The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Lensbaby Burnside 35 and the Pentax 40mm F2.8 L for their suitability to various photography scenarios:
Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Lensbaby Burnside 35 is the longer of the two lenses at 70mm. The Pentax 40mm F2.8 L with a length of 15mm is 55mm shorter. Besides being longer, the Lensbaby Burnside 35 also has a larger diameter of 70mm compared to Pentax 40mm F2.8 L's 63mm diameter.
Weight of a lens is as important as its external dimensions, especially if you are planning to hand hold your camera and lens combination for longer periods. Pentax 40mm F2.8 L weighs 80g, 78% (294g) lighter than the Lensbaby Burnside 35's weight of 374g.
Below you can find the dimension and weight table of the 'Standard Prime Lenses in Pentax KAF Mount for size comparison purposes.
Standard Prime Lenses in Pentax KAF Mount for Size Comparison
Both Lensbaby Burnside 35 and Pentax 40mm F2.8 L has the same Pentax KAF lens mount. Some of the latest released cameras that are compatible with the Pentax KAF lenses are Pentax KF, Pentax K-3 III and Pentax K-1 II.
Lensbaby Burnside 35 is also available in Canon EF , Fujifilm X, Micro Four Thirds, Nikon F (FX), Samsung NX, Sony Alpha and Sony E mounts.
Pentax 40mm F2.8 L is also available in Pentax KAF mount.
Lensbaby Burnside 35 is a prime lens with fixed focal lenght of 35mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides an 35mm (FF) equivalent of 52.5mm.
Pentax 40mm F2.8 L is a prime lens with fixed focal lenght of 40mm which has a 35mm equivalent focal range of 52.5mm when used on a APS-C / DX format camera.