In the lenses, there is an iris. Well in the objectives, there is Irix: Thought in Switzerland, made in Korea.
Update: originally written in 2016, this article was updated in April 2020. The updates are in paragraphs on a blue background.
This is one of my discoveries (it is not a novelty or a scoop, I admit) from my passage, a little quick, at the Paris 2016 Photo Fair. TH Swiss AG offers Canon, Nikon and Pentax mount lenses, available in two finishes:
- Blackstone
- Firefly.
there are two Irix lenses: 11mm / f4.0 and 15mm / f2.5. A 45mm / f1.4 is currently on the market.
There are 6 Irix lenses divided into two ranges; photo and cine:
Cine
- 11mm T 4.3
- 45mm T 1.5
- 150mm T 3.0
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Careful construction
What is obvious when you approach an Irix lens, and even more when you take an Irix lens in hand, is the construction. It is neat, well finished and well assembled. Each lens is available in two versions, reflecting a level of finish.
- Firefly: Aluminum body construction and case in composite material. Anti-slip focusing ring. Standard white marking. Supplied in a soft case.
- Blackstone : Aluminum body construction and magnesium housing with anti-scratch treatment. Metal serrated focusing ring. White marking sensitive to UV. Comes with a hard case.
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Construction is good, but the most important thing for a goal is what you see inside.
A low distortion rate
With focal lengths of 11mm and 15mm you can expect a high distortion rate, not with Irix. Thanks to a complex and ingenious optical construction, the distortion rate for the 11 mm is 3.13% on the edges and 2.00% for the 15mm. Very very low values for this type of lens. The result is an image that is very easily corrected with software like DxO OpticsPro.
The Irix lenses are manual focus and to avoid touching the focus ring by mistake, Irix has developed the “Focus lock” system which allows the ring to be locked. On the Blackstone versions, the white marking is reactive to UV, ideal for night and astronomical shots.
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For the price, it takes around 500 € for the 15mm in the Firefly version and around 700 € for the 15mm in the Blackstone version.