Originally posted by reh321 Canon's system is conceptually different, and there is no easy way to compare. I don't have any lens catalog memorized. but I believe Canon has many fewer prime lenses than Pentax does. On the other hand, I don't hear Canon users complain about "gaps" in their lens lineup as I do from Pentax users
Just doing a quick search on B&H Canon has 68 full frame lenses and 18 APSC, 44 zoom and 41 primes. Pentax has 15 Full frame 34 apsc with 21 zoom and 28 primes. Total lenses in EF mount including third party is 279 and Pentax K mount including third party is 119.
I added the Canon system last year to my collection with the plan on keeping my K1 and 300mm and below lenses and just having the big lenses with Canon.
At the time I had a K1 and K3 with the DA560, DA*300, DFA 100 macro and da 50 and 35. I sold off the K3 and da560 and picked up a 5dsr and 600mm F4 IS II to replace them. Then I was looking for a 70-200 2.8 and was looking at both Pentax and Canon and I just couldn't find any good reviews on the Pentax anywhere except on this forum but could find tons of reviews on the Canon 70-200 IS II. So I decided to sell the rest of the Pentax and picked up the Canon 70-200 and a 7D2 body. I have since added a 16-34 F4 L IS to the collection and have the 400 2.8 budgeted for 2019.
Of all the Pentax lenses I had the DA* 300 was by far the best especially on the K1, wish I could've kept that combo. I think that lens was almost as good as the Canon 70-200, and I've been really impressed with the Canon. The da560 you can't compare with the Canon 600 F4 IS II. I know people will say well the canon cost a lot more and it does, but when the 560 came out it was $8000 so it was a little closer in price and in no way was it worth $8000.
Canon does have a much larger selection and in a wide price range. They seem to offer lots of lenses in a variety of speeds, 16-35 F2.8 16-35 F4 and 70-200 2.8 and 70-200 F4 and so on and the used marketplace is much larger because of the number of Canon users compared to Pentax.
I wish I could've kept my K1 and DA*300 it was a great little carry around combo and the images were great but at the time it didn't make sense to keep two systems and until I fill out the Canon line up it's not in the budget.