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Old 04-06-2016, 10:34 AM
glend (Glen)
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glend is offline
 
Join Date: Jun 2013
Location: Lake Macquarie
Posts: 7,033
Quote:
Originally Posted by bugeater View Post
This camera is looking very convincing. I'll be very interested to see how it goes with different sized filters. Should I ever try narrow band, I'd want to use 3nm filters, but damn they are expensive.
Marty, Jon Rista on Cloudy Nights (post #1404 in the Beta Testing thread) offered this observation about narrowband:

Based on the stacking efficiency charts by Shawnxc, I actually wonder if 300s is more than enough for an ASI with a 7-12nm bandpass. I think for my 3nm filters, I might need up to 600s for OIII an SII. I would actually like to see the same charts that Shawn has produced for the ASI produced for the KAF-8300. So far, I am a believer that 20-60 second subs, depending on sky darkness, are all that is needed for LRGB imaging, so I think the charts model reality well enough to be a good gauge for how long we should be exposing for. It would tell us the sweet spot in exposure time for both cameras.

I use the Baader Narrowband filters (Ha 7nm, OIII 8.5m, and SII 8nm) and they are fine on this camera. Obviously it depends on the target but I find brighter Ha targets like M8, M20, etc are enough with just 60" subs, but agree that OIII and SII can require more time, again depending on the target.

Re filters, most of the beta testers on CN are using 1.25" filters, and they have to be pretty careful about getting the sensor as close to the filter as possible to avoid vignetting. However, I use 36mm filters and there are no concerns.

Last edited by glend; 04-06-2016 at 10:52 AM.
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