wimvb

I think it's easy to take data quality out of the equation for any software evaluation. The IKI observatory has released several datasets of excellent quality. So, besides working on data collected by the OP, there is the possibility to also work on such a data set.

It does, but that got me thinking; @Stuart1971 you didn't mention a usb hub. My eqmod cable works fine when plugged into my Rock64 directly, but not when plugged into a (powered) usb hub. Otoh, my ASI174 and ASI294 cooled cameras don't work when plugged in directly, but do work when plugged into a powered usb hub. On a Raspberry Pi, everything works without the hub. ASI guide cameras always work without a hub. So maybe one last thing to try: a powered usb hub.

Wow, you pretty much tested everything. This is very strange. Otherwise I would have recommended to open a link in PuTTY with the mount directly connected to a windows machine, and send a command. But you'd already thought of that too.

You can increase dynamic range by stacking, sure. But that doesn’t mean that DR isn’t important. I’d rather start at 14 stops DR and work my way up, than at 8 stops and have to handle 64 times as many subs.

Very nice indeed. I would crop the image to avoid the bright star upper right.

Have you seen the "no eq" dso challenge in this forum?

From your signatue I see you use dslrs for imaging. A modern cooled cmos has more dynamic range than a dslr, and you don't need to use multiple exposure times. But you do need many subs to stack. In the end it's about total integration time, which depends on, among other things, local darkness (light pollution). I image from a relatively dark site (mag 20.5), and use a camera setting of low gain to maximise dynamic range, and exposure times that keep the stars from saturating, except the very brightest. My unstretched masters look completely black with just a few white dots where the bright stars are. But after stretching, I get colour in the stars and still enough detail to reveal faint galaxies over a billion light years away. To achieve this, I try to gather at least 10 hours of data on any one target, and use a work flow that I have optimised for those targets. And I avoid noise reduction as much as possible. Here's one example. https://www.astrobin.com/hh7zvu/

Isn't that googling your imaged object and looking at the equivalent Hubble image? As you wrote: "profoundly unsatisfying". Wise words. In the end it's not the plane that gets you to your destination, it's the pilot. And if the equivalent of that in AP ever changes, this hobby will lose much of its appeal.

I have compared prices; ZWO is the cheapest that works out of the box. Diy may be cheaper, but you still need to do the metalworking to get it attached to the scope. Btw, I just saw a video from Roboscope, where many if not most of the motorfocus devices were the ZWO eaf.

Very nice first image. If you want to take flats indoors, or directly after imaging session, check out LED panels as used for home lighting. You can combine these with a simple dimmer, and use a few layers of white fabric if still too bright. Just make sure you end up with exposure time not much lower than a second, or your camera shutter will cause strange effects. Next step is image processing, where your first priority should always be to achieve a pleasing colour balance.

Yes. (Enough said)

Great first image. Whatever you use for post processing, your first step should be to colour balance the image.

If you want everything remote controlled, you need: Eq mount with either usb or eqdir cable Telescope with motorised focuser Guide scope or OAG with guide camera, unless you bought that really expensive mount Imaging camera that is compatible with your imaging software (most dedicated astro cameras, as well as Canon, Nikon and other dslr cameras are) Control software based on either ASCOM (Windows) or INDI (linux) Computer near your setup to run the software Even then, you have to expect a few trips outside in order to take dust caps off, check for cable snag, verify that clouds have rolled in, etc. I've been imaging remotely for a few years now, and have a friend who has his scope in my obsy, and I can tell you from experience that remote imaging seldom is that. Just about a week ago, my friend had started up his gear after summer recess, and while imaging went fine, he attempted to park his scope with the camera at a point in space occupied by the mount. So, add a surveillance camera or web cam to the list.

I believe that @gorann doesn't use any calibration frames with this camera. And the general consensus seems to be that bias frames on cooled cmos cameras add more problems than they solve, because the bias signal varies between lights/darks and bias frames. Regarding the vertical lines, what exposure time did you use? Maybe just increasing the exposure will remove the banding.

I like to leave my calculator in its case when doing astrophotography, but sometimes it has its merits. What accuracy is needed in the altitude and azimuth bolts to get 10 arc seconds polar alignment? Suppose that the bolts press at a distance of 7 cm (70mm) from the central altitude or azimuth axis. (For an eq35, this may be an overestimate.) 10 arcsecond rotation at 70 mm, gives 0.0034 mm sideways movement; that's just shy of 3.5 microns, or 1/20th of the thickness of a human hair. Next, suppose the alt and az bolts have a 1 mm pitch (probably coarser). One would need to turn a bolt only 1.2 degrees, 1/300 of a turn, to move it 3.5 microns. With all the friction and stiction present in a coated, cast aluminium mount and base plate, I'd say that's just not possible to accomplish repeatedly. That's why I'm happy enough when I get the polar alignment error down to (less than) 5 arc minutes. Btw, if your mount's backlash doesn't allow guiding in DEC, you should really consider saving up for a bigger mount. The eq35 is based on the eq3, which lacks ball bearings in the ra and dec axes. In stead it has teflon washers to reduce friction, but those aren't as good as proper bearings. Nevertheless, spending a few evenings/nights getting dec backlash sorted is worthwhile. I got backlash down from 4000+ ms to below 700 ms (at a guiding rate of 0.5) in one night, and it really improved my guiding. But you have to do it in very small steps, and avoid binding at all cost.

Take a 30 s exposure with trails. View on screen and rotate the camera (eyeballing it). Take a new exposure with trails. View on screen and rotate camera. Repeat until satisfied. It takes about 3 such iterations, normally. All inall less than 5 minutes to ensure camera alignment. Well worth it, imo. If you like spending money, you can of course buy a camera rotator, but really not needed. Btw, I'm curious why you don't guide in DEC.

Yes, counter weight bars are safety hazards. At least you didn't lose polar alignment. 😉

I think (but could be wrong) that field rotation is more of a problem at high declination, and it's the only reason I can think of for rotation between subs. Also, if polar misalignment is 1 arc minute for each session, there can still be 2 arc minutes between two sessions (from -1 to +1). When I do polar alignment (using a routine that is similar to Sharpcap), and measure misalignment after I think I got it nailed, I can still get a value that is a few arcminutes off. Generally, I'm pleased when I get it lower than 5 arc minutes. But I always try to have my camera sensor aligned with RA. This makes framing between sessions easier.

Polar misalignment causes field rotation. Are you sure that your polar alignment was within 10 arcseconds? I can't manage such accuracy with my AZ-EQ6 on a pier. What polar misalignment does PHD report? The best wsy to avoid rotation, in my experience, is to align the sensor with RA. Take a 30 s exposure, and some 5 seconds in, start slewing RA+ at 1 x sidereal. Preview the exposure and turn your camera into the star trails. Repeat until the trails run along the frame's edge.

What took the longest time, fixing the stars or fixing Forest & son?

The mechanical construction of altitude and azimuth adjustments on most mounts don't allow for better than a few arc minutes in polar misalignment. Whenever I try to really zero in on PA, I notice that I adjust it to different positions without really improving. Two bolts pushing against a metal block are just not that accurate. In my experience (with a sw AZ-EQ6 mount), belt tension and backlash adjustments are more important for smooth guiding than accurate polar alignment. Btw, those low numbers for guide rate and aggression make sense for a smooth running mount. A "rougher" mount needs more force to get it moving. And a smooth mount will keep on moving (overshoots) if it gets too much force.

I wonder if that diagram is for fully corrected stars. The stars in the corners of your image show coma, a sign that they are not completely corrected.

Your sample rate was about 6.5"/pixel, which is undersampled. You can also tell by the star shapes in your image. All but the blown out stars look square, which is a sign of undersampling. Still, a very nice picture.

A full format camera has a sensor which is 36x24 mm, with a diagonal of about 44 mm. Only a very limited number of scopes/correctors can handle such a large field.

Does injury sustained during construction of an obsy count? A broken knee cap, surgery, and several months physical therapy.