I’m not sure about the apertures of those scopes. Could you enlighten me please?
Experience from my Sycorax adventure last year suggests that 21.0 or brighter should be possible with my 40cm unfiltered iand with decent seeing. When the seeing is >10 arcsec, which it has been quite often recently, dilution by sky background can be substantial.
Despite my “silliness” quip, is there any value from taking unfiltered measurements? If so I may repeat the experiment as I’ve essentially no interest in taking images of no scientific importance. If there were a SN in M88 to be discovered on the other hand …