This is key for those of us who like shooting f/2.8 or wider. By creating a very shallow depth of field you can really zero in one how accurate the focus is. In taking the test photos you will want to open your lens pretty wide. Once you have that set up, place a tape measure alongside the object starting about 2 feet behind the object and extending at least 4 feet in front of it. You will want to make sure there were no light issues distracting from the way the lens is focusing. It is helpful to pick an object with a relatively easy focus point and set it up in high contrast light with very little noise. Once you have done that, simply follow the steps below and your focus will be as tack-sharp as ever! Priced at around $65, the USB calibration doc is relatively inexpensive (especially in comparison to what you pay for the lens itself!), and all it takes it a little set-up and a few tweaks to get your focus exactly where you want it.Īfter purchasing the calibration doc, the first thing you will want to do is download the Sigma Optimization Pro calibration software to your computer (click HERE for the link to the software). Further, many 35mm lovers like me enjoy shooting with the lens wide open, so a slight discrepancy in how the lens is focusing can result in images that are significantly different from what you intended.įortunately, Sigma offers a USB Calibration Doc to help you fine tune the focus of your lens.

This is a lament I hear frequently around the photography community. Unfortunately, now and again this lens starts to miss focus. If I had to choose one lens to live with for the rest of my life, it would undoubtedly be my Sigma 35mm 1.4. There is no lens I love more than my Sigma 35mm 1.4 ART.

Sigma optimization pro