Help using R5 for astrophotography

[Ozark-Bill]

Hi everyone,

I have used Canon dSLRs for years for doing astrophotography, including deep sky and nightscapes. Over the past couple of years, I have tried to get my R5 involved, but have not been able to solve a problem I am having. The issue is not being able to see enough stars to acquire focus. When using both the back screen and the viewfinder, only the brightest planets/stars will be bright enough for me to see and to use for acquiring critical focus. For something like a wide angle nightscape, this is doable most of the time. However, for shooting deep sky objects, this makes it impossible. I am a low-tech astrophotographer and do not use any type of "go-to" apparatus. So, being able to see the dimmer stars is critical for the star-hopping I need to do to find some of the trickier DSOs that are not visible to the naked eye.

I use very fast lenses and I have tried it both with exposure simulation turned off and on. I assumed this was the issue, but it doesn't seem to make any difference at all. I have also tried using the highest possible ISO settings, thinking this would help with the sensitivity on the screens, but have not had luck with this either.

There must be some setting that I am overlooking, or there is something wrong with the camera. I appreciate any thoughts you'd care to share. 

[johnrmoyer]

I have EOS R5, but am no expert on astro. I have photographed Jupiter and a few of his moons using auto focus.

I have photographed Orion's belt by using manual focus and the manual focus aids in the camera and the viewfinder.

I have used the Canon app on an iPad or an android phone as a remote trigger

Maybe focus manually on something bright like Jupiter, Saturn, or Venus or even a bright star and then move the camera to point in the direction interest?

Focus might change as the camera warms up. Auto focus on a bright star might get it close enough to infinity to autofocus on a dimmer star. I start with center focus area.