Zeiss 21mm f2.8 Biogon and Panasonic GH1

Leica M9 Zeiss 21mm f2.8 Biogon
We realise that we don't have many "fans" & our pictures are only average (/soundimageplus/2010/06/more-wide-angle-over-saturated-pictures.html)
but we persist nonetheless.

The headline image and the following are taken with this lens on the Leica M9.

Leica M9 Zeiss 21mm f2.8 Biogon

Leica M9 Zeiss 21mm f2.8 Biogon

Leica M9 Zeiss 21mm f2.8 Biogon

The very sharp results led us to test the lens on a GH1.

Test Shots - Panasonic Lumix GH1 + Zeiss 21mm f/2.8 Biogon M Mount lens

Test Shots - Panasonic Lumix GH1 + Zeiss 21mm f/2.8 Biogon M Mount lens

Test Shots - Panasonic Lumix GH1 + Zeiss 21mm f/2.8 Biogon M Mount lens

Test Shots - Panasonic Lumix GH1 + Zeiss 21mm f/2.8 Biogon M Mount lens

Test Shots - Panasonic Lumix GH1 + Zeiss 21mm f/2.8 Biogon M Mount lens

Test Shots - Panasonic Lumix GH1 + Zeiss 21mm f/2.8 Biogon M Mount lens

Excellent results. We did a test of this lens against the lumix 20mm f1.7. /soundimageplus/2010/04/m43-and-lenses.html

We concluded -
"We could not see any significant difference between the 20mm f1/7 and the Zeiss 21mm f2.8 in terms of sharpness. There was a slightly different colour balance but that was all."

However thats not the whole story. Together with the Novoflex Leica M > m4/3 adapter that we use we get true infinity focus with the 21mm on the GH1. i.e. The lens reaches infinity only when it reaches the infinity mark. Many modern AF lenses focus past this point. Apparently to prevent the lens becoming mechanically damaged by constantly jolting against its maximum focus point. Achieving infinity focus used to be easy - just rotate the lens to its maximum and you could be sure that objects in the distance would be in focus. Very handy for landscape photography. The Zeiss 21mm being an old design manual focus lens keeps this facility. In practice, it means that for a lot of outdoor photography in good light there is no need to constantly re-focus a lens. Stopping down brings more and more of the foreground into focus. A bright sunny day will easily allow apertures of f11 and often f16 plus a reasonably fast shutter speed at low ISO. Very useful for hand-held travel photography.

On m4/3 the 21mm (because of the 2x crop factor) produces an image equivalent to that produced by a 42mm lens on a camera with a 35mm equivalent (or full-frame) sensor. However it still has the same depth of field characteristics of a 21mm lens. Again handy for hand-held travel photography, allowing a bit more leeway for focusing and depth of field.

So in some ways this lens is much more useful than the the 20mm f1.7 lumix for what we do. Experience teaches you where to focus using an AF lens. The general rule if trying to get as much depth of field as possible is to focus approximately on a point one third of the way into the framed image. With apertures of f8 + this will in many cases work a good deal of the time. There is a technique using the depth of field scale on a lens (if it has one) to produce even more depth of field at a given aperture. This is called the hyperfocal distance. However this depends on the distance scale being accurate on a lens. Many are not. We tried it on the Zeiss and it wasn't particularly useful.

All in all using the lens on the GH1 proved very successful. In much of what we do it is important to obtain as much depth of field as possible. Using a manual focus lens can be very useful in this regard. Using a manual focus lens on m4/3 with the ability to use wide-angle lenses in a tighter crop is also an advantage. Its one of the reasons why m4/3 is such an attractive format for certain types i.e. landscape photography. It is more difficult to throw backgrounds out of focus with m4/3 unless you have very fast lenses with wide apertures. That is a disadvantage for some kinds of photography but a bonus for others, including a good deal of our work.