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My DIY pier is 1.8mm high, 200mm diameter and approx 8mm thick.....no gussets, no internal filling. Base has braces welded up the side of the pier approx 400mm. Although it is in an OB's it doesn't have significant protection.....Scope sits in corner of 6m x 6m space and pokes its nose above the roofline about 300mm (so wind is a factor)
Base is dyna-bolted (6x75mm) to concrete shed slab
Sitting on this pier I have an EQ-6 carrying approx 14.5kg.
I have no movement when using that I can see from wind or any other factor.....I have auto-exposure cancel on SGP/PHD2 set at 1.25 pixels and very rarely (if ever) lose a sub......I've recently done almost 100x10 minute subs on a project I'm working on and lost 2 due to a guiding error -
this may not even have been pier related. (925mm focal length on 3.75um pixels)
If i give the top of the pier a hard knock i will get a vibration however it clears up within a couple seconds......by hard knock i mean with force equal to a hard slap/punch
I've said it before and I'll say it again.......I think many people really over engineer their piers and mounting points.
There are many imagers out there creating amazing pictures on a tripod sitting on grass/dirt.......anything bolted down to a concrete slab has to be an improvement!
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