Sigma 500/4.5 HSM or Nikkor AF-I 300/2.8+TC20E to replace AIS 600/5.6?

Hi friends....

Another technical question...

I've an AIS 600/5.6 lens. I missed many opportunities of taking

pictures

because this is a manual focus. So I would like to replace this with

an auto focus..

I'm thinking about two options

1) Sigma 500mm/4.5 HSM(Silent wave)

2) AF-I Nikkor 300/2.8 + TC20E

The used price for both are around 2500, which is my budget...

This is what I know about these two

1) Sigma 500mm/4.5 HSM

It's very quiet and fast auto focus. Color is also excellent.

It lacks some contrast comparing to Nikkor lenses..

2) AF-I Nikkor 300/2.8 + TC20E

This lens itself is amazingly sharp as it has photodo rating of

4.2 with score of 81 at f/2.8.

I've seen many threads about AF-I 300 and TC20E. I found you will

lose AF speed and little bit of sharpness with this combo.

This is my question..

Which is better in

1) Sharpness

2) Auto focus speed

3) Contrast??

Thanks in advance�

Sorry no one has answered your question until now. Let me take a crack at it.<P>

First of all, since you are getting rid of the 600/5.6 because it is manual focus, if the combo you replace it with focuses too slowly, you're not likely to be very happy. That said, I might suggest a few things: 1) loss of contrast is not a good thing in this case and will, for all intents and purposes, appear to be "less sharp"; 2) all things being equal (which, anyway, they are not) you want to stay with the Nikkor glass in most cases - the Sigma as described will likely be inferior to the lens you have now; 3) the combination of 300/2.8 Nikkor and 2X converter will definitely be inferior to the 600/5.6 Nikkor. Rather than trying to throw technology and not-enough money at this problem, might it not be better to do more shooting and work to enhance your skills, so that you miss fewer shots?

Doug,

Thanks a lot. So far you are the only person responded!!!

Yeah, you are right. I'm also coming to that. I realized that photographer's ability has a lot to do with the pic. I'm going to try White tailed deer with this in Wisconson this winter and will decide after that. Anyway thaks again for your answer..

Cheers.

Jemini,<P>

You're welcome. FWIW, I think you're making a good decision. Since you're into nature photography, here is some <a href=http://www.wildlightphoto.com/>inspiration</a>. These were shot with a combination of Leica and Nikon glass - all of it manual focus. Hope to see your new efforts posted here before too long.<P>

Cheers,