Over the last couple of years I have conducted some experiments to determine what my imaging system could capture compared to a fast imaging system such as Mike Sidonio's. I have found that whilst my system performs well on distant objects such as galaxies where I get quite good detail and good contrast, it really struggles when it comes to imaging outer halos on planetary nebula such as IC5148 and NGC3132 and things like the optical jets on NGC1097. I put this down to two things. Firstly, the slower focal ratio would and does have a significant impact on gathering those photons. Secondly, the sensor tech I have is aging and impacts also.
This image is composed of 45 hours of integration with 30 hours in Ha. The outer chevrons are barely visible in the colour image and even viewing the Ha data itself shows only the barest of signal. This is despite doing subs at 20 minutes, which should be near optimum for my system. I had considered doing 30 minutes subs but was concerned about the core detail being totally blown out.
What this shows is that to get similar detail to a 12" f3.8 system I need to image about 6x or more the amount of hours for any channel to get similar detail on these very faint outer halos.
Feel free to comment and discuss.
Click here for larger resolution image.