Ceci est une ancienne révision du document !
Astronomy can be a cold hobby. Sitting out in a field or garden wearing two jackets and gloves, while trying to read a sky map and trying to stop your telescope from becoming airborne can be something of a hazard. If you’re DIY-minded, you could build yourself a small observatory with a sliding roof and a warm room. Or, if you’re a sissy like me, leave your telescope out in the cold and watch things from the comfort of your own home.
L'astronomie peut être un passe-temps froid. Assis dans un champ ou un jardin portant deux gilets et des gants, tout en essayant de lire une carte du ciel et essayer d'empêcher votre télescope de s'envoler peut être quelque peu risqué. Si vous êtes bricoleur, vous pouvez construire vous-même un petit observatoire avec un toit coulissant et une pièce chaude. Ou, si vous êtes une poule mouillée comme moi, laissez votre télescope dehors dans le froid et regardez les choses dans le confort de votre propre maison.
Webcam The first thing you’ll need is a webcam. This will be your eyes, so it needs to be securely attached to your telescope or eyepiece. Some folks prefer to remove the eyepiece and put the webcam where the eyepiece should go. Some (ie: me) prefer to attach the webcam to the eyepiece to get a closer view of things. Attaching the webcam to the eyepiece is completely subjective. Some folks will buy a special attachment. Some (ie: me) will hack something up using cardboard and masking tape (don’t use gaffer’s tape, it will inevitably spoil your telescope). Whatever you do, the webcam must be stable – especially if you intend to use it for astrophotography. The webcam does not need to be big, fancy and HD. Networking I use my old laptop as my external brain. It’s linked to my desktop PC via wireless network. You could, if it came to it, use a wired network. Either way, you need to have your laptop connected to the Internet somehow. The connection we’ll make also comes in handy for wirelessly transferring any photos or videos you may take while (not quite) out in the field.
Webcam
La première chose dont vous aurez besoin est une webcam. Elle sera vos yeux, donc elle doit être solidement fixée à votre télescope ou à l'oculaire de celui-ci. Certaines personnes préfèrent retirer l'oculaire et mettre la webcam à la place de l'oculaire. Certains (comme moi) préfèrent fixer la webcam à l'oculaire pour obtenir une vue plus rapprochée des choses. La fixation de la webcam à l'oculaire est totalement de votre choix. Certaines personnes vont acheter un système particulier. Certains (comme moi) bricoler quelque chose à l'aide de carton et ruban e masquage (ne pas utiliser de ruban adhésif, il salira inévitablement votre télescope). Quoi que vous fassiez, la webcam doit être stable, surtout si vous voulez l'utiliser pour l'astrophotographie. La webcam n'a pas besoin d'être grosse, de fantaisie ni HD.
Mise en Réseau
J'utilise mon vieux portable comme un cerveau externe. Il est relié à mon PC de bureau via le réseau sans fil. Vous pouvez, si il arrive jusque là, utiliser un réseau filaire. De toute façon, vous avez besoin d'avoir votre ordinateur portable connecté à Internet de quelque manière. La connexion que nous allons faire est également très pratique pour transférer sans fil des photos ou des vidéos que vous pouvez prendre en étant (pas tout à fait) sur le terrain.
to do
Out In The Cold So, you have your webcam on your scope. Your webcam application is showing you what your webcam can see, but you’re still out in the cold. Now what? Remote Desktop First, you want to head over to: http://www.teamviewer.com, and download TeamViewer (which is free for non-commercial purposes). TeamViewer needs to be installed on both the laptop and desktop machines, and acts as both a server (transmitting) and a receiver (displaying). So, you obviously want to register with the TeamViewer website. Then, load TeamViewer on the laptop and desktop machines. First thing you want to do is go to Extras > Options, and set a password for each machine. When you first load TeamViewer, you’ll see a unique ID and password; that will change each time you load.
TIP: You should probably add TeamViewer to your list of applications that load on startup. If TeamViewer isn’t loaded you can’t connect to that machine, and there are times when you may have to send a reboot command to the machine you're logged into. Not very helpful since, if you’re at the desktop machine, you can’t see the ID of the laptop to log in with! But, help is at hand. We’ll register the machines with TeamViewer. Click the ‘Computers & Contacts’ button at the bottom right of TeamViewer, you’ll see a window pop-up. Initially, your pop-up window won’t list anything in it, but we’ll soon fix that. Click the icon second from the right, looks like a computer monitor with a ‘+’ symbol over it. This will let you register one, or more, computers with TeamViewer letting you login without having to remember a URL/IP. So, with the laptop and desktop machine registered with TeamViewer they’ll show up anytime we login to TeamViewer, and appear in the pop-up window. Simply double clicking one of the entries listed will connect to that machine.
So now (below left) I’m controlling my laptop from the comfort of my desktop. I can control it as if I was sitting in front of it. Configure settings, load/exit applications, anything. Clicking the ‘X’ in the middle left of the desktop will exit the session. You’ll also notice (in that menu that’s overlaying the laptop desktop) a ‘File Transfer’ button. This, as you can imagine, allows the transfer of files to/from the connected machines. This saves you from copying images/videos to/from USB sticks. The window that appears acts like an FTP application where you click a file(s) and click which way you’d like the file(s) to go in. So, in the image shown below, I’ve clicked a video on the laptop, and will click the blue left facing arrow (marked ‘Receive’) to transfer the file to my desktop machine. As well as having a webcam application running, you can, of course, have mount controls loaded and be controlling your mount remotely too while watching your camera. If your laptop has a webcam in it, you can point the webcam at your mount and have that on screen too!
TIP: If you leave your laptop/desktop set up, and you’re at work, you can log into any of your machines via the TeamViewer website (shown below). Although it may seem pointless to have a webcam pointing at the same patch of sky for any length of time, this setup does come in handy for astrophotography as you can leave the laptop recording video for several minutes (or hours), and keep an eye on it to make sure your camera/mount hasn’t moved or to stop/start a recording – a recording which could be put through one of the image stacking applications I mentioned last month.