This circular form factor is pitched as an improvement over a conventional rectangular cobra-style hotshoe flashgun for a couple of reasons: more natural-looking beam shape and the option of fitting magnetic accessories to the head.
Should your next flash have a round head? Here are a few reasons why not.
Round flashes are more expensive
Features such as manual power control, TTL, high-speed sync and built-in radio are all but standard in mid-tier camera flashes (and indeed studio lights) nowadays. Lithium batteries are increasingly common. If you want all that and a circular fresnel then you’ll typically find yourself paying a premium over the equivalently-specced conventional flash.
For example, the Godox V860II lithium-ion speedlight is priced around US$179, versus the Godox V1 round flash at $259. Both have the same Godox X-system wireless functionality, have near-identical user interfaces and come in versions for a range of camera brands. Plus, if you want to save even more money then you can opt for the cheaper V850II, which at $139 has the same battery and radio capabilities as the V860II but is manual power only.
Meanwhile, Profoto’s pricing is well known, with the current A-series model retailing for over $1000. The only rectangular flash at this price point is the new Canon Speedlite EL-1, but that’s an exception, not the rule. You can still buy a 600EX II-RT for half that amount.
For another within-brand comparison: Yongnuo’s oval-head YN650EX-RF is set to cost $140 (though it isn’t actually out yet), whereas their top YN686EX-RT lithium flashes are $163. However the manufacturer offers cheaper lithium flashes such as the YN720, YN860Li and YN560Li for closer to $100, whereas there are no cheaper round (or oval) options available.
Round flashes are less efficient
On-camera flashes are rectangular because camera film and sensors are rectangular. With an on-axis light source, the light need only fill the scene exactly to the edge of the frame; anything that falls outside is wasted photons. But if you’re using a round flash on camera then you’re trying to fit a round beam into a square (or rectangular) hole. You can zoom in the fresnel for a tight beam and have vignetting in the corners, or zoom out for a wide beam and have light spill out the top and bottom of the frame, never to appear in your final photograph.
The Godox V1 (and Profoto A1) are less bright than the V860II. Despite the V860II being cheaper, having a smaller battery (2000 mAh vs. 2600 mAh) and being brighter at full power, the battery life is still longer, at a claimed 650 full-power pops for the V860II, compared to 480 for the V1.
Why pay more for less?
Round flashes are bulky
Bear with me on this. A round-head flash is similar weight to its conventional counterpart (e.g. the specified weights of the V860II, V1 and A1 are approximately the same).
But if you’re using a compact mirrorless camera then you might prefer a smaller flash, such as the MeiKe MK320, Nissin i40 or Godox TT350. There are no small mirrorless-friendly flashes with round-heads, yet.
Round flashes need all new accessories
One of the touted benefits of round-head flashes is the edge of the fresnel is magnetic, so you can stick on gels, grids, snoots and diffusers with ease, and even stack them in some cases. But you can already get magnetic attachments for ordinary flashes in the form of MagMod or Hähnel’s Module system. And whereas you can augment this with DIY modifiers using Velcro or stubby holders, it’s harder to make your own accessories for round-head flashes without them slipping off.
Unless you do a DIY modification to your Godox S adapter, you need to buy the new Godox S2 (not a lot of money, to be fair) for a round head flash to fit in it. Similarly, if you have a dedicated speedlight softbox like an Aurora Firefly, the rectangular opening won’t accept a chunky A1/V1 head, so the company is now offering round-head-specified versions of the same softbox.
If there’s a cool round-head accessory that you want to try out, you don’t need a round-head flash to use it; adapters such as the Godox S-R1 (or Falcon Eyes SGA or Triopo equivalent) will turn any ordinary flash into a round-head flash, with the option that you can remove the adapter for transport and storage.
Round flashes offer no advantage on-camera
Direct flash, when matched to your focal length, should fill the frame. If you were to zoom the fresnel all the way in, you might see the edges of the beam, but you’d have on-axis flash and vignetting, neither of which is a good artistic choice.
Oh, but you’ll be tilting or swivelling your flash, and not firing it straight-on, you say? Well, your bounced round flash will make a lovely smooth pattern… on the ceiling or the wall behind you, in which case the shape doesn’t really matter.
“None of that matters though because I’ll be using my flash off-camera, the way nature intended,” you exclaim. Then why not buy a proper off-camera flash?
What do you think? Share your thoughts in the comments below.