Pentax SMC A 50mm f/2.8 Macro 1:2

Impressions:

• The lens is sharp in wide open aperture
• Focusing ring is ideal for manual focus. It is the best kept secrets for old Pentax lens in A, K, M Pentax lens that they provide the best manual focusing in close up.
  
• I find the lens harder to use due to short focusing distance
  
• I prefer my other close up lens with K 100mm f/4.0 with longer minimum focusing distance
  
• Lens is perhaps more suited to flowers than bugs
• I tried close up on my boys and the lens come up very sharp for portraits
• Color and contrast is outstanding but a touch less than K 100mm f/4.0
  

Related:

• Tamron 70-300 Di LD Macro
• Pentax K 100mm f/4.0 Macro 1:2
• Vivitar AT-22 Extension Tubes
• 1:1 Macro with Extension Tubes
• Cosina 1:1 matched macro adapter
• Kenko 2x Macro Teleplus MC7
• Hin's Camera Gear