We've just received the new film holders for the SP-445. There are some pretty obvious modifications:
1. We added cutouts but left a narrow strip as a sheet separator. This allows for better chemical flow behind the film.
2. We removed the ridges on sheet separator. (Frankly, we debated even keeping the separator, we tested with and without and didn't see any difference.) In the end, we decided to leave it; if you don't like, it can be cut out in about a minute.
3. We also added a finger notch at the top; makes it easier to get a grip on the film.
4. Here's the modification you didn't notice: we added ridges under the hold down fingers. These are rather subtle (and really hard to photograph), so here's a closeup rendering:
In the above image, you're looking through the slot at the underside of the hold down finger on the opposite side of the film holder (that was perfectly clear, right?) The ridges are only about 0.01" high but help keep the film from "sticking" to the plastic.
The new film holders are a bit lighter and feel a bit more "flexible" but are functionally the same as the original.
We still have a few of the original style available. Why would anyone want the old version? If you're shooting really thin film, say you have a freezer full of old Kodak film packs, you might prefer the original design. Also, if you want to modify a holder for 9x12 or glass plates. Or, maybe you just don't want to change what's working for you.
All new SP-445's will come with the new film holders; (unless you request the original). They will also be available on our website for sale separately.