I've been working on a new configuration for a while and it is making sufficient progress at this point to post an image and get some feedback. The configuration is my ASI6200 camera with a Canon EF200mm f2.8 lens piggy backed on my Tak TSA120/QSI683 combination. The TSA120 is performing the role of guide scope whilst imaging with the ASI6200. See attached image of the hardware configuration.
I purchased the Canon lens adapter from Astromechanics (Russia) to mount the 200mm lens on to the ASI6200 camera. This adapter allows for the direct control of the focus motor and aperture setting in the lens. I've been using the SGP Pro auto focus routine to directly control the focus on the lens. The driver for the lens adapter also allows for the setting of aperture and this was stepped down to f5.6 with a view to reducing coma around the outside of the field.
The vital details for the image are:
* ZWOASI6200 camera
* Canon EF200mm f2.8 lens @ f5.6
* 24 subs, Ha @ 1200s, Gain 100
For those unfamiliar with the ZWO ASI6200 camera, it a full frame CMOS sensor with small (3.76 micron) pixels. This makes for a challenging time in setting up one's image train as it will very quickly show up any optical or mechanical aberrations that are present.
Subs were taken around full moon time so some work was required to remove gradients.
A quick process in Pixinsight thus:
* Calibration and cosmetic correction
* Registration
* Integration
* A quick denoise routine
* Gradient removal
* Stretch with histogram and curves
I've uploaded the image as full frame, uncropped with two versions, the full 9576x6388 frame and at a 50% reduction in resolution for 4788x3194 pixels.
Click here for full resolution.
Click here for 50% resolution.
One of the main challenges now is to know when to stop fiddling and start taking images. With the ASI6200 it is difficult to get the spacing and tilt spot on. On the other hand however, the large field and small star size mean that one has to pixel peep to greater depths when hunting down any ugly bits that may be present. It is a case of getting things to a point where the final image quality is acceptable for 'normal and reasonable viewing' (whatever that is)
.
I would be interested interested in the thoughts of others on this forum on the above and any feedback upon viewing of the posted results.
Clear skies,
Rodney