===== Pentax-A 645 SMC 45mm f/2.8 ===== 
{{ :lens:pentax-a645smc45mmf2.8.png?300|}}
==== Summary ====
The SMC Pentax-A 645 45mm f/2.8 is a compact, manual-focus wide-angle prime introduced in 1984 for the Pentax 645 medium format system. With a field of view equivalent to ~28–30mm on 35mm film, it’s designed for landscape, street, and environmental portraiture, offering a fast aperture and lightweight build for handheld shooting. Optically, it features a 9-element/8-group design with Super Multi-Coating (SMC), an 8-blade automatic diaphragm, and a minimum aperture of f/22. It focuses down to 45cm, delivers 0.15× magnification, and uses a 67mm filter thread. The lens weighs 400g, measures 74 × 66.5mm, and includes a dedicated screw-in hood (RH-RA 70mm) and soft case (S80-120). It has an “A” setting on the aperture ring, enabling full automation on modern Pentax 645 bodies.
==== Tech Specs ====
| Manufacturer    |Pentax|
| Series          |Pentax-A|
| Model           |645 SMC|
| Focal Length    |45mm|
| Max Aperture    |f/2.8|
| Min Aperture    |f/22|
| Format          |645 film|
| Image Circle    |-|
| Minimum Focus   |45cm|
| Focus Rotation  |°|
| Iris Blades     |8|
| Optical Design  |9/8|
| Squeeze         |none|
| Front Diameter  |74mm|
| Filter Thread   |67mm|
| Focus/Zoom Rod  |none|
| Native Mount    |Pentax 645|
| Data Protocol   |none|
| Length          |66.5mm|
| Weight          |400g|
| Body Telescope  |-|
| Body Material   |-|
| Focus Drive     |-|
| Iris Drive      |-|
| Zoom Drive      |-|
==== History ====
Country of Origin:  \\
Release Date:  \\
Launch Price:  \\
Design Revisions:  \\

==== Service ====
<nodisp 8>
Service Manual: (Insert link to manual here) \\
\\
Full CLA: **TBD hrs.**\\
<wrap note></wrap>\\
</nodisp>
==== Cine-Mod ====
<nodisp 8>
Focus Ring O.D.: -\\
Zoom Ring O.D.: -\\
Iris Ring O.D.: -\\
De-click Y/N: -\\
Additional Notes: \\
</nodisp>
==== Notes ====
==== Media ====