ERP1978 wrote in post #18318637
I actually just purchased this about a week ago and worked with the lens and USB dock over the weekend. I tried calibrating it with the USB dock and thought I had the focus adjustments taken care of pretty well. However, the test shots showed otherwise as the focus was all over the place. I had never tried to calibrate a lens before so I know there was some user error the first time.
I tried the calibration again and the second time was definitely more successful, but I still had front focusing issues. It is a time consuming process and would be well worth it if you were able to resolve all the focus issues with the dock, but it is very time consuming. So, the lens is going back tomorrow unfortunately. I was really hoping for better success as I had my eye on this lens for awhile.
So, I would like to retract my previous comments about this lens. I went ahead and ordered another copy to try out and see if there could have potentially been a problem with the first copy. As it turns out, it appears there may have been. It was front focusing horribly and that is not present in this second copy, although some slight front focusing does exist. I also noticed this lens was much, much sharper out of the box. I have been working on the calibration a little bit today and have definitely made some improvements across the 16 different calibration points. Yes, the calibration can take a little bit of time, but seems to be going quicker than with the first lens...perhaps due to the potential defect the first lens had. With a little more tweaking, I think this lens will be perfect and exactly what I was expecting. Glad I gave this lens another chance as I now have a winner!
IMAGE LINK: https://photos.smugmug.com …ement_062-XL.jpg&lb=1&s=A 
IMAGE LINK: https://photos.smugmug.com …nt_062-BW-XL.jpg&lb=1&s=A 
IMAGE LINK: https://photos.smugmug.com …ement_063-XL.jpg&lb=1&s=A 
IMAGE LINK: https://photos.smugmug.com …nt_063-BW-XL.jpg&lb=1&s=A 
I really need to get on it. 
