Thank you @dannybgoode.
I'm using a f/5 150/750 scope along with an ASI224 = quite narrow FOF. I know this camera is meant for planetary, but since we're out of season I'm experimenting with DSO imaging. I cannot use a guiding solution because the mount (EQ3 GOTOrized) would be overweight (if not yet).
Problems finding objects: poor accuracy. Faint ones impossible to locate.
Image capture: 90% of the exposures over 20sec are invalid.
My intention is to minimize those errors with the means available: current gear, experts advice, patience and time. On top of that, I consider myself very meticulous and perfectionist (on the verge of OCD 😂), so all this annoys me a bit. I assume this frustration is part of the hobby though.