Question How do I connect everything for imaging ?

[Fish-Man]

Hi,

I am relatively new to astronomy as I had a long break, and have been re-astronomising (wow, is that a new word !?!) for about 6 months now.

I would like to start doing a bit of imaging, but am not sure where to start. I have searched this, (and other) forums and have an understanding of the terms and what to do, but I don't know where to start.

Luckily for me, I have inherited a box of bits from a friend of mines late father (who was into imaging), so I thought I would put it together and start out with his (my) bits.

So, here is a run-down of what's in the box:

9x50 guidescope with an SPC900 shoved up the tube.

GPUSB interface box from Shoestring Astronomy.

Manual filter wheel with 5 positions (unbranded).

B&W ICX414 CCD imaging box (is box the correct description?) from JTW Astronomy.

Leads - loads of them !

Adaptors, electrical and mechanical.

Filters etc.....

My visual set-up is a Vixen R200SS Newt with Telrad etc. on an HEQ-5 Pro mount.

Judging by its widespread use in forums, I will probably be using PHD for the guiding.

Now, my questions are:

1. What other software do I need ?

2. How does all the hardware fit together (a drawing of some sort would be great) ?

3. What software controls what bit of hardware ?

Thanks in advance for ANY help on this,

Paul

[x6gas]

Sounds like the 414 CCD imaging box (aka camera!) is the imaging cam so you should be able to connect that to the filter wheel and then couple that to the drawtube of the focuser on your scope - either via a screw thread or by using a nose piece that attaches to the filterwheel and then drops into the drawtube.

The 9 x 50 sounds like a finderguider. Can you simply replace your existing finder with that? The SPC990 connects to your computer running PHD and the GPUSB interface box connects from that PC, via an RJ-12 cable to guideport on your mount.

[Fish-Man]

Thanks for the info x6gas.

In the attachment is the drawing so far.

Is this correct?

Do I still need the handset connected?

How do I increase the magnification? Do I just put an EP between the filterwheel and the CCD?

Can I put a barlows in the focuser before the filterwheel?

What other software is necessary?

Any other modifications or additions needed ?

Regards,

[malc-c]

That looks right OK, with the GPUSB connected to the st4 port on the mount. If you want to do away with the handset you need an EQDirect cable and download EQASCOM and something like CdC planetarium software.

Yes you can use barlows to increase the size of the image on the cameras sensor

[kookoo_gr]

here is how you can use your equipment for imaging. for starters just as others said and according to the diagram you will attach the camera to the filter wheel and you will place them at the focuser with the help of an adaptor, preferably with a 2'' one. the camera will be connected to the laptop and use a capture software (don't forget the power supply for the camera). usually all the cameras have their own capture software at the provided cd but you can use others such as maximdl or nebulosity.

As for the guidescope, just like the diagram you will place it at the scope and connect the spc900nc camera to the laptop. In order to do guiding you will need phd since it's the most popular and easy guiding software.

When it comes to connecting the mount there are two ways of connecting it to the pc. either via the handset (if you have the synscan version and the handset's software version allows it) with the use of an extra cable that ends at a serial lead (you will need a usb to rs232 adaptor if your pc doesn't have a serial port) or with the use of the gpusb adaptor that will connect at the mount's handset port (the handset is obsolete for the remaining of the use). you will need the EQASCOM driver and EQMod software in order to use the mount via the pc along with a planetarium software (Stellarium, Cartes du Ciel, The sky, etc.)

Can you post a pic of the equipment?

[Fish-Man]

OK, getting the idea now, but a few more questions now:

1. Is "EQMOD ASCOM Driver" the same thing as EQASCOM or ASCOM ?

2. So which way is best, via handset, or via GPUSB ?

3. Stellarium, Cartes du Ciel, The sky - I have a copy of each of them. Any particular favourites out there ?

4. I am assuming my handset is capable, it is a SynScan v3.28 beta 21.

I have cables coming out of my ears, so if you mention it, I'll have one !

As requested, pictures of some of my equipment, and an update to the diagram.

Please feel free to tell me any alterations, or enhancements.

Thanks for the help guys.

Regards,

[chrisshillito]

1. Is "EQMOD ASCOM Driver" the same thing as EQASCOM or ASCOM ?

2. So which way is best, via handset, or via GPUSB ?

3. Stellarium, Cartes du Ciel, The sky - I have a copy of each of them. Any particular favourites out there ?

1. EQASCOM is the 'product name' of the EQMOD Projects ASCOM driver. It is commonly referred to as EQMOD although there are other applications available as part of the EQMOD project.

The ASCOM platform provides the framework by which ASCOM client applictions such as planetariums can access the services povided by ASCOM mount/dome/focuser/filter/camera drivers. The ASCOM initiative has its own website and support group and is separate from EQASCOM.

2. Either works just fine.

3. CDC is the most ASCOM friendly. Niether Stellarium nor The Sky support ASCOM 'out of the box' but there are third party apps/plugins that can do the necessary interfacing. Start with CDC and then progress to the others once you've got to grips with the basics of mount setup and control via ASCOM.

Chris.

[kookoo_gr]

if you have the rj11 to rs232 and an rs232 to usb (or an rs232 port at the pc) cable then use the handset (it is capable to connect it to a pc), otherwise go with the gpusb interface. as for the software i use cdc it's light for the pc and relatively easy to use

[malc-c]

I would still advocate making an EQDIR cable (or purchase one for around £40) and using that for communicating between the laptop and mount, and then set things up like this

[Fish-Man]

I can see him now, he's jumped his last hurdle and has appeared round the last corner. He's on the home straight now, and out in front. His worries are all behind him. Coming up to the line now.....

EQDIR ?

Ouch ! he's tripped and fallen.....

So, I've gone to the shoestring site and had a read of their product info/usage, but I still don't understand what the difference is between a GPUSB and an EQDIR. They appear to be doing exactly the same job, just using different cables and boxes.

Please can someone enlighten me ?

The thing is, I have a GPUSB box and cables, but I would have to go and buy the EQDIR.

Thanks,

[Fish-Man]

I can see him now, he's jumped his last hurdle and has appeared round the last corner. He's on the home straight now, and out in front. His worries are all behind him. Coming up to the line now.....

EQDIR ?

Ouch ! he's tripped and fallen.....

So, I've gone to the shoestring site and had a read of their product info/usage, but I still don't understand what the difference is between a GPUSB and an EQDIR. They appear to be doing exactly the same job, just using different cables and boxes.

Please can someone enlighten me ?

The thing is, I have a GPUSB box and cables, but I would have to go and buy the EQDIR.

Thanks,

EDIT:

There is also a HitecAstro EQDIR adapter on FLO:

First Light Optics - HitecAstro EQDIR adapter

Which is much cheaper - Is it the same thing ?

Cheers.

Latest diagram - any errors ?

[chrisshillito]

A few errors there I'm afraid.

Should you go the EQDIR route you would remove the synscan completely. The EQDIR connects to the mounts handcontroller port not the ST-4 port.

There are other options though: For instance you could run EQASCOM without an EQDIR by going via the synscan in PC direct mode (and you still get the option to drop the GPUSB should you wish and use ascom pulse guiding instead - but nothing forces you to do this)

As fars as the EQDIR/GPUSB is concerned they are two very separate things and certainly not interchangeable. The EQDIR is a communications interface that conditions the signaling voltages to the levels the mount expects to see on its handcontroller port. The GPUSB could be viewed as being an intelligent relay box that simply drives the ST-4 port inputs. Whilst the GPUSB simply guides the EQDIR allows your PC to take full control of all the mounts functions (goto, tracking, guiding, parking, PEC, alignment etc) via the EQASCOM driver.

EQDIR is a shoestring product name (used by others such as hitechastro) for what the EQMOD group call an EQDirect. There are quite a few vendors of these products to be found but they are also quite easy to make - full details are given on the EQMOD project website.

If you're at all interested in EQASCOM then I would advise you to take a good look around the EQMOD Project website - there are system connection diagrams there that illustrate the various options for PC based mount control.

Chris.

[kookoo_gr]

here is a diagram of the connections i suggest. after reading the manual of the gpusb module, it mentions that it is an interface that connects to the st4 port and you are able to send guide pulses from the pc to the mount's motors. if i am not mistaken from phd you will select the option from the mount menu (mount->on board, or on mount). but there is a second way to guide your mount.

you will do the connections as the diagram BUT you will omit the GPUSB interface and you will enter the guide pulses for the mount from the pc via the handset, it is called ASCOM guiding, it also saves you a usb port. you will just have to select form phd mount->ASCOM. with this method the guide cam sees the movement of the star and the pc sends a correction message via the handset to the mount. This way you can have better results at guiding since you can have better adjustment at the signals that the pc sends to the mount. for further detail you must read the EQMod manual.

As for the eqdir interface it is a module that replaces the handset of the mount and the need to use an rj11->rs232->usb cable. you just plug it in at the mount's handset port. it is more of value if you have the syntrek model (such as myself) but since you own the synscan model it is of no use to buy it.

[Fish-Man]

Hi,

Before I go on, I would just like to say thanks to everyone for their input, it has been really useful.

I think I have the hardware sorted now (see attached diag), but I am somewhat confused with the answers:

Originally Posted by chrisshillito

"EQDIR allows your PC to take full control of all the mounts functions (goto, tracking, guiding, parking, PEC, alignment etc) via the EQASCOM driver."

Originally Posted by kookoo_gr

"As for the eqdir interface it is a module that replaces the handset of the mount...

...it is more of value if you have the syntrek model (such as myself) but since you own the synscan model it is of no use to buy it."

So, it's 1 - 1 for EQDIR !

Anyway, narrowing down my options, I think the GPUSB is out (I'll sell that as I can't see me using it ever now).

I don't think that going via the handset is a good idea, as I can get more, better, and accurate positioning etc. from CdC.

So I am left with buying/making an EQDIR, or buying/making cables and going the EQDIRECT route.

Apart from cable length restrictions and costs, are there any advantages for either ?

Regards,

[kookoo_gr]

a few remarks as i think you have mixed thing up a bit.

1. the handset provides you an interface to connect to the pc (see my diagram) so you don't need to buy an eqdir module. once you have connected the mount to the pc the handset is "deactivated". whether you use the eqdir module or the handset to connect to the pc you will have the same accuracy, goto etc. it all depends on the polar alignment, balancing of your equipment.

2. at your diagram there are a few errors. first of all the rs232 diamond you drew connects to the handset, period. if you connect the diamond shape directly at the mount's handset port then you will blow the board since the mount can't handle rs232 signals, they need to be converted to TTL signals and that's where the handset comes into play. as for the gpusb module i would remove the line that connects it to the handset since you will be using it (the gpusb module that is) for connecting it to the autoguider port

[chrisshillito]

I don't think that going via the handset is a good idea, as I can get more, better, and accurate positioning etc. from CdC.

So I am left with buying/making an EQDIR, or buying/making cables and going the EQDIRECT route.

Apart from cable length restrictions and costs, are there any advantages for either ?

Regards,

I think you are still a little confused by the terminology.

An EQDIR is just a commercial product name for an EQDIRECT interface device.

PC-DIRECT is an operating mode into which the handset can be placed. When in PC-DIRECT mode the synscan just goes transparent and passes messages it receives from a PC directly to the mount. The EQMOD ASCOM driver (EQASCOM) is designed to work with a direct connection to the mount and this can be achieved either by using an EQDIRECT device or by operating the synscan in PC-DIRECT mode.

Now it is important to understand that the EQMOD devolopers (I am one) have only ever designed the EQASCOM code to operate via an EQDIRECT connection and can make no guarentees over the system reliabilty/robustness if using a synscan in PC-DIRECT mode. So if you want to used EQASCOM as it has been designed to be used then loose the handset altogether and use an EQDIRECT. This said, why not initially evaluate EQASCOM by using the synscan in PC-DIRECT and then later you can decide if you want to switch over to the EQDIRECT interface.

Irrespective of how you interface EQASCOM to your mount (PC-DIRECT oe EQDIRECT) the goto accuracy, tracking accuracy will be the same.

Chris.

[Fish-Man]

Hi Guys,

whether you use the eqdir module or the handset to connect to the pc you will have the same accuracy

Irrespective of how you interface EQASCOM to your mount (PC-DIRECT oe EQDIRECT) the goto accuracy, tracking accuracy will be the same.

But, from the EQMOD Project website, it says:

"When using EQASCOM we connect directly to the mount and bypass the synscan control algorithms. This has allowed us to write our own advanced alignment, tracking, PEC and limit proteciton algorithms that provide greater functionality than provided by the synscan itself."

So, what have I mixed up this time ?

Thanks again for your help and advice.

Regards,

Paul

[kookoo_gr]

EQASCOM: a "driver" that allows to connect the mount to the pc and operate it via EQMod. you can control the mount with EQASCOM or any other software that needs EQASCOM

EQMod: a software that allows the operation of a mount. you have goto, manual operation, tracking modes, polar alignment tool, mount parking/unparking positions and guiding options along with PEC.

both of these bypass the operating system of the handcontroller, again the handcolntroller has a built in interface that allows the connection of your mount to the pc

EQIDIR (or any other name you may come across it): an interface that allows the connection of the mount to the pc. if you don't have a synscan handcontroller or its version doesn't allow it you remove the handcontroller and connect your mount to the pc with its help.

[malc-c]

Paul,

The handset is in essence a small computer that has an object database built in. When using it to control the mount you run through the initial set up procedure and it then uses it's own algorithms to work out where it's pointing, any cone errors, PEC etc etc. The handset has the option to set it to PC-DIRECT mode, and then it acts as a simple pass through box to the mount. All the PEC, alignment, cone error, tracking etc is done from the PC via software. The PC-DIRECT mode hasn't been documented, so what processes are done between the PC and mount by the handset is to a degree unknown.

The EQMOD developers came up with the EQ-DIRECT lead to communicate between the mount and PC, and the two go hand in hand. The software offers far more than the handset, plus when using other software such as PHD the whole ASCOM platform interfaces well.

As explained the GPUSB is basically a switching box. When guiding, its does the same thing as manually pressing the direction keys on the handset does, thus moving the mount NSEW. With guiding through EQMOD using ASCOM platform the control is a lot more refined. If you look at my sketch above and compare its simplicity to your own, I think you are over complicating matters.

[chrisshillito]

EQASCOM: a "driver" that allows to connect the mount to the pc and operate it via EQMod. you can control the mount with EQASCOM or any other software that needs EQASCOM

EQMod: a software that allows the operation of a mount. you have goto, manual operation, tracking modes, polar alignment tool, mount parking/unparking positions and guiding options along with PEC.

both of these bypass the operating system of the handcontroller, again the handcolntroller has a built in interface that allows the connection of your mount to the pc

EQIDIR (or any other name you may come across it): an interface that allows the connection of the mount to the pc. if you don't have a synscan handcontroller or its version doesn't allow it you remove the handcontroller and connect your mount to the pc with its help.

The EQMOD Project's ASCOM driver called is EQASCOM, many folks refer to this as simply EQMOD. EQMOD is EQASCOM and it makes no sense to talk of EQASCOM being a driver that allows control by EQMOD.

The EQDIRECT (or what ever your preferred vendor happens to call it) is the only correct means of interfacing EQASCOM to the mount irrespective of synscan version available. Use PC-DIRECT and you are operating EQASCOM out of spec (and are operating the synscan itself in a totally undocumented mode). This said, many folks do happily use PC-DIRECT in combination with EQASCOM and that's fine by me, it is their choice to ignor the advice the developers give.

Chris.

[chrisshillito]

Hi Guys,

But, from the EQMOD Project website, it says:

"When using EQASCOM we connect directly to the mount and bypass the synscan control algorithms. This has allowed us to write our own advanced alignment, tracking, PEC and limit proteciton algorithms that provide greater functionality than provided by the synscan itself."

So, what have I mixed up this time ?

Thanks again for your help and advice.

Regards,

Paul

Hi Paul,

EQASCOM requires direct contol of the mount and uses a communications protocol that talks direct to the mount's motor controllers. When the synscan is placed in PC-DIRECT mode it is suposedly no longer in control of the mount but instead acts dumb and just transparently passes messages between pc and mount. On the face of it this therefore provides the direct connection that EQASCOM requires. In reality the synscan can still command the mount if the user presses the direction buttons and this is one are of concern from an EQASCOM perspective.

So whether using and EQDIRECT, or a synscan in PC-DIRECT mode, it is the EQASCOM control algorithms that will determine the goto, tracking, pec etc.

Chris.

[Fish-Man]

I think you are over complicating matters.

's funny you should say that - I seem to go overboard on the understanding of ANY subject, instead of just dealing with what I just need to know.

The bad news is, I'm probably not going to change now.

I have decided to put my usual avatar up - I suppose it says it all really.

As for the problem at hand, it's all slowly falling into place now, and I am really grateful that you have stuck with me on this. I know I can seem a bit dim at times, but trust me, I really am quite well schooled, even though it doesn't show !

I shall do a bit more reading and construction.

Regards,

Paul

[malc-c]

To be honest you can simplify things a lot more but using an active cable and a USB hub at the mount. Then you only have one USB cable running back to the PC

[Fish-Man]

To be honest you can simplify things a lot more but using an active cable and a USB hub at the mount. Then you only have one USB cable running back to the PC

As it happens, that is what I was going to do. I have a powered 7 port USB hub, so I should be OK with all my USB needs.

Just to finally put it to bed, I can get rid of my GPUSB box now, can't I ?

Thanks,

Paul

[chrisshillito]

To be honest you can simplify things a lot more but using an active cable and a USB hub at the mount. Then you only have one USB cable running back to the PC

In my experience it is best to avoid routing cameras through hubs as they can be quite demanding in terms of power and bandwidth. Far better to take the cameras back to separate PC ports and, if it helps, hang the other bits and pieces (eqdirect, gamepad, focuser, gps etc.) off a powered hub.

Chris.