The Canon 600EX-RT with built in radio system has certainly been a breakthrough for wedding and event photographers, but there are a couple of fairly big problems many people run into when trying to put together a flash system including the Canon RT flashes.
The main issue – is with Canon RT being a closed system, there is no way to conveniently fire any other manual speedlites or studio lights, which many wedding and event photographers need to use, or at least combine in their set up at times. This means a second transmitter needs to be connected to the camera in some way, usually either by connecting a cord to the cameras PC sync port, or using a radio transmitter with a Pass Through Hotshoe (which you can then mount the flash on top). Neither solution is really convenient, or ideal for serious use, and they both often end up in more problems eventually.
The second whammy – is the Canon 5D MKII (still one of the most popular camera for wedding work) does not allow full function with the 600EX-RT system, so you can’t access the newer group control where you can mix ETTL and remote manual groups. This is a real hassle as many people want to use ETTL for their on camera flash, and remote manual off camera for background lights etc (where you want to keep exposures consistent).
The third issue – is the lack of Second Curtain Sync function for remote off camera flashes. Not so critical, but still a considerable drawback .
The new Phottix Mitros+ radio based flash provides a solution to these problems. Because unlike the 600EX-RT, the Mitros + integrates with a number of Phottix’s TTL and manual receivers, allowing most studio and manual speedlites to be fired. As well as most of Canon’s EX flashes (not just the 600EX-RT) when connected to Phottix Odin TTL receivers. The Mitros + can then be mounted directly and securely on the camera hotshoe, with no other transmitter units needed on the camera.
And the Mitros + provides full function with most Canon DSLR cameras (not just 2012 onward like Canon’s system) allowing ETTL and remote manual groups to be mixed. And Second Curtain Sync is also supported off camera.
So the release of the Mitros + is really quite significant, as its not just a cheaper 3rd party option to the Canon system, but also a solution to some large shortfalls in Canon’s closed system (which if history is anything to go by, are highly unlikely to ever be addressed with separate receivers).
I’m not sure if many current 600EX-RT flash owners will be selling up their significant investment to switch to the Mitros + just yet. But many people looking to buy into a professional flash system now will be seriously weighing up the options. And I guess its really going to come down to whether there are actually any major disadvantages with the Phottix system which are possibly going to effect their needs.
+ Manual receiver options for firing other manual speedlights and studio lights.
+ TTL Odin receiver option for firing most Canon EX flashes (not just the 600EX-RT).
+ Reliable direct flash on camera mounting, without extra transmitter or pass through hotshoe.
+ Quality reliable manual Strato II receivers from just $50.
+ Quality long range Atlas II manual receivers allow up to 350 meter range.
+ Full function (mix ETTL & remote manual) with most Canon DSLRs (not just 2012 models onward).
+ Second Curtain Sync function for off camera flashes.
+ Remote Zoom function for flash heads.
+ Range between Mitros + units reportedly quite long (yet to be confirmed).
+ USB port for firmware udates.
+ Battery level indicator.
+ memory for 3 user profiles.
+ 3.5 mm sync jack.
+ Can be fired by fully manual Strato II transmitter (which has 4 quick select groups).
+ Cleaner simple LCD screen interface (subjective).
+ Power – similar direct, bounced 600EX-RT is up to around 1/2 stop more, depending on flash zoom etc.
+ Recycle time – similar, but current Mitros has heavier overheat protection (may be revised).
+ 20 – 200mm zoom (vs 24 – 105mm for the Mitros +).
+ 5 groups (vs 3 groups for the Mitros +).
+ Highly dust and weather sealed.
+ Flash recycle ready feedback on the transmitter from remote flashes.
+ LCD screen backlight color option of green or orange (can be used to indicate master and slave units).
+ Gel holder, with color and exposure information transmitted to the camera.
+ Larger more detailed LCD screen (subjective).
+ No adapter needed for external battery pack socket (as Mitros + requires).
+ 15 channels + an auto channel option (vs 4 channels for the Mitros +).
+ Full Canon 1DX compatibility (Odin and other 3rd party radio systems still have some issues there).
+ Paid repairs are possible at local Canon service centers.
So the 600EX-RT does have some other extra features/refinements as well (as you would expect from a top end Canon flash). But most of these are probably not going to be desperately missed by most people.
As far as the radio system and range and reliability go, from previous experience with the Odin system I have no doubt the Mitros + will match (if not exceed) the Canon system there. (I only have the current non radio enabled Mitros flash and Odin system to go by at this stage).
There has been some discussion about this recently regarding the current Mitros flash, and I have been testing this a lot over the last few days (its really taken that long, as the flash has to be left to cool down completely between tests).
And the current Mitros certainly does have some heavy recycle slow down for thermal protection. The flash has never actually gone into thermal protection mode, but that is because they recycle times are already slowed down considerably before the flash ever gets a chance to heat up that much.
Phottix are reportedly already looking into this, so there is even a possibility this may be revised by the time the Mitros + is available (current Mitros have USB port, so firmware updates could also be possible there). It really depends on how fast, and at what power level you shoot, as to whether this would be an issue or even noticed. But in testing I found a simple way to bypass the slow down if needed is to simply switch the flash off and back on quickly (or release the battery door a little quickly), and the flash is good to go again at full recycle speed.
To give you an idea of the difference, the 600EX-RT will do 40 full power flashes in pretty quick succession with an external battery back –
By that stage the flash head would really be close to smoking hot, so its good that it does shut down if you actually pushed it that hard. In comparison the Mitros would not even do half that many shots before the recycle time starts to slow down to 5 seconds, and then successively longer as you keep going (even with an 0.7 second capable battery pack).
So if you push your flash hard, that would be the main practical difference I can see currently see between the two flashes. But as mentioned this could possibly even be revised before release of the Mitros + anyway.
If I may have missed any advantages you may be aware of with either flash system, please let me know. Thanks!