Had an interesting encounter yesterday with a fellow birder while at the Barker Inlet wetlands.
I was sitting just off the path photographing some terns when I heard a noise and looked up to see a guy standing on the path with tripod,camera, large lens etc.
Having said hello we got to talking and as I could see he had Nikon gear I took the opportunity to ask him about his gear as I am making early enquirys into a camera/lens upgrade.
I have had my D600, 300/4 1.4 tc combo for a couple of years and am thinking of investing in a longer lens for various reasons.
Turns out he had a D810, 500/4 combo, close to what I have been investigating (D800e,500/4)
He said he had the D800e before he bought the 810 and the only difference he could tell was a slight but noticable increase in focus speed.
He was kind enough to let me take a few shots of a distant Great Egret then after I handed his camera back we both got to take some shots of a hovering Whiskered Tern so were able to compare shots.
The 300/4 is no slouch as far as focus speed and IQ but this 500/4 was mind blowing!
Sooo sharp and fast. Of course cost and weight are miles apart but that wasn't my interest, just wanted to see the difference in IQ.
We talked for a while about his choice of the 500 over say a 600 and I came away from the encounter with a better insight as to why the large primes are so expensive, and that you really have to make the case for the purchase. Now to start saving 
Hi Rick.
I cannot comment personally on the equipment you speak of as I am a Canon user.
It's a simple fact that if you want the best quality images you need to lay out considerable money.
About a year ago I upgraded to a Canon 5D Mkiii and do quite a lot of bird photography my lens of choice is the sigma 300-800 lens.
I would say I use it a t the 700-800 range most of the time and personally would use a prime lens as I sometimes have difficulty locating the bird when zoomed in so it is nice to zoom out and back in again.
Its a great lens although very large and heavy with no I.S and in no way hand holdable in any practical way.
I suppose a 500 mm with I.s would be nice to use handheld for birds in flight but have had some success with the Sigma.
If you are into primes then the 500 or 600mm are the ultimate I suppose.
I throw all my gear on a hand made trolley so I can carry it long distances.
Rick, Have a look at this website and he posts to Australia ( although the current exchange rate is a bit of a pain in the ... at the moment).
http://stores.ebay.com/montereypark
Samford Valley Qld.
Thanks for the link Reflex, some good glass at reasonable prices there. Will keep an eye on it.
200 f2 for 1900.00 caught my eye as well.
Thanks for the input people. As mentioned by Mark (miccro) in another post the large primes
come with there own set of challenges.
As mentioned I have been looking at the 500/4 but have lately been also thinking about
400/2.8 with 1.4 tc giving 560 but with the fexibility of returning to 400 if required.
Not much difference in price or weight though the 2.8 would be attractive.
Rick - if your considering 500mm f4 or 400mm 2.8 and solely shooting birds - the 500mm will win hands down. You will notice the difference in reach and you can add the 1.4 ex to it still- you will still want more reach sometimes. I really dont think you will need to drop back to 400mm often. the maximum magnification is similar as well (0.15x0.17) closest focusing distance. The biggest advantage with my 600mm is that i can shoot full frame sensors without extenders for most subjects - these lenses coupled to full frame with minimum cropping really are something else. I have a 1.6 crop body i still use with the 600mm for some subjects but on editing i really miss full frame.
mike
Not sure I understand that Mike?
Samford Valley Qld.
I use a canon 5dmk3 mainly on the 600 and with most subjects can achieve the photo I want without having to crop the image. I have sometimes left the 7d attached and shot similar subjects with similar framing - I am almost always disappointed with the file resolution in comparison, also the reduction in depth of field over the whole frame.
All I meant to say Is with the extra length the 500 brings, you may find you can use a full frame over a cropped sensor and improve the overall image quality.
Hope that makes more sense, I'm not brilliant at getting info across on forums
Sorry I was describing my 7d aps-c Sensor as having a 1.6x crop factor in relation to the "full frame" sensor size of the 5d
Rick
three years ago I made ths investment in big glass.
I bought the first series 500/4L IS over the first series 600/4L IS
1) 500 is 1.6kg lighter and focuses as close as 4.5m vs 5.5m (the MkII series 500/4 focuses down to 3.7m vs 4.5 and the lens is 3kg for the 500/4 vs 4kg
for the 600/4)
2) I shoot mostly birds of prey or larger waterbirds so no need for the extra 100mm focal length as my subjects tend to be bigger. For smaller birds I am happy to add the 2x converter as it produces very good rests if used with care and good field technique. While I often use the 1.4x converter I dont hqve problems with acquiring focus with my older 1D series bodies.
3) In the first version of these super teles from Canon the 500 kills the 600 for image quality. There's plenty of reports on that online. The 600 is no sluch thiugh of course.
4) I've used most 1D series bodies (except the 1Dx) and found the overall performance much better for the big lenses over cameras like the xxD series or the 5D MkII or MkIII.. the non-1D bodies don't seem to have the power to drive the big lens AF motors as well as the 1D bodies. I've missed more action shots with 5D bodies than 1D. Considering the used market is flooded with older 1D bodies they make good sense. The number of megapixels is not that big a deal for action photography. I've had double page spreads and as big as A2 exhibition prints done from 8-10 megapixel cameras. Sure more megapixels mean you can crop away more but that is not the answer to poor field technique.
4) I hand hold mostly and have no issues using the older and heavier 600/4L IS all day without a tripod I dont notice the weight of the 500/4 at all anymore.
5) the 500 is around 2k cheaper than the 600 too so for that I can take a couple of extra steps to get closer.
6) 400mm is not enough unless you're shooting from a hide
Thanks for your input Canonguy.
It is good to have info from people who actually have and use the lens.
I'm 99% on the 500/4 as by the sound of it will suit my shooting ie be able to hand hold
the majority of the time.
My body is D810 so I don't imagine there will be any problems with AF drive.
Thanks again to everyone for their thoughts.
Cheers
Sounds like you're a Nikon man.
be aware that (to the best of my knowledge) Nikon's 500/4VR does not take their 2x well.
Yes, had heard that, have a 1.4 so that should be ok.
Have not heard of too many telephotos the 2x does work well on though a friend has a 70 to 200
that he sometimes uses it with and gets some nice images, though he doesn't shoot many birds.
Too bad for Nikon sadly.
Most Canon superteles work well with a Canon 2x. I have the MkII 2x and have no problem even stacking it with my 1.4x on my 500mm when I am up and close to get some highly magnified shots....
Haha, not entering another forum chat about image quality regarding any of the super tele's but image quality is not a factor. I have shot all 3 and all out resolve both the 5d mk3 and 1ds bodies I've used them on. Both mk1 lenses are stunning and results are quite frankly down to technique and how you develope your shooting. The 500 is far easier to shoot with and the one I'd recommend, it will yield better results in most situations in light of this. ( you noticed I didn't recommend the 600). It has same max magnification at minimum focus distance. It's easier to travel with both packed in a rucksack and on planes. It really is the most versatile wildlife lens.
pure image quality there is nothing between the 500 and 600, in the studio photographing barcode a for days and pixel peeping , or in the field. The photos and quality will come with knowing how to use the equipment well.
i think rushing in and saying one super tele kills the other is a little enthusiastic.
i chose the 600 years ago, got a good one, it's bruised and battered and travelled all over the world. Until it brakes I'll not even consider parting with it, when it does I'm going straight to buy the new one. - the new 600 will probably replace the 500f4 and is already doing so with those who have tested.
I always thought the reports are likely individuals' opinions or pixel peepers. Albeit many comments were coming from Canon's own people here and many bird phktographers overseas always preferred the 500 . I have used a borrowed 600/4 MkI IS and got more than sharp shots myself. I agree a lot has to do with technique. My friend's struggling to take sharp shots with his 600/4 MkI IS and a 1D MkIV.
I will test them for him on the weekend as so far when I borrowed his 1DMkIV I had excellent images in the bag.
I know when I eventually upgrade super tele it will be the 600/4 MkII IS for the weight saving alone.