The Cactus AF 50 is the latest TTL flash unit from Gadget Infinity. This unit has many advanced features that are normally only found in manufacturer specific flashes. 

 
It comes in five versions: Nikon, Canon, Olympus / Panasonic, Pentax and Sony Alpha / Minolta. The AF 50 in general has a very solid feel to it and is about the same size as a Nikon SB600. On the front of the flash is the slave sensor and an auto focus assist red light. The battery compartment is on one side with the wireless sensor on the opposite. The unit also has a built in diffuser and bounce card. 

One of the more interesting physical feature is the mounting foot. It has a push to lock fastener that does a great job of keeping the flash firmly locked into place. The flash head has the ability to both bounce ( 0-90 degrees ) and swivel 180 degrees one direction and 120 degrees the other.
One the back of the AF 50 you will find the control panel which consists of two buttons and two switches. You have one switch for the power and another for slave mode selection. The way the slave mode is set up is a bit lost on me. When selected the slave mode will skip a selectable amount of flashes ranging from 0 to 9 before it fires. 

Now, I can see where having the ability to optically fire from another light source is a great thing to have. There are typically two modes needed to use an optical trigger effectively. One mode where the flash ignores the cameras pre-flash and one that it does not and fires right along with it. The slave function on the AF 50 allows you to skip all the way up to nine flashes before it fires.

 There might be something that I am missing about this feature and if there is please feel free to let me know.




Also on the back of the control panel you will have two buttons: Mode and Zoom. The mode button will allow you to scroll through the functions of the flash like: TTL, manual, STTL then it will return to TTL and the sequence will start over. Now this one button is used to set the mode and also the manual power output, select wireless groups and channels. When you are scrolling through the mode options make sure to take your time with it. If you pass over what you are looking for then you will have to go all the way around again. The AF 50 modes are: TTL flash mode The TTL mode is the default mode of the flash unit. 

When you power the unit on it will be in TTL mode. This flash does a great job in TTL mode. I have found that in just a few instances that it was a bit over exposed, but not to the point that it is a concern. Manual flash mode. Once in manual mode you can set the flash output over six power levels (1/1, ½, ¼, 1/8, 1/16 and 1/32.) The LCD will display distance and exposure information for what it thinks will be the correct information. You can use it to get a rough idea of have far you need to be from the subject to obtain correct exposure. STTL mode 

 After manual mode comes STTL which is the AF 50's version of wireless flash control. I have the Nikon version of this flash so this is the mode I would use for Nikon's Creative Lighting System. The AF 50 is completely compatible with CLS and integrates into the system with out any problems. 

This flash holds it's own against the Nikon SB600 and easily keeps pace with it. The channel and group selection is a bit cumbersome. As mentioned before you have one button to set all of your modes and their controls, so if you scroll past what you want to select then you have to go all the way through once again. Also keep in mind that if you are using this flash in the CLS system every time you power it off and then on again you have to go through and set the mode and select your channel and group. 

As you scroll through the STTL mode you will see the channel and group setting as follows: 1a, 1b, 1c, 2a, 2b, 2c, 3a, 3b, 3c, 4a, 4b, 4c and then you will return to TTL. Once you have the corresponding channel and group set the AF 50 will function just as a Nikon CLS capable flash would. You will have remote power control and my personal favorite high speed sync. So, you will be able to get your shutter speed up to 1/8000 of a second as long as your camera is CLS compatible. The second button on the back control panel is the Zoom button. This button will control the manual zooming of the flash head. It has seven zoom positions which are 24-28-35-70-85-105mm. 

When powering on the flash unit the zoom will default to the 35mm position. If you are using a zoom lens that sends it's focal length data to the camera the flash will adjust to its relative position. When you zoom your lens from 28-70mm the flash head will follow the zoom to 70mm. This is a very nice feature that helps keep your on camera flash more consistent when using a zoom lens. 

 Another great feature is the AF 50's power saving function. If there is no communication between the camera and the flash for three minutes then the flash will go to sleep. To wake up the flash unit all you need to do is press any of the flashes buttons. 

 The rear LCD supplies all the information that you will need plus some. All of the usual suspects are there like power settings, mode indicator, zoom position, ISO and f/stop.




As I have been testing this flash it has yet to let me down while shooting. The body does not feel cheap and its exposure is consistently right on in TTL. 

Overall the only thing that I would like to see changes is the settings navigation. It might make changing modes and power levels faster if you could cycle through just the modes themselves by pushing and holding both buttons and then once you had selected the mode you want then use the single scroll button to select the setting. Other than that this flash is pretty good.

If you are in the market for another TTL or CLS compatible unit you should take a close look at the Cactus AF 50. You will find a lot of great features at a price around only $150.00 you really can't go wrong. For more information on the AF 50 check out gadget Infinity's web site: gadgetinfinity.com