Why David Attenborough's people buy the expensive lenses

[fivemack]

(click and it gets bigger, but sadly in two cases no sharper; this is with the smallest and cheapest readily available large expensive lens, a second-hand Sigma 70-200/2.8 with 2x teleconverter. Picture 2 isn't too fuzzy, though f/11 isn't really enough for dimly-lit lions far away)

Also, in honour of Galileo:

Comments

[humanoid27.livejournal.com]

i took some (i thought) pretty good snaps of the moon years ago (circa '93) on the OM2sp using a tamron 500mm F8 mirror (catadioptric?) lens with a 3x converter. F8 was the only aperture on that lens, it wasn't adjustable.

(i may get another one if i find a decent one at a favourable price...)

[humanoid27.livejournal.com]

actually, i've just had a look at an original print as mentioned above and it's not that sharp. more like the F64 image.
i could say that i had a lot of difficulty focussing the neg (i didn't have a focus aid) but as they say... a poor workman... etc...
;)

[davidcook.livejournal.com]

Oddly enough, I had much the same idea (http://davidcook.livejournal.com/231620.html) about a week ago, but with a Pentax 300/4.5 plus 2x tele.
This is obviously how people develop the desire for a telescope, ideally with camera mount and motorised tracking :-)

[fivemack.livejournal.com]

I have a telescope, of the sort that is sold in high-street stores; the optics are made out of half-reasonable optical-grade cheese but rather less attention is paid to the mounting. The camera mount is on order.

Motorised tracking isn't a problem for the Moon and Jupiter, they're hundredth-of-a-second exposures anyway.

I borrowed a nice telescope from major_clanger, and used it twice in six months, so am not going to buy a nice telescope - maybe if I had a car which I could park securely with the telescope mostly set up in the boot, but I can't drive. There are a few places where you can go on holiday which have telescopes set up for you to use, and I'm tempted by that from time to time, though the one I know is in a particularly inaccessible corner of Portugal.