Sorry for the confusion,
What I meant was, when using a WA converter on my camera, it will vignett a little(I know for sure because I'm using a modified mount and have tested with 67mm filters which VERY slightly vignetts so these adapters, even the raynox ones at 58mm would definitely vignett).
On my G7 which is a 35mm * 0.2X = 7mm with vignetts
If I zoom in a little, maybe to 70mm * 0.2X = 14mm, it is still way wider than my default 35mm but with less/no vignetting now. The question was whether in this slightly zoomed in situation, will I still have 180º horizontal coverage?
Heres an example taken at the lens at wide:
technically I could zoom in enough until I get only dark corners(bigger red frame) which is probably still 180º coverage, but if I zoom in further until I do not get any dark corners(Smaller red frame), would it still appear like the smaller red frame? ie. still wide coverage?
What i'm trying to achieve is an increase in coverage(FE or not is actually quite secondary), and getting a "sweet spot" between the 0.2X FE(super WA but high distortions) and the 0.7X WA(not as wide but also less distortions) converters.
Sorry about this but don't really have the resources to splurge on various converters to test for myself so just hoping your experience with the several converters might shed some light on my queries. The few converters I'm considering now are the Opeteka 0.25X FE, Raynox 0.66X and Raynox 0.7X.
Thanks for reading!