As I've mentioned before on the site, I own and love the Sony Zeiss 24mm f/1.8 lens. It is made for the smaller APSC sensor on the Sony NEX series plus the newer Alpha A6000 and its siblings.
When I decided to upgrade from the NEX 7 and purchase the full frame A7, one of the concerns and bummers was that this great lens doesn't cover the full frame Sony sensor.
I noticed awhile ago that the back of the lens has a plastic baffle that is held in place with 3 small phillips head screws, but I didn't take it off and instead scoured the internet to see if someone else had taken it off. I was wondering if the lens might give full or even slightly better coverage without it.
I'll spoil the suspense. You don't get full coverage. I didn't expect to, but I hadn't seen anyone mention that there is also a sticker ring on the end of the baffle that makes the image circle even smaller. So, if you own this lens, here are some photos that show what you get if you take off the sticker or the whole baffle.
It peels right off with the adhesive intact and I just stuck it to the inside of that lens' rear cap in case I ever want to put it back on.
As you can see, taking the baffle off makes a difference. You don't get full sensor coverage, but it does give more coverage. In addition, you can also see that I put the baffle back on, but without the sticker. Though the plastic baffle makes for sharper, edges to the shadow, the coverage is almost identical.
For me, the tradeoff is worth it to protect the internals and exposed circuit board that lies just underneath the baffle.
So, you still have to do something with that black mess at the corners, but that's easy in Lightroom. I took a similar photo with my kit 28mm FE lens at its widest setting and then cropped the photos from the 24mm lens to a tiny bit larger field of view than the 28mm I left a little bit of vignette in the corners so you can see what you have to work with.
With the sticker removed, I find that I can get the most coverage area with a 4x5 crop and the resulting image is roughly 17.9 megapixels. If I want to stick with a 2x3 format, it comes in at 16.9megapixels.
In addition if you are cropping to 4x5, the top and bottom borders are roughly what you see in-camera, which makes composition easier.
So, you end up with about a 28mm equivalent, and the aperture of 1.8 still gives nice performance in lower light situations. I know for a lot of folks this might seem like a lot of hassle, but I'm simply not ready to get rid of this lens yet.