03-14-2011, 11:44 AM
[quote name='Lampo' timestamp='1300102110' post='6739']
Currently I am planning an update for my standard lens for my Pentax K-5. As the Pentax DA* 16-50 is too expensive for me at this point and because the reviews of this lens are not that positive, I am looking at alternatives. Due to my limited budget, I have come up with two alternatives:
1. Tamron 17-50 2.8 non-VC (old version) €314
Pro's: - 17 mm wide
- Corner resolution is pretty good, even at f2.8
- Very positive reviews here and elsewhere
Con's: - Build quality
- AF noise
- Quality control issues
2. Sigma 18-50 2.8 EX DC Macro €349
Pro's: - I expect better build quality than the Tamron
- AF is supposedly much more quiet than the Tamron
Con's: - 18 mm wide, but actually -according to some reviews- it is close to 19 mm in real life
- Resolution of the borders at large apertures is dissapointing, need to stop down to f5.6
I just have difficulty to choose between these lenses. My reason to buy this lens is low light photography and portraits and off course IQ. I have to say that I really appreciate good built quality and that I do not mind AF noise, but it is nice if the noise is not too disturbing. Another question I would like to ask is how I can test these lenses in the shops for decentering or other QC issues. I mean they do not have a brick wall inside and most of the shops here in the Netherlands are situated in industry parks where it is very hard to find a brick wall in the first place. I was planning on taking a newspaper with me to test if the focus accuracy is decent.
Thanks for all your help!
[/quote]
Is it possible for you to try both lenses yourself?
People who have tried them side by side uniformly say that the Sigma is their favorite. A bit more contrasty, less CA wide open, and sharpness is not a let down for that Sigma.
About the AF noise, I know that for the Canon mount both lenses have motors inside the lens, and that there the Sigma is better (both noise wise and speed wise). And is more accurate. But I do not know if that is the same on Pentax... do they have their own motor for Pentax, or do they use the in-body motor (as I have always thought they are)?
If they use the in-body motor, I think the Sigma and Tamron will not show the difference you see for the Canon mount.
The Sigma is better built too, and it offers a closer MFD.
Currently I am planning an update for my standard lens for my Pentax K-5. As the Pentax DA* 16-50 is too expensive for me at this point and because the reviews of this lens are not that positive, I am looking at alternatives. Due to my limited budget, I have come up with two alternatives:
1. Tamron 17-50 2.8 non-VC (old version) €314
Pro's: - 17 mm wide
- Corner resolution is pretty good, even at f2.8
- Very positive reviews here and elsewhere
Con's: - Build quality
- AF noise
- Quality control issues
2. Sigma 18-50 2.8 EX DC Macro €349
Pro's: - I expect better build quality than the Tamron
- AF is supposedly much more quiet than the Tamron
Con's: - 18 mm wide, but actually -according to some reviews- it is close to 19 mm in real life
- Resolution of the borders at large apertures is dissapointing, need to stop down to f5.6
I just have difficulty to choose between these lenses. My reason to buy this lens is low light photography and portraits and off course IQ. I have to say that I really appreciate good built quality and that I do not mind AF noise, but it is nice if the noise is not too disturbing. Another question I would like to ask is how I can test these lenses in the shops for decentering or other QC issues. I mean they do not have a brick wall inside and most of the shops here in the Netherlands are situated in industry parks where it is very hard to find a brick wall in the first place. I was planning on taking a newspaper with me to test if the focus accuracy is decent.
Thanks for all your help!
[/quote]
Is it possible for you to try both lenses yourself?
People who have tried them side by side uniformly say that the Sigma is their favorite. A bit more contrasty, less CA wide open, and sharpness is not a let down for that Sigma.
About the AF noise, I know that for the Canon mount both lenses have motors inside the lens, and that there the Sigma is better (both noise wise and speed wise). And is more accurate. But I do not know if that is the same on Pentax... do they have their own motor for Pentax, or do they use the in-body motor (as I have always thought they are)?
If they use the in-body motor, I think the Sigma and Tamron will not show the difference you see for the Canon mount.
The Sigma is better built too, and it offers a closer MFD.