Questions on furthering my Imaging

[boggsd]

Hello All!

Last winter I bought a 8" Edge HD w/ celestron VX advanced mount. Now I have the desire to begin autoguiding my set-up, but I am stuck. I thought I could get the orion or celestron 80mm quidescopes but the weight of it in addition to the weight of the scope and counterweight would exceed its weight limit. I've seen a set up where they have an adapter for the smaller finderscope included with the telescope but I've been told it is wildly inefficient for guiding. I've thought to upgrade my mount (the terrible regression of not doing enough research/planning) to the celestron CGEM to allow for the weight but it greatly limits the purchases I can make this year. My intended camera to purchase for autoguiding is the qhy5L-ll for use as guiding and planetary imaging. My limit is 1500 preferably but can be up to 2K. What is your opinions? What's more effective? Will the finderscope/adapter set-up good enough? Anything you guys have seen or used that is cheaper/more effective than what've been presented? Your feedback is greatly appreciated! Thanks!  If you need any more info just ask ( I'm using a Canon eos t2i for deep sky for now )

[PeterCPC]

You can ignore the weight of the counterweight. The AVX will take up to 30lb of instrument weight although you obviously want to keep it well below that for imaging.

Peter

[carastro]

I used a skywatcher finderscope for guiding with a QHY5 and find it works very well.  My finder is a 9 x 50mm and my scopes range between the WOZS71 and the Skywatchers Ed80 and Ed120, what scope are you using?

If it's the one in this link, then maybe the scope focal ratio is a bit high for DS imaging anyway, and it would be cheaper to get a lower focal ratio telescope, otherwise you might need a focal reducer.  I have no experience of SCTs for imaging, so better see what other's think.  

https://grovers.biz/optics/cassegrain/23-celestron-8-edge-hd-advanced-vx.html

Carole 

[ronin]

You should not include the counter weight. So a few Kg saved there.

Not 100% sure why you can ignore it but that is the stated specifications on them all. Max load is excluding counter weight.

[boggsd]

I used a skywatcher finderscope for guiding with a QHY5 and find it works very well.  My finder is a 9 x 50mm and my scopes range between the WOZS71 and the Skywatchers Ed80 and Ed120, what scope are you using?

If it's the one in this link, then maybe the scope focal ratio is a bit high for DS imaging anyway, and it would be cheaper to get a lower focal ratio telescope, otherwise you might need a focal reducer.  I have no experience of SCTs for imaging, so better see what other's think.  

https://grovers.biz/optics/cassegrain/23-celestron-8-edge-hd-advanced-vx.html

Carole 

It's that one in the link; it is quite a high focal ratio for a lot of deep space objects so this winter I will be getting a focal reducer for the telescope (which are quite expensive for the Edge series of Celestron SCT's; I'm not sure why it can't use regular focal reducers)

[boggsd]

Thank you all for the feedback so far! As long as I can ignore the counterweight that allows for so much more flexibility!

[MattJenko]

How about ditching the guidescope completely and getting an Off Axis Guider instead?

[boggsd]

How about ditching the guidescope completely and getting an Off Axis Guider instead?

With an off-axis guider the center of mass will most likely be too far back for me to actively compensate for, the guidescope helps to distribute the weight forward a bit; in the future when I might switch from my heavy DSLR to a lighter CCD I would more likely be interested in off-axis. It just that with the long DSLR adapter made for the Edge it's just puts the center so far back of the optic already but thank you for the suggestion