Alles wat aar zoal meemaakt

400-500mm shootout

At the long-lens front these are compared:

  • Pentax-M 300mm * + 1.4x converter-S
  • Sigma 50-500 @ 500mm
  • Tamron SP500 mirror lens

Comparisons are done at F/8.0 This is the fixed aperture of the mirror lens. The M300 is set at F/5.6; the 1.4x extender adds a stop to make it F/8.0.

M300 x 1.4 F/8
50-500 500 F/8
SP500 F/8

Extra: the M300 x 1.4 and Bigma at F/13:

M300 x 1.4 F/13
50-500 500 F/13


  • Best is the Bigma, then M300 x 1.4 extender and SP500 comes in last
  • At F/13 the Bigma is much better than M300 + extender
  • As seen before, the Bigma is actually shorter than 500, even less than 300 x 1.4!