Originally posted by Sandy Hancock I have used the DA*300 on the K-1 quite a bit, and can confirm it works superbly in Full Frame mode.
When I need more reach than I could get with cropping I use the Pentax HD DA teleconverter in Crop Mode (or on a crop body).
Thanks Sandy...appreciate that.
---------- Post added 04-23-18 at 06:55 PM ----------
Originally posted by clickclick I'm playing with the Pentax-F 1.7x AF on my K-1. In general, I think I'm liking it, but need to do more testing. I have used the DFA 150-450, DA 60-250 and DA 50-135. In some attempts at detailed comparisons, I did some shots with the 150-450 where i resampled to match with and without the adapter. It was mixed, Some shots were better with the 1.7x, and some were better just upsizing. It left me feeling I need to run through some more paying close attention to aperture to see if there was a sweetspot for the 1.7x, and I think there was. I also want to do some testing with primes. You will also note that I have played with the DA 50-135, which on it's own vignettes badly on full frame, but with the 1.7x, it does fine. Actually makes sense that the 1.7x magnification takes a piece of the smaller image circle and makes it big enough to cover the full frame format - pretty cool!
So bottom line is the 1.7x will give you full frame coverage, and it may or may not be better than just upsampling your image. You may find you can also now use crop lenses. It does introduce a lot of CA, and you'll want to remove purple fringing in post. I'd say if you suffer from LBA and want to play and have the funds, it may not be bad to look for one. If you're on a budget and want max bang for the buck, I can not recommend it over saving up for the DA* 300.
Thankyou, already have the lenses, its the body I am adding to the arsenal. Appreciate the info. Cheers