I'm planning to purchase an Esprit 100 and ASI2600MC for imaging. I've been doing more research into the use of an off-axis guider and it's raising more questions than answers...
1) My paltry little ASI120MM-S seems like it might struggle with finding guide stars with its tiny little sensor (4.8mm x 3.6mm). Should I be concerned about that? Coupled with the Esprit 100, it would have a resolution of 1.41"/pixel, the same as the ASI2600MC imaging camera since the pixels are the same size, but it would have a much smaller FOV.
2) Is using an OAG overkill for focal lengths of 550 mm or less with an APS-C sensor (~3 degree FOV)?
3) With the SkyWatcher telescopes and a ZWO camera, are there specific OAGs I should be considering?