Question about Sigma 30mm f/1.4 EX DC HSM for Sigma

1 Answer

Front/Back Focus Problem at Sigma 30mm F1.4 Lens

I just bought my Sigma Lens 30mm f1.4, i just realised that it has minor focusing problem. With apperture open wide (that's f1.4) and my subject distance is around 2 feets 6 inches, i focus at one point but the result is the sharp image is slightly at the back of my focus point (my original focus point is blur). I dont know whether this is front focus problem or back focus. I use Sony Alpha A100 DSLR. Please help me.


Abdul Malik

Posted by on

  • cottage4 Mar 19, 2009

    i was focusing at 2 persons a meter away. when the photo was developed, it was the wall behind my subjects that was clear. my subjects were slightly blurred.



1 Answer

  • Level 1:

    An expert who has achieved level 1.


    An expert who has answered 20 questions.


    An expert that hasĀ over 10 points.


    An expert whose answer gotĀ voted for 2 times.

  • Contributor
  • 36 Answers

Hello Abdul!
I recommend that you print this test chart:
Just print it on an ordinary paper, then put it on a table, and take a picture at it from a 45 degree angle, using the center focusing point only, aimed at the thicker line in the middle. The numers are centimeters. Take the test picture at f/1.4. Make sure you have good light so you get a fast shutter time. If you have a tripod, mount the camera on the tripod prior to taking the test picture.
Then examine the picture in your computer, zoomed to 100%. Now it should be clear wheter you got back- or front focus, and how large the problem is.
Unfortunately, there is no way for you to adjust the camera and lens combination yourself, you will have to send/bring the camera to an autorized camera workshop. This is covered by the warranty.
Hope this helps!

Posted on Jan 19, 2009


1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya Expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repair professionals here in the US.
click here to Talk to an Expert (only for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017


Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

No focus at 15mm

I ever have same problem with my canon 18-55mm, it won;t focus in certain range zoom, then i see that the flexible cable inside the lens was ripped.

Jul 20, 2013 | Sigma 15-30/3.5-4.5 EX Aspherical DG...

1 Answer


How new is the lens? In or out of warranty? If out or warranty most likely solution is to find a Sigma authorized repair shop because your description sounds like the auto-focus motor gear has failed. If in warranty, check out for repair sites and also download the SIGMA_SERVICE_REQUEST.PDF. I've only had to deal with Sigma once on warranty matter and they were very helpful, provided UPS authorization for shipping on their nickel.

Oct 15, 2010 | Sigma 70-300mm f/4-5.6 DG APO Macro Lens

2 Answers

I have a 28-200 sigma D nikon fit lens. In auto focus when you get to1.5 metre bottom focus it will not return to up focus . It will only up focus if you slightly turn focus ring back may be 1mm. It sounds...

If you take it to pieces, you will end up with a (hopefully complete) kit of parts which you will have to pay a repairer to re-assemble for you. Your choice.

Jan 08, 2018 | Sigma AF 28-200 Lens

1 Answer

Focus ring will not move below 5 feet. Can't focus on things closer than that - AF or MF.

There's nothing you can do yourself to fix it, the lens should focus down to 0.4m (15").

The lens comes with an automatic one year manufacturer's warranty, which extends by another three years if you registered the warranty so I suggest that you return the lens to Sigma for repair.

Note that any evidence of misuse or unauthorised repair attempts automatically invalidate the warranty.

Mar 14, 2010 | Sigma 30mm f/1.4 EX DC HSM for Sigma

1 Answer

How do you use the manual focus feature. My friend just bought a new one and is having trouble with this part of the lens. I have one for my canon and there is a setting for it

Set either the camera or lens (or both) to manual focus. Most Nikon cameras have the focus selector switch on the front, under the lens release button.

Look through the viewfinder and turn the focus ring until the image (or at least the subject) appears sharp. A green light will light up when the camera thinks the subject under the currently selected focus sensor is sharp.

Sep 18, 2009 | Sigma 150mm f/2.8 EX APO Macro DG HSM for...

1 Answer

Sigma 70-300 mm lens wont focus

I was focusing to close to the subject & too much glare from a church window.

Sep 26, 2008 | Sigma AF 70-300mm f/4.0-5.6 DL Macro Super...

1 Answer

Sigma 28-300 3.5-6.3 won't focus

Did it ever work on this camera?
I have seen some Sigma lenses that are auto focus on canon film cameras but then when put on the digital they dont work right. If you have used it on this camera then make sure the lens is clean.sometimes dirt on the front wil make it try focusing on the dirt. Next try focusing in manual focus to make sure the focus is working. Then take the lens off and then put it back on and make sure it clicks into place.

Let me know if none of those things work. also make sure to try focus on something close and somthing far away.

let me know how it works,

Jun 26, 2008 | Sigma 24-70mm F3.5-5.6 AF Zoom Lens

1 Answer

Auto focus will not focus. lens problem or camera problem?

A dirty filter, front, or rear optic can cause the lens to seek

Feb 03, 2008 | Minolta Maxxum 300si 35mm SLR Camera

1 Answer


If if won't focus manually then there is a problem with the helicoid and you'll need it professionally repaired. Don't force it.

Nov 04, 2007 | Sigma 30mm f/1.4 EX DC HSM for Sigma

Not finding what you are looking for?
Sigma 30mm f/1.4 EX DC HSM for Sigma Logo

1,589 people viewed this question

Ask a Question

Usually answered in minutes!

Top Sigma Cameras Experts


Level 3 Expert

102366 Answers


Level 3 Expert

3289 Answers


Level 2 Expert

254 Answers

Are you a Sigma Camera Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides