I recently asked a question and you responded.
Magnification if it occurs during fluoroscopy increases radiation dose a great deal.
For instance 2 times magnification mode increases radiation dose by four times. The technician had me reposition myself and he had the fluoro on while he watched and told me where to move and turn. The machine was on for close to 5 minutes even though the test was longer.
Is there an agency that would know the answers to my previous question? The link you provided is a radiation agency but they do not provide that information.
Radiation dose does increase by decreasing the distance between the radiation source and the body part. During fluoroscopy, the distance between the radiation source and the body is fixed, so the exposure remains constant.
Magnification in fluoroscopy is achieved by varying the distance between the receptor and the source, which would not change the exposure dose. These days, magnification is also achieved by digitally manipulating the image, which also has no effect on dose.
I don't think I can improve upon my previous answer. I recommend you ask my colleague, Michael K. He is a radiologist and may have a better answer for you.
Sorry I couldn't have been more help,