Hi Timothy, yes the issue is known and being worked on as we speak (write).
The current transition is a fade-out (of the old image) and then fade-in (new image) which exposes the white background visible like a short flash.
The next release will have a cross-fade effect, which means the old image will fade into the new one straight away. After that, a slide effect is planned for another release.
In any case, the upcoming version should not take too long now 🙂