Click-stop aperture for 7artisans 35mm F1.2 lens

7artisans 35mm F1.2 lens has click-less smooth rotating aperture ring by design. Its texture is very different from focus ring so it’s easy to identify by just touching rings while keep looking into viewfinder. However when you want to check the aperture value during shooting you have to look at the top of the lens to read it, and make sure desired value is set. Alternatively I’m simply rotating aperture ring to the very end to set F1.2.

Today I’ve finally modded this lens to the aperture click-stop version.

Advertisements

7artisans 55mm F1.4 review (Fuji FX mount)

It’s a joy to use true manual focus lens on Fuji X cameras thankfully to quite convenient focus assist system. It’s the main reason for me to use third party lens available for Fuji X mount, or adapting another compact lens options. One of my favorite adapted lens on Fuji X camera is Voigtlander 50mm F1.5. Though it’s designed for a Full Frame and is a bit heavy. But I like it for small size and decent moderate sharpness so great for portrait. Of course any other lens APS-C alternative should be optically smaller so I was always looking for another options. 7artisans 55mm F1.4 is quite interesting candidate due to attractive price and 14-blades aperture.

7artisans 55mm F1.4 – calibrate infinity focus

My 7artisans 55mm F1.4 lens sample for Fuji X mount had the focusing problem. I was not able to focus further than about 50ft. Everything furhter was blurred in spite lens focus mark was at infinity mark.

Typically it means that focus position is a bit shifted toward the target. Optics need to be positioned a bit closer to the camera. Fortunately 7artisans engineers provide simple built in classic solution – calibration shims.

eXperiment – 7artisans 12mm F2.8 – extra opened aperture

Typically lens are designed to have perfect round aperture opening circle at maximum value. It looks unusual that 7artisans 12mm F2.8 lens works differently.

7artisans 12mm F2.8 lens aperture mechanism is purposely limiting 7 aperture blades to open completely at F2.8. It’s observed on all lens samples I had chance to see or explored online. So its not a single sample flaw but technical decision, and your lens sample is a good one if you have the same : )

7artisans 12mm F2.8 – aperture blades at F2.8 value are not opened to the hole borders. That is correct behaviour! : )

I’m disassembling the lens again to experiment with its aperture. I’m going to set blades opened completely and see how it is affcting the image.

7artisans 12mm F2.8 lens – partial disassembly

Finally I found some time to discover more details about 7artisans 12mm F2.8. I’ve been sparingly shooting with it and posted some samples from Fuji X-E2s on related Flickr public group .

I’ve recently reviewed 7artisans 12mm F2.8 on 35MMC , and during that review noticed that aperture blades are not completely opened at F2.8. Another reason for the disassembly was quite large dust particle under the rear glass in my sample.

7artisans 12mm F2.8 lens. The custom drop of red paint just helps to read F value faster.

Carl Zeiss 50mm F2 T* ZM Planar – lens disassembly

Most of Zeiss ZM lens are quite compact and solidly built and work flawlesly for long period of time. The 50mm F2 Planar may only need disassembly for cleaning dust or relubrication. However sometimes you may also want to calibrate the infinity focus point on Leica M body.

Fortunately disassembling ZM 50mm F2 Planar is quite simple process, though it requires precision and some precaution steps.

7artisans 35mm F1.2 – shifting 6th element

After reading great review of 7artisans 35mm F1.2 on 35MMC I explored more details about Sonnar design C Sonnar T* optical formula. I was wondering what happens to the picture if the 6th lens element is placed in same group with 4th and 5th, like it’s done in Zeiss Sonnar C 50mm F1.5 ZM T*.

It’s quite easy to try, because 7artians engineers made the rear lens block very easy to disassemble without using any tools. Regular rubber glove provides firm grip and enough torque to unscrew the metal ring around the 6th element. Then it’s easy to pull out the 6th glass, remove the metal shim under it and place it back, and screw the metal ring to it’s place.

Voigtlander 40mm F1.4 – disassembly

The Voigtlander 40mm F1.4 is one of my favorite CV lens. It renders great on Leica M, and also adapted on Fujinon cameras producing pleasant classic looking images without extra modern sharpness. I had few samples in the past required cleaning of the glass surface in the aperture chamber, and typically disassembled the rear area. In this post I’ll also show how to run disassembly from the front which looks easier.

Comparison – Mitakon 35mm F0.95 MK-II vs 7artisans 35mm F1.2 vs Voigtlander 40mm F1.4 S.C

Today I’ve put Fujinon X-E2s camera on a tripod, set ISO200 and made sequence of shots at different apertures up to F4 with following 3 lens:

• Mitakon Zhongyi 35mm F0.95 MK-II
• 7artisans 35mm F1.2
• Voigtlander 40mm F1.4 S.C

Shots with Voigtlander are made from longer distance to catch same frame area. Then I’ve cut 3264×3264 from each shot (original frame is 4896×3264) to compare square area between each lens.

7artisans 35mm F1.2 (FX mount) – fix mount stuck issue

My 7artisans 35mm F1.2 sample had this problem – camera lock pin catches one of lens mount bolt frame preventing unmount rotation to complete (unless you keep lens lock button pressed all time).