F* 300 f4.5 or DA * 300 f4?

Anybody able to offer a direct comparison of above?
Am aware of the differeces in weight and weathersealing, but how do the different focus mechanisms compare?


Davex.

No weather sealing on F* and screw focus compared to SDM (actually faster imo) IQ wise there is very little, if anything in it.

F* 880g LINK gets 100%

DA* 1160g with hood LINK (F* has built in hood) and gets 9.75%

The DA is slightly sharper wide open. Not much in it stopped down.
It's also faster and quieter focusing. Works well with the 1.7AF

The DA* 300mm I tried wasn't faster focusing, if anything the SDM (as usual) was slower. Certainly quieter though.

Both work well with the 1.7x af.

TBH do not like the 1.7x af
Tried one for a few months, never realy got on with it,I am aware of it`s perceived desirability in Pentax world, but as i say not for me.

I have a 1.5x (cannot remember all the letters) that works well with SDM and screwdrive, it even works with my 18-135 WR.
Will pair that with the 300mm when I decide what to go for, atm I do not need weatherproofing so the F* is favourite, however will know next week if I am going to spend some time in a tropical rainforrest, if so then the DA* will probably be required.

Davex.

Personally I'd go for the F* but only because I could use it on my film cameras as well. The DA* doesn't, AFAIK, have an aperture ring.

K.

DA* 300/4 - 1.4m - 77mm - D=83mm - L=184 mm - 1070g - weather sealing - no aperture ring - SDM - separate hood - tripod mount - 1:4

FA* 300/4.5 - 2m - 67mm - D=73mm - L=160mm - 935g - no weather sealing - aperture ring - screw AF - separate hood - no tripod mount - 1:6

F* 300/4.5 - 2m - 67mm - D=84mm - L=160mm - 880g - no weather sealing - aperture ring - screw AF - integrated hood - (removable) tripod mount - 1:6

http://kmp.bdimitrov.de/lenses/primes/extreme-tele/DA300f4.html
http://kmp.bdimitrov.de/lenses/primes/extreme-tele/FA300f4.5.html
http://kmp.bdimitrov.de/lenses/primes/extreme-tele/F300f4.5.html

FA* on K10D: http://www.photozone.de/pentax/131-pentax-smc-fa-300mm-f45-ed-if-review--lab-tes...
DA* on K-5: http://www.photozone.de/pentax/643-pentax300f4

I own the FA*.

I tried the FA* and the DA* side by side. The FA* was fractionally faster focusing (no doubt here) however the DA* is fractionally sharper. What swung it for me though was not the WR but the near silent focusing, the FA* is rather noisy and probably not the best for birds within close proximity that could be disturbed by the sound.

I know that's not the F* but near enough.