I have prepared a stripped down SimSpec spreadsheet to assist any members looking at designing (or verifying their design) of a SHG.
It will calculate solar disk coverage based on the slit height and the max height of the pixel rows in the CCD.
An estimate of the possible dispersion and final bandwidth resolution is given.
Feedback/ comment welcomed.
SHG design Spreadsheet - SimSpec SHG
- Merlin66
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SHG design Spreadsheet - SimSpec SHG
"Astronomical Spectroscopy - The Final Frontier" - to boldly go where few amateurs have gone before
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- Merlin66
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Re: SHG design Spreadsheet - SimSpec SHG
Good question!
If you had an APO available for the project, then I'd use it, but it's definitely not mandatory.
It would reduce/ minimise the re-focusing between widely separated target wavelengths i.e. CaK Mg and Ha
The wavelength coverage by the typical fast frame camera used in the SHG is only a few tens of angstrom wide and is the equivalent of using a very narrow narrowband filter for night-time imaging.
A normal achromat doublet refocused to the target wavelength works very well.
Hope this helps.
If you had an APO available for the project, then I'd use it, but it's definitely not mandatory.
It would reduce/ minimise the re-focusing between widely separated target wavelengths i.e. CaK Mg and Ha
The wavelength coverage by the typical fast frame camera used in the SHG is only a few tens of angstrom wide and is the equivalent of using a very narrow narrowband filter for night-time imaging.
A normal achromat doublet refocused to the target wavelength works very well.
Hope this helps.
"Astronomical Spectroscopy - The Final Frontier" - to boldly go where few amateurs have gone before
https://groups.io/g/astronomicalspectroscopy
http://astronomicalspectroscopy.com
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer
https://groups.io/g/astronomicalspectroscopy
http://astronomicalspectroscopy.com
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer
- DSobserver
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Re: SHG design Spreadsheet - SimSpec SHG
I also refocus my SHG between Ha and Cak...
Any issue for fluorite treatment Vs Sun light???? I heard about a real sensitivity...
Any issue for fluorite treatment Vs Sun light???? I heard about a real sensitivity...
- Merlin66
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Re: SHG design Spreadsheet - SimSpec SHG
I'm not aware of any significant issues with standard lens AR coatings with solar observing.....
"Astronomical Spectroscopy - The Final Frontier" - to boldly go where few amateurs have gone before
https://groups.io/g/astronomicalspectroscopy
http://astronomicalspectroscopy.com
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer
https://groups.io/g/astronomicalspectroscopy
http://astronomicalspectroscopy.com
"Astronomical Spectroscopy for Amateurs" and
"Imaging Sunlight - using a digital spectroheliograph" - Springer