06-08-2012, 04:17 PM
[quote name='Brightcolours' timestamp='1339153014' post='18770']
I am not too surprised about that... It is the only STM zoom they offer. If they want to make a big point of the hybrid AF system for live view, it is the only option, and it would be stupid to have the only option have the not so great performance of the old 18-135mm.
The optics have changed quite a bit:
Old 18-135mm:
New 18-135mm STM:
The 40mm f2.8 TSM does not have half bad MTFs either (for a pancake):
![[Image: mtf.png]](http://cweb.canon.jp/ef/lineup/standard/ef40-f28stm/img/spec/mtf.png)
Here is the lens construction:
![[Image: lens-construction.png]](http://cweb.canon.jp/ef/lineup/standard/ef40-f28stm/img/spec/lens-construction.png)
[/quote]
Interesting little lens; looks like a Tessar-variant with ideas borrowed from a double Gaussian design. I guess that is why it is F/2.8 only. I would expect reasonably good bokeh from it. We'll have to see <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='
' />.
Kind regards, Wim
I am not too surprised about that... It is the only STM zoom they offer. If they want to make a big point of the hybrid AF system for live view, it is the only option, and it would be stupid to have the only option have the not so great performance of the old 18-135mm.
The optics have changed quite a bit:
Old 18-135mm:
New 18-135mm STM:
The 40mm f2.8 TSM does not have half bad MTFs either (for a pancake):
Here is the lens construction:
[/quote]
Interesting little lens; looks like a Tessar-variant with ideas borrowed from a double Gaussian design. I guess that is why it is F/2.8 only. I would expect reasonably good bokeh from it. We'll have to see <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='
' />.Kind regards, Wim
Gear: Canon EOS R with 3 primes and 2 zooms, 4 EF-R adapters, Canon EOS 5 (analog), 9 Canon EF primes, a lone Canon EF zoom, 2 extenders, 2 converters, tubes; Olympus OM-D 1 Mk II & Pen F with 12 primes, 6 zooms, and 3 Metabones EF-MFT adapters ....