In today's competitive market of photo content, professional photographers differentiate their works using special equipment and techniques. "Camera lens" are recognized as the most important craft in image production, so on an approved approach to access unique perspective in a photo is relied on glasses with particular character like extreme focals (ultra-wide or super-tele lenses). On the extreme long focal, the challenge both on size and weight is always presence for any photographer who wants to carry the equipment on long distances. This problem is well addressed by Tokina lens manufactures by releasing the recent family of reflect lenses. From a professional perspective I reviewed the first Tokina mirror lens, SZX SUPER TELE 400mm F8 Reflex MF, and after one year, its successor was released and this new lens excited me more on the character and performance!
Even with more elements in its sophisticated optical design with 7 elements in 7 groups and longer focal length and bigger pupil, Tokina SZ 500mm surprisingly weight "less" than its predecessor! This fact is a great achievement on engineering side which brings a peak design for this lens both optically and on portability viewpoint. Everything is ready for an adventure in far distances through the nature or atop mountains with a super tele in bag.
Tokina SZ 500mm f8 small size rely on its Catadioptric optical system which involves both the reflecting and refracting elements. In this respect, optical designers could achieve a nearly aberration free both on spherical and chromatic aberrations. However the presence of central obstruction disk (Secondry mirror) in Catadioptric systems cause a lower contrast respect to conventional refracting lenses. Also a different type of bokeh is produced by these systems. This bokeh has the shape of donut for point sources but in extended objects the story is different. I performed a photography session in tulips garden and bokeh characteristic of this lens both in foreground and background could be explore through the following images.
The above pictures also show the ability of macrography with Tokina SZ 500mm lens. I love the huge working distance of a super-tele acting as a macro lens which is vital to capture images of insects or subjects not reachable by foot! Moreover, the image rendered by a telephoto lens is flat, so Tokina SZ 500mm lens is a "portrait macro" lens!
Tokina SZ 500mm is a full frame lens, so the distribution of performance parameters across the frame are main questions. In this respect vignette, sharpness and lateral chromatic aberration are three mains should be considered carefully across the field from center to corners. The later, i.e. lateral chromatic aberration, is very low and negligible due to reflecting type of the lens so not an issue. Respect to sharpness distribution of Tokina SZ 500mm, the lens shows an even distribution across the frame as below.
Apart sharpness distribution, what about the sharpness itself? Sharpness or acutance, refers to how crisp an image appears and the ability of resolving fine details and usually measures quantitatively in laboratories. However in practice, the final sharpness of a photo does not depend only on lens; instead it depends on many more parameters like vibrations, ISO sensitivity, distance of the subject, and atmospheric transparency, and of course focusing accuracy. I wrote a complete part on review of Tokina SZX 400mm lens on different parameters which affect lens sharpness in practice which you could find in this article.
Vignette is another performance parameter is defined as reduction of brightness from center to periphery of the image. Tokina SZ 500mm lens produce strong bokeh on full frame sensors. For photographers, the presence of bokeh has two sides on rendering image characteristics. In one side, it could be incorporated as a visual effect to emphasize on the importance of subject usually in portraits and dramatic works.
On the other side, strong bokeh on a constant aperture lens like Tokina SZ 500mm could be a challenge to be controlled for specific works like panorama techniques. I am a real big fan of making super resolution images using panorama technique in which the desired field of view break down to several overlapped sub-exposures. In term of settings, all sub- exposures should be identically taken and the even brightness distribution on each sub-exposures is critical on photo merge stage. Creating the uniform brightness distribution across the field (i.e. vanishing vignette) is usually apply by closing the diaphragm but for a lens with constant f-number all should be done in post processing step. Fortunately at this era of digital image processing, any type of vignette on image could be removed using extensive post processed techniques and tools.
For a panorama landscape, Tokina SZ 500mm frame in vertical position is swept left to right. Middle: without vignette correction, the uneven distribution of brightness results to imperfections in photo merge. The uneven light distribution in raw images is corrected by radial filter in PS, then the final results is much pleasing!
And my last observation on optical performance of Tokina SZ 500mm related to ghost and flare. In this respect on a challenging condition, I set up lens and camera to photograph a video time-lapse of moonrise behind Milad tower. As the moon got height above horizon its brightness increase and finally it turns to an overexposed shiny ball in pitch dark sky background! Such conditions is really challenged the resistance of optics for any ghost and flare. Tokina SZ 500m lens multi coating surfaces resist well for ghosts, but there is a unique lens flare for occasions that strong light source moved to corners and even out of the frame. Lens flare suffer the image by lowering the contrast and it is usually an unprocessable phenomena, so should be considered carefully.
All in all, as I share you my feedbacks using this lens through a year, I could simply express my feeling on how much I like this buddy! Tokina SZ 500mm reflect lens with a compact size and light weight brings me the unique opportunity to carry a super-tele in my bag anytime and anywhere, and open me a new door in my photography journey.