Irix 11mm f/4 lens, first impressions
I loved the wonderful wideness of my 14mm Nikkor, but for wide landscapes and seascapes with straight lines, the mustache distortion and flare issues sometimes ruined or restricted the best composition of my images.
All wide angle lenses are plagued with various distortion issues; it's a matter of finding a lens whose issues you can predict and work around or correct. The Nikkor is a fine lens for many uses, but it's a bit disheartening when you compose a beautiful seascape only to discover later that there is an uncorrectable curve in the ocean's horizon line.
Out of a handful of initial images I made with the Irix 11mm (Firefly version), I saw no ghosting issues when pointing into filtered sunlight, and the Irix's barrel distortion was both unsurprising and acceptable for this wide a lens. It also looks to be easily correctable.
1) Irix 11mm f/4 Firefly on Nikon D610. Pretty well balanced barrel distortion on the bottom, and mostly on the top left of the frame. Distance was about 1.5 feet. F/6.3 Some darkening at the corners - not an issue for me.
2) Irix 11mm f/4 lens at f/9. The sun was filtered behind the leaves, but I still expected some ghosting. There was none. That doesn't mean it won't show in some situations, but I feel pretty certain that the Nikkor would have ghosted here.
3) Irix 11mm f/4 at f/8. Nikon D610. Shooting vertically with a lot of lines in the photo. Nothing unexpected here.
4) Irix 11mm f/4 at f/9, closest focus of 0.9 feet (0.257 meters). I'm surprised at the fairly shallow depth of field, but I like the way the background blurs.
5) A vertical shot showing barrel distortion. I don't find this terrible for an 11mm rectilinear lens. My focus was off in this one too, so I gave the image a little extra sharpening. Notice how the sharpening intensified the chromatic aberration, which I had not corrected in post processing.
6) Oliver preening himself.
It's important to note that this is a manual focus lens and the barrel turn from closest to farthest focus is over 4.5 inches. Being that this is an f/4 ultra-wide lens, I wasn't surprised to find my Nikon D610 having a hard time showing me a precise point of focus at the farther range. On many occasions, I had to use the focus confirmation dot and my own eyes to get it just right. For some scenes, it seemed easier to just set the focus by estimating the distance. There is a hyperfocal scale on the barrel. The Irix is a G-type lens with no aperture ring. It also has a ring on the barrel that will lock the focus in place, though focusing is so firm that I can't imagine why this is needed.
The lens has a fair amount of chromatic aberration, which should be easily correctable in post processing. You may see it though, if you use jpeg images straight from the camera. This is not unusual for an ultrawide lens.
The Irix comes in a metal box and is supplied with a built-in hood, two rear lens caps (one is a spare), a plastic lens cap/cover, and a soft pouch to protect the lens from getting scuffed up in your camera bag. The Firefly version weighs 25.8 oz (about 731 grams).
I'm going to have a lot of fun using this lens.