Skywatcher Mercury 705

[DC88]

Hi, I'm trying to get together a light weight grab-and-go scope that I can use for viewing the targets from Turn left at Orion. I bought an old Skywatcher Mercury 705, (which is a 70/500 refractor, with a 45deg erecting prism diagonal) and a friend lent me a set of Plossl eyepieces - 32, 15, 10, 9 and 6mm.

Last night, I was trying split Castor and it was barely possible with a 6mm Plossl (a magnification of 83) and image wasn't really sharp enough. Also, a couple of days ago I was looking at Saturn and I could even see the rings clearly.

So my question is what is the weakest link in this set up? It doesn't seem like I will be able to see the Turn Left at Orion objects. Is the erecting prism likely to be poor? 

[happy-kat]

Hi

I think the binocular tagets in TLAO should show.

For comfort of position a 90 degree star diagonal would be next on my list to get hold off.

The seeing last night may not be that good compared to when you saw Saturn. It varies night to night minute to minute.

[Astro Imp]

I was out last night the seeing wasn't the greatest and think you did well at X83 to get any sort of a split of Castor.