Originally posted by Stark Raving Mad Hello all,
I am shooting with the K-S2 and K1, mostly older lenses. M's, A's and just started with the M42's. Was wondering if there was an advantage in the 645 A's on the K-1? I have to be pretty thrifty and noticed decent pricing on some of the 645 A's I've come across. I shoot because I love it and to make a few extra dollars. In particular I'm trying to find the best lens for shooting old structures in good light and then portrait's as a secondary. Is there an advantage with pairing the 645 lenses to the K-1 or just stick with the K and M42? I love a lot of the photos shared here and figured if anyone knew I'd find an educated answer here.
Very good question. Price, value, and image quality are advantages with many of the lenses. Disadvantages may include lack of auto-focus, greater size and weight, and lack of shooting modes. With 645 and 67 lenses on your K-1 and S2, you will only be able to shoot in M and AV modes. Image quality is generally quite good as you are only using the center of the larger lens where image quality is always at its best. One thing to bear in mind is field of view (FOV), which will be different for a medium format lens when mounted on full frame or crop sensor cameras. Take the 645/55mm, for example. Its FOV on the 645D or Z is approximately equivalent to that of a 34mm wide-angle K-1 lens. However, if you mount the 645/55mm on the K-1, the FOV constricts to approximately 88mm, which is short telephoto territory. This means obviously that you have to select the 645 or 67 lens based on what FOV you wish to attain.
In my experience, the 67/55mm is a great lens for my flower photography, as is the 645/120mm macro lens. For portraiture there are lots of choices--the 45mm, 55mm, 75mm all ought to work on the K-1 or S2, though they would be a little longer on the S2.
Shooting structures may be more difficult because you need a wide angle lens, and very few of these lenses will remain wide angle when mounted on the K-1 or the S2. The excellent 645/35mm, for example, becomes a normal lens equivalent at something like 55mm. A better alternative would be something like the Penax-DA 10-17mm f 3.5-4.5 fisheye, which is almost rectalinear at around 15-17mm and can be defished in post processing if desired. It is a crop sensor lens, but still can be used on the K-1 in the 14-17mm range with hardly any vignetting.You can also use it in crop mode on the K-1, of course, or shoot in square format if you have updated the K-1 firmware.
I hope these comments will be helpful.