Sigma EF-610 DG Super

• Pentax P-TTL exposure automation
• Guide number: 61 (ISO 100, meters)
• Highlight panel
• Tilt: -1°, 0°, 60°, 75°, 90°
• Rotate: 0°, 60°, 75°, 90° clockwise; 0°, 60°, 75°, 90°, 120°, 150°, 180° counter-clockwise
• Zoom: 24mm to 105mm (35mm FF field of view), 17mm supported with slide-out diffusion panel
• Manual Flash: 1/1, 1/2, 1/4, 1/8, 1/16, 1/32, 1/64
• Optical remote master/slave (manual flash)
• Distance scale on flash LCD
• Red-eye reduction
• Modeling Light Flash
• Multi (pulsed) manual flash
• Power: 4 AA batteries, no option for external power
• Weight: 330 grams
• Size: (W X H X D) 77mm×139mm×117mm / 3.0in. X 5.5in. X 4.6 in

• Pentax P-TTL*,
• HSS (with P-TTL)
• Trailing curtain sync (with P-TTL)
• Auto flash zoom for both APS-C and 24x36 FF
• On-flash exposure compensation (with P-TTL) +/- 3 stops in 1/2 stop increments
• Pentax contrast control flash
• P-TTL Master/Controller/Slave per P-TTL protocols
• Dedication features consistent with Pentax AF360FGZ/AF540FGZ
• AF assist lamp

• On-flash auto exposure (auto-thyristor flash)
• Metal flash foot
• Pentax TTL (analog protocol, e.g. LX, Super Program, others)
• Correct output confirmation
• RF wireless
• External power supply
• Corded PC sync

• There is NO support for analog protocol dedication (M, A, P, and LX series bodies) or TTL (Super Program and LX) provided by the 4P shoe
• Digital protocol dedication and TTL ARE supported (AF film cameras, *ist D, *ist DS, and *ist DS2 dSLRs) as provided by the 5P shoe

The Sigma EF-610 DG Super is a full-size on-camera flash and has size, weight, and appearance similar to comparable Pentax models as well as competing 3rd-party offerings from other makers. The outer construction is plastic with a mildly rubberized surface. As with the Pentax AF360FGZ/AF540FGZ, the hot shoe foot is plastic with a wheel-type lock to secure the flash in place. Both tilt and rotation movements have locking buttons and detents at the angles specified above. Control and settings are done with rubberized buttons featuring a definitive action. An LCD display with switchable back-light is used to show current flash settings. Flash ready is signaled with a red LED with power being turned on/off using a slider switch on the back. A sliding plastic cover gives access to the battery compartment. The front of the flash has a transparent red panel covering a status LED and IR wireless RX components. Tucked into a space above the flash lens is the wide-angle diffuser and catch-light panel.

General
Despite the moderate price point, the EF-610 DG Super has been often mentioned as a possible substitute for the top-end AF540FGZ, so the bar for evaluation is set fairly high. After several years of use with the K10D and K-3,*** I have few complaints and remain quite happy with the flash. I have used all of its features, save one, that being as a wireless master. All features work as advertised and camera dedication is seamless. In short, I have not found myself wishing I had a AF540FGZ except, maybe, for three features, those being on-flash auto (aka auto-thyristor flash), correct output confirmation, and provision for external power.

Performance
A guide number of 61 (meters) places this flash at or near the top for on-camera P-TTL offerings. It has the advertised reach and despite its power, it is able to competently attenuate power down to the indicated 0.5 meters on the rear LCD at up to ISO 800 at f/2.0 when paired with F, FA, DA, or D FA series lens. Close-in performance is not quite as good with A-series lenses, though this is a problem with all P-TTL flash due to that series not reporting an estimate of subject distance for the preflash. Time to charge is generally acceptable (~5-6 seconds at full intensity) and instantaneous at 1/4 power and less, though not fast enough in general to allow use of any of my K-3's continuous drive modes (sets the camera to hickup).

Battery consumption has not been an issue in my usage, though I have not actually tested the spec'ed performance of 160 maximum intensity discharges on a set of NiMH cells.

Build
Some of the other reviews have criticized the lack of a metal foot, a trait shared with all Pentax-brand flash of the time. It has not been a problem for me, though I will concede that I might not feel the same way if I were subjecting the flash to rapid movements and frequent mount/unmount. The shoe and pedestal are similar to other flash on my shelf and average in stoutness, though not as beefy as metal-sheathed foot on my Yongnuo YN560III speedlights.

Another build item that has come under criticism is that of a flimsy battery door. I have not found mine to be fragile or difficult to close in a graceful manner, but will concede again that I might not feel the same if I were changing batteries multiple times per shoot and not being very careful while doing so. It should be noted that the same complaint has been leveled at the AF540FGZ. I would also note that, again, my Yongnuo units have a nicer door; whether they prove more durable is hard to say.

I have puzzled over the review below where the wide-angle panel did a self-destruct act. Mine operates essentially the same as those on my Yongnou units, meaning that it simply slides out and snaps down with no effort or need of supervision. That being said, the need to use it is fairly rare. The regular zoom function provides support for down to 24mm FOV with the diffuser intended to extend to 17mm. I did find a clue in the user guide that notes that if the panel does come out accidentally, the full zoom function will be disabled and will require Sigma service to put right. (Memo to self...don't force the wide panel...)

Ergonomics, Setup, and Controls
The flash is easy to mount and secure and adjustments for tilt and rotation are easy and sure. Sliding out the wide-angle diffusion panel automatically sets the flash zoom to 17mm. Balance on my cameras is good, with no clearance issues with camera, face, hands, or head. The on-off slider has good action and the status LED is bright and prominent. The LCD display has good contrast and in dim light the display illumination is quite good. In use, the lack of correct exposure confirmation in the viewfinder is regrettable in that one must chimp the exposure for cases where there might be some doubt and need to add flash EC rather than seeing immediately as the mirror comes down.

It is here that obvious flaw(s) surface. I will make a list:

• Buttons are small with labels that are unreadable in dim light (grayish red on gray?)
• The menu system is opaque with few clues as to what features are exposed for a particular screen
• Button function between screens is inconsistent
• Screen icons are not obvious as to meaning
• The user manual, while complete, is poorly organized and complicates the task of deciphering the screen and exposed options. In short, there is no screen/feature map or icon key.
• While the user manual states there is a correct exposure confirmation in the viewfinder and on the rear LCD, such is not the case with my combination of camera and flash
• The orientation diagram on the battery door is difficult to read in good light and impossible otherwise. While it is possible to determine orientation from the contacts on the door, having to do so is not what I expect from other than very cheap goods.
• As noted above, tilt stops are limited to 60°, 75°, and 90°. The lack of a stop at 45° limits usefulness with bare-bulb emulation diffusers such as the Sto-Fen Omni-bounce.
• As a minor notation, voltage is applied at the main hot shoe contact even when the flash is off. This is not a critical issue, but might be a minor consideration when used with other flash in a wired circuit.

The criticism regarding the controls and documentation is easily enough overcome with familiarity with the screens and button layout. Almost all P-TTL stuff is on a single screen. Where things get complicated is when trying to set up wireless P-TTL slave and one is back into the user guide. In other regards, here are a few more points:

• Despite comments on other reviews, flash settings are retained between power cycles, even if batteries are removed
• As a point of convenience, most on-flash modifiers designed to fit common Nikon and Canon models will fit the EF-610 DG Super
• On camera manual flash only works when the camera is set to M or X exposure modes. This is different than the built-in flash, but consistent with the behavior of the AF540FGZ. This is workable, but might limit its usefulness as a manual flash.
• Remote P-TTL, contrast control, and Normal slave functionality works as advertised, but normal slave cannot be triggered from the build-in flash on my K-3 when that flash is in P-TTL mode (no SL2 mode). Again, usefulness as a standalone manual flash is compromised.

• Powerful
• Reliable
• Performance in general
• Excellent P-TTL support
• Excellent compatibility with Pentax digital flash dedication
• Full-featured
• Generally high build standard
• Moderate price

• No longer current Sigma product despite being currently offered for Nikon, Sony, and Canon systems
• Beastly and cruel controls, LCD settings screens, and matching documentation
• Lack of auto flash mode
• Would benefit from metal flash shoe
• Lack of working correct exposure confirmation signalling
• Details of battery door implementation
• No option for external power
• No option for PC sync

Despite the list of shortcomings, this is still a great flash and worthy of consideration by anyone put off by the high prices (new and used) of the Pentax flashship flash products and the equally high prices of the flagship Metz product. Whether the Sigma EF-610 DG Super is a better solution used or NOS than options from Yongnou, Godox, Cactus, Bolt, or relabel to Metz is hard to say, but if you find one in good shape and at good price and have been needing a full-featured P-TTL flash as primary flash or part of a multi-flash set, it should be worth considering.