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Patent: EF 20-45mm f/2.8-4

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Who Dey
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A patent for an optical formula of 20-45mm f/2.8-4 has appeared. <a href="http://www.northlight-images.co.uk/Canon_new_lenses.html" target="_blank">As suggested at Northlight</a>, this sort of optical formula could end up being a 17-40 type of replacement, or even part of the new EF 16-35 f/2.8L II development.</p>
<p>Patent Publication No. 2015-197593 (Google Translated)</p>
<ul>
<li>Published 2015.11.9</li>
<li>Filing date 2014.4.1</li>
<li>Zoom ratio 2.25</li>
<li>Focal length f = 20.00 23.60 45.00</li>
<li>Fno. 2.75 2.90 4.16</li>
<li>Half angle of 47.25 42.51 25.68</li>
<li>Image height 21.64 21.64 21.64</li>
<li>Overall length 158.28 156.32 173.36</li>
<li>BF 42.05 46.10 73.14</li>
</ul>
 
Interesting zoom range. Would be even more interesting on crop as a general purpose zoom (32 - 72 mm eq.).

I don't expect this to become a product but if so I#d be really interested in the sales numbers.
 
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This is a very useful range. I find myself using the Shorty Forty a LOT as my "normal" lens. I still haven't mastered the art of UWA (20mm and shorter on FF) composition. My favorite landscape length is pretty much 24mm to 50mm.
 
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would a 20 45 2.8 - 4 patent separately cover a 20-45mm 1:2.8 &/or a 20-45mm 1:4, although I would expect a 20 45mm 1:4 to include IS


I would probably buy a 20 45 L lens if it had consistent IQ along the full zoom range
 
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Hopefully it will result in a similar product with Image Stabilization ... for me this range is a no brainer if IQ is stellar. I really like the 2.8 40 but sometimes need a little bit wider ...

The just 10 lens group config allows for very low flare if combined with modern anti reflective layers. Maybe that is one part of this patent: Reduce glasse-air surfaces to increase contrast under extreme lighning conditions ...

Hopefully it is complemented by a f/4.0 40(50)-200 L IS USM with 1:2.5 max reproduction ratio. This would be my understanding of a very versatile 2 lens 2 body combo.
 
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The specs look similar to the EF20-35 f/3.5-4.5 (non-L) I had previously.
Great little lens. Sharper than my EF20 f/2.8. I found the f/4.5 limiting at 35mm.
I'm enjoying 20mm again with the Voigtlander. Wider than 24mm and more usable than 14mm.
 
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moreorless said:
You could argue this wouldn't be an entirely "new" focal length for Canon as I'v heard a few ASPH shooters say they loved the range a 16-35mm gave them on that format which would be near identical to a 20-45mm FF lens.

My 16-35 f2.8 MkI practically lived on my APS-H cameras, mainly because that was as wide as I could go with 2.8 zooms and it didn't use the weak corners. But the range from an effective 21-45 is pretty limiting and the 24-70 was too long at the wide end. I am so glad that bastard sensor size is dead.
 
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