Thanks for the info everyone.
See EAA or Night Vision Forums for alternative approaches. I've used EAA to see almost all of the Herschel 400 objects, including those tiny dim galaxies (Mag 11-12) under Bortle 7/8 skies.
I think EAA is something I could see myself getting into for sure, but I right now I really like the raw seeing aspect of the hobby. It's like my mind is directly connected to what I'm looking at, instead of seeing an interpretation.
Dark skies are much more valuable than aperture. Aperture gets wasted under light pollution. If you ever take advantage of the 21.8 sky you have available the drive will seem much more worthwhile. Your XT10 and fine eyepiece kit will certainly show thousands more galaxies and other objects from under dark skies. The objects you now observe will be more extended with much more available detail. It's an entire new level of capability that dark sky brings. I never even bother to use the Starmaster from town as it isn't productive. If I had to choose between my XT10i from a dark site and the 16" from town I would choose the 10" from a dark site.
And judging under a large moon isn't effective.
You have some real treats waiting for you!
You're getting me all excited!
Have you been out to the HAS site in Columbus? Plenty dark enough for serious observing and only 1 1/2 hour drive from downtown Houston.
Would be a good place to see just how deep you can go and still be close to home!
I have not but I've read about it on the site. I think that's actually a really good idea as it would provide me a realistic test of both a darker site and a longer drive, including overnight stay in a tent. Maybe that would satiate me for a while and give me more time to find a property that would better fit our other needs. I think I'll sign up. Thanks for the reminder.
Something I’ve observed....
I think my favorite way to observe right now is just putting on a low mag and panning around. Not being very familiar with where things are, it's exciting to "discover" something new. Just the other night I was in my driveway cruising southeast of Orion and ran across a few OC's that I hadn't see yet. I would like to be able to do this very same thing with galaxies... just happen across them, and then ID them.
At a dark site a 10" readily shows 14 to 15 mag galaxies.
Galaxies and diffuse nebula observing is primarily about contrast between the night sky and fixed surface brightness of the object. More aperture doesn't change this surface brightness delta. If the contrast is too poor to show the galaxy, you won't see it, even though in dark skies the galaxy would be easily seen.
M110 is a good example for this. Despite being about 8.1 visual magnitude, it is diffuse with only moderately higher surface brightness to its core. It is easy and obvious in dark sky with nearly any aperture, but hard to detect in light polluted conditions. In ~19 MPSAS conditions in town it is just visible as a faint averted vision haze if transparency is very good--primarily because it has some brightening to the center that is detectable. I calculate its overall visual surface brightness as ~22.7 MPSAS. A 22.7 - 19 = 3.7 MPSAS delta is difficult to pick up, even for someone who knows exactly where to look and what they are looking for. Aperture is not the problem.
I'm able to see M110 at the 19.6 site fairly easily. No structure, but I haven't really seen any structure to any galaxy yet... not obvious anyway.
Dark skies. As Redbetter says, a 10" in truly dark skies will not have an issue with seeing galaxies until they pass mag.14.
Then it will be a matter of transparency and experience to see fainter.
I suspect there may be other reasons why you may be struggling to see more galaxies from your Bortle 5 skies....
I'm sure inexperience has plenty to do with it, but also probably my observing method. I generally just use Sky Safari (pro) and look zoom in and start searching for the first thing I see. Not very methodical for sure. And I also am aware that magnitude isn't really the best way to determine if a galaxy is bright enough to see, but I can't figure out a way to filter surface brightness on any of my apps. They seem to love magnitude and SB seems to be an afterthought. But it could be my inexperience with using those apps too.
For some reference, at Brazos Bend SP, which I recently measured at 19.65 upon arrival around 7p and 19.68 upon departure at 9:30p, some objects that were at what I would consider the edge of my ability to locate/see are:
M74 (logbook says "faintest of smudges", and "extremely faint galaxy, averted vision only" on two separate nights)
NGC 288 (GC) ("edge of visibility with direct vision, @30mm just a cloud, at 11mm start see individual grains of stars")
NGC 253 ("very faint smudge w/ 20mm")
Attempted NGC 247, couldn't locate
M33 ("very faint galaxy in Triangulum")
Does this seem to be about right? Does anyone have any suggestions for dim targets at the edge of my conditions that I should be able to find? I wouldn't mind an assignment for my next time out. That's would give me some direction at least and I can report back how I ended up...
Thanks again for the feedback everyone. Much appreciated.