Un linking Crosshairs in TheSkyX

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UN-LINKING SKY CHART FROM TELESCOPE CROSS HAIRS

ISSUE
When connected to a telescope mount, TheSkyX’s Sky Chart cannot seem to be pointed away from the telescope’s current position. For instance, using the Orientation > Look commands (e.g. Look South) briefly changes the Sky Chart, but then it immediately returns to where the telescope is pointed.
RESOLUTION
By default, TheSkyX will keep the telescope cross hairs centered on the Sky Chart. This behavior can be changed using the following procedure:

  1. Choose Telescope – Telescope Setup to open the Imaging System Setup window. (This can also be opened by clicking the Display – Telescope window’s Mount Setup button.)
  2. The Mount item should be selected in the Hardware Selection section at the left, so the right-hand portion of the window contains settings and preferences related to the mount.
  3. Look for the “Always keep telescope crosshairs visible on Sky Chart” setting, which is likely presently set to “Yes” or “Yes, centered”.
  4. Set this to “No”, then close the Imaging System Setup window.
  5. You should now be able to position the Sky Chart on any object or position desired, whilst connected to the mount. To return the Sky Chart to the mount’s position, use the Center Cross Hairs button on the Display – Telescope window.

Suspend Connection Button (TheSkyX Professional Edition Only)

If you’d prefer the Sky Chart to be centered on, or contain, the telescope cross hairs at most times, yet occasionally be able to position it elsewhere, then you may want to add a Suspend Connection button to a toolbar. (Customizing toolbars is described in the Toolbars section of the user guide.)
NOTE: This procedure requires TheSkyX Professional Edition

  1. In TheSkyX, press Ctrl+, (hold down the control key and then tap the comma key) or from the Edit menu (TheSkyX menu on Mac, Tools menu prior to version 10.5.0) choose the Preferences command.
  2. On the Preferences window’s Toolbars tab, click the Customize button (near the bottom of the window).
  3. Select a toolbar from the Toolbars list at upper-right of the window (the Telescope Toolbar is a logical candidate), or add a New one, if desired.
  4. Click anywhere within the Actions section on the left-hand side of the window, and then begin typing “suspend” to quickly locate the Suspend Button action.
  5. With the Suspend Button action highlighted, click the green —> (right arrow) button to add this to the selected toolbar.
  6. Use the green up and down buttons to move the action within the toolbar, if desired.
  7. Click the OK button to close the Customize Toolbar window, and then Close the Preferences window.

You should now have a Suspend Connection button on the chosen toolbar (you may also need to turn the toolbar on, which can be done from the context menu by right-clicking on either a currently visible toolbar, or the top-level menu region of TheSkyX’s window).

This is a toggle button: when selected, communications with the mount will be suspended; when deselected, communications will resume.

APPLIES TO:

TheSkyX Serious Astronomer Edition (partially)

TheSkyX Professional Edition

Unguided Imaging

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A lot of imagers (the majority seem to be portable) want to go unguided. This is easy enough with a short fl scope. Usually 450 to a bit less that 1000 mm in fl is where most start. There are a couple companies that make it reachable. Some imagers get it done the first try. You don’t hear from them as there is nothing wrong and they just image away but others (with the same equipment) have many issues.

The popular mounts for unguided are Software Bisque, Astro physics and 10 micron. All use modeling to accomplish unguided imaging. The mach 2 comes with absolute encoders (1100 and 1600 have them as an option). 10 micron has the same and you can order the Paramount MEII with encoders as well but the rest of the Bisque line up does not have absolute encoders (but work fine, the Taurus is an exception, the higher end models come with AE’s).

Once you get the modeling done (whole topic on its own as each manufacturers modeling setup is a bit different) you’re on to unguided but your stars are not round. They look good at 2 or 3 minutes but not at 5+ minutes, what to do. There are many things that can ruin an unguided image and you must check everything.

How long do you want to go? 

Unguided is not trivial even though some say it is.  Everything must be correct from the base to the seeing and even where you are pointing in the sky, refraction plays a part, high clouds, etc.

Make sure your PE corrects well (if an AE mount this is not applicable) and your model has few to no outliers which can be a result of some of the stuff below.

Even though every thing is tight sometimes it isn’t, you cant even feel it but any slight wobble can have a big effect at the arc second level.

Do you have thru the mount cables?  If not run correctly with a big enough loop and/or you try and jam as many as possible in that can be an issue.

Our permanent setups go 5 or so minutes unguided (Fl over 1500) when required other wise we guide (we have Paramount’s).  No thru the mount cables and the model is maxed for the horizon, 750 or so samples.  That is a high density model that lets ProTrack shine (RMS in the teens, polar alignment close enough, no reason to chase the numbers).  Some may say you don’t need that many samples (diminishing return) but it works for us where 150 or so was not what we wanted.

No CW hanging down at the end of the shaft (not a huge deal just like the weight close to the center). No riser blocks (if possible) and all cables sung but not tight to keep any tension down. 

High quality camera, FW, focuser, all ridged so nothing moves. Have found filters moving inside the FW, focuser tilting, rotator having the tiniest amount of play, etc. No visual backs with a camera nose piece or focuser held in by screw, this will usually never work, threaded, tight connections only. Your model should be able to show this and help you figure out what is going on.

The scope has been squared up (lots of messing around there (orthogonal) but its the little things that all add up.

Pour a yard of concrete all re bared up, bolt on a nice pier and add a rats nest at the top with 3 or 4 bolts and a plate to put your mount on.  It may be stable, or not, just another thing to look at but its hard to tell cause it feels tight.

Some examples

Here some set ups that may or may nor work well depending on how rigid they are, vibration suppression, repeatable flexure, etc.

Rat cage, works fine if set up correctly.
Rat cage, works fine if set up correctly.
Another example of a rat cage, many styles, not sure how these would work.
And another style, repeatable flexure?
Another cage with the pier bolted to a un isolated slab which may be connected to a house.

If any of the above setups are not stable or dont suppress vibration well or have flexure that is not repeatable (the models handle repeatable flexure fine), unguided (or guided sometimes) imaging can be a challenge. Of course there are imagers out there that have made all the above work just fine. These are just some points to get you thinking if you are having trouble getting round stars unguided.

The crazy stuff

It may sound like there is no way for any of the following to affect imaging but you must make sure if you have some of the following you can minimize them while imaging. These are just a few of the examples that were either learned by experience or someone else found and cured the problem on their setup. There are bound to be many more examples, keep an open mind.

Vibrations from roads, trucks hitting a bump in the road, a train half a mile away, dog running around, stereo in the house bumping, imaging from a deck or concrete that is not isolated (some pads are attached to the house), wind, wave on the shore, camera or attached computer fan or electronics, yours or the neighbors AC unit kicks on. Yes a lot of things make a difference and some have success even with some of these issues, each setup is different. Have seen a lot of good images from a deck but its not for everyone nor will everyone be successful from a deck.

Remember with unguided imaging, first make sure your raw PE is within spec, even with an AE mount you can still collect a raw log and see what the worm looks like. No jumps or anything unusual and you’re good. Dec is not a big deal, it never moves during unguided imaging unless you dither between images and technically your not imaging during the dither.

If you have a non AE mount make sure to train your PE. You will want under 2 arc seconds per pixel peak to peak so you’re under the (most) seeing and the PE is in the noise.

Once you are setup and imaging consistently unguided can be very nice but there is no ‘Push here’ to image button. You will more than likely have to put some time in to setup and trouble shooting to get things going well.

More fun

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More remote imaging fun, this time having nothing to do with remote imaging directly.  This does put a damper on the equipment working and having confidence that the domes close.  Gotta have power.

Of course this is a rare thing but fits in with the remote imaging theme of its always something.

This pole was installed in 2014, turns out it was incorrectly treated from the supplier and once in the ground slowly rotted till it snapped and fell. 

Asking around this is not the only one that had issues from the 2014 time period, seems the whole lot of em were incorrectly treated.   Luckily not a big deal just a bit of inconvenience, and more money.

TSX Bisque TCS Periodic error – The West check box

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When training Periodic Error Correction on a Paramount using the Bisque TSC – Periodic Error Correction – Compute PEC Curve tab, the West check box can be confusing.

For the West box if your mount is pointing East with the camera at 0° position angle (PA) and you flip the mount (with no rotation of the image train) to collect data West of the meridian the camera is now at 180° PA (upside down).  In this case you would check the West box when you save the fit data to the mount.

If you’re on the West side but the camera is at 0° PA (not upside down) you would not check the West box.

Basically 0° camera PA no West check box

180° camera PA check the West box, regardless of pier side.

The exception to this is if your system produces a mirror image, this is why checking camera PA with image link is important, it tells you if the image is mirrored or not.  If mirrored you basically reverse the above.

If you find the PEC has doubled the box is most likely the problem.  In this case you would just do the opposite and re save the log and grab another correction log to confirm.

Notes: for a raw PE tracking log the West box does not matter, only when you save to mount as the box is telling the control system if the curve is inverted or not.

Camera position angle is very important when collecting data for the PE curve, the camera must be at an angle of either 0° or 180° give or take a degree or so.

Ti Pro Dome shutter wind restraint mod

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This is a mod for the wind restraint system on the Ti Pro dome. The cables keep the middle shutter (which uses gravity only to stay on the dome unless in the fully closed position in which case it is locked in) in place during windy conditions during a close. I say during a close as you should not be opening the dome if its too windy. Sometimes wind does kick up during the night and the weather sensor (Boltwood, SkyAlert, AAG CloudWatcher) initiates the shut down command. The wind restraint does its job well but over the years we’ve had some issues as it wears.

What happens is as the shutter is opened and closed over many nights the cables eat in to the aluminum cable guides. Here is a image of the cable guides with cable doing their thing.

After a few hundred open / close cycles you can get wear on the guides from the cable dragging over them. There is no pressure as the cables are loose but the open / close action of the aluminum guides with the cable running through them as the shutter moves wears out a small channel in the guide as seen here.

If the cable happens to catch in the worn out channel on shutter close you can, depending on which shutter control you have, either snap a cable (new shutter control as of 2014) or pull (stretch) the close spring (right side front, looking in from home position) and rat nest the windlass screw on the old system. Here are before and after images of the spring on the old style windlass system.

Here is the close spring on the old windlass system in good condition.

This is a the result of the wind restraint catching and the close spring stretching.

On the new system the (one of two) cable snaps but the shutter still gets closed however on the old system once the spring is 4+ feet long (see image above) the windlass lose its tension and you get the rat nest with the shutter stuck about a foot from closed. Not good if you are remote and a long way away. Replacing the guides with regular maintenance works for the most part but we’ve been caught out with both shutter systems when it seemed we had a few months to go before guide replacement was required on the domes.

The mod is (at least for our domes) to use Polyurethane tubing and replace the guides with snug fit clamps. In our testing it will take many years for the cable to wear through the tubing if it ever does.

The clamps are 1/4″ ID and fit the tubing snugly. Going bigger does not seem to be an issue, 1/2″ or 5/8″ ID would be good as well (with the appropriate OD tubing). The clamps run a bit closer to the shutter lip but there is plenty of clearance and so far it is running smoothly.

This is 1/4″ OD x 5/32 ID Polyurethane tubing in white, very flexible and can handle -40 F ~ 160 F temps so weather should not be a problem.

Here is the shutter all together with the wind restraint mod.