Disassembly – Risespray 35mm F0.95 lens (Fuji X mount)

There are very few F0.95 lens for APS-C sensor on the market, and Zhongyi Mitakon 35mm F0.95 mark II is the most compact and affordable since 2016. Oh wait, it was! There is one more new lens appeared under name “Risespray” (and few other brand names). Finally I’ve got hands on lens sample and going to disassemble it and see how it compares to Zhongyi Mitakon (because it looks very close to it optically).

Personally, I like to see that more interesting lens options appear produced by Chinese lens factories. And it’s also interesting how quick they are progressing with better quality, design and lens ergonomics. I think Zhongyi did a great job advancing and evolving their Mitakon Speedmaster F0.95 lens series over last 5 years, so it’s not a big surprise that someone decided to reuse that experience and produce a re-branded but also revisited version of 35mm F0.95 lens.

The most informative optical performance review of Risespray 35mm F0.95 is already written by Jonathan Hrovath. So I’ll not focus on that area, but going to explore mechanical internals. It’s interesting co-occurrence though, that I’m going to work with exactly same lens sample which Jonathan reviewed in article : ) With SN: QL00038, Fuji X photographers world is really so connected : ))

Tech specs comparison

Before I start the disassembly let have a quick look at top technical specifications comparison of Mitakon vs Risespray.

Risespray 35mm F0.95Mitakon 35mm F0.95 MkII
Weight365 g460 g
Aperture blades12 (rounded)9
Filter size52 mm55 mm
Optical formula11 elements in 8 groups11 elements in 8 groups

That is very interesting! This lens has similar (or same) optical design as Mitakon, but is 95 g. lighter. I’m very curious to see what Chinese engineers did to accomplish such a significant weight reduction.

Lens disassembly – rear area

Traditionally I’m starting with disassembling the rear lens area. Risespray 35mm F0.95 has three mount ring bolts that need to be unscrewed first.

Then you can elevate mount ring – it’s very thick but made of light weighted metal alloy (comparing to more durable but also heavy brass in Mitakon mount ring).

Nice surprise! Rear glass element is not mounted inside of mount ring (like in Mitakon), but stays connected to lens core. That is significant mechanical design difference.

There is a focus distance calibrating shim made of thin plastic.

Continuing with disassembly and unscrewing four black bolts in the outer ring with “35mm” sign. NOTE: bolts sit quite tight, and in my lens sample few of them have slightly damaged heads, probably it got assembled or re-assembled using not very precise screwdriver.

After removing black case ring, I’m using red marker to memorize position of black frame holding the rear glass element. After that I’m unscrewing another set of four black bolts, and pulling that frame away.

Now I have access to the next optical surface. Let have a look how it moves when the lens is focusing.

As you can see the lens core is moving up/down, while that removed metal frame is designed to keep rear glass element at same place. That is exactly same optical design as in Mitakon, but very different mechanical implementation. You can also see two holes in metal frame sides – they are serving for air circulation during lens core movement, so the air remains inside lens – smart idea!

There is nothing interesting to disassemble at this point, so assembling everything back, and also doing some focus calibration.

Infinity focus calibration

I tested this Risespray 35mm F0.95 lens on Fuji X-E2s camera, and real infinity focus appears right near the center of infinity mark, then focus can be rotated further “overpassing” infinity. So I’m making calibrating shims from aluminum plate. Unlike with Mitakon where you can calibrate focus position using external focus ring bolts, with Risespray adding focus calibration shims under mount ring is the only option.

It’s easier to make just three sections, instead of more complex shape of circle with openings for bolts. So I’m cutting ring, then circle, then three sections.

Putting calibrating shims on top of factory provided shim ring, to fit screws places remain open.

Assembled and tested lens infinity focus, now it’s much closer to real infinity (and lens can focus closer now), but will need to make one more set of shims later for precise infinity focus.

Lens disassembly – front area

I’m adding rubberized focus ring to this lens, to make the ring a bit wider and nicer to grip (so I can easy know it’s not an aperture ring simply by touching while looking through Fuji X camera eyefinder).

Then I’m using blue Loctite to form a circle and attach it to M42 extension tubes.

This is going to serve as a custom wrench to unscrew the front naming plate. IMPORTANT: keep the lens front pointing up during this procedure, because I think the front glass is not secured under it.

Accurately center rings position then gently press down so Loctite is sticked to nameplate ring. Then accurately unscrew it CCW. Yes, it looks like nothing is holding the front glass element from falling out, so keep lens facing up all the time. I’m only tilting it to the side for better visibility on pictures.

Unscrew four black bolts around the glass element, and remove front case ring.

There is some grease and thin plastic shim, remove that ring.

Then remove the aperture ring. NOTE: there is a socket for aperture transmission brass bolt.

Then unscrew another set of four black bolts holding the focus ring, and remove it.

That is very interesting – focusing is implemented very differently in this lens. Mitakon is using classical helicoid with sliding rails. Risespray 35mm F0.95 lens has more complex to make curved threads, which is very nice solution. That explains why Risespray has so precise manual focusing without any directional-switch play (I had that focus play in all four Mitakon 35mm F0.95 MkII samples worked with before). Nice job done by lens manufacturer.

Looks like inner focusing ring is locked on place by radial spring. I don’t plan to disassemble it further. In case you need to lubricate focusing cylinders, this radial spring need to be removed, and also two focusing thread bolts need to be unscrewed.

One more look at focusing mechanism at different focused distances.

I’m assembling the lens back, which is quite straight forward process without any difficulties. Just make sure you set correct radial orientation of every ring, so makings on them fit the line between “35mm” and “1:0.95” signs.

Conclusions

Engineers that manufactured this 35mm F0.95 did a great gob completely redesigning all mechanics comparing to Mitakon 35mm F0.95 Speedmaster lens. I think they made much better implementation with lots of benefits. All frame is made of metal and has durable parts, it’s also precisely machined and cylinders sit very tight without excessive play, and have smooth rotations.

Personally, I like this lens mechanics more than Mitakon’s one, just because focusing is more smooth and without any directional play. Aperture ring is also nicely machined and does not have play. Including 12-blade aperture with much better curved shape at closed stops is another great change.

Risespray 35mm F0.95 lens weight is leading to better balance on smaller Fuji X bodies like X-T30 and X-E2s. With Mitakon I used to attach thumb rest to camera hotshoe. But with lighter version of 35mm F0.95 I don’t feel the need to do it.

My next journey with Risespray 35mm F0.95 lens will be discovering a way to introduce click-stop aperture. It will be slightly different then with Mitakon 35mm F0.95 MkII aperture mod, due to another way optics frame is constructed, so I need time to design it in a simple way.

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