Hi steve and welcome to the fun field of astro photography . You will learn lots from the experienced people here .
On your scope , I had one of these a while ago and I loved it
. Great optics on a good mount , and yes the CG4/ EQ3 mount is the standard one , these are a good mount , based on the Vixen mount , a good chinese copy and easily up to holding your 102mm celestron .
Enjoy it as I did , mine , for years , the optics are that good .
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On the pics , keep them small as IIS dont like them to big .
.
Brian.