Shooting a New Lens — Focus

2012-02-24 • SEND FEEDBACK |
Related: gear, Leica, Leica M, Leica M lenses, Lenses

Thanks to LensRentals.com, I have the Leica 21mm f/1.4 Summilux-M ASPH and the 28mm f/2 Summicron-M ASPH available for comparisons and testing when I head to Death Valley soon.

Leica 21mm f/1.4 Summilux-M ASPH and Leica 28mm f/2 Summicron-M ASPH

Focus check

With the Leica M9, the VERY FIRST thing one should with a new lens is to verify accurate focus with the lens on your particular M9. Rangefinder focus is a mechanical coupling and there is no guarantee that it is correct for any particular lens/body combination, even if the lens is brand-new out of the box.

As I show in Rangefinder Focus Error With Brand-new Lens in my didactic and essential Making Sharp Images, the serious photographer cannot assume that a brand-new lens focuses accurately.

So the first thing I did with the two rental lenses was to verify focus accuracy, shooting both lenses wide open on 6-10 images at varying distance, then checking focus accuracy in Photoshop after downloading the images.

Always make a focus-accuracy test wide open, otherwise depth of field masks the error. Besides, what’s the point of a 21/1.4 or 28/2 lens speed if one doesn’t shoot wide open at least some of the time? And focus must be perfect at f/1.4 or f/2 or the image will be degraded, perhaps to throw-away status. With the Leica M9, I also stack the 1.25X and 1.4X viewfinder magnifiers to rule out any user error (my eye).

Crops below are actual pixels from the center of the frame. Focus was spot-on for these frames and my other test images, so the lenses are good to go for comparisons and testing.

The sharpness of the 18-megapixel images makes me lust after a 36-megapixel Leica M10 someday. Why not? The lenses can handle it, and Nikon has already proven that the sensor technology has arrived.

Actual pixels with Leica M9P + Leica 21mm f/1.4 Summilux-M ASPH @ f/1.4

Actual pixels with Leica M9P + Leica 28mm f/2 Summicron-M ASPH @ f/2

See also :

• Lens Performance: What Matters
• Which Wide-Angle Lens is Best?
• Blur Can Be Beautiful
• Lenses as an Investment; Electronic Lenses vs Manual Control.
• My Reference Lenses For Testing Sharpness.
• Shooting a New Lens — Focus.
• What Does Depth of Field Mean on a 36 Megapixel Camera?
• Nikon D800 / D800E — Which Nikon Lenses?
• Reader Comments on Lens Reviews.