Soft spot in center of image?

Hello, this is my first time posting here and I'm new to the blackmagic camera as well. I have the Blackmagic Cinema Camera MTF. I have noticed an out of focus spot in the center of the image when I use my SLR Magic HyperPrime CINE 12 mm T1.6 lens. It is quite large but only seems to appear randomly. I have checked and cleaned both the lens and the sensor and have made sure there are not scratches or the like. The spot does not seem to appear on more close up shots but is very noticeable on long distance shots (image below). I have no idea what the problem may be and would appreciate any help. Im sure I've left out some vital info so just let me know if you need to know anything else.



The boat in the port in the center of the image is out of focus Sorry for crap quality of image its a screen shot.

The boat in the port in the center of the image is out of focus Sorry for crap quality of image its a screen shot.

Screen Shot JPG.jpg (631.3 KiB) Viewed 1078 times

Are you shooting wide open, as in at T1.6?

Most lenses are not at their best wide open as you get a bit of blooming.

Same applies if you stop all the way down.

If you are shooting wide open what fitters are you using to control exposure?

Are you shooting wide open, as in at T1.6?

Most lenses are not at their best wide open as you get a bit of blooming.

Same applies if you stop all the way down.

If you are shooting wide open what fitters are you using to control exposure?

This was not all the way up or down however it was stopped down a bit to compensate for the bright white walls. I use a ND filter as well. I have noticed it both when shooting wide open but this doesn't seem to affect it drastically... it just seems to come and go. Im stumped. Also if it helps someone else was using the equipment prior to me and i noticed it in their test footage first... Not sure what happened while it was in their possession.

There's not much that could have happened to produce this kind of failure. Can you determine if the problem is isolated to one lens, or does it affect the camera with all lenses?