Many thanks for sharing your experience.
Honestly, looking back at the last 10 pages, your widefield shots are exactly what I'm going for. And they're among the best I've ever seen -- on this forum or elsewhere! If I could get even one image similar to yours on my upcoming trip to the PNW, I'd be more than happy with my iOptron purchase.
A few more questions, on that note, using this post as a reference point:
1) When you say "4 shots for the sky, 4 shots for the foreground" -- do you mean you're only stitching together 8 separate pano frames, and there's no stacking involved for any portion of the image?
2) How do you get a perfect series of frames for stitching while using the iOptron mount? For daytime panos, I just rotate the pano base of the ballhead -- but doing this with the base of the iOptron would obviously wreck the polar alignment.
3) Do you shoot any dark frames and/or bias frames for these widefield landscape shots? If so, do you shoot them for each of the 8 frames? If not, do you use the in-camera LENR? Any moonless 2+ minute landscape shots I've tried have been fairly horrific in terms of hot pixels and purple amp glow, with LENR only helping to tame the problem, rather than eliminate it. Your foreground results here look astonishingly clean for the type of exposure settings you list (unless there was some ambient or moon lighting).
4) I take it you don't use any specialized astro software like DSS or PixInsight for the widefield stuff?
Thanks, where in the PacNW are you headed? I lived in Portland for 11 years so I can provide advice for the Oregon/SW Washington area in terms of locations if you'd like.
For your questions:
1) Yes, when I say X number of shots it refers to a panorama, unless I specifically say I stacked for an image I am always doing panorama with multiple shots.
2) I've just gotten used to loosening my ballhead and rotating the camera without disturbing the polar alignment, it takes practice and will depend on your specific ballhead, mine is fairly easy to loosen without throwing off the alignment. Also keep in mind that for the very wide angle lenses (like 24mm or even wider) you don't need an exact polar alignment for the 2-5 minute exposures. Hell, I've done a "blind" polar alignment in a cave where I used a compass to find north and leveled the tripod as best as I could and I still managed to get 1 minute exposures at 24mm with no star trailing. The wider the angle the more forgiving your polar alignment can be.
3) With the widefield landscapes I don't do any calibration frames, no darks/bias/flat frames at all, nor do I use the built in LENR since it doubles your time for a single exposure. Those shots you linked to had no moonlight, the first shot had some very residual light from the end of astronomical twilight (they were shot at ~10:30PM), but otherwise it's pitch black. Obviously the colder outside it is the better off you'll be in terms of sensor noise, if you are shooting in 80+ degree temps it will be hard to avoid having a lot of sensor noise in your long shots. Generally I can take up to 5 minute exposures in truly dark sites (bortle 1/2) and collect enough light to produce foreground shots like those, I usually raise my ISO to 1600 and shoot wide open for the aperture and that's good enough. Then I pull up the exposure a little in post processing and raise shadows/darks.
4) No, I usually just stick with Photoshop and Lightroom (plus PTGui Pro for stitching the panos) for widefield, DSS and PixInsight take quite a bit of work to get the results you want and for widefield it's just not worth it.
