Transcript

INSTRUCTOR:

OK. So here I am logged into telescope.org, ready to retrieve some of my variable star images for using the aperture photometry. And the first thing I'm going to do is to go to the Your Requests page. And here I've got a list of all the images that I've requested, the various objects. I've got some requests for EA2 and EA1. Those images haven't been taken yet, so they've just been listed as waiting.

But further down, I've got some images of variable star EA3 from our list. Those are shown as complete, so those are ready for me to go ahead and collect. I've got a number of these because I've been bracketing my exposures. I'm going to go ahead and choose this one. Click on that, it'll take me to the view page. There's not an awful lot to see at the moment, but I'm going to fix that up in a moment.

First of all, I'm going to go to the Data tab, just to confirm that this is the image I wanted. So I can check on this tab, I can check the exposure. 30 seconds. That's right. That's one of my bracketed exposures. And the green filter. So that is indeed the image that I wanted.

And so I can then go across to the Edit tab. And this time my image is loading here, and the software is going to adjust the contrast and the brightness so that we can see what's going on. I've got a nice image here, with plenty of stars in the field of view. And I can even go ahead and adjust the contrast a little bit more to darken the background, make it very easy to see what's going on.

Now, I'm fairly confident in this image that this star here, close to the centre, is the variable star that I'm interested in. If I've entered my coordinates correctly and the telescope has gone to those coordinates, the target star should be at or very close to the centre of the frame, the centre of the field of view. And I can even zoom in a little bit using the zoom slider. I'm fairly confident this is the star that I'm interested in, but of course, we're going to use the Finder charts later on to absolutely confirm that that's the correct star.

For now, I'm going to go ahead and save my image. And when I do that, I'll be saving it in the FITS astronomical data format, which is a sort of raw data format. So it will save. It won't save any of the changes that we've made to brightness and contrast. It'll just save the raw data.

So to do that, I'll go ahead to the Save icon on the floppy disc. And this time I'm selecting FITS. Save file. And I've already got a location set up where I want to save all my coast images. So I'll just go ahead and save the image in there. And that's my image saved, ready for the next step, which will be the aperture photometry itself.