New 70-300 f/4-5.6L IS extended length pic

[DavidEccleston]

The 300mm f/4L IS is effectively one stop faster (one less stop of aperture, 2-stop IS) - woodland critters often hold still, so high shutter speeds aren't always needed. Likewise, the new 70-300mm L lens will be effectively 3 stopsbetterthan the 200mm f/2.8 for still subjects, with it's 4-stop IS

True, the IS would work IF they hold still, and they're more likely to hold still with a 300mm than a 200mm lens. The 200mm f/2.8 wouldn't just be for getting a high shutter speed, but also for isolation, which the which the longer 300mm lens wouldn't be as good at. If I did opt for the 200mm, I could also turn it into a 280 f/4 with an extender, enhancing it's usefulness, but without IS that's going to need decent light that I won't find in the forest.


But, the new 70-300 is f/5.0 @ 200mm, so 2.333 stops better for still subjects, but also 1.666 stops worse for isolation. The 300mm f/4 isn't significantly faster than the zoom, and with worse IS, it seems like the wrong choice. It's worse than the zoom for static scenes, though likely a bit sharper, and only a touch better for action or isolation. Not enough of a difference to earn my dollars. Granted, it could also be paired with an extender, giving me a 420mm option, which could be nice.


My only hope is that photokina unveils some awesome new lens that makes my upgrade path clear.

If you're not averse to used lenses...

The used market is tough. Most EBay sellers, only want to deal with the US. In Ottawa, the people on the used boards tend to ask nearly full price, based on the price at Henry's, which tends to be one of the more expensive retailers. I can often find something new cheaper than used. The bargains are rare here, from what I've seen. Half my lenses, and my body are Adorama's Canon refurbs, so I'm not adverse to 'not-new' if I can get a decent savings.

[neuroanatomist]

The 200mm f/2.8 wouldn't just be for getting a high shutter speed, but also for isolation, which the which the longer 300mm lens wouldn't be as good at...But, the new 70-300 is f/5.0 @ 200mm, so 2.333 stops better for still subjects, but also 1.666 stops worse for isolation.

I'm assuming you mean for identical framing, e.g. 200mm f/2.8 at 10 m from the subject, or 300mm f/5.6 at 15 m from the subject. If you maintain the same distance to the subject, the isolation will actually be better at 300mm than 200mm despite the narrower aperture, since subject distance has a larger impact on DoF than aperture in these ranges. So, if you can get close enough to use the 200mm, and you have the 70-300mm zoom, you'll get better isolation with the zoom at 300mm f/5.6 than with the prime at 200mm f/2.8.


For example at 10 m distance to subject, 200mm f/2.8 will have a DoF of 26 cm. At the same distance, the new zoom at 300mm f/5.6 would have a 23 cm DoF - so, the extra 100mm of the zoom lens more than makes up for the loss of two full stops of aperture in terms of DoF.


Depending on what you're shooting and how close you are to it, you may actually need to stop down if you want to get the entire subject in focus - I run into this 'problem' with my 100-400mm, where at 400mm for a small, close bird I often need to stop down to f/7.1 or f/8 to get the whole bird in focus.


Here's hoping there are more lenses announced for Photokina - personally,I might be tempted by a 50mm f/1.4 II, butI'm really hoping for a 35mm f/1.4L II...


--John