Tamron 18-250mm Di II Lens Review – The Ultimate Ultra Zoom Lens For DSLRs

The Tamron AF18-250mm F/3.5-6.3 Di II LD Aspherical (IF) gives DSLR users what the normal ultra zoom did for the SLR. As any DSLR user knows that lenses they use have a magnification making it hard to get the wide angle many users love. The body I happen to test it on was a Nikon Mount with a 1.5 magnification. That means I had a 27-375mm zoom in 35mm film equivalent. That’s your wide angle all the way to nearly 400mm! This lens has almost a 14x (13.9 but close) which is the industry’s largest zoom range.

The Di II series lenses were designed for DSLRs so make sure you don’t accidently buy this for a film camera. The lens is not design for cameras with image sensors bigger then 24mm x 16mm. This lens comes in a Canon, Nikon, Pentax, and Sony mount.

This overall is the best do everything lens. It can let you take a nice picture of the wide ocean scene at 18mm and then a nice close-up of a boat you didn’t even notice with the 250mm zoom. All this is doable without having to even move. Just twist the len a bit and hold the camera steady.

For a lens with such a long zoom it’s very small in size. Tamron is known for making their lenses very compact. This lens is an F/3.5-6.3 16 element lens in 13 groups. There are 7 aperture blades. It has a minimum focus distance of 17.7 inches which means it has a magnification ratio of 1:3.5. It is about 2.9 by 3.3 inches when at the 18mm mark and weights about 430 grams. It can take 63 non rotating filters. It also comes with a snap-on petal hood. The exchange for the compact size comes with the f/6.4 at the 250mm end which is above the normal F/5.6. The smallest aperture is F/22.

The case itself is made of plastic except for the metal mount. The zoom ring is rubber. It has two inner lens tubes so the lens extends pretty far out. It has a zoom lock so at the 18mm mark.

The autofocus speed is decently fast. It takes about a second for the focus to go from infinity to the minimum.

You might notice some distortion at the end of the lens of course. It has a little distortion but since this is a consumer lens and has such a long zoom range you usually wont use it all the way at the extreme and if you do you likely wont care or notice it. Compared to other ultra zooms this does well for distortion.  

For such an extreme lens it doesn't have many problems. This Tamron 18-250 lens doesn’t suffer from that many issues being the largest   zoom range consumer lens. You get problems like any ultra zoom at the ends of the zooms but on this lens it’s not significant.   You likely want to use this lens with a tripod or a camera with built-in image stabilization like Sony or Pentax. Tamron makes this lens in the Canon, Nikon, Pentax, and Sony Mount.

If you’re a DSLR user looking for one lens and only one lens, this is it. It lets you shoot everything from wide angle to super ultra telephoto. It doesn’t have any poor qualities. It has average focus time and distortion which is good for such an extreme lens. This lens is only missing image stabilization however if your shooting ultra zoom your going to need a tripod anyways. Those who want a good do it all lens and want to save on the image stabilization this is for you.

The Tamron 18-250mm Di II lens has won the EISA Best Product Award for 07-08. It was also selected by American Photo as an editor’s choice. This lens comes with a nice six year warranty.  

The lens has a $699.95 retail price and a street price of $450-500 (Sept 07). Find more about the Tamron AF18-250mm F/3.5-6.3 Di II LD Aspherical (IF) lens from www.tamron.com.

Model	A018
Lens Construction (Groups/Elements)	13/16
Angle of View	Diagonal 75°33'-6°23'
	Horizontal 65°36'-5°19'
	Vertical 46°21'-3°19'
Diaphragm Blade Number	7
Minimum Aperture	F/22
Minimum Focus Distance	17.7in.(0.45m)
Macro Magnification Ratio	1:3.5 (at f=250mm MFD 0.45m)
Filter Diameter	ø62
Weight	430g (15.2oz)
Diameter x Length	ø2.9 x 3.3in.
	(ø74.4 x 84.3mm)
Accessory	Flower shaped lens hood
Mount	Canon, Nikon, Pentax, Sony