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Idiot's/Numptie's/Dummie's Guide To Guiding, Etc...


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I've got myself a SW EQ5 Deluxe mount with the Enhanced Dual Axis Motor Drives. I like occasionally to do smartphone imaging through the eyepiece, using a smartphone holder.  I also have a spare SW 9x50 straight through finderscope that I could use for a guide scope.  The 'dumb' handset of the Enhanced kit has a ST4 port on it.

With all this in mind, is there a idiot's/numptie's/dummie's guide to guiding, etc. for a newbie to guiding, etc?

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Thing is "guiding" to most people these days means using a guide camera and software that runs on a computer which can also control the mount.  I think this was pointed out when you were considering which motorising option to go for, as the synscan unit makes computer control a lot easier.  With the controller you have the only real option without having to modify the handset (and thus void your warranty) is to use an all in one autoguider such as Skywatcher SynGuider but at a pound shy of £290 it isn't cheap.

Before the days of computer control and guide cameras manual guiding was done.  This involved using a guide scope with an illuminated eyepiece that formed a cross-hair, and by using small XY knobs could move the two lines so they intersected over a bright star in the field of view.  You then used the NSWE (or Up Down Left Right) buttons on the handset to make small corrections manually to keep the star under the intersected lines.

However, guiding is really suitable for long exposures, and given you intend to use a mobile phone is probably not worth it.  I would suggest your first target is the moon, ideally when in any phase other than full.  Polar align the mount (doesn't need to be exact) and get the Moon in the eyepiece and set the drive to LUNAR.  Then use the movie function to record a video of the moon for several minutes, ensuring the projected image is as sharply focused as possible.  Then you can use software to take the movie and split it into individual frames and then stack the good ones to form a detailed image with lots of data.  You could try this on some of the larger planets, but Jupiter and Saturn and not as well placed as they were in the summer time.  You might (depending on the capabilities of your phone) be able to image the Orion nebular (set the drive to SIDERIAL ) if your camera can take long timed single exposures of 30 - 60 seconds (any more and you are into guiding territory).  Take 20 to 50 exposures one after another, then just before you break down for the night, and without moving the camera, place the cover over the front of the scope and take 20- 30 exposures of the same length (called darks).  You can then stack all these images in deep sky stacker.  Providing the polar alignment was good and there was little or no trailing then you might just end up with a half decent image.  For anything more, IMO you are going to need to invest in a rig that is better suited to imaging, which involves a decent camera for prime focus photography, and a means of guiding the scope.

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11 minutes ago, malc-c said:

Thing is "guiding" to most people these days means using a guide camera and software that runs on a computer which can also control the mount.  I think this was pointed out when you were considering which motorising option to go for, as the synscan unit makes computer control a lot easier.  With the controller you have the only real option without having to modify the handset (and thus void your warranty) is to use an all in one autoguider such as Skywatcher SynGuider but at a pound shy of £290 it isn't cheap.

Before the days of computer control and guide cameras manual guiding was done.  This involved using a guide scope with an illuminated eyepiece that formed a cross-hair, and by using small XY knobs could move the two lines so they intersected over a bright star in the field of view.  You then used the NSWE (or Up Down Left Right) buttons on the handset to make small corrections manually to keep the star under the intersected lines.

However, guiding is really suitable for long exposures, and given you intend to use a mobile phone is probably not worth it.  I would suggest your first target is the moon, ideally when in any phase other than full.  Polar align the mount (doesn't need to be exact) and get the Moon in the eyepiece and set the drive to LUNAR.  Then use the movie function to record a video of the moon for several minutes, ensuring the projected image is as sharply focused as possible.  Then you can use software to take the movie and split it into individual frames and then stack the good ones to form a detailed image with lots of data.  You could try this on some of the larger planets, but Jupiter and Saturn and not as well placed as they were in the summer time.  You might (depending on the capabilities of your phone) be able to image the Orion nebular (set the drive to SIDERIAL ) if your camera can take long timed single exposures of 30 - 60 seconds (any more and you are into guiding territory).  Take 20 to 50 exposures one after another, then just before you break down for the night, and without moving the camera, place the cover over the front of the scope and take 20- 30 exposures of the same length (called darks).  You can then stack all these images in deep sky stacker.  Providing the polar alignment was good and there was little or no trailing then you might just end up with a half decent image.  For anything more, IMO you are going to need to invest in a rig that is better suited to imaging, which involves a decent camera for prime focus photography, and a means of guiding the scope.

Correct me if I'm wrong, but once you've set up the guide scope and camera on a target star, then using PHD2 should keep the guide scope aligned by sending small "nudges" through the ST4 port to the mount? 🤔

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1 minute ago, Ian McCallum said:

Correct me if I'm wrong, but once you've set up the guide scope and camera on a target star, then using PHD2 should keep the guide scope aligned by sending small "nudges" through the ST4 port to the mount? 🤔

The ST4 port on the handset is for direct connection from the guidecamera's ST4 port using an ST4 cable.  You need a USB connection between the guide camera and the PC running PHD2 with PHD2 set to "on camera" for this to function.  The alternative is to purchase a USB > ST4 adapter  such as this one  ( for years the GPUSB "shoestring" adapter was popular) which you can fit between the computer and your controller, and then use any USB camera as a guide camera provided it is ASCOM compliant.  This way, PHD sends the corrections to the mount via USB, and the adapter mimics the pressing of the NSWE buttons to make corrections.

ST4 guiding is not like pulse guiding via a synscan unit.  All an ST4 port does is basically parallel wires the push buttons on the handset, and pins in the port get shorted by the ST4 device thus mimicking the pressing of the buttons.  

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