For starters I am no expert at testing lens so if l have overlooked some aspect of this exercise then I apologize.
The reason I compared my all in one tamron 18-270 zoom with my tamron 70-200 f2.8 was to see just how close could it come to the fast lens.
I have seen in reviews of the fast tamron (70-200) the IQ up there with the big name lens, for this exercise I took a pictures at 70mm and 200mm at f11 on both lens, I have also included a shot at 270mm just out of curiosity.
On my next post I have to pictures shot at 200mm f11 and crop the image to compare both lens.
The image below is from my tamron 70-200 at 70mm f11
This image below is from my tamron super zoom 18-270 at 70mm f11
Then the shots were taken zoom in at 200mm for both lens
The image below was from my tamron 70-200 at 200mm f11
The image below was from the super zoom 18-270 at 200mm f11
And this final shot was shot at 270mm just see if it really went too soft at the end of its focal length
The other reason this was done was because of some questions l saw on the forum people rightfully being concerned how this lens performed before out laying big sums of money.
I opinions would help future buyers of the lens making up their minds whether to buy or not buy.
I am not recommending it or saying avoid it but this is just my results, but since I took the effort write this up I may as well voice my opinion ;-)
Personally I love this lens and it also works fine with my Kenko teleconverter without much trouble out doors. If anyone is curious on how the images come out with the teleconverter just ask for samples to be posted up.