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Should i use a Barlow lens instead of drizzling in lack of focus length and aperture?

Acquisition Drizzle Deep Sky Coma
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Haakon Rasmussen avatar
Haakon Rasmussen avatar
Due to the immense cost of buying a new telescope with larger aperture and focal length,  i am using the Bayer/transX drizzling  technique instead. Question is: Would it be better to use a coma corrector with 1.5 magnification (from APM)? The seeing in the south west part of Germany is mostly bad i understand. I am using  a color camera with the IMX571 sensor (pixel size 3,76) with a telescope with 800mm focal length ratio F4.

Or is there nothing to gain, when the aperture stays the same? Or could it be that i loose  details using the drizzle technique?
I hope someone could shed some light on these thoughts.

CS Haakon
andrea tasselli avatar
andrea tasselli avatar
Haakon Rasmussen:
Due to the immense cost of buying a new telescope with larger aperture and focal length,  i am using the Bayer/transX drizzling  technique instead. Question is: Would it be better to use a coma corrector with 1.5 magnification (from APM)? The seeing in the south west part of Germany is mostly bad i understand. I am using  a color camera with the IMX571 sensor (pixel size 3,76) with a telescope with 800mm focal length ratio F4.

Or is there nothing to gain, when the aperture stays the same? Or could it be that i loose  details using the drizzle technique?
I hope someone could shed some light on these thoughts.

CS Haakon

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You would gain potential resolution only if you're under-sampling the PSF. If, as you say, the seeing is mostly crap where you are then there is nothing to gain by either drizzling (not CFA drizzle) or increasing the focal length (which would also make everything dimmer for the same integration times). Even CFA drizzle ( I assume you're referring to this) comes at a cost of signal loss so you need to thread carefully there too. Otherwise,if you can afford the extra integration times, you'd be better served with a longer focal length.
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Haakon Rasmussen avatar
Haakon Rasmussen avatar
Thank you, Andrea!

I will perhaps try the APM 1.5 Barlow Coma Corrector lens.

CS Haakon
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