Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

Sign in to follow this  
JayPea

Budget guiding set up

Recommended Posts

Hi, thought I’d share my experience having a go at guiding on a budget. Not much for anyone to learn from it but it demonstrates it’s not complicated.

Last year, with astrophotography in mind, I bought a second hand HEQ5 Pro Synscan and a second hand Skywatcher Startravel 120 (it’s 600mm and also came with a few filters and bits). While you get some large and colourful stars in the images I’m more than happy with it to get my astrophotography eye in. Guiding seemed to be the next significant step to take.

I’m happy with the polar scope and moving around the sky using the hand controller. So my aim was to keep it simple, just connect camera to laptop and then to scope. Find my target, set it guiding and off I go.

My son had an old Celestron Travel Scope 70 telescope (F5.6 400mm and currently £55 on Amazon). So that was the guide scope sorted. It also had its own spotting scope. I then bought a Revelation 0.5x Focal Reducer for £25. So that gave me a more suitable shorter/wider and faster scope at roughly a 200mm/f3.

Second came the guide camera. After some searching I settled on an ELP Low Illumination USB Camera Module with the 3.75um Aptina AR0130 1.3MP colour sensor (I couldn’t find a mono version). It seemed a good compromise for £30. I just needed to mount it in a box (I used an ABS enclosure, RS part no. 502-332, 75 x 50 x 27mm) and then fabricate appropriate mounts to make it go into the scope eyepiece. I also added a heat sink and made sure to take any stress and loads off the sensor board.

At this point I was just going to use the IR cut filter from the lens that came with the sensor module. You can often just unscrew the ring off the front of the webcam lens and the bits fall out. You can reassembly with only the filter.

But it turned out in the bits I had with the used scope was a 1.25” Baader IR blocker filter. So I splashed out £15 on a Webcam to 1.25” Adapter that just screws into the M12 lens mount on the sensor board. That made it painless to screw the filter and reducer on there as well. Then it just slips into the guide scope eyepiece hole. It probably makes for a better aligned sensor than if I made a 1.25” tube assembly on the box myself.

Next was the connection from laptop to mount. I briefly looked at making something but in the end I got a ZWO USB-ST4 inline adapter for £35. In addition to being all done and in a nice small aluminium case it also included the USB and ST4 cables needed.

To mount the guide scope I used a thin length of metal plate to screw to the telescope rings. I had some 1/4 tripod to DSLR screws that appeared to have the right thread and had the benefit of the being hand screwed and with a coin slot making it easy to assembly.

Good solid guide scope mounts don’t seem compatible with a small budget so I used an old swiss arca type camera tripod base plate. I used a wing nut to keep it easy to assemble. I was thinking I could slightly rotate the guide scope left/right if I needed to point it somewhere different to the main target and I’d live with no up/down angle adjustment for now and see how it goes. I contemplated a ball head mount as I had one but it was suggested that it might make it too high and wobbly.

For the software I installed ASCOM, PHD2 and the ZWO USB-ST4 drivers. The USB camera had already installed itself OK and all the resolutions, modes and FPS appeared to show up OK in SharpCap.

Guiding connections were simple, plug camera USB to laptop and laptop USB to mountST4 via the inline ZWO box.  In PHD2 I choose Camera “Windows WDM-style webcam camera” and Mount “ZWO USBST4 (ASCOM)”.

It all appears to work OK although I had two minor self-inflicted issues that might be worth sharing.

On my first test I couldn’t find any stars. I had tested it during the day on “distant” objects (TV aerials), and pinholes in black card. They focused fine and it all looked OK. But unbeknown to me infinity focus was still enough away from a distant object so that I ran out of focus travel when I went for the stars at night. So without seeing stars I gave up. I tried again a few days later when the moon was out so I had something big to find and it showed it was out of focus even at full limit. But removing a locking ring off the focuser allowed an extra 2-3 mm of inward focus movement to see the stars OK. In fact I might get away with putting it back on now I know where it needs to be.

Once seeing a star was all sorted I tried PHD2 for the first time. Initially I couldn’t get it to work. Or to be more specific I didn’t give it time to work. I kept getting a message “Calibration this far from the celestial equator will be error-prone...”. I pointed the scope everywhere and the message kept appearing.

In the end I just ignored it and carried on. I took a couple of 2min test shots. Tracking was way way worse than without it! I put it down to something about this error and gave up for the night.

So I consulted my astronomy club and they suggested where I should point it. Tried again last Sunday and still the message appeared. Then I noticed the little white text updating in the bottom left corner of the PHD window and I realised it was trying to calibrate even though I had the message. I didn’t appreciate just how long it took to calibrate. After quite a few minutes the graph sprang into life and off it went tracking. My two bad images previously were likely just because I was exposing while it was finishing the calibration. Because of the “error message” I just assumed it hadn’t calibrated right.

I tried exposures up to 15 minutes pointing to Andromeda and the stars looked OK to my untrained eye. Set up is a Nikon D7100 DSLR on the 600mm telescope. That probably allows more exposure time than my light polluted town will take! It looks like it tracks keeping within the +/- 1 sec range. So I consider it a success so far.

Below is also the first 15min exposure (ISO 200 with Baader Contrast Booster filter). Not the best night for it, bright moon, thin wispy cloud and looking above a street light but I think it demonstrates the guiding is working.

Maybe it was not quite as cheap as I initially though it was going to be as I did splash out on the eyepiece mount and USB-ST4 adapters rather than make them (that was £50 of the £105 spent excluding the bits I already had around I used) but I think it was worth it for the extra quality and ease. Anyway I think it will keep me going for a while.

I now have no more excuses to avoid actually going out into the cold dark night and using the kit rather than staying inside and just surfing the web and tinkering in the garage instead.

 

John

PS sorry for the long read!

Budget Guiding.jpg

Budget Guiding-3.jpg

Budget Guiding-2.jpg

Budget Guiding-8.jpg

first guide.jpg

1st 15 min guide.jpg

  • Like 8

Share this post


Link to post
Share on other sites

An excellent and interesting write up. Nearly enough to make me take up imaging........only kidding ;)

Seriously, great stuff and an inspiration to those on a tight budget.

Share this post


Link to post
Share on other sites

A bit late posting this but below was my first proper try with the guiding. I fed deep sky stacker with all I took (30sec x 3, 120sec x 10 and a 253sec x 1 plus some flats) but I don't know what it ended up using. ISO 800 on a Nikon D7100. And tweaked to within an inch of it's life in Adobe Lightroom. Taken 10 o'clock  on a Sunday night on my front drive in Hertfordshire (Stevenage). I had a Baader contrast booster filter on and that appears to help loads compared to without it when I get uniform light orange images. I really should stay up past midnight as the lights do go off in our close then making it noticably darker. I also wish I'd bothered to centre the image as it came out way better than I expected for a trial shot!

 

D7100 ST120 Andromeda 1000.jpg

  • Like 3

Share this post


Link to post
Share on other sites

Came across your thread here and is a great read and inspiration. thanks for sparing and great image

Share this post


Link to post
Share on other sites
On 16/09/2016 at 19:55, JayPea said:

Hi, thought I’d share my experience having a go at guiding on a budget. Not much for anyone to learn from it but it demonstrates it’s not complicated.

Last year, with astrophotography in mind, I bought a second hand HEQ5 Pro Synscan and a second hand Skywatcher Startravel 120 (it’s 600mm and also came with a few filters and bits). While you get some large and colourful stars in the images I’m more than happy with it to get my astrophotography eye in. Guiding seemed to be the next significant step to take.

I’m happy with the polar scope and moving around the sky using the hand controller. So my aim was to keep it simple, just connect camera to laptop and then to scope. Find my target, set it guiding and off I go.

My son had an old Celestron Travel Scope 70 telescope (F5.6 400mm and currently £55 on Amazon). So that was the guide scope sorted. It also had its own spotting scope. I then bought a Revelation 0.5x Focal Reducer for £25. So that gave me a more suitable shorter/wider and faster scope at roughly a 200mm/f3.

Second came the guide camera. After some searching I settled on an ELP Low Illumination USB Camera Module with the 3.75um Aptina AR0130 1.3MP colour sensor (I couldn’t find a mono version). It seemed a good compromise for £30. I just needed to mount it in a box (I used an ABS enclosure, RS part no. 502-332, 75 x 50 x 27mm) and then fabricate appropriate mounts to make it go into the scope eyepiece. I also added a heat sink and made sure to take any stress and loads off the sensor board.

At this point I was just going to use the IR cut filter from the lens that came with the sensor module. You can often just unscrew the ring off the front of the webcam lens and the bits fall out. You can reassembly with only the filter.

 

But it turned out in the bits I had with the used scope was a 1.25” Baader IR blocker filter. So I splashed out £15 on a Webcam to 1.25” Adapter that just screws into the M12 lens mount on the sensor board. That made it painless to screw the filter and reducer on there as well. Then it just slips into the guide scope eyepiece hole. It probably makes for a better aligned sensor than if I made a 1.25” tube assembly on the box myself.

 

Next was the connection from laptop to mount. I briefly looked at making something but in the end I got a ZWO USB-ST4 inline adapter for £35. In addition to being all done and in a nice small aluminium case it also included the USB and ST4 cables needed.

 

To mount the guide scope I used a thin length of metal plate to screw to the telescope rings. I had some 1/4 tripod to DSLR screws that appeared to have the right thread and had the benefit of the being hand screwed and with a coin slot making it easy to assembly.

 

Good solid guide scope mounts don’t seem compatible with a small budget so I used an old swiss arca type camera tripod base plate. I used a wing nut to keep it easy to assemble. I was thinking I could slightly rotate the guide scope left/right if I needed to point it somewhere different to the main target and I’d live with no up/down angle adjustment for now and see how it goes. I contemplated a ball head mount as I had one but it was suggested that it might make it too high and wobbly.

 

For the software I installed ASCOM, PHD2 and the ZWO USB-ST4 drivers. The USB camera had already installed itself OK and all the resolutions, modes and FPS appeared to show up OK in SharpCap.

 

Guiding connections were simple, plug camera USB to laptop and laptop USB to mountST4 via the inline ZWO box.  In PHD2 I choose Camera “Windows WDM-style webcam camera” and Mount “ZWO USBST4 (ASCOM)”.

 

It all appears to work OK although I had two minor self-inflicted issues that might be worth sharing.

 

On my first test I couldn’t find any stars. I had tested it during the day on “distant” objects (TV aerials), and pinholes in black card. They focused fine and it all looked OK. But unbeknown to me infinity focus was still enough away from a distant object so that I ran out of focus travel when I went for the stars at night. So without seeing stars I gave up. I tried again a few days later when the moon was out so I had something big to find and it showed it was out of focus even at full limit. But removing a locking ring off the focuser allowed an extra 2-3 mm of inward focus movement to see the stars OK. In fact I might get away with putting it back on now I know where it needs to be.

 

Once seeing a star was all sorted I tried PHD2 for the first time. Initially I couldn’t get it to work. Or to be more specific I didn’t give it time to work. I kept getting a message “Calibration this far from the celestial equator will be error-prone...”. I pointed the scope everywhere and the message kept appearing.

 

In the end I just ignored it and carried on. I took a couple of 2min test shots. Tracking was way way worse than without it! I put it down to something about this error and gave up for the night.

 

So I consulted my astronomy club and they suggested where I should point it. Tried again last Sunday and still the message appeared. Then I noticed the little white text updating in the bottom left corner of the PHD window and I realised it was trying to calibrate even though I had the message. I didn’t appreciate just how long it took to calibrate. After quite a few minutes the graph sprang into life and off it went tracking. My two bad images previously were likely just because I was exposing while it was finishing the calibration. Because of the “error message” I just assumed it hadn’t calibrated right.

 

I tried exposures up to 15 minutes pointing to Andromeda and the stars looked OK to my untrained eye. Set up is a Nikon D7100 DSLR on the 600mm telescope. That probably allows more exposure time than my light polluted town will take! It looks like it tracks keeping within the +/- 1 sec range. So I consider it a success so far.

 

 

 

 

Below is also the first 15min exposure (ISO 200 with Baader Contrast Booster filter). Not the best night for it, bright moon, thin wispy cloud and looking above a street light but I think it demonstrates the guiding is working.

 

Maybe it was not quite as cheap as I initially though it was going to be as I did splash out on the eyepiece mount and USB-ST4 adapters rather than make them (that was £50 of the £105 spent excluding the bits I already had around I used) but I think it was worth it for the extra quality and ease. Anyway I think it will keep me going for a while.

 

I now have no more excuses to avoid actually going out into the cold dark night and using the kit rather than staying inside and just surfing the web and tinkering in the garage instead.

 

 

 

John

 

 

PS sorry for the long read!

Budget Guiding.jpg

Budget Guiding-3.jpg

Budget Guiding-2.jpg

Budget Guiding-8.jpg

first guide.jpg

1st 15 min guide.jpg

Thanks for this. I already built a similar project for mine but I gave up also when I could see the stars. I'm using a telephoto lens though 400mm but it is f6.3 together with my webcam. Thanks!

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.

  • Similar Content

    • By BUDA
      Hi All!

      I have guiding problem with the following guider setup: 9x50 finder + ZWO ASI 120mm mini + PHD2.
      The imaging scope is a 6' newtonian + canon dslr on a HEQ5, driven by a laptop via diy EQDIR cable.
      When the mount is set up and running correctly, polar aligned and all... I connect the guider camera
      and mount with phd2. All nice and easy, I run a calibration, then it starts to guide. All seems ok.

      Then I am starting to take pictures. The first seems OK, then the second have the star trails...
      I check phd2 and there is a message: the camera (ASI) did not take a picture for "xy" seconds so it is disconnected.
      Grrr.... I reconnect try to set up a longer period for "xy" in the settings as mentioned in the message.
      And all the same again and again. Whatever I add for connection timeout for the camera, it just reaches that
      and disconnect the camera.
      PHD + philips toucam has worked for me flowlessly. I changed to PHD2 because I gave myself a birthday present,
      the little ZWO camera. (and PHD did not recognize it)
      Do you have any idea what can be the problem? I will contact PHD2 help also, but maybe somebody had already
      the same problem and figured out how to overcome. I am almost sure I make some dumb mistake in the PHD2
      software settings, however I tried to change only what was needed.
    • By Tom Shinal
      Can Nebulosity and Ph.D operate simultaneously and share a single camera. Running Win 10.
       
    • By Forunke
      Ok, so this is a really annoying bug / problem that I have with my setup:
      From time to time, in non regular intervals the image my guiding cam (ZWO ASI120) send seems to get flipped / mirrored or looks like it's from a completely different patch of sky.
      When I'm paying attention to the guide images I can clearly see that the image seems to be flipped in some way.
      It only happens for 1 frame PHD send a warning ( No star found / Star lost Mass changed) and after that everything is fine again. My gear is all connected to a single USB3 Hub which then runs via powered USB3 cable to my Pc.
      I'm not binning and have the noise reduction off (though PHD might got hickups while processing) but it still happens. Sometimes there are minutes between two events sometimes it happens 5 times in a row.
      It also seems like it's only happening during guiding, I haven't seen it happen during calibration yet...
       
      I'm completely clueless what's happening or how to get rid of it, any help / idea is greatly appreciated.
    • By Cemers1
      Hi Guys, hoping someone can help me with the guiding issues Iv'e been having. First of all my setup is:
      Explore Scientific ED80 Triplet  Skywatcher EQ5 mount with synscan  Orion mini 50mm guide scope Altair GPCAM2 AR0130 Mono (as the guide camera) I did my polar alignment and 3-star alignment, which was spot on. So I set up the GPCAM2 and opened PHD2 where I selected "Altair Camera" and "On-Camera". It was all in focus, kept it on the default settings and I selected "auto select star", then it said I was guiding (I can hear the mount making small adjustments). A message popped up saying I needed to increase the max RA duration, then I needed to increase the max DEC duration, which I did gradually by 1000ms each time the message appeared. Still no progress.
      So I restarted the process with the max RA and DEC duration as 8000ms and it said I needed to eliminate the source of the problems.
      (I HAVE ATTACHED IMAGES OF THIS)
       
      I'm not sure why it not working and if I'm doing something wrong. But if someone knows where I'm going wrong, or has any advise it will be greatly appreciated!

      Oh and just let me know if you need any more info, because Iv'e probably missed something out. 
      Thanks again ?

    • By thomasv
      I've picked up a second hand Lightrack II recently, so was keen to test it. My plan was to use the guiding assistant in PHD to get a graph of the tracking performance, but initially the mount wouldn't move. After a search, I had to modify the guiding cable that came with the mount, as it was wired up 'the other way' to the one required for QHY5L. After that it calibrated fine and could run the test. Below is a 22min graph of the unguided performance, while it's not within the 2" peak-to-peak quoted, it's still pretty good. 
      Next I've tried it with a canon 300mm lens (unguided again), the picture is a crop of a 10min exposure, slightly eggy, but again pretty happy with that. 
       


×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.