I'm looking for a budget telephoto lens and I'm wondering which of these two is the better option. They have very similar specs:
Tamron AF 70-300mm f/4.0-5.6 Di LD Macro Zoom Lens for Canon Digital SLR Cameras
Sigma 70-300mm f/4-5.6 DG Macro Telephoto Zoom Lens for Canon SLR Cameras
This is for my Canon EOS XTi. Thank you!