Originally posted by 8540tomg Being able to shoot at ISO 1600 or higher with a faster shutter speed will make these older MF lenses much easier to use and much more valuable.
The K5 offers benefits that should be immediate with increased depth of field and much less camera shake to soften the image due to faster shutter speeds. In my case f16 to f22 is the sweet spot on my M 400/5.6. Sadly, I'm seldom able to work in this range as my subject, usually birds, like to hide in dark unlit areas. As a result I often shoot at 1/250 sec. around f8 and all the shortcomings of my optics are enhanced. Being able to double or triple the shutter speed and shoot at f16 has been something of a dream.
I have a preference to stay close to the native sensitivity of the sensor, and only with great reluctance crank the ISO- setting much above that. With the K 10 I considered ISO 800 to be the absolutely highest usable setting. With the K 7 I have occassionally used ISO 1600, both of these requiring a noise reduction run with Topaz DeNoise.
Right now I am processing pictures from my Indian trip. In some cases I just had to go up to ISO 3200 with the K 5. Sometimes I find it difficult to believe my eyes! The image quality and lack of noise is just amazing!
However, being able to use high ISO´s does not eliminate the need for fast shutter speeds. Freezing motion is a typical situation were you have to go for fast shutter speeds. Here lens speed often becomes significant. Of course being able to use high ISO´s gives you more leeway.
For people considering some of the long telezooms. There is a number of people here on the forum using these lenses. The characteristics of these lenses have been discussed, and are pretty well known.
Among the key things worth noticing are:
-of course having a zoom gives you flexibility with the focal lengths
- due to being somewhat slow these lenses sometimes have a tendency to hunt in AF, especially under low light/low-contrast conditions. K 5´s new AF module probably helps somewhat in this respect.
-the optical design of long telezooms is usually not optimized for the extreme end of the zoom range. Therefore they often lose some of their sharpness in the long end.