Looking to do star time lapse with DSLR only...which mount?

[phantasms]

Hi,

I'm trying to do a project for my astronomy class.  Part of what I'm going to need for this project is the ability to do time-lapse star photography.  I've included a link below so you can see exactly what type I'm talking about.  I'm going to use my Canon 5D mkiii for this.  I have a pretty good idea of the camera settings however I'm not sure of the best mount to get.  Frankly I think the footage not accounting for field rotation looks best so I can just go with an alt-az.  I was considering something like this : http://www.telescope.com/Mounts-Tripods/Altazimuth-Mounts-Tripods/Orion-StarBlast-AutoTracker-Altazimuth-Mount/pc/-1/c/2/sc/35/p/102781.uts

I know the cheaper mounts aren't good for real deal space stuff with a telescope but for a DSLR and maybe 40 second or so exposure time I was thinking this may cut it.

what I'm looking to achieve:

http://youtu.be/dcYpYSGKY2k?t=16m14s

I'd appreciate any thoughts, insights, experience that anyone might have on the subject.

Thank you very much!

Best,

Gene

[jambouk]

I think any motorised alt-az mount will do the trick as long as you've got it reasonably well aligned so the centre of the frame stays in the centre; make sure also you can supply it with a continuous source of power throughout the night.

Make sure also you've got some dew control measures for the camera lens.

Good luck.

James

[phantasms]

Thank you!

I think any motorised alt-az mount will do the trick as long as you've got it reasonably well aligned so the centre of the frame stays in the centre; make sure also you can supply it with a continuous source of power throughout the night.

Make sure also you've got some dew control measures for the camera lens.

Good luck.

James

Thank you!  Do you have any knowledge with dew control measures?

Best,

Gene

[jambouk]

If doing an hour or so, heated hand pads will help; just open the packet, shake and wake them up, then put an elastic band around them and the lens and hey presto!

If you are doing longer exposures, i use a dedicated dew band designed for small telescopes or finder scopes or eye pieces, and plug it into my dew controller. People make their own dew controllers (i'm led to believe this is easy); people even make their own dew bands.

A guide i put together about star trails may help you, but it sounds like you are a bit more advanced than this:

http://www.eastmidlandsstargazers.org.uk/topic/6922-star-trail-guide/?fromsearch=1

Jd

[ronin]

Wouldn't you just put the camera on a fixed tripod and take images at whatever intervals then stitch them together?

Cannot see why you would want a driven mount at all.

If the mount tracked the sky then the sky stays still and it is the ground that you would see move in the timelapse, which I guess is not what is wanted.

[jambouk]

Ronin, check out the video which is linked in the original post (from about 16:45 oneards); the desired effect is to have both the sky rotating, and the camera appearing to move with respect to the foreground too.

Jd

[TractionMan]

It looks like a motorized camera slider has been used and not "just" an altaz mount. 

[bogdog]

something like this should give the results you want

http://www.telescopehouse.com/acatalog/Orion-Mini-EQ---Drive-Megadeal.html

[Astrosurf]

I'd love to have a go too! This looks helpful:

http://www.jamesvernacotola.com/Resources/How-To-Photograph-Star-Trails/12233655_V7cX4D

Alexxx

[phantasms]

Wouldn't you just put the camera on a fixed tripod and take images at whatever intervals then stitch them together?

Cannot see why you would want a driven mount at all.

If the mount tracked the sky then the sky stays still and it is the ground that you would see move in the timelapse, which I guess is not what is wanted.

Also I'm looking to get exposures of around 40 seconds.  Usually anything past 30 you start getting trails unless the whole setup is moving somewhat in line with the stars.

Best,

Gene

[phantasms]

If doing an hour or so, heated hand pads will help; just open the packet, shake and wake them up, then put an elastic band around them and the lens and hey presto!

If you are doing longer exposures, i use a dedicated dew band designed for small telescopes or finder scopes or eye pieces, and plug it into my dew controller. People make their own dew controllers (i'm led to believe this is easy); people even make their own dew bands.

A guide i put together about star trails may help you, but it sounds like you are a bit more advanced than this:

http://www.eastmidlandsstargazers.org.uk/topic/6922-star-trail-guide/?fromsearch=1

Jd

Perfect.  Thank you!  I certainly don't want to lose a night to dew.

It looks like a motorized camera slider has been used and not "just" an altaz mount. 

What would be the difference?

something like this should give the results you want

http://www.telescopehouse.com/acatalog/Orion-Mini-EQ---Drive-Megadeal.html

Great.  I'll check that one out too.

I'd love to have a go too! This looks helpful:

http://www.jamesvernacotola.com/Resources/How-To-Photograph-Star-Trails/12233655_V7cX4D

Alexxx

Awesome.  Just wait till you guys see what I use as the foreground.

Best,

Gene

[frugal]

Also I'm looking to get exposures of around 40 seconds.  Usually anything past 30 you start getting trails unless the whole setup is moving somewhat in line with the stars.

Best,

Gene

True, but if you are going to downscale the images from the full camera resolution to HD (1920x1080), then you will shorten the trails by a factor of  about 4 as well. Plus if the video is showing the stars moving through the sky, you might actually want a bit of trailing to provide a small amount of motion blur, otherwise you can get a stop-motion effect rather than a smooth look to your final footage.

[TractionMan]

What would be the difference?

Best,

Gene

A camera slider is a small sled on a rail, like a smaller version av a camera dolly. Very popular with DSLR videography and time lapse photography. There are commercial motorized options such as: http://www.digislider.co.uk/  but they tend to be quite expensive. However, I've seen a few DIY jobs on the web while looking into this myself.

[RobertC]

There is a few people who i follow on facebook who do a lot of this stuff. https://www.facebook.com/Seantos?fref=ts Sean Parker does some really amazing work ! I highly recommend you take a look for a few mins.

[phantasms]

True, but if you are going to downscale the images from the full camera resolution to HD (1920x1080), then you will shorten the trails by a factor of  about 4 as well. Plus if the video is showing the stars moving through the sky, you might actually want a bit of trailing to provide a small amount of motion blur, otherwise you can get a stop-motion effect rather than a smooth look to your final footage.

A camera slider is a small sled on a rail, like a smaller version av a camera dolly. Very popular with DSLR videography and time lapse photography. There are commercial motorized options such as: http://www.digislider.co.uk/  but they tend to be quite expensive. However, I've seen a few DIY jobs on the web while looking into this myself.

There is a few people who i follow on facebook who do a lot of this stuff. https://www.facebook.com/Seantos?fref=ts Sean Parker does some really amazing work ! I highly recommend you take a look for a few mins.

All good stuff guys.  Thank you!  

I'm very excited about this project.  And this part is the easy part! lol

Best,

Gene

[TractionMan]

Good luck with your project. Looking forward to see the result.