Type SK / Zero Optik Canon “Dream Set” / TLS Canon Rangefinder
Explaining the Similarities and Differences of these 3 Lens Sets
The short explanation: all 3 of these lens sets are rehoused Canon Rangefinder still photo lenses from the 1960s. These lenses were used with Canon and Leica rangefinder cameras of that era, and typically had LTM mounts (Leica Thread Mount), which is why they are often referred to as Canon LTM lenses.
Canon rangefinder lenses have excellent optical performance despite their age. Since rangefinder cameras have no mirror reflex system like SLR cameras, the lenses sit very close to the film plane. This allowed optical designs that kept the lenses fairly small despite their speed. They also have excellent center sharpness and surprisingly good aberration control.
All three of these sets have basically the same 1960s Canon optics, but they are named and marketed differently. In fact, in all 3 sets, the 35, 40, 85, 100, and 135 are the exact same donor lenses. The 50mm lenses are not the same in each set, and the 25mm/28mm lenses are different in each set. Since the optics are either identical, or very similar (depending on the focal length), all three sets will deliver very similar images in regards to character.
They all have 110mm fronts, are similar in size and weight, and all have excellent close focus. There are some specific optical difference, but most of the differences are in the housings, specifically the mounts. As an example, in the photos here, you can see the 35mm from each set. They all have the same Canon 35mm f1.5 donor lens (the Type SK on the left simply removed Canon’s original engraved front ring).
As for the differences: with the Type SKs, they use some of Canon’s original irises, which are typically a 10-blade petal shaped design. TLS and Zero Optik replace all the irises with new circular irises. So wide open, all 3 sets deliver the same results. Stopped down, bokeh will have a flower petal shape to it in some of the Type SKs (25, 35mm, 50mm). In the TLS and Zero Optik sets, bokeh stays circular with every lens at all T stops.
The 50s
A big optical and therefore character difference between the Type SKs and the TLS/Zero Optik sets, are ethe 50mm primes. The Type SK 50mm is based on the Canon 50mm f1.4. It’s an excellent lens, with very good wide-open performance. The 50mm f1.4 is your typical “fast 50,” and like most fast 50s it’s very good.
The TLS and Zero Optik sets use the more exotic Canon 50mm f0.95 “Dream Lens.” This lens received its nickname because of the dreamy character it delivers when shot wide open. Stop down, and the lens delivers sharper and less extreme results. The “Dream Lens” flares much bigger and more beautifully than the Type SK 50mm. Worth noting, the “Dream Lens” is actually a better match to the 35mm in regard to bokeh and fall off.
THE 25s and THE 28s
The other big optical differences are with the 25mm and/or 28mm lenses in each set. The Zero Optik 28mm uses a vintage 28mm f2.8. It was chosen because its color, contrast, sharpness, bokeh and flares, are a very good match to the rest of the set. The original Canon Rangefinder 25mm and 28mm are also slow lenses AND they don’t have anywhere near as beautiful character as the Canon 35mm, 50mm, 85mm, 100mm, or the Zero Optik 28mm. We feel the Zero Optik 28mm is a great match. The down side, it’s very slow at T3.6.
The Type SK 25mm and 28mm and TLS 25mm and 28mm have advantages over the Zero Optik 28mm. Both the Type SK and TLS 25mm and 28mm are based on faster Canon primes, with additional optics added to achieve a wider field of view. The advantage is that they are fast and since they are based on Canon primes from the same era, they share the character of those lenses. The lenses have more dramatic fall off out to the edges.
The SK and TLS 25mm and 28mm lenses are very similar in performance and character, but there are subtle differences. The Type SKs uses more modern optics, with modern multi-coated glass. The TLS 25mm and 28mm are OFG’s own optical recipes, and uses 100% vintage optics with single-layer coatings, and therefore flare character is a better match to the rest of the set with the TLS 25mm. The TLS 25mm also has slightly better sensor coverage. The TLS 25mm is sharper than the Type SK, and has less fall off. Other than that, they are very similar.
THE 20s
Like the 25mm and 28m, the Type SK 20mm is based on a Canon prime with additional modern optics to create the new focal length. Like the 25mm and 28mm, it has heavy falloff. The TLS 19mm is based on the Canon FL 19mm f3.5. It’s slower but has better edge performance and better sensor coverage than the Type SK 20mm.
THE MOUNTS
Each of these sets use a different mount. The Type SKs are PL mount. This great because it’s the most common, industry standard mount. The only negative to this: on the 25mm and 35mm, you will see some vignette on ARRI LF Open Gate 4.5K. At a 16x9 crop, it’s only really visible when focus is set to infinity.
The TLS set is LPL. LPL is quickly becoming an industry standard. Like PL it’s a proper, sturdy, reliable, professional mount. Due to the wider diameter of LPL, and shallower flange distance, the TLS 25mm, and 35mm have better sensor coverage than the Type SKs while still having excellent close focus.
The Zero Optik Set uses Leica M Mount. Although it’s originally a still photography mount, it’s quite robust, and all our Leica M camera mounts use a positive locking system which results in no wiggle or play, and maintains proper flange distance assuring the lenses can hit infinity focus, and that focus marks are accurate. Like LPL, Leica M allows maximum sensor coverage on the wider lenses, while still having excellent close focus. Zero Optik has started building these sets in LPL mount as well.
IN SUMMARY…
Type SK Primes
1960s Canon Rangefinder optics
PL Mount
110mm Fronts
Mix of some original irises, and some new irises
50mm is a Canon 50mm f1.4
20mm, 25mm, 28mm are new lens designs based on the Canon primes & additional modern optics
TLS Canon Rangefinder Primes
1960s Canon Rangefinder optics
LPL Mount
110mm Fronts
New circular irises
50mm is the Canon “Dream Lens” 50mm f0.95
25mm, 28mm are new lens designs based on the Canon primes & additional vintage optics
Zero Optik Canon Rangefinder Primes (Canon “Dream Set”)
1960s Canon Rangefinder optics
Leica M Mount / LPL Mount
110mm Fronts
50mm is the Canon “Dream Lens” 50mm f0.95
New circular irises
28mm is a slower 28mm f2.8
RECOMMENDATIONS
We think the TLS set is the best all-around option. LPL is a great mount. The housings are excellent. We prefer the incredible look of the Canon 50mm f0.95, and our custom 25mm and 28mm. We also like that every lens has new circular irises, which give the set more consistency regardless of which lens you are using and at what T stop.
The Type SKs are a great option if you want the convenience of PL mount. Their housings are not quite at the level of TLS or Zero Optik, but they get the job done for sure.
The Zero Optik set is slightly lighter, and focuses slightly closer than the other two sets, and of course has Zero Optik’s amazing build quality. They also happen to be the lenses used to shoot Zack Snyder’s ‘Army of the Dead.’
You can’t go wrong with any of them, and in many ways they are interchangeable. Also, if you have a multi-camera shoot where you need a lot of extra lenses, they can be mixed, and they match so well.
ZERO OPTIK MAMIYA 48mm T1.7
If you want to go “off menu” please ask us about our Zero Optik rehoused Mamiya 48mm T1.7 (f1.5). We got this lens rehoused as an alternative to the Canon Dream Lens 50mm T1.1 (f0.95) in our TLS Rangefinder set, and as an alternative to to 50mm T1.6 in the Type SK set. In regards to character and performance it sits right in between those two lenses: it’s not as wild as the 50mm f0.95 “Dream Lens” but it has more character than the Type SK 50mm.
So if you want a lens that fits will into either of these sets, and has similar character, the Mamiya 48mm is a great alternative. It has the same gold, single layer coatings, delivering big lens flares. It has amazing textured bokeh. It’s sharp on center with a pleasing amount of fall off, and almost no chromatic aberration. You have to look far and wide to find a lens that delivers nearly as much character as the Dream Lens, but at the more practical f stop, and we feel like we found it with the Mamaiya 48mm.
Zero Optik Mamiya 48mm T1.7