Ioptron skytracker + Shorttube 80?

[Lognic04]

because the ioptrons maximum weight capacity is 3.7kg,and a shorttube 80 + my eos 700d is 3 kg i was thinking i could put an orion shorttube 80 on it to get some extra reach compared to my 250mm lens, it is 2 degrees difference so it is pretty substantial. i was just thinking because i would like to be able to at least make out some smaller details, also my 250 lens has pretty crazy vignetting at the long end (55-250) and min apeture is f/5.6. also most of the larger objects will still fit, exepting l,s mc and rho oph.
:shrug::shrug::shrug::question::que stion::question:

[pluto]

I used to put my PST+QHY5L-II on a Skytracker and it was ok but I'm sceptical you'll be able to do any kind of long exposure with the ST80 + 700d.

For example I can just get good 30-60 second exposures with my WO71 + A7s on a SW Star Adventurer and, while your scope and camera weigh less than mine, it's a much sturdier mount (and counterbalanced!) and a much larger FOV per pixel.

If it was me I'd probably just look for a nice second hand manual prime lens, which should be a lot better than your zoom. If you can get a Canon FD to EF adapter maybe you can get something like this (http://www.ebay.com.au/itm/Exc-Canon-New-FD-135mm-f-2-8-f-2-8-Lens-149320-au-/322243125274). Or if you can get a Nikon ai lens to EF converter, like this (http://www.lightinthebox.com/massa-massa-mount-adapter-ring-for-nikon-ai-lens-to-canon-eos_p805590.html?currency=AUD&litb_from=paid_adwords_shopping&utm_source=google_shopping&utm_medium=cpc&adword_mt=&adword_ct=84539756114&adword_kw=&adword_pos=1o1&adword_pl=&adword_net=g&adword_tar=&adw_src_id=1810908567_303095234_217 69258874_pla-156605397434&gclid=CjwKEAjwuo--BRDDws3x65LL7h8SJABEDuFRthDkwjkTwyJ ian2MblnwH74rhEEk9Wsr0qyWOocA_hoCEK jw_wcB), then you can get something like this (http://www.ebay.com.au/itm/Exc-Nikon-Nikkor-200mm-f-4-f-4-Ai-Lens-771177-au-/322238837710).
I've used similar FD and Ai lenses, with basic adapters, on my A7s and they can be quite good - especially for the money.