Home · Register · Join Upload & Sell

Moderated by: Fred Miranda
Username  

  New fredmiranda.com Mobile Site
  New Feature: SMS Notification alert
  New Feature: Buy & Sell Watchlist
  

FM Forums | Canon Forum | Join Upload & Sell

  

Archive 2014 · New to me Sigma 35mm Art

  
 
campy
Offline
• • •
Upload & Sell: On
p.1 #1 · p.1 #1 · New to me Sigma 35mm Art


I picked up this lens used from a local store on Tuesday and have been taking some test shots around the yard and it seems to be ok. I have read about some of these lenses having focusing issues and would like to know if there is a specific way to test the lens for the focusing problems. I have until the middle of next week to return it if unhappy.


Sep 19, 2014 at 02:41 AM
Paul Mo
Offline
• • • • •
Upload & Sell: Off
p.1 #2 · p.1 #2 · New to me Sigma 35mm Art


Just shoot a lot and pay attention to focus points, download and check.


Sep 19, 2014 at 05:14 AM
kezeka
Offline
• • • •
Upload & Sell: Off
p.1 #3 · p.1 #3 · New to me Sigma 35mm Art


Set up a test in your house at 15-20 feet away and then pull the focus close to you, then AF and take the photo. The push the focus further from you, then AF and take the photo. Repeat those twice and download the pictures and see if the focus is off, and if so if it is focusing closer or further from you. Then make changes to the AF micro adjust to compensate.

Wide aperture primes often need to be calibrated to the camera just because so little is actually in the focal plane when your depth of field is so slim. That said, the sigma 35 art notoriously has problems establishing focus in low light but I haven't heard any issues in daylight other than some inconsistencies.



Sep 19, 2014 at 06:57 AM
cgarcia
Offline
• •
Upload & Sell: Off
p.1 #4 · p.1 #4 · New to me Sigma 35mm Art


My copy had backfocus when shooting at f/1.4 in far subjects (i.e. 15-30 meters away). Thus, noticeable at full size pictures (the subject could be "partially" in focus but with extra chromatic aberration that is absent when the focus is perfectly nailed). I adjusted the infinity setting with the Sigma dock and now I get great results wide open both in far and near subjects (a few months later I corrected also for the 0.7 meters distance, maybe indirectly affected by the infinity tuning -and this was because I was toying with dot-tune, in my normal use I didn't feel the need-).

In the near distances AF has always been perfect. Of course, for critical missions, live view is a must. I can't fairly compare this lens AF to others I have, since they aren't fast enough (the 35 Art already was fine without adjusting when stopped down). But I'm happy with the current AF performance and image quality is stunning.

Must add that my camera is a 6D.



Sep 19, 2014 at 07:16 AM
PhilDrinkwater
Offline
• • • •
Upload & Sell: Off
p.1 #5 · p.1 #5 · New to me Sigma 35mm Art


The most common issue is focus at distance, so shoot something 10-20ft away.

I also found mine less consistent than my 35L when doing continuous AF in relatively low light..



Sep 19, 2014 at 07:22 AM
campy
Offline
• • •
Upload & Sell: On
p.1 #6 · p.1 #6 · New to me Sigma 35mm Art


I have noticed a squeak if I put the focus ring on closest distance and then autofocus at infinity I hear a slight squeak about once or twice out of about 10 attempts. Is this potentially a serious problem? Also at the time I bought it I mentioned that there is no warranty and he made a comment that there are ways around that. Does anybody know what he may have meant?


Sep 19, 2014 at 03:35 PM
mmurph
Offline
• • • •
Upload & Sell: On
p.1 #7 · p.1 #7 · New to me Sigma 35mm Art


Roger Cicala at Lens Rentals has a pretty quick and pragmatic post on using the dock to adjust his lens:

http://www.lensrentals.com/blog/2013/06/sigma-optimization-pro-and-usb-dock

Basically, shoot at the different distances and look at where the focus falls. Once you have been through it once or twice, it is pretty easy.

He also makes the point that the Phase Detect Autofocus in most cameras has some slop. So to test just the lens and not the autofocus, use Live View and/or Live View with manual focus:

http://www.lensrentals.com/blog/2014/02/why-you-cant-optically-test-your-lens-with-autofocus

Sigma has excellent customer service and a 4 year warranty in the US. (Can't check your location on my phone right now.)

The lens must be less than 4 years old. If the shop sold it new, they may be able to send it in for tuning under the original sales receipt and date.

I **love** my Sigma 35 1.4 Art. I shoot it wide open even under low light/high ISO and it has been perfect. There are a number of "best practices" to help improve your keeper rate at 1.4:

1. You can't focus and recompose!!!

2. Use a cross type focus sensor directly where you want the focus point.

3. If you focus and hold, waiting for the right expression, use Servo Ai/ Continuous focus. If you lean or sway, or the subject does, you are changing by enough to blow your depth of field.

When I first shot my Canon 85 1.2 wide open, my keeper rate with focus and recompose was under 50%. This takes practice and knowledge to use effectively!

I have decided to whittle down my kit to only **the best** glass. So far that means the Canon 24-70 2.8 II, 70-200 2.8 II, and the Sigma 35 1.4 Art.

Looking forward to a lot more from Sigma in the Art line!



Sep 19, 2014 at 04:02 PM
cgarcia
Offline
• •
Upload & Sell: Off
p.1 #8 · p.1 #8 · New to me Sigma 35mm Art


campy wrote:
I have noticed a squeak if I put the focus ring on closest distance and then autofocus at infinity I hear a slight squeak about once or twice out of about 10 attempts. Is this potentially a serious problem? Also at the time I bought it I mentioned that there is no warranty and he made a comment that there are ways around that. Does anybody know what he may have meant?


I remember have heard occasionally rare AF sounds the first weeks. As if the lens were sometimes suffering a slight pain . Always indoors. But couldn't find a way to intentionally reproduce them. I don't know if it was the firmware update, or maybe simply I'm not keeping a close eye on it now...



Sep 19, 2014 at 04:24 PM
campy
Offline
• • •
Upload & Sell: On
p.1 #9 · p.1 #9 · New to me Sigma 35mm Art


cgarcia wrote:
I remember have heard occasionally rare AF sounds the first weeks. As if the lens were sometimes suffering a slight pain . Always indoors. But couldn't find a way to intentionally reproduce them. I don't know if it was the firmware update, or maybe simply I'm not keeping a close eye on it now...


Try turning the focus ring to minimum focus and then autofocus on something at some distance. Sometimes it's just a slight squeak and other times it's more noisy.



Sep 19, 2014 at 05:16 PM
Ulan
Offline
• •
Upload & Sell: Off
p.1 #10 · p.1 #10 · New to me Sigma 35mm Art


Hi Campy.

I use Spyder Lenscal and Sigma's USB dock for lens calibration (35 mm Art or 50 mm Art).

Life in a café by Inti Runa, on Flickr



Sep 21, 2014 at 06:15 AM
campy
Offline
• • •
Upload & Sell: On
p.1 #11 · p.1 #11 · New to me Sigma 35mm Art


The squeaking is all but gone for some reason. I did a micro adjust and it seems pretty sharp at f1.4. Would I get better results if I bought the dock?



Sep 23, 2014 at 06:41 PM
Guest

Guest
p.1 #12 · p.1 #12 · New to me Sigma 35mm Art


If you're happy with it now why mess with it


Sep 24, 2014 at 12:11 AM
mmurph
Offline
• • • •
Upload & Sell: On
p.1 #13 · p.1 #13 · New to me Sigma 35mm Art


Meant to post this in the thread on the 50 mm Art & dock ...

Edited on Sep 25, 2014 at 06:28 PM · View previous versions



Sep 25, 2014 at 02:03 PM
curious80
Offline
• • • •
Upload & Sell: Off
p.1 #14 · p.1 #14 · New to me Sigma 35mm Art


campy wrote:
The squeaking is all but gone for some reason. I did a micro adjust and it seems pretty sharp at f1.4. Would I get better results if I bought the dock?


Use live view with magnification to achieve critical manual focus, then compare that shot with the AF shot to see if they are comparable. That way you will know if you are losing something due to AF or not.



Sep 25, 2014 at 02:35 PM
dennisgibson
Offline
• • • •
Upload & Sell: Off
p.1 #15 · p.1 #15 · New to me Sigma 35mm Art


Still got the 35 Campy?


Sep 25, 2014 at 02:36 PM
campy
Offline
• • •
Upload & Sell: On
p.1 #16 · p.1 #16 · New to me Sigma 35mm Art


dennisgibson wrote:
Still got the 35 Campy?


Yes



Sep 25, 2014 at 03:33 PM





FM Forums | Canon Forum | Join Upload & Sell

    
 

You are not logged in. Login or Register

Username       Or Reset password



This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.