Piggybacking on CPC925

[Rumbold2010]

Hi All, 

Hope everyone is safe and well and at least getting some clear skies to use whilst we are all stuck at home. Just a quick question - if there is any anecdotal experience then all the better. 
 

i have a much loved CPC 925 and whilst it’s good at many things, it’s F10 credentials don’t exactly scream DSO imaging so I’ve decided to put my Canon 60Da to work piggybacked on the CPC Mount. My question is this - assuming the use of a 135mm lens ( I’ve just invested in the Samyang 135mm F2 and about Astronomik clip in CLS filter ) how long do you think I could reasonably expect to get away with by way of subs tracking in Alt-Az mode? It is my intention to ( eventually ) invest in a new EQ Mount and second scope at which point I’ll move the camera over but in the meantime, I’ve got what I’ve got....

All advice/ thoughts much appreciated

Clear skies!! 
 

Andrew