My beloved Rokinon 7.5mm Fisheye had quickly rose through the rank to become my most used, if not overused, lens. Despite being well cared for, developed a stiff focus ring over time. Upon doing some research, it seems many Rokinon/Samyang fisheye users suffered from the same issue. I took apart my lens today and it turned out to be an easy fix.
Tools I used were a set of computer screwdrivers with 2.5 flat bit and 00 Philips head bit, dental tools, and needle-tip precision lubricator. Lens cleaning cloth and dust blower are optional to keep the lens clean throughout the process. In my research, someone else used jeweler screwdrivers to pry the cover off which may be better but I didn’t have that.
Removing the Lens Ring
First I removed the lens ring with the Rokinon label. I started using the flat bit to pry it off but it’s prone to scratching the paint and eventually used the dental tools to pry it off. You can still scratch it with the dental tools but it seems less abrasive. The ring is held on by double sided tape, but only on the sides of the hood with the short petals. The closer to the UMC or Rokinon label on the top or bottom, respectively, the easier it lifts up. Unfortunately, that is also where the deep petals are obstructing your tools. I ended up prying it off at the corners then working my way around.
Unscrewing the Hood
After removing the lens ring, it will reveal the four screws holding on the lens hood. Remove these with a 00 Philips head screw driver and the focus ring should immediately feels a lot smoother. The whole focus ring can be lifted up at this point. I assume it is a combination of these screws being too tight and the lubricant being dry that causes the ring to be stiff. I could have possibly just loosen these screws and call it a day but since I had already unscrewed it, I added a few drops of lube throughout the focus ring. I clean off the lens, reverse the steps, and voila: lens is as good as new.
And now for some photos from this fantastic lens: