Object Details:

Although I've been using various wavelengths for Deep Sky Objects (e.g. h-alpha, Oxygen III & Sulfur II), h-alpha for solar, and occasionally even 'narrowband' (e.g. DSO style) h-alpha filters for lunar and 'white-light' solar imaging (e.g. in an attempt to improve the seeing as longer wave-lengths tend to scatter less than shorter ones), I had not before tried any 'specialized' wavelength filters on the planets. Therefore, the attached composite is my first attempt to use such filters on Jupiter. 

Starting with a 'normal visible' (luminance - IR/UV cutoff), from left the shots were taken using an Infrared, Ultraviolet, Methane and once again a Luminance filter. As is somewhat common, when utilizing 'specialized' filters, greyscale versions of each are included in the second row. Although Jupiter only reached an altitude of 26 degrees above our southern horizon and the seeing was fairly poor that evening, I was fortunate to catch the Great Red Spot while it was rotating on.  

Generally speaking, when used on Jupiter the IR filter allows for greater penetration of the haze resulting in an enhanced contrast of small details; the UV enhances the cloud structures, while the methane (i.e. absorption) shows higher features in the Jovian atmosphere, with more methane appearing darker (and thus indicating lower) while little or no methane appears brighter (and thus indicates higher features in the atmosphere). 

Image Details:

Taken by Jay Edwards at the HomCav Observatory on the morning of June 26, 2020. Being aware that the filters would attenuate the image, but not knowing to what degree, I kept the optical system used as 'photographically fast' as possible while still trying to maintain a reasonable focal length to provide some level of detail. 

Therefore, the attached were shot at the prime focus of a (vintage 1970) 8-inch, f/7 Criterion newtonian reflector using an ASI290MC plaentary camera / autoguider. This scope is mounted on and tracked with a Losmandy G-11 running Gemini 2 control system. 

Processed quickly using a combination of AS3, Reistax & PSP, given that these test shots turned out reasonably well, I'm looking forward to trying these filters again as we approach Jupiter's opposition next month, and if possible will add a barlow lens to increase the focal length / magnification.

Copyright: Jay Edwards