This may assist you in orienting yourself first. It is a general webinar about using

Our extensive support pages can be found here;

We also have an active Discord community where you can get assistance from other iTelescope subscribers;

1. Introduction
2. Planning
3. Downloading your images

4. Processing
5. More

1. Introduction

Thank you for registering a Demo account.
Our Demo accounts allow 1.5 hours of free imaging on each of Telescopes 33 and 68 for a total of 3hours of session time.
(These sessions are offered in 3 x 30-minute lots on each telescope and they are automatically time limited. Your session will stop after 30 minutes.)

We hope that your sample Demo account will give you an impression of the overall iTelescope experience.

Telescope 33 is a 12.5" RCOS with an APOGEE Alta U16 (16803) camera and LRGB and HSO filters, located in Australia.

T68 is a RASA 11" with a ZWO 'one shot' color camera, located in Utah.

As a Demo user, you will not be able to make reservations ahead of time and are limited to 'live' imaging.

When we use the term 'live', we mean sitting at your computer (or with your phone/ tablet) at the same time as the telescopes are under a dark sky with the observatory roof open.

This can take some planning and some people will be in parts of the world where the local time may be somewhat inconvenient to initiate a session (paid subscribers can make reservations to run their observing plans at any time between 2 hours and 90 days ahead. How to make a reservation.)

If you understand how to use astronomy filters, then T33 will give you excellent deep sky images of nebulae and galaxies.
If you are new to astronomy, may we suggest that T68's 'one shot' color camera would be simpler (similar to using a standard DSLR).

You can use your Demo account credentials to log into either telescope, enter an observing plan
(How do I generate a plan in the Deep Sky menu) and then use the 'Acquire Images Now' button;

or alternatively, you can use the 'One click image' feature on either T33 or T68 to pick a target and select 'Submit'


Please check the Launchpad All Sky Cameras at SSO (T33) and UDRO (T68) to see when it is dark and the sky is clear, before trying to initiate a free session.
(our Demo accounts cannot reserve time ahead, so your sessions need to take place when it is dark and open at either SSO (Australia) or UDRO (Utah)).

Pay particular attention to the All Sky camera image, the sun angle (-13 degrees in this example) and that the telescope is available;

When either SSO or UDRO show 'Open', with a clear weather All Sky image, the sun is below approximately 16 degrees (-16 degrees), then it is dark enough to image.

Log into either telescope (T33 or T68) when they are 'open' and 'available' and it is dark and clear. You can then initiate your observing plan.

2. Planning

Some guidance on planning your sessions; is an excellent astroimaging resource.

Start on the left where you select the observatory of interest e.g. Siding Spring Observatory

Then choose what targets you are interested in e.g. 'Deep Sky'

select the time parameters you want (the default is all night, 4 hours above 30 degrees and various object types)


This results in a list of targets that can be sorted by various measures (size and magnitude are the two most useful)

In this example we'll select the third target, the Lagoon Nebula (simply click on the picture);

The graph on the right depicts the rise and set time for this target, using the local time at the observatory as a reference;

8:23pm Siding Spring Observatory time, the target will be high in the sky (almost overhead), hence around this time would be an ideal time to initiate a session.

To get an idea of what the target will look like, use the telescope simulator;
Select iTelescope and T33;

Here is a 120 second image (Bin2) taken through a Red filter of the Lagoon Nebula on T33;

We recommend, when starting out, choosing targets as high in the sky as possible. Our telescopes are in observatories, some (like SSO) have high walls to protect from wind but this also limits the visible horizon. Targets below approximately 45 degrees suffer from a high degree of 'air mass' i.e the lower the target, the more atmosphere that you have to look though.

Take particular note of the horizons for T33

T68 is mostly clear down to approximately 15 degrees all around.

It is possible to enter and save observing plans for quick use later; Create plan for later
Then when you log into the free telescopes, use the 'HOLD' button and this will give you a 5 minute widow within which you can enter your observing plan without worrying that someone else will use the telescope before you.

Then choose 'Run a Saved Plan';

and navigate to the plan that you saved previously via the drop-down menu (many plans can be saved and retrieved this way for future use).
Please note that each telescope needs its own observing plans; so you will need to enter the observing plan for each telescope (even if it appears to be exactly the same as you have used on another telescope).

Then 'Acquire Images'.
You can check the 'System Status' console log if you really want to (it just shows all the instructions that the telescope is following).

Once some images have been produced you can see a preview image by choosing 'System Status', 'Preview Last Image' and then 'Click Here ..."

Please note that the preview image is a highly compressed 8-bit jpeg that is 'auto stretched' by our software.
It may not really depict the actual quality of your 16 bit FITS data. It is mainly meant as a rough visual assessment of the data. 

3. Downloading your images

Once you've run a successful session, you can retrieve your images via the FTP server;

(You will receive an email to your iTelescope registered email account, we call this a transaction receipt. Please take some time to study this receipt. It has all the details of your session including weather information, billing details, and a log of all telescope operations.)


From the Launchpad choose 'Download my data';

Use your iTelescope credentials to log into the FTP server;

Navigate to the folder with your images;

select the check box next to the data you wish to download and select 'Download'

This may take a few minutes before you see any activity as the server is creating a zip archive for download. The download should then commence automatically. Depending on the speed of your connection and the amount of data this can take some time (generally a few minutes but possibly a few hours for really large gigabyte data sets (for those taking hundreds of images)). Follow the prompts in your browser to save the zipped archive to your local computer.

Once you have your files unzipped (we recommend the excellent and free 7-zip, (7-zip download page))
Then you will need to open your FITS files in a suitable processing program.

4. Processing your images

For T33 you need to be able to understand how to use astronomy filters (LRGB, HSO) to take astronomical images and how to combine the data from those filters to make a color image from the FITS data provided.

For T68 the images are in color but still require particular software that recognises 'FITS' files;

(Note that all the data is provided both as completely calibrated data and raw data. Please download the data that you desire. We would recommend using the calibrated data supplied by iTelescope as the simplest solution when starting out.
You may notice that there is also a 'calibration -library' in your downloads folders. All the raw calibration master files that we use to generate calibrated data is also provided for those that wish to attempt the calibrations themselves. This is an advance process and we recommend that you contact if the results of your calibrations are not as you would have expected. Also note that T68 data is provided as 'calibrated-color' (debayered) and 'calibrated' (undebayered) data; please choose whichever one suits your processing software (most likely debayered 'calibrated-color' for most applications).

iTelescope recommends Astro Pixel processor;
Astro Pixel Processor downloads page

and here is an overview of all the above in a webinar (same link as at the start of this article)

There is also a range of software that you can use;

Once you have downloaded and inspected your images, please let us know if you are not 100% satisfied (satellites interfered, moon too close, wind vibrations etc.) and we can reset your free sessions on either T33 or T68 so that you can try again.

5. More

Please ask any questions via

If your Demo experience has awakened a desire for more, please select one of our subscription plans here;

and follow the prompts to use your credit card or PayPal details
(please note that this is a recurring 28 day subscription that can be cancelled or resumed at anytime)

Many thanks for persisting with this introduction. Remote imaging has its many challenges but data from excellent telescopes under the worlds darkest skies is worth the effort.