DIY(HELICOID)---CONTAX G45

DIY(HELICOID)---CONTAX G45 TO M MOUNT CONVERSION

If you hava a Contax G45 lens and want to use it on Leica cameras, all you need is a converted helicoid. You can use our helicoid to replace the original Contax G45 helicoid by yourself.

Step One: Disassemble Contax G45

• Preparations before disassembly

(1) Tools list: a screwdriver (Φ1.0-2.6), a tweezer, paperclips, rubber;

(2) Working environment: try to operate under sufficient light and dust-free environment;

(3) Note: In order to protect the lens, it is recommended to use finger cots or gloves throughout the operation.

• Remove the lens ring from the original Contax G45 lens

(1) Turn the aperture from 5.6 to the position as shown in the picture below;

(2) Press the rubber against the lens, rotate the rubber counterclockwise and remove the front ring;

(3) Use the screwdriver to remove the 4 screws (do not scratch the lens) and take out the second ring.

• Take out the optical lens group and its gaskets

(1) Tilt the lens downward and take out the optical lens group and its gaskets;

(2) Note: After taking out the lens group, please put the lens group upside down on the table to prevent the rear lens (convex side) from being scratched.

Step Two: Replace the Helicoid

• Assembly list

❶ Optical lens group; ❷ Helicoid; ❸ Gaskets; ❹ Lens rings; ❺ Tools

• Adjust the aperture and place gaskets

(1) Remove the four screws of the helicoid and take out the ring;

(2) Adjust the aperture to 5.6 to make the gaps of the two parts in the helicoid coincide;

(3) Locate the 2 screw ports adjacent to the aperture lever of the optical lens group, and adjust the lever to the middle of them;

(4) Place gaskets and use a paperclip to align the hole of gaskets with the screw hole of the optical lens group (for the number of gaskets, please refer to the description of M-mount cameras infinite focus proofreading at the end).

• Put the optical lens group into M-mount helicoid

(1) With the help of a paperclip, align the screw holes of the lens group, gaskets and the helicoid;

(2) Align the aperture lever of the lens group with the groove of the helicoid, and place it vertically.

• Check and complete the replacement

(1) After placing it horizontally, make sure the 4 screw holes of the lens group, the ring and the helicoid are aligned, rotate the aperture ring and the aperture will change accordingly, indicating that the installation is in place. Please do not pull out the paperclip during checking;

(2) Install the 4 screws and the front ring and complete the replacement.

• M-mount cameras infinite focus proofreading

(1) Take the vertical reference object from 30 meters away and if the image is clear at ∞, please do not add the gasket;

(2) If the image is not clear at ∞, please reduce the gasket;

(3) If the image is clear at 5-∞, please add the gasket.

Contax G45 to Leica M Mount Conversion Kit Specifications

Specification：

Mount: M
Focal Length: 45mm
Format: Full frame
Minimum Focus Distance: 0.7 m (2.30 ft)
Maximum Aperture: F2.0
Minimum Aperture: F16
Filter Diameter: 46mm
Body Material: Brass, chrome plated
Weight: 332 g (11.7 oz)
Dimensions: 56 × 46 mm (2.20 x 1.81 in)
Lens Cap: CNC metal

In the Box-content：

1 x Funleader G45 Converted Lens / Helicoid
2 x Gaskets (Only for Helicoid)
1 x Rubber (Only for Helicoid)