[Crepusculum]

I'm new to Pentax, I'm planning on picking up a K7 soon. I have used Sigmas in the past, more recently a 150-500 on my Nikon D700. I was wondering if anyone was able to tell me which is the preferred 18-250 lens, the Pentax or the Sigma.

Thanks!

[WMBP]

I'm new to Pentax, I'm planning on picking up a K7 soon. I have used Sigmas in the past, more recently a 150-500 on my Nikon D700. I was wondering if anyone was able to tell me which is the preferred 18-250 lens, the Pentax or the Sigma.

I've used both the Tamron 18-250 and the Pentax 18-250, which folks in the know here say is the same lens as the Tamron, just rebranded. Both are really quite good lenses - better than they have a right to be, given the extraordinary range of the zoom.

I haven't used the Sigma but the reviews I've read make it look very good, too, perhaps even better. I recently purchased the Pentax 18-250 (well, a couple of months ago) and I didn't consider the Sigma at all; wish I had. The reviews for the Sigma at Amazon.com are as good (4.5 stars out of 5) as the Pentax. Oddly, the Tamron is rated slightly lower (4 stars) although it's supposed to be identical to the Pentax branded lens. Unfortunately there are no reviews of the Sigma over at bhphoto.com or adorama.com.

If you do decide to buy the Sigma, consider buying it from sigma4less.com. Their price ($499) is $30 lower than Amazon's right now.

Will

[causey]

Pentax (or Tamron) 18-250mm, then get DxO Pro from www.dxolabs.com, and you'll have superior output from 18 to 250. Check out this thread. (DxO doesn't have a module for Sigma 18-250mm.) It's amazing what this piece of software can do to improve the sharpness of your pics.

[audiobomber]

I'm new to Pentax, I'm planning on picking up a K7 soon. I have used Sigmas in the past, more recently a 150-500 on my Nikon D700. I was wondering if anyone was able to tell me which is the preferred 18-250 lens, the Pentax or the Sigma.

Thanks!

From the reviews I've read they're neck and neck.

The Pentax 18-250 has weaknesses that are very predictable. Watch out for barrel distortion at 18mm, stop it down to F8 when shooting at the wide end and the long end, and it will perform exceptionally well. Note that the K-7 contains software to correct distortion, CA and vignetting with the Pentax lens, but not the Sigma.

[Jasvox]

Lots of older threads on the board about these lenses and direct comparisons...most seem to be in favor of the Pentax/Tamron versions than the Sigma. I bought the Tamron version about 2 years ago and have been very pleased with mine.

Jason

[tr13]

I made few test with Focal Magic deconvolution algorithm with lenses that are slightly soft.
And according to them, is you don't plan to print posters result will be identical to sharper lens.
Free RawTherapee have similar algorithm for raw images.

[EsBee]

I recently got the Pentax 18-250mm and I think it makes an excellent all-round lens. It really shines between 28mm and 200mm even wide open, with better than acceptable results at both ends. My only issue is with zoom creep but the lens does allow you to lock it at 18mm.

One good thing about such zooms is a lot of people start off with them and move onto primies so it is not difficult to find one for a good price if you are patient.

No experience or knowledge about Tamron or Sigma brands though from what I'v read the only difference between the Tamron and Pentax seems to be in the lens coating.