Celestron SLT EQ mode

[sgazer (Lee)]

I've recently down-sized my setup due to too many other hobbies, kids and general lack of time and energy to do a full guided setup. I now use a DSLR on my Celestron SLT mount. I recently read on this site;

http://www.nexstarsite.com/

that you can put the software from the SE mounts into the SLT (NXS software) and then use it in equatorial mode. I gave it a try as I want to remove field rotation and also having the mount track in one axis only (RA) has got to be more accurate than tracking in two axis (ALT/AZ).

I'm pleased to say the SE mount software works in the SLT mount. I built up a wooden wedge which sits on top of the tripod and attached the SLT mount to that. I set it up last night using using South EQ auto align and all went well, gotos were pretty close and I was able to control the mount using CDC with the Celestron ASCOM drivers. With a very rough polar alignment, I was getting reasonable 2min exposures with a 250mm lens. Later, I realised my polar aligment was way off, dodgy compass, so I'll try again with better polar alignment, and in fact I'll try the Align Master software, as it seems so simple to use.

My plan is only to use my 450d on this mount for imaging, and I've got an 85mm f1.4 lens coming from the US for this (which will require 12x less exposure time than my previous f5 scope), hence 1 minute will be as bright at 12mins on the f5 scope, that's the theory at least.

As the 450d has 12MP, it allows for some significant cropping of the image to cover the area of interest.

Hopefully this quick and portable setup will allow me to get more astro imaging done that I could before.