness, throughout its range of power settings, culminating in a full-power flash. We use freshly charged Ni-MH rechargeable batteries for this, or the supplied rechargeable Li-ion battery pack where featured in some flashguns.

The table below shows both the power output (Gn, ISO 100, meters) at each full EV step through the complete power range, from minimum to maximum output. The recycle speed in seconds is shown for the same settings. The tubes of both sides of the flash unit were used at the same power settings throughout the tests.

K&F Concept KF-150: Verdict

I found the K&F Concept KF-150 Macro Ring Flash simple and effective to use. It’s a shame that TTL flash metering doesn’t work with my Nikon Z6 II and Z fc mirrorless cameras, even though it works fine on my Nikon D7100 DSLR. That’s not a deal-breaker for me though, as I prefer to set flash power manually for macro photography, as well as for most other types of shooting.

The control unit is well laid out with a clearly labeled and intuitive interface. The flash unit has the versatility of two left/right tubes for different lighting effects, plus dual AF-assist/modelling LEDs. I found that flash output at the minimum power setting was a bit of a movable feast and rather inconsistent, but overall performance is very good, making the KF-150 a smart buy at the price.

Alternatives

The Neewer RF1 Macro Ring Flash has the same configuration of control unit plus flash unit with two semi-circular flash tubes and two LEDs. It’s available in dedicated Canon, Nikon and Sony versions, comes with six attachment rings and a set of colored filters which attach magnetically.