New to the forum, help me choose a lens

[Shooter Tiff]

Hello, I just joined up and have some questions on telephoto lenses for a Pentax K10D I picked up a month ago.

Right now I only have an 18-35mm the camera is great, but I need zoom.
70-300 is what I want, and it needs to be less than 6" long.

Outdoor sports & nature are my usual shooting conditions. Macro capability is important to me too.
I would like to spend less than $500
Here's a few lenses I have been looking at:

Tamron AF70-300mm F/4-5.6 Di LD Macro 1:2
http://www.tamron.com/lenses/prod/70300_di_a017.asp

Sigma 70-300mm F4-5.6 DG MACRO
http://www.sigmaphoto.com/lenses/len...04&navigator=3

Sigma 70-300mm F4-5.6 APO DG MACRO
http://www.sigmaphoto.com/lenses/len...03&navigator=3

Will the Sigmas work on my K10D?
what is the difference between the two Sigmas?

are there better options:idea: Are these all crap?


Thanks for the help!

[Frog]

I have the sigma with the apo. APO is made with low dispersion glass and minimizes color aberations. Costs a bit more but I think its worth it.
Yes, they make them for Pentax cameras. The only thing I don't like about mine is that its noiser than my other zoom lens but I might have been spoiled by how quiet my other is.
Here's this sites reviews of the sigma with apo http://www.photographyreview.com/cat...0_3128crx.aspx

Site reviews for the Tamron. http://www.photographyreview.com/cat...9_3128crx.aspx

I didn't see reviews for the sigma without apo. Also if you search you'll find many of the reviews are with that lens on specific brands but didn't see any for Pentax so just put the generic reviews links.

The sigma with apo has better reviews and if you shop you can get them fairly inexpensivly.

[rovowen]

I took this photo with the Tamron 70-300. As it was getting dark and I should have
used a higher ISO instead of 400.
But was able to work a little in PP and got this out of it.

Just to let you know, my PP is not the best.
This lens can take some good shots, but when you zoom it, at the very least you will have to have a mono-pod.

[freygr]

I have the 35mm film version of this lens: Tamron AF70-300mm F/4-5.6 Di LD Macro 1:2
http://www.tamron.com/lenses/prod/70300_di_a017.asp
and I'm very happy with it. I been told by some the the Tamron 70-300 was not sharp but the one I have is. Remember that long lenses have very little DOF.