Hey all, I recently bought an STF-22 to pair up with my Panasonic 45/2.8 and EM5 and thought you all might like to read a bit about it since it's a bit of a rare bird. I'm a long time Canon and Four Thirds shooter, and until recently used a Canon 100/2.8 and MT-24EX on my 5D2 for macro. It was a good kit, but very heavy and the OVF (and poor Live View) made framing at odd angles painful. I was happier with my EM5 and 45/2.8 and was getting by with my FL-36R on a homemade flash bracket, but I really missed the convenience of a twin flash. They're easier to handle than a heavy hotshoe flash hanging off the end of a long lever and they give a ton of control over lighting. Here's a pic of my new kit. EM5 with HLD6 grip, Panasonic 45/2.8 Macro, a 46->67mm step-up ring, and the STF-22 with the diffusers fitted: First impressions, the flash itself is very large. About the size of an FL-50R or 580EX, complete with (strangely, I thought at first) a rotating head. It's heavy like a full-size flash, too. The flash knobs on the back are "backwards" to me, like all Olympus flash equipment. Turning the wheels clockwise DECREASES FEC. This drives me NUTS. Ratio control can give you up to 8:1 bias in third stop increments, or turn one head off entirely. Having a wheel for the ratio control is handy, I will say. Much nicer than the buttons on my MT-24EX. The flash has assist lamps built into the flash heads. Coming from using the Canon MT-24EX where the lamps were external to the flash heads this is very nice; my diffusers often blocked the lamps on my Canon flash, but I don't have that problem with the STF-22. You can also configure the lamps to stay on for a full minute at a time. MUCH nicer than the Canon lamps, which somehow always stayed on for exactly one second less than you needed them. I miss the Canon's ability to turn the lamps on with a double-half-tap on the shutter, but I'll take this trade-off happily. Moving to the body of the unit, the cables connecting the body to the head are long, very thick and not very flexible. This has been my biggest complaint shooting with the flash. The cables constantly get in the way when reframing for a vertical shot. You have to tilt the flash body up to rotate the heads to 10 o'clock and 2 o'clock, or the cables block you from rotating the heads. And tilting the body up makes the unit top-heavy. This probably wasn't as big a deal on a big body like the E-3, but on the EM5 it makes it a bit awkward to shoot in portrait orientation. The STF-22's ring has a 67mm screw that you can attach directly to a lens. My 100-300 is my only lens with a 67mm thread. I do most of my macro on my 45/2.8 so I bought a 46->67mm step-up ring on eBay, which was the only place I could find one, except for a very overpriced one at B&H. Once tightened securely to a lens you notice the ring is a two-piece design. The part on the lens remains fixed while the part the heads connect to rotates. There are stops at 90° increments, so you can quickly reposition the heads between landscape and portrait. The ring has some friction that keeps it in place between those increments if you don't move it too violently. Permanently attached to the ring are the two flash cold shoes. These can be repositioned by squeezing and turning them along the ring, and there's a button on the front to release the head from the ring entirely. You could attach an FL-36R to one of these shoes if you are clinically insane. The heads themselves are very nice. They have a flash tube and four LED lamps inside and a groove to slide a (supplied) diffuser in front of the head. They have plenty of tilt control and even rotate. They have a tripod thread too, in case you need to use them for studio macro shooting (although the length of the cords would limit your positioning). That's pretty much it for the unit itself. How is it to use? Great, with some caveats. First the negatives: 1) I had a hard time guessing how the flash would meter. I got a lot of exposures 1-3 stops under what I expected, and I wasn't sure why. I don't know if it's the flash or me. I need a lot more experience to make that judgment. 2) The flash cables are sometimes infuriating. They are always in the way, and left me wishing Oly had a wireless system like Nikon's R1C1. If I could pay an extra $200 on top of this unit's cost for wireless, I'd do it. 3) The unit is fairly heavy. It's still much lighter than my Canon kit overall, but the flash itself isn't any smaller. The flash recycles very quickly, so I wouldn't mind having a lighter unit with two AA's instead of four. 4) The dials being "backwards" drives me crazy, just like my FL-36R. I've been using Oly flashes for years and I just can't get used to it. I really wish Oly had given us the option to toggle the direction. 5) Not a complaint about the STF-22, but I can't miss an opportunity to whine about the EM5's lack of ISO100 and the pain that it makes shooting macro in daylight with a flash. I sure wouldn't mind a faster sync speed! Now that the negatives are out of the way…. I really like this flash! Let me count the ways: 1) The diffusers Just Work; I get good diffuse light at 1:1 all the way out to non-macro distances. I doubt I'm going to have to screw around with a bunch of add-on diffusers like I did with my Canon kit. WONDERFUL. 2) The flash has plenty of power. Follow-up shots for timid bugs are no problem so long as you turn off LCD review on the camera. It is quick to recharge even shooting indoors. Shooting ISO200 f/16 in low light at 1:1 the flash just keeps going and going at its maximum 2fps-ish. 3) Like I said earlier, the assist lamps are awesome. Plenty bright, and I've got them set to stay on for a long time. Drains battery a bit, but I've got a bunch of AA's. 4) Removable flash heads give me tons of control over the light. I went out shooting at a local botanical garden and it was handy to remove one flash head and position it by hand. I put it behind leaves to backlight them, or just out of frame and to the side to give a strong sidelight to add more definition to edges. 5) The heads are fairly easy to reposition around the ring, and with the generous tilt and rotation of the heads I never had any problems getting the light exactly where I wanted it. (Well, when the cables weren't in the way). 6) The flash heads have a wide throw, at least with the diffusers mounted. Out of habit when I got the STF-22 I would constantly reposition the heads when changing focus distance, as the MT-24EX had a very narrow throw and required careful head positioning. Turns out the STF-22 spreads the light around enough that I only had to touch the heads if I was shooting a foot away or more. This made my life a lot easier. Overall I'm very happy shooting with this new kit. The STF-22 is a good performer, but that's only half the story. The EM5 is a great macro camera, with its bright tilt LCD, usable AF at macro ranges (I used AF a LOT, which I couldn't do with my 5D), and huge tonal range. And the 45/2.8 is a great lens, with a nice working distance, great build quality (important with a flash hanging off it), nice smooth focus ring, and excellent IQ, all in a tiny package. The kit dwarfs my GF3 and 14/2.5, but it's still a ton smaller and lighter than my old Canon kit, which is great news for my wrist, which was often sore after a day's macro shooting at weird angles. I wish I had it years ago. Here's some pictures from my first day out shooting with the STF-22: The EM5's quick 2x crop is handy here to nail focus: This is a heavy crop. The EM5 holds detail at 100% better than my EP3 does, and pulls back an oversaturated color channel with much less color shift: This one has a flash head handheld just to the left of the frame. AF makes this a lot easier: I repositioned the left flash head below the lens here to shoot into the flower: Outdoors the flash is useful to add add some definition to what would have been flat lighting in the shade: The twin heads can help keep harsh directional shadows away: The EM5's LCD makes shooting bugs easier. I can watch the camera to make sure I don't bump a flower with the flash or shade the sun and scare my subject away: The flash heads aren't too harsh at a distance: Hooray for live view! I wouldn't go 1:2 with these guys on my 5D! See, flash lighting can be nice and soft. Who needs ambient? This guy was TINY. And timid. And very active. I don't know if I was at 1:1, but I was close. I wouldn't have gotten this shot before he escaped with my 5D's OVF: Bee hunting is much easier with live view. I found touch screen AF very handy shooting bees: Shooting water droplets everybody knows you're shooting with a twin flash! Thanks for reading! If you have any questions about the STF-22 don't hesitate to ask! There's not a lot of info out there, so I'm happy to help if I can.