Waves, part two

10/16/2025. Clear skies lured me into the backyard. Sloppy polar alignment, no guiding, no flats, no darks, not really obsessive focus. What could I really expect? Quite a bit, as it happens: yes, you can use the Wave 100i this casually with a fast, short 'scope. Note that while tracking is forgiving, decent alignment remains crucial for "goto" commands.

Tonight, I aimed the 400mm F2.8 about 6 degrees SE of Sadr and took 92, 10-second exposures. The stack took some clean-up, and I cropped the edges and corners because they really needed an actual rather than a virtual flat, but hey, for first-light it went pretty well. (Yes, I know the image resembles static from a 1960's TV as well as jewels on a velvet cloth; take your pick.)

92x10s, 400mm F2.8, R6, ISO 3200
Wave 100i unguided
BlurX etc
The yellow star at left is 19 Cyg; the bright blue star at upper left is 22 Cyg.

I used a hardwired USB connection (select Serial and COM5, go figure) in part because I could not reproduce my success with WiFi on the porch. I threw the kitchen sink at this casual stack to clean it up. I learned a bit about how to drive with SynScan Pro on the laptop, and since this is a useful mode, it might be worth investing in a SynScan controller so I could do without the computer in the field. I could also use a tablet if I can get that WiFi thing to work again, but the tactile, no-look convenience of a controller is tempting (keep an eye on eBay and AstroMart). In the meantime, do a decent polar alignment, keep a finder 'scope handy, and carry on. (BTW, what happens if I turn the computer off after starting a series of DSLR exposures? Does the mount just stop or does it carry on on its own? I'm not too sure where all the brains of this outfit are.)

10/18/2025. I've made jigs from small aluminum tubes aligned and J. B. Welded together. The design insight is the self-aligning geometry of side-by-side cylinders. Eh? Lay a couple of AA batteries side by side and roll one up against the other. Glue them in that position. Note that if you hold the paired batteries against a third cylinder (like a telescope tube), the longitudinal axies of the batteries and the third cylinder will all be aligned. The same geometry holds on the opposite side of the paired batteries. Place a fourth cylinder (like a finder telescope tube or a laser pointer) there, and it will also be held in alignment. Now, in place of AA batteries, picture aluminum tubing or conduit cut to appropriate lengths.

The first jig I made used three tubes. It had a specific design goal: the third tube provides a contact surface for the stalk of a finder already in hand. This is a little harder to describe since it works only with a particular style of stalk foot. That device seemed so elegant that I made a second jig, simpler, as described above using just two tubes. Voila, a self-aligning bracket for any optical devices housed in round tubes. It will help with aiming, and it will also serve as a pole finder for the Wave 100i, thanks to the mount's cylindrical design.

After "dry fitting" the new, smaller, jig against the 400mm lens barrel and using a laser-pointer to check for repeatability, I think its parallel tubes are too small (and maybe too short) to provide unambiguous alignment. So, iteration #3: I'm trying somewhat larger and longer tubes. Next would come "substantially larger" and then "much larger" and eventually will come "success." Experimental geometry -- what a concept.

And now... #4: I've skipped substantially larger and gone straight to much larger; the latest pair are a couple of inches in diameter. Set #3 might yet work, but I opted to make #4 just in case and for completeness's sake.

I was impressed with the promise and usefulness of a tool along these lines after my one night of star trials with strain-wave mount. A 9x50 erect image right-angle finder OTA (a tube of just over 1-inch radius) is enroute from China (so give it a few weeks to get here). There's plenty to learn in the meantime.

10/20/2025. On my second night under the stars, I used the largest (#4) collimating rings and a laser pointer to get closer to the pole. I think I am still not dead on, because a goto to Vega was a couple of degrees off the mark. Polaris is in the trees, so this is not a surprise. Likewise, a goto to M57 did not succeed. (There are steps I am missing in the polar alignement sequence. Youtube to the rescue soon.).

The previous configuration (serial, com5) worked right out of the box. I plugged the ASI120 guide camera into the USB3 port on the Toughbook, selected "Synscan" in the PHD2 menu to connect the mount, had the s/w select multiple guidestars, crossed my fingers and pressed "calibrate." Worked fine, albeit with a lot of Dec slop. Also, the steps are a little small. I am not inclined to optimize all that until I know that guiding works. Which it does. I began with 2-second guide exposures then went to 0.5 second. I increased RA aggressiveness to 90 and left dec at 100. Total guiding error is right at one arc second, so there is room to improve. I am doing a series of 10-second exposures somewhere near M57.

Uhm, it worked once. I refined polar alignment, built a one-star model using Vega (the missing step), adjusted some parms, and a goto landed square on M57. But now guiding is all to hell and in one axis only. I've tried the usual tricks (restart this, replug that, clear calibration, recalibrate...). I would think that tracking had simply not been reenabled, but I repeatedly got errors to the effect that the Synscan App was not found. ASCOM diagnositcs swear all is well. I got guiding in one axis only, which, for 10-second exposures at modest focal length, actually worked reasonably well:

M57, in situ
18x10s, 400mm F2.8, R6, ISO 3200, cropped.

One school of online though holds that a dedicated EQMOD cable is more reliable and less fiddly. I do not need problems I can solve for $20. An EQMOD cable will be here Friday (the driver to create and manage a virtual com port for it is in downloads/software/eqmod on G:).

Other dominoes related to this mount... An actual finder would be a great pleasure. The laser helps but my brilliant contraptions built around parallel cylinders does not align it as well as I wished. Go figure. Neither would the finder be well aligned, but... details). A 9x50 OTA to use with the new rings cannot arrive soon enough. I'll work out the alignment thing by and by.

I am still thinking a hard-wired controller might make life easier. Operating the computer, staring into a bright screen, finding and using the mouse pad, all while trying to nudge a starfield up, down, and sideways is more than a bit irritating. Let the computer guide and gather CCD data; use a more tactile device to do what I am accustomed to doing with the A-P hand controller on the heavier duty mount. But controllers are quite a bit more than $20, so before buying one, I want to give the app every chance, starting with decent polar alignment.

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