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Equatorial Mounts For Budget Astrophotography?
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?"
They're still looking for enough users to commit to open up the beta, but Stack Exchange (the folks behind Stack Overflow, Server Fault and Super User) have a proposal up for an question & answer astronomy site:
http://area51.stackexchange.com/proposals/51/astronomy
Build it, and they will come^Hplain.
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
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.
A good motorized mount is expensive, often times exceeding the cost of the telescope. We have a few that we paid $15k for just to put $7k telescopes on.
If you're on a tight budget, but want to capture the Perseids, put a DSLR on a standard tripod. Wide shots, say 18-55mm lens, you can expose for 30 seconds or so without noticing any earth rotation in your field. Take a bunch of exposures, and use a program like the free Deep Sky Stacker to align them into a final image with total exposure time equal to all the shots combines. I haven't taken any like this for meteor showers yet, but you can get some stunning shots of the Milky Way, and some of the bigger objects in the night sky. If you use a narrower field lens, like 100mm, then you might only get 10-15sec exposures, but just take several hundred and let the stacker program turn them into awesome.
If you want a motorized mount for astroimaging you get what you pay for.. A cheap one will have poor periodic error and vibration. I got a now discontinued LXD75, but due to the cheap plastic gears it's made with, I wish now I went with a more expensive EQ6 to get more accurate guiding.
I hope you are not intending on photographing a meteor from a telescope.
The most common thing to when photographing meteor showers is to point to the pole star and set your SLR (hopefully manual, film based on a tripod with a cable for the shutter) to a B setting and take a shot for a couple of hours. This produces really nice star trails and the occasional meteor.
If you are piggybacking the camera to a telescope you should not have any issues with the motor vibration, but you will need to beware of wind.
Save up your money and buy a Meade LX200, you can now get the older models (I personally think are better) for around 2000$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.
GO BLUE!
Check this out:
http://members.cox.net/tfangrow/hissdrive.html
Otherwise, barn door mounts:
http://www.mikeoates.org/mas/projects/scotch/
http://www.astunit.com/tonkinsastro/atm/projects/scotch.htm
http://www.davetrott.com/DoubleArmBarnDoor.html
Equatorial platforms:
http://tech.groups.yahoo.com/group/eqplatforms/
Lots of other links:
http://members.ziggo.nl/jhm.vangastel/Astronomy/links.htm
A Gnu is a good mount, available on equatorial regions, and it's free!
I'm working on the mirror for a telescope now... I'm told by someone who I'm working with that, if you're at all mechanically inclined, you can start with one of the less expensive mounts and do some work to improve it.
Yeah, just what the title reads. I'm simply curious.
If you are trying to photograph deep sky objects through a mid sized telescope, I don't think you will find a mount in your budget range, unless you can get one used off of ebay or some such. The tabletop equatorial mount might be appropriate if you're just doing the sky. However, for a telescope, just the motors for a good equatorial drive will set you back $100 or more....
If you are only trying to photograph planets or the moon, you won't need any tracking ability to get spectacular photographs.
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
Violence is the last refuge of the incompetent. Polar Scope Align for iOS
Point to the pole star?
I'm in the southern hemisphere, you insensitive clod!
In that budget range, just buy a used commercial drive base from a broken small equatorial telescope like a Meade ETX-70 or ETX-90 that are typically sold in Wal-Mart at Chirstmas time. It is common to find them on ebay cheap with broken optical components. Another option is an old B&L 4000, the optics on most of these were junk, but they had a decent AC powered drive base, and since everyone knows the optics were junk, just ask google, they tend to sell cheap ($100 or so) on ebay.
Ike
I've been thinking about this for a while as I have built myself an 8" scope from the ground up, including the mount. And it all works well, except that it doesn't track. And everytime I look for a clock drive to put on there I end up only seeing options somewhere between $300-$30k. All I need is a big worm gear setup and a slow enough constant speed motor, but it seems gears are a lot more expensive than I think they should be. The weight of my scope is about 13lbs, with counterweights as it is now, closer to 15lbs... anyone know of an astrophotographic worthy clock drive and where to get it? I wouldn't mind spending $200-$300 if I knew it was going to work flawlessly, but it seems all the low end prices are flimsy replacment mounts, and all the clock drives sold separately are expensive professional grade setups.
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 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 and it required a complete tear down, polishing, and rebuild before it was even capable of astrophotography...and that's at $600!!
http://hardware.slashdot.org/story/10/07/31/2040226/Microsoft-Tech-Can-Deblur-Images-Automatically
Well, you'd better grab a shovel and start digging then...
To shoot a meteor shower, you need nothing more than a tripod, a camera with a ~50mm lens, warm clothes and patience.
You don't want to take real long exposures to get meteors, too long and light pollution/sky glow will likely mess up your pictures.
Just point near the radiant (I try for framing a nice constellation nearby), and using a cable release take 20-30 second exposures while watching the area of sky that the camera sees. Most exposures obviously won't have meteors, but when you do catch one, take note of which exposure for later when you delete the (many) exposures that didn't have a meteor. When you do capture a meteor, start a new exposure because keeping the shutter open longer won't likely gain you anything.
If you're looking at doing further astrophotography beyond a meteor shower, then you will need some form of tracking. Making a barn-door tracker can be a cheap option to get started (YMMV, depending on how good you are at making stuff and your level of patience!).
As with the rest of astronomy, you can start out spending a bunch of money on stuff you don't really need or use, so it's always good to start cheap and see if you are really into it. If your interest holds, you will find a way to buy up.
A house divided against itself cannot stand.
I see a $250 motorized equatorial mount on craigslist (sf bayarea) for $100.
Religion is poison to rationality, and we lose sight of that at our own peril. -- Lurker2288
He would point to the south pole star, you insensitive clod!
(if he can see it!) :-)
John Kramer
God may be my co-pilot, but the devil is my backseat driver.
You can always try the Capella plans from the link below. I built it and it works fairly well. I find the friction required to get a proper static/stable lock on anything insufficient. Could be my implementation of the plans. I'm modifying the concept to use a couple of worm gears to stabilize everything. I've purchased some worm gears for garage door openers with 0.5" shafts. They are sturdy enough to keep a lock on an object. Probably not accurate enough to track an object over an extended period of time but, this is just for fun right?
have a look see: http://solar.physics.montana.edu/larson/Capella/index.html
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)
... or did the title of this article help you win at "Buzzword Bingo"? Probably just me :)
Cheap mounts are mostly OK with vibration as long as you let it settle for a minute and don't have any wind (that's the killer). Otherwise they're OK for short shots (a couple of minutes). You are more likely to have a misalignment or having periodic errors on the gears. They won't matter for wide and short shots. You can still do reasonably good quality pictures within those scenarios.
If you are using an SLR, invest on an IR remote and before you start shooting use a dark cardboard to block the light, not touching the scope hit the remote, wait for the vibrations to die down and then remove the carboard, then when you want to stop, hold the cardboard in front of the scope, hit the IR remote button again.
A motor mount is very nice but don't use your lack of one to not take photos of the perseids.
The best photos will be done with fairly wide-angle lenses and exposures of minutes and while some of the star field motion will be noticeable it will not be objectionable. The perseids will be bright streaks obviously different than the tiny little arcs executed by the stars.
Now, if you want to make dark-sky photos of small faint objects, with truly long exposures and much narrower fields of view, a motor mount is indeed a necessity. But not for the perseids.
Tim.
a used vixen Super Polaris with motors and controller was $550 for me. astromart.com was the source, and it was local so I saved on shipping.
If you're using a Canon cam, check out the Canon Hack Development Kit
http://chdk.wikia.com/
There are a couple of user scripts geared towards capturing things like meteor showers and lightning strikes, as well a lot of other useful tweaks. Opens up a lot of interesting features, like raw mode on low-end models.
Because with this budget, a good equatorial mount with motors (like an EQ6) is really out of your budget.
You can try to find a EQ3-2 with RA motor, used, this is a good "small" mount.
"Science will win because it works." - Stephen Hawking
Amazon - has one - http://www.amazon.com/Orion-Min-EQ-Tabletop-Equatorial-Mount/dp/B0000XMX8O - from Orion for $59.99 (plus $15 shipping - $15? WTF?)
The motors and controller bump the price up to $132 (plus some extortionate shipping charge) - maybe not still within your budget?
BTW, $350 **IS** a midpriced mount. Astronomy gear is grossly overpriced, IMO.
I have a motorized equatorial mount that is of very hefty precision design. You would have to pick it up from Santa Fe NM, but its perfect for astrophotography. -Simon.
At first I took this to be asking 'What are the best mountain ranges on the equator for astronomical observation?'
Arguably a more interesting question.
When we photograph meteors for genuine data collection, we don't use a mount at all. We set up a ring of cameras with each covering several degrees of sky, and let them all take five or ten minute exposures. It's your best hope of catching a bright one and several faint ones. If you're using a decently short lens (50mm, 35mm), (a) you'll catch more meteors and (b) the star trails are less notable, or you won't care about them.
Remember, with meteors being an atmospheric phenomenon, you'll catch more closer to the horizon than looking up. (You're looking through more air.)
And it makes no difference if you're looking toward or away from the radiant for meteor count.
...on the horses to mount an entire telescope on them! Its bad enough the sharks have head lasers, but to break the back of a poor horse just so you can find the Big Dipper is just plain vicious Who are you, Michael Vick?
I know people who've had great success with the AstroTrac TT320X-AG mount. I've always wanted to try one myself, but at US$550.00 I think it's about three times the price it should be:
http://www.astrotrac.com/Default.aspx?p=tt320x-ag
Easy enough.... anything from clock mechanism to electronic mechanism.
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Voting up, Voting down - If I really gave a fuck about your approval or not, I'd come and ask you.