|
Wow,
what a can of worms you have cracked open. If have owned both and imaged with both. Here are my thoughts.
The fork mounted SCT are great for Visual Use in ALT/AZ. For imaging you obviously need a wedge. Polar aligning a fork mount has always been harder and taken longer than EQ mounts(at least for me). You need to spend a LOT of money on a quality wedge eg Milburn Wedge etc.. if you want decent imaging results when fork mounted. The cheaper Meade wedges tend to sing like a turning fork. The plus for imaging is that you can image through the meridian and not worry about mounts strikes. The problem is most SCT’s have mirror flop which means when you pass the meridian you get a clunk which = ruined exposure….
Another issue with fork SCT’s in Polar mode is that imaging near South Celestial pole is almost impossible with todays large imaging trains (the new Meade RCX’s get around this problem with longer form arms)
Most of the fork mounted SCT’s aka Meads and Celestrons suffer from high or unpredictable Periodic Error, which makes imaging at native f/10 a VERY difficult task without the use of devices like SBIG AO7. Many imagers are using their SCT’s with wide field piggyback dopes like the ED80. The y image through the ED80 and guide via the SCT with great success. Its all about cost and expectations. To get a 10 inch scope like a Meade LX200 into an affordable package some compromises must be made. These compromises are often in the quality of material, tolerances in bearings, precision in machining etc…. Don’t expect Gendler type pics from a stock form mounted SCT and you wont be disappointed….
A decent EQ mount is miles ahead in stability and damps out vibration much quicker, but then again tends to cost about he same as a complete SCT fork mounted package. The added benefit of EQ’s is that you are not limited to one OTA but can change OTA’s depending on what you are looking at or imaging and the seeing conditions. I don’t own a fork mount anymore as I tend to spend more time staring at computer screens than eyepieces. If I wanted a visual platform I would probably get a good DOB with an Argo Navis.
My 2 cents worth….
Best regards
Chris venter
|