Sun FD in H-Alpha 5th of March 2021 - both 60mm and 90mm

[arnedanielsen]

Another beautiful day with clear blue skies.

The first image is using the same portable setup that I’ve been playing with for the last few months. This consist of a Coronado SolarMax 60 II w/BF15 filter, Baader 35nm H-Alpha filter and ASI ZWO 178MM camera. Everything mounted on a Sky-Watcher SolarQuest mount.
Stack of the best 60% (1100 of 1835) images captured with an exposure time of 29ms, gain 130 and 30fps. Stacking done in Autostakkert 3, sharpening in AstraImage and contrast stretching in Adobe PhotoShop.

Sun60FD_093734_Ha_(Coronado_60mm_BF15)_20210305_ZWO ASI178MM_lapl5_ap3347_Sharpened_Contrast.jpg (2.09 MiB) Viewed 192 times

The Sun’s altitude is finally high enough to be accessible from my backyard observatory making it possible to also make use my fixed setup consisting of a Takahashi Sky-90 II with SolarMax 90 and BF15 filter, Baader 35nm H-Alpha filter, 2x Cemax Barlow and ASI ZWO 1600MM PRO camera. Everything mounted on a Paramount ME mount.
Stack of the best 60% (457 of 763) images captured with an exposure time of 6ms, gain 0 and 12fps. Stacking done in Autostakkert 3, sharpening in AstraImage and contrast stretching in Adobe PhotoShop.

Sun90FD_121637_Ha_20210305_ZWO ASI1600MM Pro_lapl5_ap8894_Sharpened_Contrast.jpg (4.55 MiB) Viewed 192 times

It’s kind of interesting that for the 60mm f/6,67 need 29ms with a gain of 130 on the 178MM camera to reach a proper exposed image, while for the 90mm f/11,1 need only 6ms with a gain of 0 on the 1600MM PRO to have a proper exposed image. I will have to try and swap the two BF-filters to see if that changes anything.

Best regards,
Arne

[rsfoto]

Hi Arne,

Very good. Can the ASI 178MM be binned ?

[marktownley]

Good disks Arne! Interesting about the 2 different exposure times, definitely try swapping the blockers and see what happens.

[MAURITS]

Nice to see Arne

[arnedanielsen]

Thank you all!

Rainer: I chose the camera for it's small pixel-size and chip size allowing me to to FD imaging with the Coronado 60 with a decent sampling. I haven't tested to use binning so I don't know how good (or bad) that would work. If I need larger pixels I simply swap to my ASI 174MM or PGR GS3-U3-28S4M instead.

Best regards,
Arne