Hi Bruce - I'm going to suggest that as the focal length doesn't actually change, there's no extra magnification of movement, and so neither should your rule.

But, I'm not so sure the rule should be considered absolute anyway. So there are a few other things you can practice with to get the shutter speed down too.
These would include good posture and stance. The Jo McNally hold. Good camera holding technique. And good breathing technique. A lot of this stuff is also taught to military snipers.

Now I find that panning changes some of the dynamics too, giving a crisp subject against a motion blurred background at slower than the rule shutter speeds. And I think sometimes, so can burst shooting, on some of the faster cameras.

With and without modern IS, I seem to be able to hand hold 300 and 400mm lenses at 1/125 and below in less than optimum lighting. Now I get a lot less keepers, but I can get enough, and its a good to have technique up your sleeve.

Phil

Hi Jenz,

I use an 80D for birds. And I also use a 1DIV.

I use the EF 400, the EF 100-400 and the EF 300, all with extenders as well.

The 80D is great, with some nice AF tracking capability. And for BIF, can extend the AF use of the EF 100-400 with x1.4 over the 1DIV.

The 80D with the EF 400 f5.6 is a neat BIF combo - light, fast and accurate.

These are examples of the 80D with the EF 400 maintaining focus while panning across a 'contrasty' background.

Phil

Hi Mark

My lightweight kit (if birds involved) has been an EFs 15-85 and an EF 70-300 (the first version). It has also been my travel kit if I felt might need anything longer than the 85mm. I had a play with the second version, and if I didn't own the first version, I'd get that one, but I couldn't see any need to upgrade.

As its main attraction to me has been its lighter weight, I haven't used it much on a FF, but when I have it has paired nicely with my EF 16-35 (maybe with the EF 40 f2.8 pancake on my person) or the EF 24-105. I don't have a 5DIII, but just by the way, when mounted on my 1DIV, it all feels a bit less balanced than same with an EF 300 f4. I'm sure that's just me though.

I think its a pretty good lens. As you'd expect, its just not quite as sharp as my EF 300 f4, which is twice the weight. Mine is also just a bit soft above 280/290mm, (and I thought the vsII that I played with for a few days was the same) but still quite usable, but overall, perhaps not the lens I'd choose first to produce 20x16 prints involving feathers.

I'm thinking of selling it though, as I've now got an EF 70-200 f4 IS which is giving it a bit of a run. Its a bit heavier and just that little bit short, but it does focus a bit faster, (especially in AI Servo). I think the IS implementation is a bit better and it works well enough with the x1.4 TC, producing pretty similar IQ and AF speed to the EF 70-300.

But the EF 70-300mm f/4-5.6 IS USM Lens is a sort of 'just right' lens for me (on a crop), so its not so easy a decision to sell it. So I'd recommend you consider it.

Phil

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I always have problems with the details :-)

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Yep - and so did I :-)

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Thanks Guys

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