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To the moon!

I took advantage of the fair weather and clear sky Tuesday night to make an attempt at getting some pictures of the full moon with my new Nikon D90 and Meade ETX 90 telescope. Due to the scope’s enormous focal length – 1250mm – I am able to get some very clear, detailed shots of the moon – if I can keep the camera shake under control. Unfortunately, all of these images are blurry.

I used a timer to reduce shake; however, at the time I wasn’t aware of the ability to add a delay to the mirror. The D90 does not have the option to lock the mirror up prior to exposure, and even the little movement of the mirror can cause shake on such a large lens. Turning on the delay causes the camera to wait 1 second after the mirror moves before making the exposure.

The camera does not support non-cpu lenses, so I had to experiment with exposure time. There is no auto-focus either, so I’m left using the view finder and review screen to make fine adjustments. Next time I’ll be sure to use the delay feature, as well as enlarge the image on the LCD screen to check focus. That should help me capture a clear, detailed, and focused image of the moon.

4 Comments

  1. You might try looking into an adapter that would allow you to attach your camera to the telescope. There are a variety of ways to do this. It’s your choice what to use. You can get some variation of a SteadyPix Camera Mount, which attached the camera and used to hold the camera up to the eyepiece.

    Another way is to first find a T-Ring that would fit on your camera when the lens is removed. There are a variety out there so make sure it’s one that fits the D90. The T-Ring then would allow you to attach one of the follow: prime focus adapter (which turns the telescope into your lens) or an universal adapter (can do both prime focus or eyepiece projection, where an eyepiece is put inside and the image is projected onto the sensor). A link to some of these supplies from Orion Telescopes is at the end. I personally have a T-ring and universal adapter. There are various other tools that are out there, but best to start with one of these basic methods.

    Other other thing to consider. I couldn’t tell from your post, but where you holding the camera when you took the shot? While the internal mirror might be one factor, it’s probably much less a factor than your own hands. The above methods help reduce that because it relies on the telescope to help hold the camera (though with a DSLR it couldn’t hurt to attach a tripod if possible). Might I also recommend a release timer. With this, you remove your finger from the shutter button. I’ve found that with many shots, manually pressing the button introduces an element of shaking as well. A timer release virtually eliminates this.

    One other thing I just thought of. It may not work as well with the moon due to the much shorter exposure time, but you could also do the simple trick of using a piece of black construction paper. Put it over the end of the telescope. Set the camera to take a slightly longer shot then after hitting the button, move the paper out of the way to explose. This also helps reduce the impact of the mirror moving out of the way and if you don’t have a release timer, eliminating shake from your hand as well.

    Hope that helps. E-mail me if you have questions about any of these methods.

    TripCyclone

    http://www.telescope.com/control/category/~category_id=photo_accessories/~pcategory=astro-imaging/~VIEW_INDEX=0/~VIEW_SIZE=1000000

  2. You might try looking into an adapter that would allow you to attach your camera to the telescope. There are a variety of ways to do this. It’s your choice what to use. You can get some variation of a SteadyPix Camera Mount, which attached the camera and used to hold the camera up to the eyepiece.

    Another way is to first find a T-Ring that would fit on your camera when the lens is removed. There are a variety out there so make sure it’s one that fits the D90. The T-Ring then would allow you to attach one of the follow: prime focus adapter (which turns the telescope into your lens) or an universal adapter (can do both prime focus or eyepiece projection, where an eyepiece is put inside and the image is projected onto the sensor). A link to some of these supplies from Orion Telescopes is at the end. I personally have a T-ring and universal adapter. There are various other tools that are out there, but best to start with one of these basic methods.

    Other other thing to consider. I couldn’t tell from your post, but where you holding the camera when you took the shot? While the internal mirror might be one factor, it’s probably much less a factor than your own hands. The above methods help reduce that because it relies on the telescope to help hold the camera (though with a DSLR it couldn’t hurt to attach a tripod if possible). Might I also recommend a release timer. With this, you remove your finger from the shutter button. I’ve found that with many shots, manually pressing the button introduces an element of shaking as well. A timer release virtually eliminates this.

    One other thing I just thought of. It may not work as well with the moon due to the much shorter exposure time, but you could also do the simple trick of using a piece of black construction paper. Put it over the end of the telescope. Set the camera to take a slightly longer shot then after hitting the button, move the paper out of the way to explose. This also helps reduce the impact of the mirror moving out of the way and if you don’t have a release timer, eliminating shake from your hand as well.

    Hope that helps. E-mail me if you have questions about any of these methods.

    TripCyclone

    http://www.telescope.com/control/category/~category_id=photo_accessories/~pcategory=astro-imaging/~VIEW_INDEX=0/~VIEW_SIZE=1000000

  3. Hi Trip,

    Thanks for you comments.

    I was using a T-ring and tripod for these images. The telescope is far too heavy to hold steady. I have also purchased a remote.

    I haven’t had a chance to make another attempt at taking pictures of the moon, but have used the telescope again here: http://www.jonamerica.com/photography/gallery-the-bu-bridge/

    I noticed that, if the wind was blowing, the telescope would shake. Not much I can do about that, except get a sturdier tripod.

    I like the idea of construction paper. If this were my film camera I could simply put it on bulb and wait for the exact moment. Of course, under this magnification the moon moves out of the frame after about 10 seconds.

    You have some great shots on your Flickr page. Thanks for stopping by.

  4. Hi Trip,

    Thanks for you comments.

    I was using a T-ring and tripod for these images. The telescope is far too heavy to hold steady. I have also purchased a remote.

    I haven’t had a chance to make another attempt at taking pictures of the moon, but have used the telescope again here: http://www.jonamerica.com/photography/gallery-the-bu-bridge/

    I noticed that, if the wind was blowing, the telescope would shake. Not much I can do about that, except get a sturdier tripod.

    I like the idea of construction paper. If this were my film camera I could simply put it on bulb and wait for the exact moment. Of course, under this magnification the moon moves out of the frame after about 10 seconds.

    You have some great shots on your Flickr page. Thanks for stopping by.

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