Pentax AF 300mm(ish) Fully Compared

There are not much choices in Pentaxland for telephoto to super-telephoto lenses. In fact, the starting focal for that is at least 300mm IMO, even if we are to use the lenses on the Pentax DSLRs all of which are with a crop factor of 1.5X. To choose a fixed prime for 300mm that supports AF, Pentaxians have only 3 choices over years up till now, since Pentax launched their "new" AFSLR system in 1987, i.e., the F*300/4.5, FA*300/4 and the DA*300/4 SDM. I do note that many Pentaxians do have many confusions for the actual differences between them. So, I write this article to clear them up. And, I share my own personal opinions according to my practical experiences with the lenses, in addition:-

Specifics	F*300/4.5	FA*300/4.5	DA*300/4 SDM
Lens Design:	9 elements in 7 groups, ED and IF (Extra-low Dispersion / Inner(Internal) Focusing)	9 elements in 7 groups, ED and IF, generally believed to be optically identical to the F*	8 elements in 6 groups, ED and IF
(Officially) Guaranteed Image Circle Size:	135 Full Frame	135 Full Frame	APS-C
First Marketed:	1987	1991	2008
Discontinued:	1991	2004	Not Yet
Size:	160 x 84mm (Dia.)	160 x 73mm (Dia.)	184 x 83 mm (Dia.)
Filter Thread:	67mm	67mm	77mm
Weight:	880g	935g	1070g
Tripod Collar:	Yes: Detachable, Rotatable	Nil: No Support / Not Available!	Yes: Built-in, Rotatable
Lens Hood:	Built-in: Screw-in/out Type, Handy, Slim and Lightweight	External: Bayonet, Metal, Bulky, Thick, Large and Heavy	External: Bayonet, Plastic, Slim, Large but Not Heavy w/ Detachable Window for Polarizer
Closest Focus and Magnification:	2.0m @ 0.17X	2.0m @ 0.17X	1.4m @ 0.24X
AF Drive:	Body Motor	Body Motor	Lens Motor (SDM)
AF Noise:	Very Noisy	Noisy	Silent
AF Speed:	Faster	Faster	Slower
AF Accuracy:	Good	Good	Not So Good
AF Hunting:	Most Noticeable	Less Noticeable	Not Noticeable
AF/MF Switching:	Push-pull Ring-form Switch - But with Limitation, i.e., Body's AF/MF Switch Needed to be at MF Position!	Push-pull Ring-form Switch - Without Limitation, i.e., Body's AF/MF Switch Can be at Either AF or MF Position	Quick Shift Manual Focusing - No Instant Push-pull Mechanism for Complete AF/MF Switching, but there is yet a Small AF/MF Selector
MF Feel (Damping & Smoothness):	Worse*	Better	Worse*
IQ:	Very Good (Best from f/6.7 to f/11)	Very Good (Best from f/6.7 to f/11)	Very Good (Best from f/5.6 to f/11)
Colour Response - Could be Subjective!: (1 Best, 3 Worst*)	3	1	2

* Remark: "Worst" and "Worse" are still Acceptable to Good! :-)

Some sample images of mine (w/ F*300 on K100D):-

Chinese Dragon Boat Racing


Read Also:-

Compatibility of DA Lenses on Full Frame

Summary Matrix for Equipment Tests and Reviews

The SDM Petition Online