Imaging Planets Using Webcams

saturn_may8_2016_logitech4000-2
Saturn captured through eyepiece projection method with a 4-in f/9 refractor and a web camera

Images of planets may be captured with a web camera and a telescope using prime focus method and eyepiece projection method.

The prime focus method involves replacing the web camera’s lens with the lens (or mirror) of a telescope.

The eyepiece projection method involves projecting an image onto the web camera’s sensor with the help of an eyepiece.

Image Processing

Record 2-3 minute videos of the planet and then use a software to extract still image frames from the video. Look for the best-looking image (sharp, clear, with lots of details) and then use a software to look for other images that are similar in quality. These frames will be registered (compared and aligned automatically) and then stacked (combined) to form one single image using a software such as IRIS (Windows) or SIRIL (Linux).

Jupiter captured through eyepiece projection method with a 4-in f/9 refractor and a web camera

Related link: Dash Camera as Planetary Camera

Night Sky in Focus
Astronomy and Amateur Radio
© Anthony Urbano (Manila, Philippines)

39 thoughts on “Imaging Planets Using Webcams

  1. Kuya Eteny, paano kapag puro still images lang ang meron lang ako? Okay pa rin bang gamitin ang Registax? I have about 7 images of the Milky Way galaxy pero iba-iba ang anggulo. Thanks and will appreciate your reply for this. :)

    • There is an option to process still images (jpeg, etc.) instead of video, but for best results, images must be identical in all aspects. Good luck!

  2. Hey, i’ve build a telescope using 20cm mirror on the bottom. and im using a webcam with its lens removed and without any of the adapter looking straight through a 45 degree slanted mirror down to the 20cm one with 600mm long, what i the magnifier of the image that webcam see? since there’s no lens on it anymore

  3. HI, I have a logitec 4000 which I want to use for astroguiding and/or as a camera. However most of the adapters are for the SPC900NC. Do you know if the adaptors are interchangeable i.e. compatible screw threads?

    • Hi Andy, I am not sure if they do have exactly the same screw threads/specs, but in my case I am using simply the same adapter for both of my SPC900NC and Logitech 4000 web cameras. My best guess is that those commercially-available adapters for SPC900NC should also work for the Logitech 4000. Just be extra careful in screwing in the adapter. Clear skies!

      • Many thanks, that’s good enough for me to give it a try and order one.
        Clear skies to you too!

  4. Hi Eteny,

    I have tried using the Prime Focus method but the images I get are huge. One thing I tried with a different webcam was to keep the lens on it and keep the lens on the telescope also. I was able to see what I would see, but I don’t see this method used by anyone. Why would this not be favored by anyone? I tried to do the same with an HD webcam and I am having a very hard time lining it up just right with lenses and all in place. Any tips? Thx – Sergio

    • Hi Sergio,

      The method you are describing is called afocal imaging, wherein you use webcam with its lens, mounted on a telescope with an eyepiece. In any type of imaging, we try to minimize the number of optical elements between the object (e.g., the planet) and the camera’s sensor, since using more optical elements means more imperfections *may* be introduced in the final image. The simpler the setup is, the better. If you look at the afocal method, you’ll see that there are a lot of optical elements used which could introduce all sorts of problems related to the clarity of the image, which makes it less desirable. And even if you have superb optics, because of so many optical elements, less light will reach the sensor.

      To minimize imperfections, other imaging techniques/methods may be employed. Just remember that as much as possible, you want to get larger ‘zoomed in’ images to allow you to get more details, regardless of the method used (of course within the practical limits of the steadiness of the atmosphere and the specs of your equipment). There are pros and cons, and you will have to try out each one and decide which ones will work best for you.

      • Eteny,

        Thank you very much for taking the time to reply to me. What you say makes sense. I will experiment some more. With prime focus the image seems too big and blurred, it seems that my short 600mm refractor’s focal length is a problem. I tried Eyepiece projection and I can’t seem to focus the image, do I need more length beyond the focuser? In other words I probably need to put the webcam (with no lens) several inches away from the end of the eyepiece, correct?

        Thx, Sergio

      • In eyepiece projection, what I usually do is to center and focus the target first by looking directly through the eyepiece. Once centered and focused, I then mount the web camera (with its lens removed) immediately on top of the eyepiece. A fuzzy object then shows up in my monitor. Sharp focus is achieved by simply adjusting the focuser. Note however that sometimes focus travel is not enough (tube too short), thus, you’ll need to use a tube extender (I use Barlows with the ‘lens’ removed). I recommend doing a trial imaging session with the moon first before attempting to image a planet. Good luck!

  5. Do you have a link to where I can buy a eyepiece projection adapter – preferably on amazon uk. Ice seen lots of dslr projectors so afraid of buying the wrong one.

    You’re using a refactor in the pictures above?

    • Hi Sean,
      Send me the link to the items you are planning to purchase and I’ll help you identify (based on the item description/specs) if it is compatible or not. Good luck!

      • Those are definitely the type of adapter you are looking for! Remember that what they are selling are simply the eyepiece projection adapter. You still need to purchase a webcam to telescope adapter (for use with webcams) or a T-ring plus T-adapter setup, if to be used with a DSLR. Good luck!

    • just got my new skywatcher 6 inches diameter great for moon and planets and more starting photos soon as the weather clears out with my digital rebel xti 450d

      • For the last two months here in South Ontario at night cloudy all night, did not get any clear sky at all. Hoping it will be in August if not only September and October should be good for watching at night. No luck for me so far.

      • hi I just bought a luminous 2 x.5 two inches barlow and one eyepiece Antares w70 series two inches 31mm with my skywatcher 150-750 black diamond which is very good to look, did I make a good choice need some advice

  6. Don’t you need some kind of T-ring to webcam adapter for eyepiece projection? I have a standard 1.25″ camera adapter that holds eyepieces and has a T thread on the other end. With an eyepiece inserted there is no room to mount a webcam…

    • Hi Chumley, an ‘eyepiece projection adapter‘ solves that problem. It allows an eyepiece to connect to a focuser while and at the same time, allows a webcam to be attached to the eyepiece. Note that it also allows you to change the distance (separation) between the eyepiece and the web camera, which is very important in adjusting the size of the projected image. A larger distance or separation will yield a larger image.

  7. hi Eteny what do you suggest using two inches barlow luminos 2x.5 with two inches eyepieces Antares 31mm is that a good choice to upgrade eyepiece and barlow for a skywatcher 150/750 6 inches diameter thanks for and answer

    • Hi rheal,

      I have not used that particular Barlow, thus, I am unable to provide a concrete feedback. In any case, I do find a Barlow lens useful as it allows you to “zoom in” on planets every once in a while. For more info on Barlows, click here. Good luck!

      • tonight will be my first reel night cause have clear sky for tree day since june I will injoy it

  8. Hi.
    How can i use a moon filter in conjunction with the philips webcam?
    I am using a Williams 2″ diagonal + 1.25″ adapter.

  9. This is a great article! I have been interested in webcam astrophotography for some time but most articles I read assume you have a refractor. I built an 8″ f7 a couple years ago and have been dying to see what kind of planetary shots I can get. I tried a couple webcams but it never really produced anything but frustration and disappointment. But now I’m thinking I had the lack of adjustment for the sensor distance. I’m going to vet back into this as soon as it starts to warm up. I did read somewhere to test the rig in the daytime, targeting a distant object to make sure webcam is aligned with eyepieces too.

  10. I have a telescope like 150×700 star-tracker and have webcam. I try to attached a webcam along with the remove lance of the webcam with a adapter. I also attached cellphone along with OTG cabal and have a app also. Every thing are done but I can view any image on the display of my cellphone. Let me tell how I do the same? Hope your reply.

  11. Hello,
    I have been using afocal method with a cell phone camera in place of the webcam using a clamp. The resolution is 1080p with 30fps. Would I see improvement if I used a cheap webcam instead (for planets)?
    Thank you

    • The improvement will be astronomical, because with a webcam (with the lens removed), the optical train (prime focus) will be far better as there will be no low quality lenses in between the objective (main mirror or lens) and the imaging sensor.

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