Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
12-20-2023, 10:37 PM   #1
Site Supporter
Site Supporter




Join Date: May 2023
Location: Quebec
Posts: 48
Sigma 18-35 F1.8 Art with K-3 III Live view AF?

Hello!

I am looking for some first hand experience with this combo.Does anyone use the Sigma 18-35 F1,8 Art with the K-3 III specifically?Thanks a lot.

12-20-2023, 10:52 PM   #2
Loyal Site Supporter
Loyal Site Supporter
UncleVanya's Avatar

Join Date: Jul 2014
Photos: Gallery | Albums
Posts: 28,347
That lens has a checkered history with focusing. The issues go beyond Pentax. Iím unclear if the k3iii improved things but previously that lens seemed to be a variable experience. So people had good results - others, despite trying multiple copies - found it impossible to get reliable auto focusing.
12-21-2023, 01:29 AM - 1 Like   #3
Site Supporter
Site Supporter
Hattifnatt's Avatar

Join Date: Mar 2013
Location: Bucharest
Photos: Gallery
Posts: 4,622
Somebody please correct me if I'm wrong, but focusing using live view AF will be always correct even if the lens has focus problems like FF/BF. In liveview, camera will be using contrast AF (using the image on the sensor to pick the focus position with maximum contrast) as opposed to phase AF using the viewfinder. So the focus will always be correct even if the lens is not calibrated, although it will be slower. That's the reason I use liveview AF with my K-1 and Sigma 35mm Art, which also has focus problems.
12-21-2023, 01:37 AM   #4
Pentaxian
Medex's Avatar

Join Date: May 2013
Location: Vilnius
Posts: 1,019
QuoteOriginally posted by Hattifnatt Quote
Somebody please correct me if I'm wrong, but focusing using live view AF will be always correct even if the lens has focus problems like FF/BF. In liveview, camera will be using contrast AF (using the image on the sensor to pick the focus position with maximum contrast) as opposed to phase AF using the viewfinder. So the focus will always be correct even if the lens is not calibrated, although it will be slower. That's the reason I use liveview AF with my K-1 and Sigma 35mm Art, which also has focus problems.
Unfortunately sometimes Live View AF (CDAF) does not work correctly, e.g. K-5/5II with KAF4 lenses like DFA*50/1,4 or DFA*85/1,4. PDAF works correctly.
Theoretically Sigma 18-35 Art should work correctly with K-3III in Live View mode

12-21-2023, 03:48 AM   #5
Site Supporter
Site Supporter




Join Date: May 2023
Location: Quebec
Posts: 48
Original Poster
QuoteOriginally posted by Medex Quote
Unfortunately sometimes Live View AF (CDAF) does not work correctly, e.g. K-5/5II with KAF4 lenses like DFA*50/1,4 or DFA*85/1,4. PDAF works correctly.
Theoretically Sigma 18-35 Art should work correctly with K-3III in Live View mode
Thanks.

Yes,theorically the Sigma 18-35 1.8 + K-3 III should work well but we never know for sure.This is why i look for first hand experience with this combo.
12-21-2023, 05:31 AM - 1 Like   #6
Senior Member
Password1234's Avatar

Join Date: Apr 2017
Location: Montreal
Photos: Gallery
Posts: 143
Hi, I don't remember having any focus issue using live view with this combo, I remember the weight of holding both using live view though. Remember that there is still some lag between the pressing of the shutter and the actual picture using the mechanical shutter, I never tried with electronic shutter but does it prevents this ? The AF issues using the af module using the viewfinder on k3iii can happen on certain artificial light, I had no particular issue in sunlight, not 100% perfect but good.
12-21-2023, 05:34 AM   #7
Site Supporter
Site Supporter




Join Date: May 2023
Location: Quebec
Posts: 48
Original Poster
QuoteOriginally posted by Password1234 Quote
Hi, I don't remember having any focus issue using live view with this combo, I remember the weight of holding both using live view though. Remember that there is still some lag between the pressing of the shutter and the actual picture using the mechanical shutter, I never tried with electronic shutter but does it prevents this ? The AF issues using the af module using the viewfinder on k3iii can happen on certain artificial light, I had no particular issue in sunlight, not 100% perfect but good.
Thanks a lot!

12-21-2023, 05:37 AM - 2 Likes   #8
Senior Member
Password1234's Avatar

Join Date: Apr 2017
Location: Montreal
Photos: Gallery
Posts: 143
Ok, I just tried using electronic shutter, no lag, face detection activated as soon as a face got in the frame, tack sharp a 1.8
I never thought of using electronic shutter using live you because I'm used to using flash but I'll remember that next time.
But still, I have the grip and this combo is big and heavy for live view for me, but it works.
12-21-2023, 05:54 AM   #9
Site Supporter
Site Supporter




Join Date: May 2023
Location: Quebec
Posts: 48
Original Poster
QuoteOriginally posted by Password1234 Quote
Ok, I just tried using electronic shutter, no lag, face detection activated as soon as a face got in the frame, tack sharp a 1.8
I never thought of using electronic shutter using live you because I'm used to using flash but I'll remember that next time.
But still, I have the grip and this combo is big and heavy for live view for me, but it works.
Yes i have the grip too and it's a heavy combo for LV but i am accustomed to use it with a few heavy lenses now.
Thank you so much for all the testing.It helps a lot!
12-21-2023, 10:41 AM - 1 Like   #10
Loyal Site Supporter
Loyal Site Supporter
AlwaysAl's Avatar

Join Date: Mar 2007
Location: West GTA, Ontario, Canada
Photos: Gallery | Albums
Posts: 549
Originally purchased this lens as a replacement to my Tamron 17-50 mostly to accommodate full-length portraiture. As an aside, I had been disappointed with the Tamron, everything about it seemed second rate compared to the Tamron 28-75 which had been my go-to lens for many prior years. The Sigma ART seemed to offer a solution and, although pricey ( I was an early adopter), it was everything it claimed (and far better quality than some of the Sigma lenses I had previously owned). The Sigma had a steep learning curve but rapidly became one of my favourite lenses on the APS-C bodies. Any focusing issues I experienced could be attributed to my mistakes. The technology of the K-3 III bought a new life to all of my lenses (in varying degrees) but none as much as the perceived performance of the 18-35. When testing focus (with the myriad of poor focus related comments in my mind) I thought I had finally experience a manifestation of this phenomena. The reality was the lens/camera combination was focusing so quickly and silently (I'm a little deaf) I'd missed the correction as compared to that experienced with previous APS-C bodies. This lens, and the DA*50-135, have become my walk-around lenses. What's perhaps the worst thing with this pair; no WR but then neither am I.

https://www.pentaxforums.com/forums/members/1711-alwaysal/albums/3052-when-m...ture136172.jpg

Last edited by AlwaysAl; 12-21-2023 at 10:45 AM. Reason: original image didn't appear
12-21-2023, 02:57 PM - 1 Like   #11
Site Supporter
Site Supporter




Join Date: May 2023
Location: Quebec
Posts: 48
Original Poster
QuoteOriginally posted by AlwaysAl Quote
Originally purchased this lens as a replacement to my Tamron 17-50 mostly to accommodate full-length portraiture. As an aside, I had been disappointed with the Tamron, everything about it seemed second rate compared to the Tamron 28-75 which had been my go-to lens for many prior years. The Sigma ART seemed to offer a solution and, although pricey ( I was an early adopter), it was everything it claimed (and far better quality than some of the Sigma lenses I had previously owned). The Sigma had a steep learning curve but rapidly became one of my favourite lenses on the APS-C bodies. Any focusing issues I experienced could be attributed to my mistakes. The technology of the K-3 III bought a new life to all of my lenses (in varying degrees) but none as much as the perceived performance of the 18-35. When testing focus (with the myriad of poor focus related comments in my mind) I thought I had finally experience a manifestation of this phenomena. The reality was the lens/camera combination was focusing so quickly and silently (I'm a little deaf) I'd missed the correction as compared to that experienced with previous APS-C bodies. This lens, and the DA*50-135, have become my walk-around lenses. What's perhaps the worst thing with this pair; no WR but then neither am I.

https://www.pentaxforums.com/forums/members/1711-alwaysal/albums/3052-when-m...ture136172.jpg
Thank you @AlwaysAl. I would use it for full-length portraiture as well most of the time too.
12-22-2023, 07:53 AM - 1 Like   #12
Junior Member




Join Date: Jan 2023
Posts: 34
I just tried this combo out and wow, the K3iii really performs well with the Art 18-35 in Live View. I used to think this lens was a little sluggish to focus on the K3 and K-70, but it is very quick and confident now. If you're thinking about this lens, I'd recommend doing so.

If a demo video is of interest, let me know and I can quickly record a little bit of footage of the camera and lens in action.
12-22-2023, 10:56 AM   #13
Site Supporter
Site Supporter




Join Date: May 2023
Location: Quebec
Posts: 48
Original Poster
QuoteOriginally posted by colten.photo Quote
I just tried this combo out and wow, the K3iii really performs well with the Art 18-35 in Live View. I used to think this lens was a little sluggish to focus on the K3 and K-70, but it is very quick and confident now. If you're thinking about this lens, I'd recommend doing so.

If a demo video is of interest, let me know and I can quickly record a little bit of footage of the camera and lens in action.
Fantastic!This is the kind of feedback i was looking for.Thank you @colten.photo!
12-25-2023, 02:12 AM   #14
Pentaxian




Join Date: Sep 2017
Location: New York
Photos: Gallery | Albums
Posts: 1,206
I am and have a sample size of 1 but so far I've had almost nothing but excellent experiences with my 18-35 Art copy. On occasion I'll have to refocus a few times to get the object I want in perfect focus but generally I don't have any problems. I think I might actually need a focus correction of something like +1 but I haven't done a focus test with it at all. It's a lens I can do nothing but recommend completely.

(Forgot this was for the K-3III. I have a K-3II but I can't see it changing all that much aside from the faster AF of the Mark III)
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
art, art with k-3, f1.8 art, iii, iii live view, k-3, k-3 iii, k-mount, pentax lens, sigma, sigma 18-35 f1.8, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale - Sold: Pentax K-3 Limited Silver, Sigma 18-35 Art F1.8, Pentax K-S2 18-135, Metz M400 Tudor97 Sold Items 4 12-10-2019 09:56 PM
live view noise and smc dfa 100mm f2.8 macro lens not focusing in live view tommygunn84 Troubleshooting and Beginner Help 7 11-24-2016 08:59 PM
Typical live view humming, when not in live view. Unregistered User Pentax K-1 & K-1 II 8 05-05-2016 02:20 AM
sigma 18-35mm f1.8 Art or 35mm F1.8 ART ? Help needed ajaya Pentax SLR Lens Discussion 13 02-25-2014 08:11 PM



All times are GMT -7. The time now is 10:01 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top