Using what you've got.....

[greypoint]

There are several interesting threads on here regarding the use of/what to buy etc., of long telephotos. I've never used more than a 400mm and was planning to look out for a used 170-500mm Sigma or similar to use this summer. To get an idea of the range I added my 2x converter to my 70-300mm and set it at 250mm - rubbish results but it gives a good idea of what you get in the frame. I'm now not so sure if it's worth spending the money. I add the tcon to my 80-200mm f2.8 to get the equivalent of a 160-400mm and still have the same sort of maximum aperture I'd get with the Sigma lens. It's a pretty good compromise but much more likely to suffer a touch of purple fringing than the APO Sigma. I've found the same with my Tamron 28-300mm - excellent in every way except sunlight on splashing water - so it's a case of hanging on to my Sigma 70-300mm for swan action!
So should i stop worrying about that extra 100mm - perhaps get another of the excellent 135-400mm lenses I used last year on the grounds they're so easy and lightweight [in comparison to my 80-200mm] and free of CA? Or should I hang on to my money - is a 135-400 really that much better than a 70-300 when the truth is, to get decent large shots of small birds you've either got to be very close or digiscope!
I'm sure Nikon will come out with a budget version of the D200 to replace the D50 at some point and I'd definitely want one of those! So is it really worth spending several hundred for that extra 100mm??

[postcardcv]

I guess if you are happy with what you've got then there's no need to spend money on a different lens...

Personally I know that I'd find a 300mm very limiting for bird photography and would want something more. I've used both the 135-400 and the 170-500 and both a good lenses. Personally I'd go for the bigger lens every time, as I want as much reach as I can get. That said what ever you do decide there will be times when you want more... Neither of these Sigma lenses work very well with tc's, so really the 135-400 would not be an improvement on what you've got.

The difference in weight and size between the 135-400 and the 170-500 is not massive, both are easy enought to use hand held, but you'll get better results if you use a tripod or other support. With the non-DG 170-500 currently selling at £399 on warehouse (though only for Nikon), it's one of the best value lenses around (even at £549 for the DG lens it's a good buy). Personally I think you're better off spending money on lenses than on upgrading your body, as the lenses will last a long time.

[BenBirding]

Go to a local camera shop, and try out some of the longer telephoto lenses. See which focal length you feel comfortable with.

[Keith Reeder]

Ben, there seem to be very few camera shops in the UK that carry stocks of long lenses that you can try - it always seems to be "we can order one for you..."

[BenBirding]

I'm glad to say that's not the case where I live. Sorry for not being helpful...

[greypoint]

Yes - no camera shops near me! It's not so much the weight or handling it's whether that extra 100mm is worth the outlay. My only reason for adding another 135-400mm to my set up would be it's better results in sunlight over my Nikkor + 2x. Mmm - I'll keep thinking!

[Keith Reeder]

It was helpful, Ben - if there were such shops to hand, what you suggested is without doubt the way to go...

[Keith Reeder]

For what it's worth, GP, I've mentioned in several threads that my current "reach" is more than enough for 99% of what I do - and for that other 1%, I'd want twice what I've got now...

[greypoint]

And wandering along the riverside first thing this morning it proved once again that the 300mm f2.8 that I get at the long end of my 80-200 attached to my D50 is quite long enough for most swan shots. The short end can be a problem when they fly low overhead - a couple of the headless variety unfortunately - nice bodies though!! My purchasing has followed a different track and it remains to be seen if it was a good idea!