[normhead]

SItting in my porch set up… my A400 seems a little to tight, its hard to keep both the tail and the head in the frame.



Next up my 60-250, the field of view shooting at 250mm, it's way too wide


So, I pulled Tess' F-70-210 out of the cupboard more what I wanted, big enough for detail in the bird, lots of room to crop that 24 MP file.



Lens makers could make this a lot easier for us by rating their lenses at say 20 feet. so that at a reasonable shooting distance 210mm doesn't give you more magnification than 250mm.

[Eric Auer]

Cool comparison.

I just recently got a -F 70-210mm from a Forum member and very happy with the results from it so far.
But damn if it isn't Loud!

[normhead]

Cool comparison.

I just recently got a -F 70-210mm from a Forum member and very happy with the results from it so far.
But damn if it isn't Loud!

I was so surprised these birds weren't flying away because of the noise, but they didn't seem to mind. I guess they're used to me.

[Adam]

SItting in my porch set up… my A400 seems a little to tight, its hard to keep both the tail and the head in the frame.



Next up my 60-250, the field of view shooting at 250mm, it's way too wide


So, I pulled Tess' F-70-210 out of the cupboard more what I wanted, big enough for detail in the bird, lots of room to crop that 24 MP file.



Lens makers could make this a lot easier for us by rating their lenses at say 20 feet. so that at a reasonable shooting distance 210mm doesn't give you more magnification than 250mm.

How were you able to get in closer at 210mm than at 250mm?

Adam
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[normhead]

The F70-210 is an older style zoom that extends the barrel to focus, think of it as having your lens on an extension tube. As the front element moves out, the magnification increases. On an internal focus lens, the front element stays put and the internal elements focus. So when you're a long way from infinity, the images are not as magnified. The lens barrel is extended about 2 inches, on the 70-210, and you get the same kind of magnification you'd get with a two inch extension ring.

All the older lenses are like this. My Sigma 70-300 does this. To some extent my 18-135 does it, but not as extreme as the 70-210. At 8 feet, my DA*60-250 @ 250 is about the equivalent of a 135mm prime.

The downside to this is put the 1.7 TC on the 70-210 or 70-300 and the purple fringing is out of control. You get purple fringing because they are older lenses, you get it worse because they magnify up close, and then magnify it again 1.7 times, and you get a lot of unusable images.

[NZ_Ross]

The F70-210 is an older style zoom that extends the barrel to focus, think of it as having your lens on an extension tube. As the front element moves out, the magnification increases. On an internal focus lens, the front element stays put and the internal elements focus. So when you're a long way from infinity, the images are not as magnified. The lens barrel is extended about 2 inches, on the 70-210, and you get the same kind of magnification you'd get with a two inch extension ring.

All the older lenses are like this. My Sigma 70-300 does this. To some extent my 18-135 does it, but not as extreme as the 70-210. At 8 feet, my DA*60-250 @ 250 is about the equivalent of a 135mm prime

I have learnt something new and interesting today. Thanks for sharing this info