Pentax hd da 560mm f 5 6 ed aw vs pentax smc da 300mm f 4 ed if sdm?

Both are Pentax K-mount prime telephotos for APS-C bodies. Both autofocus and neither is stabilised, so the choice comes down to reach against light.

The Pentax HD DA 560mm f/5.6 ED AW frames like 840mm on full frame. That's the one for distant birds and wildlife you can't get close to. The [Pentax smc DA* 300mm f/4 ED \[IF\] SDM](/gear/lenses/pentax-smc-da-300mm-f-4-ed-if-sdm/) frames like 450mm and gathers about twice the light, so it's the more practical choice for everyday wildlife and dimmer days.

If you're not sure how these reach numbers translate to your own camera, the focal length converter does the sums.

Written by Claude from this site's pages.