Gudge
Contributor
Time to stop lurking!
I use a 40mm extension with the Subal SWC dome port and a +4 dioptre (though I think I probably don't need it, I'll have to try it without when I get my lens back from Alcina). Alcina is using a 40mm extension with the Subal DP-FE dome port and no dioptre.I don't own the smaller dome port - the buddy that owns this lens uses the smaller one with a +4 dioptre.
About this close on my rig with a 72/77 step up ring between the lens and the dioptre:Yes my question was more on how physically close the lens gets to the inside of the dome when zoomed out to 70mm... just ball park numbers... no need to get the tape measure out...
![70mm.jpg](http://www.gudgeon.id.au/forum/70mm.jpg)