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ROLLEI SONNAR 40MM F2.8 HFT
HAND-CONVERTED RANGEFINDER LENS FOR LEICA L39 / M MOUNT

I know many of you have been waiting for this moment.
From my first post to now, two years has passed.
After five rounds of revisions and mechanical upgrades, I can finally present this lens:
The Carl Zeiss Sonnar 40mm F2.8 HFT, originally from the Rollei 35S camera, now fully reborn as a true rangefinder lens.
While preserving its original optical design and imaging character, I carried out a complete rangefinder system conversion, transforming it into a hand-crafted lens genuinely usable on Leica rangefinder cameras.

Key Features & Functions
Entire lens body constructed from solid brass
Supports Leica L39 and Leica M mount
Full rangefinder coupling (Leica RF cam)
Aperture control fully relocated to the lens barrel
Original focusing mechanism retained
Newly added 0.3 m close-focus capability (mirrorless & Live View use)
Minimum focusing distance with rangefinder coupling: 0.9 m
Custom solid brass cylindrical lens hood included
Smooth, precise focusing feel with refined throw and damping

This lens is not for those chasing extreme specifications.
But it is perfectly suited for:
Photographers who enjoy the rhythm of rangefinder shooting
Photographers who love the language of film photography
Creators who use both Leica M and mirrorless systems
Those seeking a lens with history, character, and real creative usability

Conclusion
This hand-converted Rollei Sonnar 40mm F2.8
retains the soul of the original Sonnar design.
It is made for photographers who truly enjoy the act of photographing—
those who appreciate the pace of rangefinder cameras,
understand the visual language of film,
and move freely between Leica M and modern mirrorless systems.

It is a lens that inherits history while carrying forward a future.

Mandler 35mm F2 Winter Shooting Experience (2025) Review

First, my fingers were very cold;

Second, the Leica camera's metal was also cold;

Third, wearing a hat, a thick coat, and warm pants is very important.

Okay! Jokes over, let's officially talk about the shooting experience with the Mandler 35mm F2 lens.

If you want to buy this lens, please PM. Thanks!

Shooting parameters:
Camera used: Leica M9
Lens aperture: F2
Camera ISO: 200
Shutter speed: Auto.

Because the aperture was fixed at F2, the depth of field was very shallow. Combined with the winter wind and constantly swaying branches, achieving precise focus was indeed difficult and challenging, but fortunately, I managed it.

Color Representation: Reference image – Warning Can

The Mandler 35mm F2's color reproduction has a unique "richness." It can present vibrant colors like green, orange, red, and yellow in a saturated, textured, yet not greasy way. The image possesses the richness and depth of a classic vintage lens painting, while maintaining the clarity and three-dimensionality of modern optics. This balance of "retro + contemporary" makes it particularly captivating in natural light: the greens are more subdued, the warm colors brighter, and the layers feel more breathable.

Background blur effect: Reference image - Snow Rose

The Mandler 35mm F2 creates a subtle sense of rotation when blurring the background, a characteristic of many vintage lenses, particularly evident in the Helios 44-2. This 35mm lens, however, is more restrained: its bokeh is softly lemon-shaped, gently encircling the subject without overshadowing it. The image still steadily guides the viewer's eye to the subject. I prefer to call this effect "soft dramatic bokeh"—it's not the most exaggerated or eye-catching blur, but its smooth transitions and soft layers create a dramatic yet natural effect. This perfectly balanced background atmosphere is one of its most captivating qualities.

Center Sharpness at F2: Reference Image – Pine Tree Branches

The Mandler 35mm F2 is undoubtedly a "new classic"—new optical glass, new coating technology, and new manufacturing process allow it to exhibit extremely high center sharpness and contrast even at its widest aperture of F2. Areas in the image that are not on the same depth-of-field plane are quickly softened, resulting in a clean and clear bokeh effect, but without the abruptness of "extremely sharp in the center, immediately collapsing at the edges." Instead, the entire transition from sharpness to bokeh maintains the smooth, soft, and natural tone characteristic of the Mandler series. Even at its widest aperture, it still presents a smooth sense of three-dimensionality and a harmonious atmosphere, which is its truly captivating quality.

Glare Shooting: Reference Image – Backlit Ice Rose

Usually, when glare occurs in shooting, the image will have a thin layer of mist, presenting a soft atmosphere. However, the Mandler 35mm F2's control is outstanding. Even in backlit or brightly lit environments where a slight haziness occurs, the sharpness and contrast at the center of the image remain at a high level. Compared to many older lenses that often suffer from "white fog" and loss of detail, the Mandler 35mm F2's flare handling is more restrained and stable, achieving a good balance between atmosphere and usability.

Maximum Aperture Edge Sharpness: Reference Image---Poster Column

To verify the Mandler 35mm F2's edge sharpness at its maximum aperture, I specifically took a photo of a poster column. From this image, we can clearly observe the lens's image circle performance and vignetting.

First, vignetting does exist, but it's minimal. The slight vignetting adds a touch of atmosphere without disrupting the overall look; instead, it makes the subject more focused.

The center sharpness and contrast are very high, with clear detail. The resolution gradually softens towards the corners. The outline of the paper and the text are still discernible, but the edges are no longer so sharp, instead possessing a slight blurring effect. This combination of strong clarity in the central area and gentle treatment around the edges enhances the prominence of the subject and the three-dimensionality of the image.

I am not a professional photography equipment reviewer. As a photographer, I have tried to introduce this Mandler 35mm F2 lens in my own way, as comprehensively as possible and without my own subjective opinions. If I have omitted anything, please let me know. Thank you.

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Mandler 35mm F2 Brass and Aluminum Versions Comparison

The silver version is the Brass Mandler 35mm F2 lens;
The black version is the Aluminum Mandler 35mm F2 lens.

Differences between the two lenses:
Accessories:
Silver (Brass version):
1. It comes with a lens box and accessory box.

2. The entire lens is made of Brass.

3. The lens cap, round lens hood, square lens hood, and UV filter are all made of Brass.

Black (Aluminum version):
1. It only comes with a lens box (including accessories).

2. The outer ring of the lens is aluminum alloy, and the inner ring is copper.

3. The square lens hood is made of aluminum alloy.

4. The lens cap, round lens hood, and UV filter are all made of aluminum alloy.

Weight:
The silver version is the copper Mandler lens: 199g
The black version is the aluminum Mandler lens: 147.5g

User Experience:

Both versions of the lens have the same lens element structure and coating, so the image quality and color are identical. The biggest difference lies in their balance point when mounted on the camera. The aluminum Mandler lens has a balance point towards the rear of the camera, lacking the weighty feel often associated with it; the copper Mandler lens has a balance point towards the front of the camera, making it more comfortable to hold.

Regarding the mechanical structure, although the two versions use different materials, their internal structures are identical. The aluminum version has a gap between the front and rear of the aperture ring at the maximum and minimum apertures; the copper version's components are more tightly integrated, especially the aperture adjustment, which is more noticeable without any looseness or gaps.

Value for money:

As a photographer, I use lenses and cameras for shooting and general purposes. From my personal perspective, I would recommend the aluminum version of the Mandler 35mm F2 lens. It's lightweight, sufficient for most needs, and you won't feel bad about bumping into it. Its price is more commensurate with the actual image quality it delivers.