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.

KevS

Anybody Playing Tonight?

Recommended Posts

The subs are almost back to where they were now.

433357840_Heartg300_Light_OIII_180_secs_2020-01-20T22-02-15_056.png.8504d40f8f8c3132f20a7d3faf96a5a9.png

  • Like 3

Share this post


Link to post
Share on other sites

Cloud stopped play.

But there are clear skies in the distance which hopefully are coming our way.

Carole 

  • Like 2

Share this post


Link to post
Share on other sites

Seems what I thought was cloud was dew on the lens.  Guess which nitwit forgot to check the dew heater was on!!!   Lost about an hour!  At least  it wasn't the rest of the night thanks to James, mentioning his dew problem.  Now have 35 subs - 1¾  hours.

Edited by Gina
  • Like 2

Share this post


Link to post
Share on other sites

About fifteen mins or so of this run left, then I think I'll close up the 'scope and maybe do a bit of visual. I can't be up too late as the contractors are still at work on the obsy platform. They have only done the retaining wall, and that's about 3 tonnes of stone and mortar, they still have to pour the concrete yet.

  • Like 1

Share this post


Link to post
Share on other sites

The sky is holding up pretty well here so far (touch wood). I've just popped out for a few minutes to let my eyes dark adapt and the sky is milky towards the horizon, which tells its own story, but there is a pretty decent MW overhead and I can see all 7 primary stars in Ursa Minor overhead, which is fair test of conditions. Guiding still bobbling along nicely at sub 0.5" total RMS - what's not to like 😎

  • Like 2

Share this post


Link to post
Share on other sites

Not without issues here either. After a good 2 hours early on with M45, the switch back to M42 has been painful. The mount refused to sync after a meridian flip. Been driving me crackers after really impressing me up to now. Been going through the EQMod settings. Noticed my longitude was set to East when I'm West! Eventually found out I'd set Longitude in NINA as a positive value! I've lost about an hour of imaging time but seem to have got it going again. Just means I'm staying up a bit later I guess!

  • Sad 2

Share this post


Link to post
Share on other sites

The new quad is doing its job well enough. As long as focus is nailed down it works well I the corners.

Screenshot_20200120-225121_VNC Viewer.jpg

  • Like 4

Share this post


Link to post
Share on other sites

It's been a brilliant few nights!

Getting such a load of data seems to take some of the pressure off and allows a bit of experimentation.

I've just used a feature in CCDCiel for the first time, and it has worked brilliantly.  After doing the meridian flip I loaded up the last sub and told it to move the mount to the centre of the image.  It platesolved, then slewed, and platesolved again.  After a minute or two it told me that it was 0.47 arcminutes away from target. 

I like this feature a lot!

Touch wood, I seem to have got the autoguiding working properly again, although I have no idea what was causing the problems.  I have learned what the difference is between 0.7" and 1.5" guiding looks like - and it is quite surprising.  Something else to worry about, but at least I understand it a bit now.

 

 

Edited by don4l
  • Like 4

Share this post


Link to post
Share on other sites
10 minutes ago, don4l said:

It's been a brilliant few nights!

Getting such a load of data seems to take some of the pressure off and allows a bit of experimentation.

I've just used a feature in CCDCiel for the first time, and it has worked brilliantly.  After doing the meridian flip I loaded up the last sub and told it to move the mount to the centre of the image.  It platesolved, then slewed, and platesolved again.  After a minute or two it told me that it was 0.47 arcminutes away from target. 

I like this feature a lot!

Touch wood, I seem to have got the autoguiding working properly again, although I have no idea what was causing the problems.  I have learned what the difference is between 0.7" and 1.5" guiding looks like - and it is quite surprising.  Something else to worry about, but at least I understand it a bit now.

 

 

Its magic when you learn how to do that! Makes things so much easier.

  • Like 1

Share this post


Link to post
Share on other sites

I often hear about refocusing due to temperature changes throughout the night, but have never done this myself... I'm a bit puzzled as to how I would as well... at the start of the session I use a bahitnov mask and focus on a bright star, but if I'm then imaging a target with no bright stars in the fov how can I refocus ?

Edited by smr

Share this post


Link to post
Share on other sites

I'm very much in positive territory tonight. CO forecast was for a couple of reasonable hours in the evening and then clouding over. But so far it hasn't. There was a lot of fine wispy cloud early on, but now it is clear and crisp. CO still says it is cloudy, so I guess I am lucky!

Not expecting much I have been doing some testing and working with NINA for the first time. Seems to be working well. Slewed , platesolved, centred, autofocused, meridian flipped and recentred. All in all very impressive.

I will keep going until cloud or sleep overwhelms me.

  • Like 2

Share this post


Link to post
Share on other sites
Quote

there is a pretty decent MW overhead

What's that?  

  • Haha 3

Share this post


Link to post
Share on other sites
Quote

if I'm then imaging a target with no bright stars in the fov how can I refocus ?

I use a Bahtinov Mask too and to be honest I check all the filters before I start, and if all are pretty much the same I just do a sequence and don't bother to re-check.  Probably why my images are rubbish.

Carole 

  • Like 2

Share this post


Link to post
Share on other sites

I can't see the Milky Way with the naked eye now - my night vision isn't what it was.

  • Sad 2

Share this post


Link to post
Share on other sites

Really do need to buy a proper astro camera. I've got a superb view of the East and South and the Orion Constellation, could keep imaging it until it dips below the horizon pretty much!

  • Like 1

Share this post


Link to post
Share on other sites
6 minutes ago, smr said:

I often hear about refocusing due to temperature changes throughout the night, but have never done this myself... I'm a bit puzzled as to how I would as well... at the start of the session I use a bahitnov mask and focus on a bright star, but if I'm then imaging a target with no bright stars in the fov how can I refocus ?

Some software will do this for you, by measuring the sizes of the stars as the focuser is moved.  Or you could slew to a nearby bright star and refocus using the mask, then slew back.  I'm not sure I'd favour that approach though.

James

  • Like 2

Share this post


Link to post
Share on other sites

I fancied a change tonight, so I walked to a local beach with a star tracker, modded EOS 600D and Samyang 14mm - and took a series of very wide field images of Orion and Canis Major. It will be interesting to see what I captured close to the southern horizon, which was over the sea. I only stayed for an hour, though, as it's a work night. I'm now home taking some dark frames.

As I was on the way to the beach, by the way, it seemed a little misty, but actually the view from the beach was very clear (and very, very dark 😀 ).

Regards, Mike.

  • Like 3

Share this post


Link to post
Share on other sites
3 minutes ago, carastro said:

Probably why my images are rubbish.

Only that they are anything but rubbish.....!!

  • Like 2
  • Haha 1

Share this post


Link to post
Share on other sites
15 minutes ago, smr said:

I often hear about refocusing due to temperature changes throughout the night, but have never done this myself... I'm a bit puzzled as to how I would as well... at the start of the session I use a bahitnov mask and focus on a bright star, but if I'm then imaging a target with no bright stars in the fov how can I refocus ?

It really depends on the scope that you are using.  I have an FSQ106 and an ed80 mounted side by side.  The ed80 hardly ever needs refocusing, but the FSQ is incredibly sensitive.

It will also be affected by the F ratio.  F3 only has about 20 microns "in focus zone", whereas F10 has an awful lot more (100u ?? there are calculators online).

My capture software analyses each image as it is downloaded and gives the average HFD.  If I see that rising then I need to refocus.  This evening I had to refocus every 10 minutes for the first hour.  That was mainly because I hadn't been able to let the scope cool down as I started straight after work.

 

Edited by don4l
  • Like 2

Share this post


Link to post
Share on other sites

OK, I've shut up the 'scope for the night as I can't hang around with workmen in tomorrow. Found out why my last couple of L subs were meh, light dew on the OG, despite running dew heaters, not quite high enough, a hairdryer moment solved that. M33 was also going into some gack over toward the west-ish, Bridport way.

MW was still quite reasonable though. Backs starting to complain so that might be another good reason to turn in.

 

RE: Focusing, the Sequence software that comes with ASA mounts stores a focus / synch star in the target file, so will slew to this, focus, then slew back again. Helps that ASA mounts have 0.02" resolution encoders on both axes. Unfortunately until I get my real autofocuser I can't take advantage of this.

  • Like 2

Share this post


Link to post
Share on other sites
Quote

if I'm then imaging a target with no bright stars in the fov how can I refocus ?

I use a Bahtinov Mask too and to be honest I check all the filters before I start, and if all are pretty much the same I just do a sequence and don't bother to re-check.  Probably why my images are rubbish.

Sorry I should have mentioned as some-one else has said above, if you have an electronic focusser and the right software it will do it automatically for you - apparently -  I've never used one.   There is also a method with some software of choosing a small star and measuring it's Full Width Half Maximum FWHM, but I have never managed to get that to work from home, I think you need steady skies.

Carole 

  • Like 2

Share this post


Link to post
Share on other sites

Now have 50 decent subs of the Heart and Soul in OIII - 2½ hours.

  • Like 2

Share this post


Link to post
Share on other sites
2 minutes ago, carastro said:

Sorry I should have mentioned as some-one else has said above, if you have an electronic focusser and the right software it will do it automatically for you - apparently -  I've never used one.   There is also a method with some software of choosing a small star and measuring it's Full Width Half Maximum FWHM, but I have never managed to get that to work from home, I think you need steady skies.

Carole 

Thanks Carole, not quite into the realms of electronic focusing etc. yet but will look into that.

Share this post


Link to post
Share on other sites

OK, that's it turning in early. Sad to be passing up a rare clear night but my back just said it's had enough.

'nitght and clear skies all.

  • Like 1

Share this post


Link to post
Share on other sites

Thanks Dave - goodnight 😀

Edited by Gina
  • Thanks 1

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.


×
×
  • Create New...

Important Information

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