A little over a year ago I wrote a post about the Viltrox Focal Reducer for EF lenses on EF-M bodies that supported full AF and camera connectivity, a 1 stop speed boost, as well as EXIF data modification for focal length and lens speed. I even did a video on it video link here. That was a solid device, well made, and optically very good. I also admonished Metabones for not having such a device at all. Metabones is the company that really brought this tech to the still photography market. They have a massive catalog of the craziest adapters you can imagine yet did not have the relatively easy Canon EF to EF-M speed booster. I say relatively easy because they already had one for EF to Sony E mount which has the same physical mount size and back focus. The electronics to convert EXIF data was present they just had to create proper electronic connection for Canon.
Well things have changed, and Metabones introduced a speed booster to mount full frame EF mount lenses on an EF-M mount camera with a full stop of speed and the full EXIF conversion recently along with a version for Canon R mount cameras. Metabones is the premier manufacturer for this type of device. They are are engineered in Canada and contract with Caldwell Optical in the USA to create the best speed boost focal reducers on the planet.
I decided to upgrade my Viltrox unit into a Metabones unit. Here is what I found: the Metabones unit feels even better built than the Viltrox. Mind you, the Viltrox was a solidly built piece of gear. The Metabones unit uses clearly superior materials but is about 25% heavier. Optically the Metabones unit is noticeably superior across the frame. The Metabones unit also is quicker to acquire focus than the Viltrox which has a bit of a stutter at the end of the focus acquisition. The Metabones unit for some strange reason does not convert EXIF data on lenses that are f/1.4 or faster. The Viltrox converts f/1.4 to f/1.0 but does not show EXIF data for f/stops faster than f/1.0. So it also converts f/1.2 to f/1.0. Both the Metabones and Viltrox units support actual speed boost to f/0.85 but the EXIF data will not match the actual speed boost values on super fast lenses. I hope Metabones will create a firmware patch to convert all EXIF data, it seems odd to have the fast glass not get the conversion on EXIF especially since they are converting the focal length on the fast glass, just not the speed.
I am delighted with the Metabones unit with my only complaint being the EXIF discrepancies on the super fast lenses. Metabones Speed Booster EF to EF-M Ultra is a 0.71x focal reducer with a one stop speed boost. The Ultra optics are absolutely top drawer with the high refraction tantalum glass by Caldwell Optical in the USA. This device is more than double the price of the Viltrox. Metabones list price is $479 versus less than $200 for the Viltrox. The Metabones is noticeably faster in its operation and sharper. Where the Viltrox is very good the Metabones is excellent.
One area I will be using this device is for some astro-photography, gaining an extra stop cuts down on exposure times which can be measured in minutes rather than seconds. if you are curious about the math behind these speed boosters check out my article “Fidgeting with Focal Length.” I have a few images made with the Metabones unit below these were just a quick test.
In other news, some of you may have noticed a pleasant side effect of Canon’s push towards new EOS R mount lenses. Many of the EF L series lenses are becoming more affordable at camera shows and on Ebay. The bottom line is that there is a fair amount of photographers moving to the EOS R system from the EF system and that means some lenses are being exchanged for newer and typically better RF glass. Anytime you increase supply without increasing demand you are headed for lower prices. That seems to be the case on lenses that have a direct R mount equivalent as well as some lenses that have indirect R mount equivalents. The 24-105 L Mk I is available used for well under $500 these days sometimes dipping into the high 300s, and that is still a very good lens. Even the Mk II version has softened up a bit on the used market fetching $600-$700. The RF 24-105 L is noticeably superior, but it will set you back $1100. The Canon EF 85/1.2 L is also a fair value on the used market. Be advised that the Mk I and Mk II have the same optical formula but the Mk II is nearly twice as fast on AF and that lens is notoriously slow focusing so paying a premium for the Mk II is still sound. The Mk I lenses can be found as low as $600 and the Mk II models are fetching closer to $900. This lens is still available brand new from Canon for nearly $2000! RF bodies are the future, but EF glass can be easily adapted and with no noticeable side effects. These excellent EF L series lenses are a great value.