Tamron Closeup
After some more experimentation with my Tamron 28-300 Di VC, I think I finally understand what this lens is and what to do with it. It is a closeup lens, not a telephoto lens. That is, it takes really good pictures fairly close (within a few meters) and pretty crappy ones far away. For example look at this nice close-up of a juvenile American coot taken at 300mm:
Santee Lakes, San Diego County, 2009-08-23
1/800 s, f/6.3, ISO 400, handheld
It’s pretty good, especially around the body where you can easily make out the individual feathers. In fact, if anything, it’s over-sharp; though that’s probably just a combination of me over-sharpening it in Lightroom and the JPEG conversion. The original full-size photo is even better than this.
Now compare to this shot of a far-away coot taken with the same lens. You’d expect the subject to be smaller, but it’ worse than that: very, very fuzzy and unsharp, even with a much faster shutter speed:
1/5000 s, f/6.3, ISO 400, handheld
Going back through my photographs with this lens, I notice this with a number of subjects: within a few meters I get great shots. Far away, I might as well not bother.
The 300mm extension just lets fill more of the frame with close subjects. It doesn’t really help bring far away birds much closer. Maybe this is just how the optics are designed, or is what the VC (image stabilization) and auto-focus are optimized for?
So what does one shoot with a 300mm closeup lens? I suspect the answer is bird feeders and wasps. It’s good for anywhere you can get reasonably close to your subject, but not right on top of it like you can with a real macro lens. In the meantime, I’m still looking for a good telephoto lens for birds.
Update: after running some tests in my living room:
Below 50mm this lens is too fuzzy.
At 50mm, f/5.6 seems best
At 77mm, f/7.1 is sharpest
At 100mm, f/8 is sharpest
At 135mm, f/7.1 is sharpest
At 200mm and 300mm, f/8 (or higher–I didn’t test) is sharpest
September 20th, 2009 at 5:50 PM
Without spending very large sums of money on, say a 500mm autofocus with 1.2x or 1.5x converter (I’ve seen excellent results from birders using Canon kit, I think that your results from this lens are typical. I think that expecting pin sharp results at the full 300mm range from a lens which has to go from 28mm wide-angle to 300mm telephoto is probably not realistic. What I would say is that I would not expect pin-sharp at 300mm without very careful focussing, and using a tripod. I think you’ve done well to get this result with a hand-held camera, probably because you shot at 1/5000th.
I have attempted long-distance photography using a Tokina 500mm catadioptric (mirror) lens, using a tripod, and even with that I find it very difficult to focus sufficiently precisely to resolve all of the detail that I would like to see. I have a Nikon D40, 18-55mm DX, 55-200mm DX autofocus lenses, but all my other lenses can only be used on manual settings, which is a pain.
Take a look at photos uploaded to http://www.birdguides.com where camera, lens and shooting information is often given, to get a sense of what is possible.
Good luck.
September 21st, 2009 at 12:06 PM
Reg is right on. Superzooms are not known for their long-end performance; something has to give in that large of a range, and in this case it’s the long end. Still, that 300mm looks pretty bad. My Pentax 18-250 is far better on the long end. There’s some serious purple-fringing going on (you could try shooting in less harsh light to alleviate that).
At the end of the day, you *migh* see better results by replacing this lens with a better copy, but really that’s only going to get you so far. If you want consistently better results, go buy a “Bigma” (Sigma 50-500) or a Canon 100-400L or any number of higher end lenses. It will be worth the money in the long run.
September 21st, 2009 at 12:20 PM
BTW, you can rent lenses before trying them — one of the benefits of shooting Canon (or Nikon). Here’s a link to a a place that rents the 100-400L:
http://www.lensrentals.com/rent/canon-100-400mm-f4.5-5.6-l-is/for-canon