I recommend you try gaffer tape instead of duct tape.
Advantages:
Remains flexible and removable forever.
Looks nicer, a cool matte black or manynother colors.
Where I get off making this recommendation:
I needed a light-excluding bellows for a photographic project. I made one using black illustration stock and gaffer tape. It worked extremely well on the first version and held up to hundreds of cycles of extension/compression. My application was sensitive to pinhole light leakage and there was none.
It would have lasted longer but that was the end of that project.
Duct tape and cardboard solutions to questions like “How do I get these two pieces of photography equipment to work together?”
I recommend you try gaffer tape instead of duct tape.
Advantages:
Where I get off making this recommendation:
I needed a light-excluding bellows for a photographic project. I made one using black illustration stock and gaffer tape. It worked extremely well on the first version and held up to hundreds of cycles of extension/compression. My application was sensitive to pinhole light leakage and there was none.
It would have lasted longer but that was the end of that project.
My two cents. I love DIY stuff!