[TerryL]

Hello Folks,
My 43 seemed soft, at first. A few members advised me to check the lens manually. So, I manual focused through Live view, on a tripod, with SR off, and a 2 second delay. At 1.9, it was very acceptable. The lens got even better at 2.8 and 3.2. I do think the lens is a keeper. Now, I want to set up the auto focus. My question is, what is front focus and back focus? Also, how do I know I determine if use a negative or positive adjustment? My last question is, where do I find these adjustments in the camera. I used to know, but have forgotten. My method of testing is with a long metal ruler, set at 45 degrees.
Thank you very much.
Terry

[Adam]

It does sound like a calibration issue in that case, though it may also be related to your focusing technique.

In any case, all of your questions are answered below. I strongly recommend that you might up the calibration tool for accurate measurements:

Fixing Front and Back Focus - Introduction - In-Depth Articles

[TerryL]

It does sound like a calibration issue in that case, though it may also be related to your focusing technique.

In any case, all of your questions are answered below. I strongly recommend that you might up the calibration tool for accurate measurements:

Fixing Front and Back Focus - Introduction - In-Depth Articles

Thank you, Adam.
Exactly what do you mean by uping the calibration tool for accurate measurements. And, how much do I increase it? Thank you so much.
Terry

[Adam]

Thank you, Adam.
Exactly what do you mean by uping the calibration tool for accurate measurements. And, how much do I increase it? Thank you so much.
Terry

I meant getting the lens align (calibration tool). As for how much to increase the values in the camera, all that is covered in the article.

Adam
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[mikesbike]

It looks like you have a very good copy of that lens, since sharpness is already quite good at f/1.9 and gets better as it is stopped down, and should be great by f/2.8 by your comments. This is a very fine lens, and you've shown is it is right on target for sharpness.

As a quick test for AF front or back focus, I simply arrange rather shallow vertical objects very close together, these having some features upon them to focus on, set each at a close distance in front of or behind the other as to distance, center AF sensor only, and with the lens wide open select a feature upon each object on which to focus and see if your AF actually does focus exactly on that feature you have trained on. Make sure your shutter speed is sufficiently high for a hand-held shot, or even better, use a tripod. Do this with each of these objects to make sure of accuracy. And several times just to make sure the AF was not off just on one shot. Also, use the back AF button or the half-press more than once for each shot for any fine-tuning of focus that may be needed. The spot you trained on with each of the objects should be the sharpest spot in the outcome, while the other areas at different distances are softer. If the lens passes this test with flying colors, I don't bother going any farther with a more exacting test setup, unless I find indications of an AF problem during subsequent actual use.

[TerryL]

It looks like you have a very good copy of that lens, since sharpness is already quite good at f/1.9 and gets better as it is stopped down, and should be great by f/2.8 by your comments. This is a very fine lens, and you've shown is it is right on target for sharpness.

As a quick test for AF front or back focus, I simply arrange rather shallow vertical objects very close together, these having some features upon them to focus on, set each at a close distance in front of or behind the other as to distance, center AF sensor only, and with the lens wide open select a feature upon each object on which to focus and see if your AF actually does focus exactly on that feature you have trained on. Make sure your shutter speed is sufficiently high for a hand-held shot, or even better, use a tripod. Do this with each of these objects to make sure of accuracy. And several times just to make sure the AF was not off just on one shot. Also, use the back AF button or the half-press more than once for each shot for any fine-tuning of focus that may be needed. The spot you trained on with each of the objects should be the sharpest spot in the outcome, while the other areas at different distances are softer. If the lens passes this test with flying colors, I don't bother going any farther with a more exacting test setup, unless I find indications of an AF problem during subsequent actual use.

Hi Mike,
Thank you for the tips. I was able to get it calibrated. It took -4. I am quite happy with it now. Not like my 31 or 77, though. It doesn't even compete.
Terry

---------- Post added 04-04-18 at 02:12 PM ----------

I meant getting the lens align (calibration tool). As for how much to increase the values in the camera, all that is covered in the article.

Adam,
Thank you for the link. I will definitely get one of those.
Terry

[tbelf]

I am quite happy with it now. Not like my 31 or 77, though

Can't comment on the 77, but having thought that my finally acquiring the 31mm would result in the 'shelf' for my 43, I couldn't have been more wrong. There is something about the FOV of 43mm on crop that I just love!