Originally posted by ivanvernon I actually am a prime lens shooter, and do not use zooms except when image quality is a secondary concern--parties and similar occasions, famiy picnics, etc. For that reason, I can say very little of value about zoom lenses.
The lynchpins of my stable of primes are the so-called three amigos--the 31, 43, and 77 limited lens trio. I have lots of other primes as well, and have grown quite accustomed to zooming with my feet. The 77 and the 31mm lenses are great Pentax glass, and consistently deliver to me the greatest percentage of keepers than any of my other lenses. Moving from the crop sensor K-3 to the full-frame K-1 will affect my use of these prime lenses. It will make the 77mm more useful since it will be a wider lens, and more useful for indoors use rather than being more of a short telephoto for outside use. I am not quite sure about the 31. I will be using it differently.On the K-3. it was a great normal lens, but on the K-1 it is definitely a wide angle lens. However, so far I really like the results I am achieving with this lens for the two days I have been using it. I will attach one of my landscape photos that will show what this lens can do. The lens now on K-1 is effectively equivalent to the 21mm on the K-3.
Hope these comments and photos are helpful to you in considering your decision.
Thank you for your reply. Back in the 1960's and '70's I was also mostly a prime lens user. I got into zoom lenses when I bought a Pentax 35-105 A Macro lens . It was convenient.
In the film days aside from my Pentax gear, I also used my old Leica Rangefinder, with it's 50 mm Elmar. Great combo.
I do some landscape work, but primarily use my wide angles for a lot of vintage vehicle photography.
You've given me a very good idea.
I have a 21 mm Limited and as you pointed out, the 31mm on the K-1 body gives an equivalent field of view to a 21mm on an ASP-C body. For the next while I'm going to work with my 21 on my K-5...and through actual usage, see if that field of view meets my needs.
BTW, excellent landscape photograph .
Your comments and perspective have been very helpful.
Thanks again,
Les