How to Contribute to the BAT

In order to contribute to the BAT you have to become a member by passing the bat exam. Once a member you can contribute BAT data and download BAT data by following the instructions below. I guess the biggest single thing to know is that if you run into problems you can type “@batmod” in the #batcave channel on the discord server followed by your question and one of our wonderful batmods should answer.

How to Image for the BAT

1 Point Your Telescope at a Bat Target

You’ll find co-ordinate information and reference frames on the target’s info page


2 Check the Reference frames

The reference frames are what you register your finished stack to. We anticipate our reference frame to be a bit bigger than your FOV. But don’t worry too much if it isn’t. Just make sure most of what your shooting lies within the reference frame.


Regular Imagers and Lucky Imagers have different reference frames.

Regular imager's reference frame

The reference frame for regular imagers is roughly 1.5° x  1.5° at roughly 2 arc seconds per pixel.  If your FOV is much smaller than this then you don’t need to worry too much about rotating your camera angle to match the reference frame.

Lucky Imager's reference frame

The reference frame for lucky imagers is about 0.3°x0.3° Although your rig probably has a larger field of view than this when lucky imaging it is best not to image with the full width of your sensor as capturing full size frames with an apc sized sensor slows down your frame rate and eats up 1000’s of giga bytes of storage space. We anticipate your FOV whilst lucky imaging will be smaller than 0.3°x0.3°.  Again, if your FOV is a lot smaller than 0.3° x0.3° then you don’t have to worry too much about getting your camera to the correct orientation.

3 Shoot the target

Simply shoot the target in whatever way you think is best. You can shoot with an OSC camera, an OSC camera with a light pollution filter,  a mono camera with either Red, Green Blue, Luminance, IR, Ha, Oiii, Sii or Other filters. Please don’t try lucky imaging until you have checked that your scope is sharp enough (see TEST MY SCOPE).

4 Stack your best frames

You can use whatever software you wish to stack your subs. Please don’t stack bad frames with oval shaped stars.


 If you leave the artifacts on the edge of your stack then it will degrade our final image.


If you are able to get rid of the back ground gradients from light pollution, the moon and/or imperfect flats then please do so. If you can’t you can ask someone in the bat cave for help and if you don’t get any help just upload anyway. Removing background gradients is not something lucky imagers should do as it may remove some of the signal.

5 align your stack to our reference frame

This is something that folks who don’t have Pixinsight struggle with although it is possible to do in DSS. Eventually I am hoping to have the alignment happen automatically until then if you are struggling with this stage of the process please ask another bat member to align your stack for you in the bat cave channel on my discord server.

6 Upload your aligned stack

You need to be a BAT member to upload your stacks. Simply click the link at the top of the page and follow the instructions.

How to Download and Process BAT data


  • You can download all the current data  from any particular target by clicking the download button at the top of the page. Only Bat members are able do download data. You will be able to download the target’s data directly from the BAT’s google drive.
  • You can process in whatever software you like.
  • You have permission from Big Amateur Telescope to post your process on any social media platform. Please credit Big Amateur Telescope (with a link if possible).
  • We encourage you to post your work in the #master processor’s channel onthe discord server and help us work towards producing the best possible final image.

Requirements for lucky imaging


To even begin to benefit from lucky imaging you need a scope that is sharper than the blur induced by the atmospheric wobble (which is about 3 arcseconds of blurryness), and a modern CMOS camera with a very low read noise. There is no point in trying lucky imaging with anything less as you will just end up with a very noisy shot. More info on lucky imaging theory here.

  • Scopes should be bigger than 8inches fat for a reflector and 6 inches fat for an Apo refractor(here are some scopes I recommend)
  • Scopes need to be able to shoot stars whoose blurryness (FWHM) is less than than 3 arcseconds. (you can test your scope by dropping a sub into #test-my-scope on the discord server. Please ask on the server for more details)
  • Camera need to have a very low read noise or they will struggle with noise issues. (here are some cameras I recommend)