Mini review of the FotodioX Pro Canon EF to NX adaptor with iris on the NX1

I have this one: FotodioX Pro

It is tight on the camera, making the aperture adjustment ring a little difficult to turn. But I did become accustomed to it pretty quickly. One thing for sure is that it is very well built out of brass and stainless steel. It is very important to make sure the red dots are lined up properly, both between the camera body and adaptor, and between the adaptor and the lens. This puts the lens at the proper flange distance for proper focus.

Before I bought this adaptor, I posted a question here to previous owners about any vignetting with the adaptor's iris behind the lens' rear objective. Since I really didn't get a negative response, I decided to find out for myself. I figured, even if there was vignetting, I could use the adaptor wide open. I have now tested the adaptor with Canon EF mount focal lengths of 12mm-400mm (in full frame speak) on my NX1.

The quick verdict is: it works. Here is an image at 400mm (616mm on the NX1) with the Canon EF 100-400 L and the adaptor's iris wide open (the image, like all others in this thread, are SOOC):

Canon 100-400mm L at 400mm (616mm on NX1) with adaptor iris set to wide open.

Although the adaptor's iris ring is declicked, allowing smooth transitions, it does have nine markings on the barrel from wide open to minimum opening. Here is another example of the adaptor wide open, this time with the Sigma EF mount 12-24mm rectilinear lens set to 12mm:

Sigma EF mount 12-24mm rectilinear at 12mm with adaptor iris set to wide open.

At both extremes of my tests, 400mm and 12mm, when the adaptor's iris is wide open, there is no vignetting. And focus is easily obtainable using the manual focus aids of the NX1.

Now let's stop down the adaptor's internal iris to see what happens. We'll start with the 12mm focal length first. Going through the first five of the nine markings on the adaptor's barrel, the vignetting is well controlled, building slightly at each step. Depth of field also increases nominally at each marking. At the sixth step though, here are the results:

Sigma EF mount 12-24mm rectilinear at 12mm with adaptor iris set to the sixth of nine markings.

Vignetting is now becoming very apparent. And then it gets very bad very quickly until at the final marking, here are the results:

Sigma EF mount 12-24mm rectilinear at 12mm with adaptor iris fully decreased.

So at wide angles, the adaptor is very useful over half the range of its internal iris.

Now we'll go to the opposite extreme, the 400mm lens results, with the example of the iris being wide open already shown above. With telephoto lenses, unfortunately, it starts to not look pretty much quicker than for wide angles. Here are the results at the third marking on the adaptor:

Canon 100-400mm L at 400mm with the adaptor iris set to the third marking.

By the time the ninth marking is hit, here are the results:

Canon 100-400mm L at 400mm with the adaptor iris fully decreased.

In some world, this could be very artistic with the right subject. But certainly not in every day use.

So as you may have surmised, the adaptor's internal iris is reasonably useful for wide angle lenses. Moderately useful for normal range lenses. Less useful for shorter telephotos. And of very limited use for long telephotos. So, as I previously said, the adaptor does work, as long as these limitations are taken into consideration. One thing though is that the sixth to ninth iris settings are mostly totally unusable, except possibly for artistic pursuits.

Since I assumed before buying the adaptor that this would be so, the reason for my question in the prior thread, I'm OK with the limited iris. My test results for the working irises at each focal length came out very well.

I hope everyone contemplating using their Canon EF mount lenses on their NX1 find this useful.

Ed