Well, I'll start off by saying I am certain I am doing it wrong! Now that I got that out of the way here is my image:

Image 1 Image 2

I have a feeling I can't see the planet because I need a filter to block out the light surrounding Jupiter, however I honestly didn't expect to have such a profound atmosphere-like disc around Jupiter.

My fiance thought it was my own eye being projected, but it was a DSLR doing the actual looking.

I am using the Celestron NexStar 127 SLT which comes stock with a 25mm and 9mm eyepiece.

Update: Okay! I focused and was able to see Jupiter, including some aspects of its atmosphere. However, I was not able to take a descent picture of it. Now I'm thinking the need for filters and proper DSLR usage methods will come into play.

Jupiter 3

  • $\begingroup$ Looks like Jupiter is blurring the image of the telescope's mirrors! :) $\endgroup$ – Mike G Apr 14 '18 at 21:18
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    $\begingroup$ The first 2 images are way out of focus. The 3rd image is still a little out of focus but is overexposed - you'll need to increase your cameras shutter speed to reduce the exposure. You don't need filters, just sort out the exposure... Video is also better for planets then you can merge the separate frames of the captured video in software like Registax to increase the detail/clarity. Good luck with your next attempt! $\endgroup$ – Mat Apr 16 '18 at 20:24
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    $\begingroup$ Here's one of Jupiter I took in 2011 with a modified webcam - imgur.com/a/LKUiE $\endgroup$ – Mat Apr 16 '18 at 20:32
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    $\begingroup$ Stop worrying about filters. That's what all beginners say, and they are almost never right. You don't need filters now. You won't need filters for a while. You may never need filters. Worry about collimation, proper focus, proper exposure, tracking, seeing, and many other things that you need to get right to obtain a good image. $\endgroup$ – Florin Andrei Apr 17 '18 at 1:54
  • $\begingroup$ Regarding the update with the over exposed Jupiter, you have to lower the exposure time. That's the first thing I would try. Have you considered getting a planetary webcam? $\endgroup$ – astromath Aug 22 '18 at 15:22

Your problem is that Jupiter is completely out of focus. You need to turn the focus knob so that the bright ring gets smaller and smaller, and then you will find that the bit in the middle is bright, and is Jupiter. Try turning the focus knob one way, and if the central dark circle gets bigger, then turn the other way, slowly.

What your pictures are showing is a magnified image of the central reflector that is located on the front corrector plate of your scope - that's the dark central circle - surrounded by the unfocussed light of Jupiter.

You could start by practising during the day, focus on distant objects (trees etc) and without the camera. Then try at night, again without a camera. Once you can use the telescope to see, try taking a photograph, again you can practise during the day. The moon might then be a good target before trying to get images of planets.

Good luck

  • $\begingroup$ I've added a paragraph recommending learning to use the telescope during the day, feel free to roll back if you disagree. $\endgroup$ – James K Apr 15 '18 at 8:11
  • $\begingroup$ JamesK. I’d been thinking about that myself. Thanks. $\endgroup$ – Dr Chuck Apr 15 '18 at 8:34

The camera's image plane was some distance away from the telescope's focal plane, so it captured a cross section of the cone of light from the telescope's mirrors. The farther from best focus, the larger and dimmer the "donut." A typical eyepiece field is located near the middle of the eyepiece barrel. The image plane of a DSLR is near the back of the camera body. When switching from an eyepiece to the camera, you probably need to adjust the telescope's focus knob considerably.

Update: Now that you found the focus, shorten the exposure or darken the ISO setting so that no pixels are fully saturated. Image manipulation software such as GIMP can brighten a slight underexposure but can't fix an overexposure. The red and blue fringes could be due to either off-axis chromatic aberration or atmospheric refraction. In either case, you can decompose and realign the (already somewhat filtered) RGB channels. Finally, unsharp masking can enhance the small-scale feature contrast.

Atmospheric turbulence degrades image sharpness to a varying degree, so take several images. A standard trick for planetary imaging these days is to record video and use software such as RegiStax to combine the best frames into a still image.

  • $\begingroup$ Do you know if that adjustment is possible on the Celestron NexStar 127 SLT? There is a focuser knob, but I'm not sure if that is what you are referring to $\endgroup$ – E.S. Apr 16 '18 at 0:18
  • $\begingroup$ @E.S. That would be the knob to use. Some Cassegrain scopes' focusers move the primary mirror instead of a drawtube, in which case you'd be moving the focused image out into the camera body. $\endgroup$ – Mike G Apr 16 '18 at 1:51

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