Is it possible??
Yes!
One of the attractiveness of the Pentax K-mount is its backward compatibility with with 25+ million (!!!) PENTAX K-mount lenses spanning decades. This number was announced during the launch of Pentax mirrorless camera K-01.
Further more, this number does not include the ever common M42 screwmount lenses that have the same focal flange distance of 45.46mm that can be used with a simple cheap adapter without losing infinity focus.
WHY?
1. Most of them (except for some rare ones) are much cheaper than the Auto Focus ones. Imagine a Pentax SMC-M 50mm F2 prime lens only at S$50.
2. They are widely available and easy to find as third party lens manufacturers were common and many SLR cameras like Ricoh and Chinon utilized the K-mount.
3. Most of these lens are better built (note: metal and glass => heavier) than those plastic ones you see now.
4. Optical quality are exceptionally outstanding for most of them.
WHERE?
Mostly on second hand market as these are not in production anymore.
HOW?
Get yourself any Pentax lenses in your local second hand market with K-mount and discover the fun. Turning the focus ring makes you feel like a pro-shooter! I have a few manual K-mount lenses from Ebay but no M42 ones yet.
Mounting the lens is the same as usual but you have to change some settings in your Pentax K-r. See link here:
support.pentaximaging.com
1. Turn on your K-r and remember to input focal length for Shake Reduction to work correctly. Note that this is in 35mm equivalent. Eg, 50mm prime lens is 50, not 75.
For zoom lens, take the closest value to the midpoint. Eg, 135 (140 not available) for a 80-200 zoom.
2. Mode: Set to Manual mode.
3. Set the Aperture value on your lens (not screen) by turn the aperture ring on your lens.
4. Manual focusing:
Method 1. By sight - Using viewfinder to focus by turning the focusing ring to and fro until you "SEE" the focused point is at its peak focus.
Method 2. By red indicator - In the viewfinder, the red focus indicator will light up when the object (where the indicator) is in focus when shutter is half-pressed.
Method 3. Catch in focus- You can set K-r to take the shot once the object is in focus while you turn the focus ring under Custom menu. Note that the shutter button must be pressed all the way down during the whole action.
Turn the focus ring very very slowly. This prevents the shot from be taken at the point where you overshoot the focus area.
Method 4. Using Live view - Switch to live view and focus. To zoom in, press the 'INFO' button to see more clearly if the object is in focus.
Other methods: Changing the focusing screen to one with split screen indicator with the stock one in your K-r. Image is in focus when the images are aligned in split screen. Warning: I have not tried this yet but others have.
5. Taking the shot:
Remember to press the green button once for stop-down metering for an accurate exposure. This allows the meter to "read" the amount of light reaching the sensor.
Trick: You can actually switch to "Av" mode after 1 stop-down metering. You notice that the shutter speed will change accordingly to the different lightning conditions provided your aperture value is constant.
Then press the shutter all the way to take the shot.
Tada! Shot taken using manual lens....but that's not the end.
If you are using method 2 or 3, take a look at your shot, is it is Out Of Focus (OOF)? Example in portrait photo, the nose area is sharper than the eye although you focused on the eye.
Is it due to object movement or hand shake? Check by taking static objects (removed object movement) with the K-r on the table with 2sec delay timer (removes hand shake). If it is not due to the 2 factors mentioned, it could be due to AF misalignment.
For me, my AF lens focal point differs with my MF lens. My DA 35mm F2.4 need AF adjustment (Value +10) but my MF do not need them (value 0). So I have disable AF adjustment whenever I use MF lenses.
Once you got the focal point correct, Enjoy!
