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Autoguiding without GoTo


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Hi. I understand that it’s possible to autoguide with a non GoTo telescope. Does anyone have experience of this? I have a HEQ5, RA and DEC tracking mount with a Skywatcher 200p telescope. I would like to add a astrocam to the 9x50 finder scope and start taking nebula images with a DSLR camera. I know this is pretty basic but it’s a start. Can anyone advise if this setup is workable and if so, what software would I need that would guide the astrocam? Also, would it just plug straight into a laptop?  Additionally, I also have the scope connected to the laptop with a GPUSB box with ASCOM driver and EQMOD software. As a beginner I have attempted to connect to Cartes Du Ciel but it does not show my telescope position when I move the scope, even though I understand that the software does not drive the scope, as I don’t have GoTo. Maybe this is not compatible with my simple setup? If this is not going to work out, then is there another way to use as an imager? As suggested before, I know i need to manually get the object in view, but once that is done will autoguiding keep it there? Quite a lot of questions I know but please accept my lack of knowledge? I think the more  I read, the more I am confused? Thank you for looking at my post. Kind regards.

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GoTo and autoguidng are two entirely unconnected things so you can autoguide a non GoTo mount, certainly. GoTo does make imaging much easier but it isn't compulsory.

There are two main ways to autoguide, both using the free PHD 2 software. The original way, which I use, involves plugging in a USB connection between guide camera and PHD on the PC and also connecting the camera to the mount using an ST4 cable. (The term ST4 cable is not strictly correct but the term is universally used and understood. It looks like a phone cable but beware, it's not wired in the same order. Buy it from an astronomy supplier.)

I don't know if your camera is known by default to PHD2 but, if it is, you choose that model and select 'On Camera' in PHD. You'll find plenty of How To videos via Google.

The other method involves using pulse guiding in EQ Mod. I don't use that method so will let others explain it.

Have fun,

Olly

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Thanks Olly for replying. I’m happy that I am there or thereabouts. The camera I intend on buying is a BRESSER MikrOkular Full HD Eyepiece Camera. (I know. It’s probably the cheapest astrocam in the world). It does not have a ST4 port but I have seen YouTube videos where astrophotographers prefer not to use their ST4 ports and so I cannot connect to the mount. That is why I was wondering if the camera is just directly plugged into laptop? My mount does not have a ST4 port either, only a socket for handset input. (Not sure if this a ST4 port). I will watch some YouTube videos on PHD as I am not sure  how the telescope interacts with the software and what, or how, it all works. Thanks again for your advice.

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You need some way of connecting the computer to your mount for autoguiding to work. The two most common ways are:

  1. connect the camera to computer via USB and connect camera to mount with ST4
  2. connect camera to computer via USB and connect mount to computer via another USB

Method 2 is preferred because it allows more functionality but is not an option for you.

As far as I know you would have to modify your hand controller to provide an ST4 connection for option 1.

Now even if you could get that part working you need to be able to send commands from your computer to the mount. For that you need a device like an AstroEQ which plugs into a USB port and converts to ST4. I think you'd be better off getting a camera with an ST4 port and/or a mount with at least ST4 connection. Unless you are into DIY electronics and programming.

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Does the handset has a ST4 port guide port? If it's red, your're OK. If it's black, you'll need a red one or to get the soldering iron out!  That's probably the easiest route - as far as I know, there's no way to connect the handset/mount you have to a PC directly.

Is there any reason to choose that camera specifically? For example, the ZWO planetary cams all have guide ports and are well reviewed for planetary imaging too.

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The handset plugs into the mount where another cable comes out of the handset and is wired to GPUSB which plugs into the computer via USB. Would this be suitable for connecting the mount via ASCOM? Then the guiding camera would then be directly connected, via USB to the computer. Thanks

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You'll also need to install PHD2 to do your autoguiding: https://openphdguiding.org/

You'll need to choose GPUSB as your mount in PHD2 then you will be able to guide. But your mount cannot report its position so CdC and similar tools cannot show where it is. You need a goto mount for that.

Check that there is an ASCOM driver for your camera. I had a quick look and found no mention of one. You'll need that to connect it to PHD2. Or get a caera that has an ASCOM driver or is PHD2 compatible. It is remotely possible that the WDM driver in PHD2 will recognise it.

For navigating the sky you either need to learn how to star hop or learn about plate solving. You might want to get the basics going first

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On 24/01/2021 at 10:56, kens said:

You need some way of connecting the computer to your mount for autoguiding to work. The two most common ways are:

  1. connect the camera to computer via USB and connect camera to mount with ST4
  2. connect camera to computer via USB and connect mount to computer via another USB

Method 2 is preferred because it allows more functionality but is not an option for you.

As far as I know you would have to modify your hand controller to provide an ST4 connection for option 1.

Now even if you could get that part working you need to be able to send commands from your computer to the mount. For that you need a device like an AstroEQ which plugs into a USB port and converts to ST4. I think you'd be better off getting a camera with an ST4 port and/or a mount with at least ST4 connection. Unless you are into DIY electronics 

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On further study, if I cut the plug off the crossover adapter and wire it into the handset this would give me a ST4 port. I could then buy a ST4 to usb cable to connect to PC.
I am confused as to what the GPUSB connection to PC does? I thought it did the same thing? Would any of this work? Thanks, in advance for any help.

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13 minutes ago, astro postman said:

On further study, if I cut the plug off the crossover adapter and wire it into the handset this would give me a ST4 port. I could then buy a ST4 to usb cable to connect to PC.
I am confused as to what the GPUSB connection to PC does? I thought it did the same thing? Would any of this work? Thanks, in advance for any help.

This may explain  more for your current set up

 

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18 minutes ago, astro postman said:

On further study, if I cut the plug off the crossover adapter and wire it into the handset this would give me a ST4 port. I could then buy a ST4 to usb cable to connect to PC.
I am confused as to what the GPUSB connection to PC does? I thought it did the same thing? Would any of this work? Thanks, in advance for any help.

To do what your saying above would need a dedicated Guide cam with st4 port

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I understand that you can connect camera directly to PC?

What is the GPUSB for? is it a direct replacement for an ST4 Port? Or do I still need a ST4 Port to connect HC to PC?

One last thing, I do not have separate leads exiting the HC for RA and DEC. It is a telephone jack that fits directly in the mount. I guess this is not a problem just a later adaptation from EQ3 mount?

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My apologies just re-read your first post I was thinking eq3-2 for some reason, gpusb is your interface to connect laptop to autoguide port on the mount I would think for phd2 to do guide corrections. I may well be wrong I'm pretty new to fiddling with mounts myself.

Edited by Paul779
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Paul 779. Thanks for your help. The GPUSB is wired into the handset which is connected to the mount. It doesn’t have a ST4 port. I think I can connect the camera, which will be fitted to 9x50 finder scope, directly into the PC. There is something I just can’t get my head around here?😂

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9 hours ago, astro postman said:

I got this with it as well. I guess it’s redundant? The black ends takes the handset. The other end is a larger and I guess fits into a ST4 port but I don’t have a socket on the mount for it. Thanks

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I'm not sure what this device is. Based on the label I suspect it is an ethernet crossover which is generally unnecessary these days.

5 hours ago, astro postman said:

On further study, if I cut the plug off the crossover adapter and wire it into the handset this would give me a ST4 port. I could then buy a ST4 to usb cable to connect to PC.
I am confused as to what the GPUSB connection to PC does? I thought it did the same thing? Would any of this work? Thanks, in advance for any help.

Just because the plugs are the same does not mean they are electrically/electronically compatible. I'd caution against trying that.

2 hours ago, astro postman said:

I understand that you can connect camera directly to PC?

What is the GPUSB for? is it a direct replacement for an ST4 Port? Or do I still need a ST4 Port to connect HC to PC?

One last thing, I do not have separate leads exiting the HC for RA and DEC. It is a telephone jack that fits directly in the mount. I guess this is not a problem just a later adaptation from EQ3 mount?

You can connect the camera directly to the PC but for it to be usable by PHD2 you need an ASCOM driver for it or hope that the built in drivers in PHD2 can talk to it. Check with the supplier before buying.

The GPUSB converts USB signals to ST4 signals, just like a ST4 camera would. ST4 signals simulate pressing the button on a hand controller. There are separate wires for N/S/E/W. N/S = Dec and E/W = RA. So the mod to you handset has connected the ST4 wires to the outputs of the button on your handset which then controls the mount.

 

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@kens thanks for chiming in there my knowledge on this is very limited at the mo, also if I'm not mistaken the gpusb shouldn't be wired in to anything I thought it was a plug and play device so to speak male usb one end and ST4 port on the box

Edited by Paul779
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2 hours ago, astro postman said:

Ken’s. It sounds like the mount is sorted? I just need to get the right camera?

Looks that way.

2 hours ago, Paul779 said:

@kens thanks for chiming in there my knowledge on this is very limited at the mo, also if I'm not mistaken the gpusb shouldn't be wired in to anything I thought it was a plug and play device so to speak male usb one end and ST4 port on the box

Normally that is the case and the GPUSB would plug into the mount guiding port. In this case it looks like the handset has been modified to achieve the same outcome.

2 hours ago, astro postman said:

If I am on target for setting up the hardware. The next problem will be the software. With Cartes du Ciel  which connection driver do I use? 

Cartes du Ciel wont work with your mount. It needs a Goto mount to show where the mount is pointing and to move it around. If you want to know where the mount is pointing you would need to plate solve. To move the mount you need to do it by hand or via the handset. With the handset the highest speed is 16x sidereal which would take over 20 minutes to slew 90 degrees.

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Thanks for the reply. Once I’m on the target manually, and locked on, I guess I don’t need to worry about the slow slewing? Do you mean the only way that I will know where I am is by the setting circles, or is there another more visual way?

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PHD2 only knows about guiding. I don't use APT so can't comment on that but in general software only knows what the mount tells it.

Aside from setting circles (which are generally not very accurate) there is plate solving where you take a photo and the plate solving software works out from that where you are pointing.  In your setup, once you know where you are pointing adn where your target is you can use the hand controller to move to the target. There is some calcuation involved to work out how long you need to press the buttons for. But you can plate solve progressively till you get onto the target.

A very manual way is to use a planetarium (e.g CdC or Stellarium) and your finder scope to star hop from one prominent star to another till you get to your target. 

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