Today I finally can perform using a tripod, the desired long-term exposures. As a camera, I used a Fujifilm X-E2 together with the appropriate filter size for Fujinon lens XF18-88mm.
Unfortunately, the result was not at all satisfactory. I'd like to publish the test pictures here; but we can not, unfortunately.
When the filter who actually really long exposures result settings, emerged Cruciform, massive shadows in the image. It may be that at longer focal lengths, as the 18mm used this cross the center fills. For landscape and architectural shots, however, you can completely forget the filter. I'm going to send him back.
