LensTip.com

Lens review

Carl Zeiss Touit 12 mm f/2.8

30 August 2013
Arkadiusz Olech

7. Coma, astigmatism and bokeh

The coma makes itself felt quite strongly at the maximum relative aperture and it contributes greatly to limiting the resolution values on the edge of the frame there. Fortunately, on stopping down by 1 EV the aberration becomes moderate.

Carl Zeiss Touit 12 mm f/2.8 - Coma, astigmatism and bokeh


The astigmatism decreases on stopping down in a truly textbook fashion. At the maximum relative aperture it is still noticeable, reaching 10%; after stopping down the aperture to f/4.0 it is reduced to a very low level of less than 3% and by f/5.6 that aberration becomes imperceptible (below 1%). The average value, on all testing charts and in a distance of 3 EV from the maximum relative aperture, amounted to 4.7% which allows us to state that the tested lens doesn’t have any problems with this off-axis aberration.


Please Support Us

The coronavirus crisis has been adversely affecting many businesses and, sad but true, ours is not an exception. Despite that difficult situation we would like to preserve continuity and high quality of publications available on all our websites. Still, we are now aware it might be impossible without additional financial help. That's why we would like to ask all those who visit, read, and care about Optyczne.pl, LensTip.com i Allbinos.com for support - it's enough you send us a small sum of money via PayPal. If a lot people decide to support our websites we think we'll stand a chance and survive next months without any lasting harm. We count on your support and understanding, stay safe and be healthy.

- - - - - - - - - - - - - - - - - advertisement - - - - - - - - - - - - - - - - -

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Defocused light points don’t look perfect – in the centre of the circle you can notice a darker area and a noticeable rim on its edge. Still, due to the parameters of the tested lens and its usage, you won’t admire large defocused areas in your photos very often so it shouldn’t be a problem.

Carl Zeiss Touit 12 mm f/2.8 - Coma, astigmatism and bokeh