Hi all. I recently acquired my first lens designed for a full frame sensor that I will be using on my cropped sensor body. The Sigma 105mm f/2.8 EX DG OS HSM Macro on my Nikon D3200. Please forgive my ignorance in advance for the below
. So in my research on this lens I read that it has the equivalent of 168mm on a cropped body. When shooting on a full sensor body wit a 1:1 focus setting the focal point should be ~1.02 feet. When I shoot on my cropped body being that it is acting like a 168mm I would presume I need to get back further away further from the subject to get the same object in focus at the 1:1 setting. This does not seem to be the case. Unless I am totally off on all of the above then my whole understand goes to pot. But if not my first question would be Is the 1.02ft. document distance from the sensor to the subject or from the lens to the subject? I assume its from sensor to subject. At any rate when I shoot a subject with a 1:1 macro focus setting and have said subject in focus my lens is right at 5 inches from the subject and the sensor is 11.5inches away. Ahh did I just answer my own question, LOL. someone please confirm - I'm still trying to grasp all of this. My sensor is at the roughly 1 foot from the subject but since it is artificially 168mm equiv but really on a cropped sensor I'm still at 105 its just cropped and I'm loosing part of the image not really having to backup to the 168, hence the hole cropped sensor definition? Meaning I cannot backup to get the same content extents in my frame with this lens on this body at a 1:1 and in focus, i would have to give up the 1:1 or blow the focus, correct? Also in that same thought, if correct is that If I put this lens on a full body reshot with all things being equal, the subject distance would be the same but I would get more content in my frame for the final picture?