I've had the Carbon Fiber version of this scope (no longer available) for four years. It uses HOYA FCD1 extra-low dispersion (ED) glass. The newer version of this scope uses HOYA FCD100 glass, and is reportedly sharper... but it's also $700 more expensive.
Visually, I found my ES102CF to be extraordinarily sharp. On nights of very-good seeing, I have cruised the lunar surface at 212X without any difficulty at all. For visual use with the diagonal, the addition of one of the included extension tubes is required. This need for the use of extension tubes for different visual or AP equipment-applications is typical of almost all modern refractors.
For AP, by the way, I would suggest that you also get the ES Field Flattener:
When used for AP with the Field Flattener, the addition of two of the included extension tubes is required.
These extension tubes screw together. For AP, in conjunction with use of an ES 2" 2X or 2" 3X Focal Extender, I have to use four of the extension tubes... and they still exhibit no flexure whatsoever, that I have been able to detect... contrary to GIFTED1570's assertion. Perhaps my older scope's focuser is different than the one that's used on this current aluminum-bodied version... but I don't believe so. Might be worth an e-mail to ES tech support, however.
Your 500D is a couple ounces heavier than my Olympus E-M1... but not significantly heavier. With the E-M1's additional battery-holder and a wireless remote shutter-release attached to it, it weighs about 1lb 11oz... and my ES's focuser handles the weight easily.
You didn't mention what mount you'll be using for AP. The aluminum-bodied version of this refractor is two-and-a-half pounds heavier than my carbon-fiber version... so for AP, be sure that you'll be using a mount that will solidly handle the total combined weight of the refractor, the finder-scope, the camera, the attachment pieces... and possibly a guide-scope and guide-camera as well.
As an example of what this scope can do, this is a single exposure of the Moon (be sure to click on it), taken with my Olympus E-M1 and an ES 2" 2X focal extender (the original of this photo is two-and-a-half times the resolution of this one, which has been reduced, to comply with C-N posting regulations):
These four-element focal extenders also act as field flatteners, by the way... so no additional field flattener was used (or needed).
Hope this helps!