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.

sgl_imaging_challenge_celestial_motion.thumb.jpg.a9e9349c45f96ed7928eb32f1baf76ed.jpg

Gib007

My tutorial for installing, setting up and using AstroTortilla

Recommended Posts

Cheers for that Louise

Looks like is misread the tutorial...I thought you put in 20% of your minimum FOV, not take 20% off and use 80%.

Will adjust my setup accordingly and see what difference that makes to it

Share this post


Link to post
Share on other sites

Cheers for that Louise

Looks like is misread the tutorial...I thought you put in 20% of your minimum FOV, not take 20% off and use 80%.

Will adjust my setup accordingly and see what difference that makes to it

Hi

TBH I'm not convinced by the need to base which index files you need on +/- 20% - surely the exact value would do? However, I just copied from the light vortex guide! But it won't do any harm.  Having extra index files won't cause a major problem but might increase the time it takes to solve. Think of them like a database containing superfluous records that you will never need or use.  As I mentioned previously, you'll be able to monitor which particular index files are being used for your scope/camera combo. It takes a number of different solves to deduce this but once you are confident you know which ones you don't use, you can move the unused ones to a different folder. Once optimised you should be able to solve an image in something like 4-20 secs :) Once you've solved a particular image you can re-slew, solve again, and your target will be centred :) You can also solve previously saved images which can be useful.

Louise

Share this post


Link to post
Share on other sites

Cheers for that Louise

Looks like is misread the tutorial...I thought you put in 20% of your minimum FOV, not take 20% off and use 80%.

Will adjust my setup accordingly and see what difference that makes to it

Hmm. I thought the Light Vortex tutorial states that you should take 20% of the smallest FOV. I quote:

For example, let us say that I only have the Borg 77EDII telescope and QSI 660i CCD camera. We calculated the field of view to be 1.95 degrees x 1.56 degrees for this setup. We therefore take our widest field of view here to be 1.95 degrees and the narrowest to be 1.56 degrees. 20% of the narrowest is then 0.312 degrees (or 18.72 arcminutes, multiplying by 60) and we have our numbers for selecting appropriate astrometric index files.

So, shelster1973, I think your original calculate is correct.

Regards

John

Share this post


Link to post
Share on other sites

Strange....just put other numbers in and AT resolved fine. Am currently imaging Orion Neb. Will switch over to Bode at 2000 as Orion goes out of site by then.

Sent from my SM-N910F using Tapatalk

Share this post


Link to post
Share on other sites

Hmm. I thought the Light Vortex tutorial states that you should take 20% of the smallest FOV. I quote:

For example, let us say that I only have the Borg 77EDII telescope and QSI 660i CCD camera. We calculated the field of view to be 1.95 degrees x 1.56 degrees for this setup. We therefore take our widest field of view here to be 1.95 degrees and the narrowest to be 1.56 degrees. 20% of the narrowest is then 0.312 degrees (or 18.72 arcminutes, multiplying by 60) and we have our numbers for selecting appropriate astrometric index files.

So, shelster1973, I think your original calculate is correct.

Regards

John

Hi

It does actually say that. You can download the smaller indexes if you like and see which ones AT actually use to solve :)

You can download them all if you really want!

Louise

Share this post


Link to post
Share on other sites

Hi

It does actually say that. You can download the smaller indexes if you like and see which ones AT actually use to solve :)

You can download them all if you really want!

Louise

Just for the fun of it, I downloaded them all for my local Astrometry.net install for SGPro. 32GB I think! Most of them are redundant. To speed up platesolving I only use a small subset (as reported by the ANSVR log file).

Regards

John

Share this post


Link to post
Share on other sites

Isnt it typical...I finally get things working and then the clouds roll in.  Only managed to get 13 x 180s images of Orion Neb this evening.

Noticed a few issues but was aware of them before.  My collimation was off as had rotated the primary in its cell earlier today so as to line up the hotspot bits with the primary adjustment knobs (as shown in the Catseye video).  Had a case of CBA when it came to collimating tonight as my laser colli was upstairs and I was outside.......poor sho I know.  Also focus id slightly off too.  Biggest mistake was not having enough charge in my camera battery.  Had it set for shorter esposures so as to compensate for blown out core, but it died.  Still, was a good chance to get out and grab some images again.

Anyway, here is link to JPG of one frame, unstacked

get.jpg

Share this post


Link to post
Share on other sites

Do not set -H and -L values without setting the -u  value.  Personally, I always use "-u app", as that is what the solver reports back.

-L / --scale-low <scale>: lower bound of image scale estimate  -H / --scale-high <scale>: upper bound of image scale estimate-u / --scale-units <units>: in what units are the lower and upper bounds?     choices:  "degwidth", "degw", "dw"   : width of the image, in degrees (default)               "arcminwidth", "amw", "aw" : width of the image, in arcminutes               "arcsecperpix", "app": arcseconds per pixel               "focalmm": 35-mm (width-based) equivalent focal length

Share this post


Link to post
Share on other sites

Ooh, just recently had an issure with AT - I've tried using 2x2 binning and it really didn't work - so I went back to 1x1 binning and it found me again. What a drag sometimes...

Share this post


Link to post
Share on other sites

I have been successfully using AT for some time now with my set up - Explore Scientific 102mm, Canon 650D DSLR, Cartes Du Ciel and APT.   After the solve AT always re centred the target image in my field of view.

However, the last few attempts to plate solve ( with sync scope and re slew to target ) AT solves the image in 90 or so seconds but does not then re centre the target.  I have not changed any settings within AT.   Why won't AT re centre the image after solving?

Share this post


Link to post
Share on other sites

Hi

I've noticed that happens sometimes too. I suspect that if it's already spot-on it may not then re-slew - maybe a bug, I'm not sure.

Louise

Share this post


Link to post
Share on other sites

Strange one as I have not changed the settings or anything.  Thanks Louise, I need to have a play again and see what happens. :laugh:

Share this post


Link to post
Share on other sites

Yeah it is a bit odd. I've thought about posting a problem report on their forum but it's not a big deal really. Maybe there's a new release on the horizon - that would be good!

Louise

Share this post


Link to post
Share on other sites

Hoping someone can help me with this!

Trying to get AT working on my imaging netbook but get the following log errors (it doesn't even start looking through indices).

Thing is, I have it working and solving on another PC, installed it in exactly the same way, etc. so I'm stumped.

I've re-installed twice with no change.

2015-02-24 17:09:37,453 - astrotortilla - INFO - Connecting to camera...
2015-02-24 17:09:37,467 - astrotortilla - INFO - Exposing: 5.00 seconds
2015-02-24 17:09:41,289 - astrotortilla - INFO - Reading image from camera
2015-02-24 17:09:41,305 - astrotortilla - INFO - Solving...
2015-02-24 17:09:46,407 - astrotortilla - INFO - Reading input file 1 of 1: "/cygdrive/c/Users/Astro/Desktop/IMG_7518.JPG"...

2015-02-24 17:09:47,404 - astrotortilla - INFO - /usr/bin/env: python: No such file or directory

2015-02-24 17:09:48,122 - astrotortilla - INFO -  ioutils.c:602:run_command_get_outputs Command not found: /usr/lib/astrometry/bin/image2pnm.py --sanitized-fits-outfile /tmp/tmp.sanitized.hK2iX8 --fix-sdss --infile /cygdrive/c/Users/Astro/Desktop/IMG_7518.JPG --uncompressed-outfile /tmp/tmp.uncompressed.GUrqaO --outfile /tmp/tmp.ppm.XPL5xl --ppm

2015-02-24 17:09:48,138 - astrotortilla - INFO - augment-xylist.c:585:backtick Failed to run command: /usr/lib/astrometry/bin/image2pnm.py --sanitized-fits-outfile /tmp/tmp.sanitized.hK2iX8 --fix-sdss --infile /cygdrive/c/Users/Astro/Desktop/IMG_7518.JPG --uncompressed-outfile /tmp/tmp.uncompressed.GUrqaO --outfile /tmp/tmp.ppm.XPL5xl --ppm

2015-02-24 17:09:48,154 - astrotortilla - INFO - No solution in 6.8s

Share this post


Link to post
Share on other sites

Hmmm....after posting I checked both cygwin folders, the working one is 80mb bigger!

Copying it over now.......

Share this post


Link to post
Share on other sites

That sorted it - getting some warnings about mkpasswd and group files needing to be rebuilt (!?!) but it solves anyway - less than a minute for both files I fed it so I'm chuffed with that.

Looking out the window I might even get to try it for real tonight, SHOCK! HORROR! :grin: 

Edited by Brent

Share this post


Link to post
Share on other sites

From the error it looked like Python was not installed on the failing installation.

Share this post


Link to post
Share on other sites

From the error it looked like Python was not installed on the failing installation.

Yes, I suspect you're correct. I should have realised what the problem was sooner, as the netbook never seems to download largish files without corrupting them!

Anyway, I managed to try AT outside whilst dodging clouds and it was a partial success even though I tried my best to thwart it, lol.

After polar aligning and syncing on Betelgeuse (which I realise now I didn't need to do, that's the point!), I started Stellarium and slewed to the Horsehead, took the exposure (Alnitak was in the frame now anyway), and loaded it into AT which failed to solve three times (tried various setting changes each time).

Then, on the fourth attempt at loading the image, I mis-clicked and loaded an M42 sub I'd been testing with earlier. I noticed I'd done it straight away but couldn't get at the 'Abort' button as the log window was covering it and couldn't be moved. Then, of course, AT solved it quickly and slewed, lol.

Anyway, I took the second exposure, looked at it on the LCD and didn't have a clue where it was pointing :grin:

Looking in the finder it was pointing about the same distance above Alnitak as M42 is below Alnitak so I am guessing it was in the right place considering where I'd told AT it was looking :grin:

Unfortunately, as is always the case with these things, the clouds rolled in properly and I couldn't go on and correct it.

Still, at least AT talked to the mount, I just need to get the solving down better now. I'm REALLY looking forward to being able to image the same target over multiple nights without having to spend 20 minutes trying to re-frame it first!

Edited by Brent

Share this post


Link to post
Share on other sites

The tutorial has been great for setting up Astrotortilla and a local astrometry.net server.

The only correct I would liketo make it with regard to Scale Minimum and Scale Maximum. The tutorial uses "degwidth" as the scale unit. In this case degwidth is literally the width of the image in degrees, so Scale Minimum and Scale Maximum both refer to the image width, rather than both width and height as the tutorial sets out.

As an example, on my set up the image size is 2.45x1.50 degrees, and if I use Scale Minimum as 2.4 and Scale Maximum as 2.5 it works perfectly well, and even faster than if I use Scale Minimum as 1.5

Share this post


Link to post
Share on other sites

i had a few teething problems using atsrotortilla myself for the first time the other night, firstly it wouldn`t solve, then i realised that i had loads of sync coordinates already stored in eqmod which loaded them as soon as the mount was unparked, i deleted them all from eqmod making sure that the wouldn`t apear again when restarted and tried astro tortilla again, it solved but was not quite centred on the target, i then checked my field of view and entered the exact high and low degrees field of view of my scope and camera into the tortilla settings, tried again and it solved a little better even with the exact field of view sizes, getting there but still not to my ocd standard i noticed at the bottom of the tortilla settings it was in JNow mode, i know that mt stellarium settings are J2000, so changed from JNow to J200 in tortilla and tried again and was spot on.

result.

after a couple of hours on my target, i tried a different target on the other side of the sky and for some reason tortilla wouldn`t work, turned the program off and back on again but to no avail, not sure what this problem is and haven`t had chance to try it again to see if it will work after the pc had been turned off, fingers crossed i`ll have a chance tonight but if anyone can help with the last problem i would be grateful as it looks a good bit of useful kit.

Louise,

you mentioned above the AT can plate solve from a previous image, how is this done ? would be very useful to get bang on the target night after night when doing lrgb or narrowband imaging with my rather small ccd chip.

many thanks. 

Share this post


Link to post
Share on other sites

Hi

I think I read somewhere that your scale max value should be 50% greater than your calculated fov and that the min value should be 10 or 20% of that value. You'd therefore need the index files that cover that range. Also, scale refinement set to 0.1.

Louise

Edit: I think you use the Bookmarks facility to go back to a previous solve. Also, the File Open Dialogue lets you solve a saved image.

Edited by Thalestris24

Share this post


Link to post
Share on other sites

super i`ll give that a try later finger crossed.

i did a few 10 min subs on the horse head neb the other night before i lost it over the houses so would love to add more to it if i can get the same position on it, previously i`ve tried to align the images from different nights but always end up cropping the image somewhat.

thanks for your help

Share this post


Link to post
Share on other sites

Hi

I think I read somewhere that your scale max value should be 50% greater than your calculated fov and that the min value should be 10 or 20% of that value. You'd therefore need the index files that cover that range. Also, scale refinement set to 0.1.

Interestingly I have noticed that after I solve an image, AstroTortilla changes the Max Scale to twice the width of the image in degrees and the Min Scale to half the width in degrees. So even though I tell it that the scales should be 2.5 and 2.4 respectively (my setup produces about 2.45 degrees across the frame), after solving AT updates the settings from 2.4->2.5 to 1.22 -> 4.88. So AT itself is using 50% and 200% rather than 20% and 150% as it's own documentation suggests...

Share this post


Link to post
Share on other sites

Interestingly I have noticed that after I solve an image, AstroTortilla changes the Max Scale to twice the width of the image in degrees and the Min Scale to half the width in degrees. So even though I tell it that the scales should be 2.5 and 2.4 respectively (my setup produces about 2.45 degrees across the frame), after solving AT updates the settings from 2.4->2.5 to 1.22 -> 4.88. So AT itself is using 50% and 200% rather than 20% and 150% as it's own documentation suggests...

Hmm... if your max is 2.5 how can your min be 2.4 deg? I actually put 0 in for the min and AT does update that after solving. Maybe one day I'll look through the source to try and see what it's doing.

The faq says:

"One final set of parameters that greatly affect the normal usage (i.e. the Capture and Solve -button) is the field-of-view and area restrictions. There are four settings for setting the FOV, you should set the field minimum to about half your estimated field size, maximum to twice the size, and the scale refinement to 0.1 if you don't change setups frequently. To limit the area of search (normal starry sky usage) you can reduce the search radius to 45 degrees, as this is typically the maximum sync-limit of the telescope mounts (they refuse to sync with any larger sync offsets)"

That differs from what I said before which was probably down to my rubbish memory though I'm sure I'd read it somewhere... :tongue:

Louise

Share this post


Link to post
Share on other sites

Hmm... if your max is 2.5 how can your min be 2.4 deg?

As I know that my images are exactly 2.44 degrees wide, I wanted to explicitly clamp the scale to as close to that value as I could. After all why search scales from 1.22 to 4.88 when I know that the scale will be exactly 2.44. It solves faster with 2.4 to 2.5 than with 1.22 to 4.88, but I got fed up with resetting the values.

The bottleneck on plate solving is now waiting for Backyard EOS, and converting the 22mp jpeg to a ppm and extracting the stars. So I am not too worried.

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.


  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...

Important Information

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