Visit MPB Visit MPB Visit MPB

Pentax Forums reviews the Sigma Art 18-35mm

jules
Posted 03/11/2014 - 08:17 Link
Cheers Jules...

My viewfinder is 576,000,000 pixels.
My other viewfinder is 5.76,000,000.

www.exaggeratedperspectives.com
alfpics
Posted 03/11/2014 - 08:50 Link
Interesting how it gets slated for poor AF performance; but could that not be down to the camera AF sensor not able to work well with such a wide aperture as the DOF is too low? Pentax make the point that some of the sensors can cope with f2.8 for example and so is 1.8 (and 1.4 for the other art lens) too open?
Andy
jules
Posted 03/11/2014 - 15:02 Link
Don't know really, Andy?
I read somewhere that Pentax use F2 sensors but just rate them as better than 2.8, no idea where though! What strikes me about the review is not really how good the Sigma is, as it's fantastic in all areas except the focus thing, it is a very very bright zoom lens, so it may be affecting the K3 Af? It's how well the 20-40 Ltd did against it and just how bad the DA* 16-50 is? The 16-50mm performance actually came as no suprise to me as I have had two of those previously and decided to bail on that un permanently but the 20-40 has now piqued my interest...
Cheers Jules...

My viewfinder is 576,000,000 pixels.
My other viewfinder is 5.76,000,000.

www.exaggeratedperspectives.com
Algernon
Posted 03/11/2014 - 17:40 Link
jules wrote:
Don't know really, Andy?
I read somewhere that Pentax use F2 sensors but just rate them as better than 2.8, no idea where though! ...............

You shouldn't be reading nonsense like that Jules

Have you seen the Digitalis test on the US forum?
Doesn't impress me

--
Half Man... Half Pentax ... Half Cucumber

Pentax K-1 + K-5 and some other stuff

Algi
alfpics
Posted 03/11/2014 - 17:48 Link
Algernon wrote:
jules wrote:
Don't know really, Andy?
I read somewhere that Pentax use F2 sensors but just rate them as better than 2.8, no idea where though! ...............

You shouldn't be reading nonsense like that Jules

Have you seen the Digitalis test on the US forum?
Doesn't impress me

--

Digitalis??
Andy
Algernon
Posted 03/11/2014 - 18:02 Link
Try ....... link

--
Half Man... Half Pentax ... Half Cucumber

Pentax K-1 + K-5 and some other stuff

Algi
jules
Posted 03/11/2014 - 18:09 Link
Algernon wrote:
jules wrote:
Don't know really, Andy?
I read somewhere that Pentax use F2 sensors but just rate them as better than 2.8, no idea where though! ...............

You shouldn't be reading nonsense like that Jules

Have you seen the Digitalis test on the US forum?
Doesn't impress me

--

Nope first review of a lens that I have absolutely no interest in, got a link Algi? It's way to big and fat to make it to my bag
Cheers Jules...

My viewfinder is 576,000,000 pixels.
My other viewfinder is 5.76,000,000.

www.exaggeratedperspectives.com
Edited by jules: 03/11/2014 - 18:10
Smeggypants
Posted 03/11/2014 - 18:30 Link
alfpics wrote:
Interesting how it gets slated for poor AF performance; but could that not be down to the camera AF sensor not able to work well with such a wide aperture as the DOF is too low? Pentax make the point that some of the sensors can cope with f2.8 for example and so is 1.8 (and 1.4 for the other art lens) too open?

I have a Pentax A50 f/1.2 and it's worked great at 1.2 with all the Pentax DSLRs I've owned... K10D, K20D, K-5 ( three of them ) and K-5IIs
[i]Bodies: 1x K-5IIs, 2x K-5, Sony TX-5, Nokia 808
Lenses: Pentax DA 10-17mm ED(IF) Fish Eye, Pentax DA 14mm f/2.8, Sigma 17-70mm f/2.8, Pentax-A 28mm f/2.8, Sigma 30mm F1.4 EX DC, Pentax-A 50mm f/1.2, Pentax-A 50mm f/1.4, Pentax-FA 50mm f/1.4, Pentax-A 50mm f/1.7, Pentax DA* 50-135mm f/2.8, Sigma 135-400mm APO DG, and more ..
Flash: AF-540FGZ, Vivitar 283
alfpics
Posted 03/11/2014 - 18:46 Link
Smeggypants wrote:
alfpics wrote:
Interesting how it gets slated for poor AF performance; but could that not be down to the camera AF sensor not able to work well with such a wide aperture as the DOF is too low? Pentax make the point that some of the sensors can cope with f2.8 for example and so is 1.8 (and 1.4 for the other art lens) too open?

I have a Pentax A50 f/1.2 and it's worked great at 1.2 with all the Pentax DSLRs I've owned... K10D, K20D, K-5 ( three of them ) and K-5IIs

Well that blows that theory out of the water then!
Andy
alfpics
Posted 03/11/2014 - 18:47 Link
Algernon wrote:
Try ....... link

--

Thanks Algi
Andy
jules
Posted 03/11/2014 - 20:43 Link
Cheers Jules...

My viewfinder is 576,000,000 pixels.
My other viewfinder is 5.76,000,000.

www.exaggeratedperspectives.com
screwdriver222
Posted 03/11/2014 - 20:56 Link
Quote:
I have a Pentax A50 f/1.2 and it's worked great at 1.2 with all the Pentax DSLRs I've owned... K10D, K20D, K-5 ( three of them ) and K-5IIs

Did it auto focus?

Jeff
Blythman
Posted 03/11/2014 - 21:07 Link
Well, this was very much on my wanted list. Its not anymore, for now. Hopefully AF will improve
Alan


PPG
Flickr
Algernon
Posted 03/11/2014 - 21:15 Link
screwdriver222 wrote:
Quote:
I have a Pentax A50 f/1.2 and it's worked great at 1.2 with all the Pentax DSLRs I've owned... K10D, K20D, K-5 ( three of them ) and K-5IIs

Did it auto focus?

Jeff

It came with a FREE 30 Metre Tape!

--
Half Man... Half Pentax ... Half Cucumber

Pentax K-1 + K-5 and some other stuff

Algi
cb95amc
Posted 03/11/2014 - 21:35 Link
The way I read the AF issue, it's also something Nikon and Canon owners have been experiencing, and it seems to only be present with Phase AF.
Hopefully they can fix it via a firmware update, as that issue aside it sounds like a damn fine lens.
Pentax K-30
DA 18-135 WR, DA 18-55 WR, DA 55-300, FA 35-80
Chinon 50mm 1.7, RMC Tokina 28mm 2.8
32GB Toshiba FlashAir

Add Comment

To leave a comment - Log in to Pentax User or create a new account.