First of all, I understand if the camera isnt the best or the lens is garbage, but the camera was a gift and the lens was cheap. I have this issue where when I install this lens and have it on autofocus, it works and focuses clearly. The issues happen when I set it to manual focus. Through the view finder and the screen the image is completely clear and in focus, but when I take a picture the image all of a sudden becomes very blurry as if I didnt even attempt to put it in focus. I dont understand what the issue can be and is it even repairable?
It would help to see a few samples if possible of what the images are. There are a number of things her to consider. Third party inexpensive lens could be soft; could be the issue, other lenses would perform well if that is the case. View finder shows focus you have but does not show depth of field, at 1.4 you will only have centimeters of sharpness. Diopter, it could have been set for someone with glasses, but if your using auto focus it still should not have impacted the image as it would change the sharpness of the viewfinder not the sensor looking through the lens. https://www.bhphotovideo.com/explora/photography/tips-and-solutions/calibrating-diopter-your-camera Lastly the camera could have issue with focusing and need repair, but that is not likely and it may be easier to just get a different camera as these are pretty inexpensive used. Lens would perform fine on other cameras. You will need to test several things to see what the issue is.
