Tamron NEW 18-200 image quality test

troglodite

OK - I'm no proffessional lens tester but these are my results. All images here taken of a brick wall roughly 7 feet away, on a tripod, with a remote release with a mirror lockup for maximum sharpness. Canon 350D/Rebel XT 8mp and a nice heavy Bogen tripod.

My mistake is that it was a bit overcast but I had the white balance on daylight so... but I did this to inspect the sharpness and overall quality. I can still return/exchange it for another 20 days or so I wanted to see how it did.

Any input would be nice, I did this for myself but figure I wouls share my results.

Here we go!
I hope this helps!

limbik

The 1/3 and 1/4 shots look unusually blurry for such small apertures. At 4.5 and 5.6 it looks great, that is a good sign for the lens at least so far.

Scott_Quier

You don't indicate if these are center crops or corner. Even so, it appears the lens is really only useful between f/4.0 and about f/8.0. Larger aperature, it gets real soft. Smaller, it appears to suffer from diffraction issues. Even in it's "sweet" spot, it still seems a tad soft. I'm thinking I would be hugely dis-satisfied with this one.

troglodite

Scott_Quier wrote:

You don't indicate if these are center crops or corner. Even so, it appears the lens is really only useful between f/4.0 and about f/8.0. Larger aperature, it gets real soft. Smaller, it appears to suffer from diffraction issues. Even in it's "sweet" spot, it still seems a tad soft. I'm thinking I would be hugely dis-satisfied with this one.

thanks for the evaluation

these are all center crop - same center spot for all images
my other option was a 75-300 IS canon, but I was told the tamron should have a better lens than the canon entry level, would that be true?

cmason

troglodite wrote:

my other option was a 75-300 IS canon, but I was told the tamron should have a better lens than the canon entry level, would that be true?

Not that I have heard for the 70-300 IS model. For the standard 70-300 lens, it is likely to be so.

troglodite

Ok, that's it. I'm returning it... maybe someday they'll be able to make a decent lens with that type of a range.

Anyone know of any lens review sites where they do the kind of image test like I have above (or better =])?

Jeffro

troglodite wrote:

Ok, that's it. I'm returning it... maybe someday they'll be able to make a decent lens with that type of a range.

Anyone know of any lens review sites where they do the kind of image test like I have above (or better =])?

Before you jump to conclusions why not try it again. I'm guessing you used auto focus? It doesn't look like the focus was spot on, which can happen when there isn't a lot of contrast in a scene. I believe digital uses the contrast in a scene to focus. Try it in manual one, or pick something with a bit more contrast. All the shots look OOF to me, I can't believe the lens is that bad. I could be wrong.

troglodite

Hmmm.... good suggestion. I'll try and find something else.

My eyesight sucks so I have to rely on autofocus :cry

I'll try a few shot's again tomorrow and see if it was just me.

cmason

troglodite wrote:

Anyone know of any lens review sites where they do the kind of image test like I have above (or better =])?

http://www.the-digital-picture.com/Reviews/
http://www.photozone.de/8Reviews/index.html
http://www.pbase.com/lightrules/lenstests
http://www.bobatkins.com/photography/reviews/index.html

claudermilk

Don't forget http://www.photodo.com now that they're alive again.

troglodite

new results
New images, this time further away and with a higher contrast subject. ISO 200 - heavy tripod, wire release. Roughly about 15' away.

This to me doesn't look too bad, a bit soft at small ap's.

troglodite

o crap! i just realized I labeled this 18-300 not 18-200... i'm such a noobert!

Manfr3d

troglodite wrote:

o crap! i just realized I labeled this 18-300 not 18-200... i'm such a noobert!

200mm @ f32 and f40? Or is that a mistype?
It would anyway have little or no use to test
it there because of diffaction as someone
mentioned above.

troglodite

That was the reading on the camera - the ap changes when you go from 18mm to 200mm by a couple stops.

I retook the test because I thought it was out of focus, which someone else had mentioned.

Well guys, should I keep it or huck it?

limbik

troglodite wrote:

Well guys, should I keep it or huck it?

Take a few casual walk around shots with it outdoors. I'd like to see what kind of pictures this thing can take and putting it to real use ought to let you know one way or another if its worth it for you to keep.