Thanks Tom, Frank for your words.
Anyway the 235mm, I have, could show the similar or less, but this is.
I left the 305mm one year ago because of the site quality being worst with time being.
I invest Something in South of France and expect Something better but remaining on expectations..
We will see.
I tried a 150mm apo on borrow from an us observer, got results that were just a little above from my istar 150mm F10 achro.
So the istar remained enough for.
Indeed for me a 180-200 would be a must enough, I know, having in past a 200mm vixen cass and a russian cass 180mm, sold..
Hope a 200mm CC like the 154mm.Here is a report of uranus performed last 20th november with 150mm apertures.
Average to almost good images were met Under 324 and 362x magnifications.
Still the similar banding pattern catched last 8th.
However a variability was captured on the temperate band north, its move was revealed after 3H of planet rotation.
Still a dark pôle but may be fainter.
Indeed the contrasts are considerably enhanced for drawing.
Personnally my personal limit for U is (D-d)x strehl optical global, so, 150mm x 0 93 = 139mm (refractor)
(154mm -54) x 0.95 =95mm (for the CC). where the 150mm achromat is obvious on and the CC154 remained on the threeshold on my vision. When 7/10 images are met close to U, therefore the 150 achromat is obvious.
The CC154 can be a confirmation, not less aperture in cause
Hope this is a clarification here, if any.
The variability is there.