Why don't you shoot M42 with a 500mm mirror lens?? This is why.: Astrophotography Talk Forum Forum: Digital Photography Review
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Samyang MF 500mm F8.0 Mirror Lens M42 Mount - DSLR, CSC Telephoto Lens, Manual Focus, Filter Diameter 72mm, for Full Frame and APS-C: Buy Online at Best Price in UAE - Amazon.ae
![Used Pentax 500mm f/4.5 Takumar M42 Lens w/ Case and Caps - For Parts or Repair - Green Mountain Camera Used Pentax 500mm f/4.5 Takumar M42 Lens w/ Case and Caps - For Parts or Repair - Green Mountain Camera](https://www.gmcamera.com/wp-content/uploads/2022/11/Q2FZCJ09PC-IMG_0086-247x296.jpg)
Used Pentax 500mm f/4.5 Takumar M42 Lens w/ Case and Caps - For Parts or Repair - Green Mountain Camera
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