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Equatorial Mounts For Budget Astrophotography? 85

Posted by timothy
from the rubber-band-and-hope dept.
Timoris writes "With the Perseids approaching rapidly, I am looking for a good beginner's motorized equatorial mount for astrophotography. I have seen a few for $150 to $200, but apparently the motor vibrations make for poor photographs. Orion makes good mounts, but are out of my price range ($350) and the motor is sold separately, adding to the price half over again. Does anyone have any good experience with any low- or mid-priced mounts?"
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Equatorial Mounts For Budget Astrophotography?

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  • barn door mount (Score:5, Informative)

    by datadood (184067) on Monday August 02, 2010 @07:51AM (#33108956)

    It depends on how you are wanting to do your astrophotography. If it is a camera alone then you might consider making and/or getting a barn door mount.
    http://en.wikipedia.org/wiki/Barn_door_tracker [wikipedia.org]
    They are simple and work well.

    If you are considering astrophotography through a telescope then you'll have to have some sort of eq mount for the scope and then the prices do rise. But since you seem to be interested in photographing the Perseids then I doubt this is the case. The wide field available with just a camera would be the way to go.

  • Very tricky (Score:3, Informative)

    by riboch (1551783) on Monday August 02, 2010 @07:55AM (#33108984)

    I hope you are not intending on photographing a meteor from a telescope.

    The most common thing to when photographing meteor showers is to point to the pole star and set your SLR (hopefully manual, film based on a tripod with a cable for the shutter) to a B setting and take a shot for a couple of hours. This produces really nice star trails and the occasional meteor.

    If you are piggybacking the camera to a telescope you should not have any issues with the motor vibration, but you will need to beware of wind.

    Save up your money and buy a Meade LX200, you can now get the older models (I personally think are better) for around 2000$US, combine that with a wedge and reticle eyepiece and you are ready to go. The thing really is a light bucket and something you will be happy with, with a little training you can even work out the periodic error correction with the scope so you can do astrophotography with the camera for the eyepiece.

    If that is not satisfactory, build an adjustable wedge and buy a motor that rotates at 15 deg/hour and attach the motor to the top of the wedge with a camera on it.

  • Re:Just a DSLR (Score:3, Informative)

    by ogre7299 (229737) <jjtobin@um[ ].edu ['ich' in gap]> on Monday August 02, 2010 @08:11AM (#33109108)

    The above post is almost completely correct. However, even the cheapo equatorial drives should be ok for wide-field astrophotography with a 18-55mm lens. Their poor guiding will only start to show if you attempt to do zoomed shots on specific targets. So as long as you don't care about taking pictures through your telescope then this should be ok.

  • by Ecuador (740021) on Monday August 02, 2010 @08:12AM (#33109112) Homepage

    I mean, for a meteor shower you would need a wide field, right? Probably under 150mm? Then small tracking errors such as minor vibrations would not really show up in the photo. I remember when I was in school, I was piggybacking on my manual equatorial mount telescope and I could manage crisp photos tracking manually - I doubt the inexpensive mounts are worse.
    I am assuming you have already tried fixed-mount photographing techniques for meteors, such as star-trail exposures or shooting repeatedly at exposures just before the stars start to trail (which of course depends on your lens & what dec. you are pointing at), and are considering advancing to something else. Otherwise try that first, budget astrophotography can start VERY cheap ;)

  • Re:Just a DSLR (Score:4, Informative)

    by mcnazar (1231382) on Monday August 02, 2010 @08:20AM (#33109178)

    >like the free Deep Sky Stacker to align them into a final image with total exposure time equal to all the shots combines

    This is excellent advice on getting a much improved image quality but do note that stacking images will not give you the same results as a single image using the combined stack times.

    In other words, if each image in the stack is 20 seconds then 10 stacked images will not give you an equivalent of a 200 second exposure.

    Stacking 10 images simply improves the image quality by removing hot pixels. The result, however, is still a 20 second exposure.

    The single 200 second exposure image will contain fainter objects (and more noise) when compared to the stacked 20 second image.

  • Tripod for showers! (Score:2, Informative)

    by Caviller (1420685) on Monday August 02, 2010 @08:30AM (#33109256)
    I'm not trying to troll or be mean spirited, but take it for me, any EQ mount that is in the price range you are looking for is going to drive you absolutely bonkers...at least in the 'motorized' category. You can get close to the upper price range on a manual EQ but it would only be good enough to piggyback a camera. I have been in the hobby (astrophotography) for about 10 years now and have lived through the pain of the cheaper mounts. Unfortunally, cheap mounts are only good for one thing...making you so fed up with them that you eventually get tired of trying and give up....and keep you from actually watching the shower since you will be constantly messing with the mount.

    For what you seem to what to do from the summary above you could accomplish with the following :

    1. Stick the camera on a normal tripod and aim where the meteors are originating from with the widest angle lens you have.
    2. Take 10 sec shots after ten second shots with an ISO of at least 800, while adjusting for position every 10 or so minutes so that you keep the general area of the sky in view.
    3. The next day, use an astrophoto stacking program RegiStax [astronomie.be] to 'stitch' together your images made the previous night.

    You would be surprised how good the pictures will actually come out...and for the price of a $50 tripod.

    Now, barring that you are dead set on an EQ mount for this, I have only one piece of advice. In the land of EQ mounts, the heavier the better (less shaking, better stepping motors). And the heavier it is, the more expensive it is. There is just no getting around it. I currently have this mount [astronomics.com] and it required a complete tear down, polishing, and rebuild before it was even capable of astrophotography...and that's at $600!!
  • by BattleApple (956701) on Monday August 02, 2010 @08:42AM (#33109344)
    an equatorial mount will give you photos of meteor showers like this:
    http://www.medanku.com/wp-content/uploads/2009/08/perseid-meteor-shower.jpg [medanku.com]

    instead of this:
    http://celeb-news.net/wp-content/uploads/2009/08/meteor_shower_san_diego-8369.jpg [celeb-news.net]
  • Re:Just a DSLR (Score:5, Informative)

    by CrashandDie (1114135) on Monday August 02, 2010 @08:49AM (#33109454)

    Except that you would see the earth rotation a lot quicker than you apparently expect -- depending on where you are.

    At 50mm, depending on your earth location, you would see star trails after 8.5 seconds (equator), or 25 seconds (30 degrees from celestial pole).

    The rule of thumb is this:

    Around 30 degrees from celestial pole: 1200 / focal length = max exposure time.
    Around the equator: 400 / focal length = max exposure time.

    I use 600, because that's what I found yielded the best "rule of thumb" for me, as compared to my location.

  • Re:Just a DSLR (Score:3, Informative)

    by Kentari (1265084) on Monday August 02, 2010 @09:08AM (#33109692) Homepage

    Indeed, I agree with the parent and grand parent. For meteors you don't even need long exposure times, 30s is more than sufficient. Prepare to end up with hundreds of exposures without a meteor though... The meteors only last a fraction of a second, baring some exceptions. However, you do need the fastest lens you can get your hands on. I use my Canon 50mm f/1.4 for it, but stopped down to f/2.8 due to heavy optical aberations at any faster stop. This is just sufficient to get the brighter meteors (magnitude 1 and lower).

    If you use a cheap tracking mount or barndoor mount, you can still stack the individual images. This will give you a nice deep view of the sky (depending on the stacking process, probably without any meteors, but you can add them again).

    Personally, I avoided buying a cheap mount. I played around a bit with the mounts available at the local observatory and decided I'd rather chuck out some more money than deal with the frustration. I got myself a nice Losmandy GM-8 (nowadays around $1400 without accessories) and have enjoyed it a lot. It is still a very limited mount, only capable of handing about 10kg of equipment (scope, camera, guide scope), but very well made and easy to service and use. The results are on my website.

    Good luck with the Perseids!

  • Re:Just a DSLR (Score:2, Informative)

    by AstroMatt (1594081) on Monday August 02, 2010 @09:21AM (#33109858)
    Orion Min-Eq tabletop mount. Friend has one and loves it. $60 plus $70 for a drive if you want it. http://www.amazon.com/Orion-Min-EQ-Tabletop-Equatorial-Mount/dp/B0000XMX8O [amazon.com]
  • Here are a few tips (Score:2, Informative)

    by wirelessfreek (1326273) on Monday August 02, 2010 @09:26AM (#33109930)
    In astrophotography you will find cheap is not the way to go, you are best off buying a mount! I own a Celestron CG-5 (new version) mount which does both fine for short-focal length (50mm-to200mm) piggyback DSLR, and at prime focus with my C8-SCT. - You can shoot with out a mount, make sure you use the smallest focal-length lens you got. gives you 1-30+ seconds (depending on make, will will need to stop it down to reduce bloating of starts and abrations (Decrease F number)) - Buy a good mount. If you want it bad but dont have the money get the CG-5. - invest in a remote shooting device, your hand/ or vibrations will kill your pictures! (wireless, or build your own with a 2.5mm stereo plug and a switch) I use my computer + USB remote shooting to my camera for quick feedback of the pictures (Canon rebel XS)

If it's worth hacking on well, it's worth hacking on for money.

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