Originally posted by Paul the Sunman A quick check on B&H shows 34 off-brand FF lenses available for Pentax K-mount. For comparison, there are 110 for Canon and 111 for Nikon.
I believe this is a major inhibitor for general uptake of the K1. Intrinsically, it's an excellent camera, but why buy into the Pentax FF eco-system with such limited (and often ageing) 3rd party support? The new Pentax FF zooms are great, though expensive and large. They won't suit everyone, or cover every need.
So, perhaps PF members would like to nominate which 3rd party FF lens they would be most keen to see in K-mount (that is not already available). I'll start the ball rolling with the Sigma 150-600 Sport (yeh, I know, large and expensive).
My perspective....
I own 18 lenses, 34 off brand lenses compared to 111. Really? I'm supposed to care?
Of the lenses I own most are Pentax.
My Sigma 70 macro, I'd like to sell and get the Pentax 100 macro. The Sigma is too heavy.
The Sigma 8-16 is my goto UWA lens.
The Tamron 90 is an amazing lens, but my wife has hi-jacked it.
The Sigma 18-250 sucked so bad i gave it to my step daughter.
If you really want 600mm put the 1.4 on the 150-450 and you have a great lens.
This an issue I really don't care about. Give me a camera I'll take a picture. What ever the issues are, I'll figure them out. As far as the third party long zooms go, as far as I can tell, the Sigma 50-500 is the best of the lot, and it's still available in Pentax mount.
You guys realize that if you're shooting a k-5 you can get more subject resolution increase by upgrading to a K-3 than you can by going from a 500mm lens to a 600mm lens? And the things is, your 600mm 6.3 lenses probably won't use a TC. The Pentax 150-450 5.6 will. You just have more potential with the Pentax.
Pentax 150-450 with 1.4 TC 630mm and ƒ8. Until I get to that point, I can get to 478mm with my DA*200 and stacked HD DA 1.4 Tc and F 1.7 AF adapter. Which to my eye appears to be sharper than the any sigma 600 or 500mm zoom.
I tend to see FL in terms of being meaningful if you double it or at least 50% bigger.
So, 200 -300 is 50%, possibly worth doing.
200 to 400mm , definitely worth doing.
400-600 possibly worth doing.
400 -800 definelty with doing.
500-600.... not worth 50 bucks to me, in fact between those two choice I'll stick to the best price, since what i really want is the 150-450 plus TC.