I'd really like to have a wide angle lens to do some photography that just normally isn't possible due to an effective (135 format) 28mm with the ZD 14-35mm and ZD 14-54mm lenses. My iPhone 4S is the only way I can get really wide angles currently. Panasonic's 12-35mm is available but an effective 24mm vs. 28mm isn't a huge difference. (Update: Equally, the new Olympus 12-40mm f/2.8 will be available in November but is it enough?) Would it be useful with the GH3? Sure, but it would be only somewhat more useful in wide angles and not enough to justify the price.
I had considered the Nikon D7100, but even then, it has the 1.5x multiplication factor, so a 10-20mm becomes effectively (135 format) a 15-30mm lens. Before I jump to a Nikon D700 or D800, I need to consider how often I'll use such extreme wide angles. Paying US$4000-5000 to get wide angles may be a bit much.
Olympus and Panasonic have a few options:
- ZD 7-14mm f/4.0 (Four-Thirds)
- Panasonic 7-14mm f/4.0 (micro Four-Thirds)
- ZD 11-22mm f/2.8-3.5 (Four-Thirds)
- ZD 8mm f/3.5 fisheye (Four-Thirds)
- Panasonic 8mm f/3.5 fisheye (micro Four-Thirds)
- m.Zuiko 12mm f/2.0 (micro Four-Thirds)
- ZD 9-18mm (Four-Thirds)
- m.Zuiko 9-18mm (micro Four-Thirds)
- m.Zuiko Pro 12-40mm f/2.8
- Panasonic 12-32mm f/3.5-5.6
Those are plenty of options, I suppose. The 9-18mm are out immediately. They lack weather-proofing and they're not very good. The Olympus m.Zuiko 12mm f/2.0 is a great lens but lacks weather-proofing and I generally don't buy primes because they don't fit most of what I want to photograph. Yes, I know how to walk and my first few lenses ever were fixed focal length lenses. The fisheye lenses are similarly out of the list, although Olympus has a $200 discount on its lens currently and it's weather-proofed, so it is somewhat interesting. Of course, they have a distorted view, which makes them both loved and hated.
That brings me to the 7-14mm lenses. Panasonic really outdid themselves creating a small version of Olympus' lens. Despite the lack of weather-proofing, it seems a wonderful lens and it's built very well, especially compared to other micro Four-Thirds lenses. The ZD 7-14mm is practically perfect with weather-proofing. Yes, it's huge but it works on two systems with an adapter, and Adorama has a demonstrator occasionally at an amazing price. The low light capabilities would be significant, as this would be a good lens for interior shots. Unfortunately, at f/4.0, you can't do much indoors without extra lighting (or a great deal of exposure and clean-up time).
I'm thinking that the ZD 11-22mm f/2.8-3.5 is a good choice. It's mildly wide with a good maximum aperture, and it's reasonably light. The 72mm filter size will require an adapter ring but that's not a huge deal. The MTF graphs are unusual, as Olympus didn't label them very well. It looks like the 11mm graph is a bit wild, but I would expect distortion at such a focal length. (Update: seeing Robin Wong's photos with this lens, I expect it to be quite amazing, as it came from the time when few lenses existed, such as the 14-54mm f/2.8-3.5 and the 50-200mm f/2.8-3.5.)
Panasonic's new 12-32mm f/3.5-5.6 is an amazingly small lens, made for the GM1 camera body, which is also amazingly small. The maximum aperture is also small, mainly because it's a kit lens, but it may be quite usable because of high ISO sensitivities on newer bodies.
Olympus' new 12-40mm f/2.8 lens is absolutely wonderful. If there is a flaw, I'm not sure what it is. The included lens hood looks a bit small, but from my experience with the 14-54mm f/2.8-3.5 hood, the lens hood should not be in the photo as it is with the 14-54mm hood.
I'm still lost in thought about this. When I need wide angles, it's apparent that I don't have the equipment but most of the time, it doesn't matter enough to spend extra money. Of course, I could have started with Nikon 135 format digital equipment back in 2004, but oh wait, it wasn't available. Their APS-C based equipment wasn't all that great then, either, nor was Canon's.
Update 2014.03.10: Recently, Olympus announced a micro Four-Thirds version of the 7-14mm but with a larger maximum aperture--f/2.8. I'm sure the lens will be good, if it actually arrives. It's due in 2015, which is next year, but that would be any time next year. I recently bought the 12-40mm f/2.8 and the 12mm end has been a thing of joy for me. I've been able to photograph a much wider scene than the extra 2mm would seem to allow--or in 135 Format terms, 4mm.