inverted cone
they are more effective for their size
You did not say what size you needed eg
I use a 42 mm Leitz clip on on my Canon LTM wides it needs blue tack and a Canon filter...
bodges are us.
there was a 48 mm rubber screw in
but a step ring to 49 mm and low profile non flared generic should be ok cept direct into low sun.
clamp on series 7 filter ring and series hood more difficult to source
The lens should be ok if it is not fogged internally
This is a home brew hood with the grazing angle calculated for its Graftar f/4.5 103mm using a sketch and a bit of trig, and machined out of solid acetal bar on the lathe.
It is a press fit on the Graftar and the inside is rough turned.
It is a bit stumpy so it can stay on when the camera is folded.
It is nice work indeed, I was once an engineer and I know a push fit for this hood to go on the lens tightly enough it needs to be only about 2 thou. larger.