goto mounts

[kingcarp]

Hi, I want to buy a mount for astrophotography, does anyone know what mount tracks the object automatically, was not sure if a goto just finds the Target, or do I need a skyscan , any help will be great, thanks

[Tinker1947]

you will need this type of mount, this is really the bottom end these take more wieght HEQ5 or NEQ6 depending on your scope ect

First Light Optics - Skywatcher EQ3 PRO Synscan GOTO

[UnderTheRain]

The mount by itself will track objects but if you want to do long exposure you will probably want to be guiding. Guiding involves a second scope and some sort of guide cam possibly connected to a laptop. You might want to get a copy of making every photon count and have a read :-)

First Light Optics - Making Every Photon Count - Steve Richards

I went down a similar train of thought but for dso's its a bit more involved. If you want to image the moon and planets you can do it with the tracking a modded webcam and some free software.

Brian

[kingcarp]

That's great, so once the program is set the gps will do the rest, thanks

[Capricorn]

That's great, so once the program is set the gps will do the rest, thanks

The GPs tells you where you are, it may tell you the time. The GPS does nothing more. It does not "do the rest".

You tell the mount additional data and you polar align the mount.

Then the mount rotates at the same rate as the earth so the object stays in the centre of view.

If you get serious use a goto as then there is the capability of using a guide scope.

[malc-c]

That's great, so once the program is set the gps will do the rest, thanks

GPS doesn't "control" the scope. It's used like any other GPS device to tell you (or the scope in that case) where on the planet it is.

There are several "levels" of astro-photography, and depending on what level you want to do, will depend on the equipment you'll need. At one end of the scale is the basic webcam which can be used with any scope from an un-driven DOB to one on an driven EQ mount.

The next stage up is typically connecting a dSLR camera body to the scope to do some long exposure images. This requires a decent mount to take the weight of the camera and scope, and something like an 150P on an EQ3 would be the minimum IMO. To get good images without field rotation an EQ mount is the preferred option. Also pulling a dSLR on an alt/az mount of the single arm type can put strain on the AZ axis.

To get decent exposures without trailing you need to have the mount driven. You can get away with a single axis drive, but a dual axis drive gives more flexible options, and is required for the next step - guiding. Guiding involves using a second scope (from a 9 x 50 finder - to med focal length refractors) with a CCD camera which is then connected to the mount (via direct cable and an ST4 port or via software and cable on a PC) and tracks a target star, making small corrections to the mounts positions in order to keep pin-point stars over long exposures.

The next stage up is using dedicated CCD cameras to replace the dSLR, and the use of filters, and often the weight of all this equipment and a decent main scope dictates a decent mount that has both accuracy and load carrying capacity, which normally means an HEQ5 synscan as a minimum, and often an EQ6, both of which cost £750 - £1000 typically.

So a £30 webcam and any scope from entry level costing £150, to.... around £1500 for an entry level imaging rig.... to... well lets just say a top of the range amateur CCD can cost upwards of £5,000. One rig at SGL6 last year would now set you back £30K..... and you can find scopes designed for imaging such as those made by planewave costing upwards of $22,000 for just the OTA (the scope - no mount). OK this is an extreme end of the spectrum, but the point I'm trying to get over is that your original question is too open. You need to stipulate what interest you have, what results you want to get and how much money you have to throw at it !

[kingcarp]

thanks very much malcolm and brian, thats explaned it to me well, i think due to budget im going to get a ed 80 scope to put on my curent motor drive eq2. i will upgrade the mount but as they are so expensive i would rather get better optics for now mainy for veiwing and hopefully some photography at a later date, thanks