Stargazing 2019.003.2 Observing Jupiter with filters
I was set up in my backyard on June 6th, trying out various things, and started observing Jupiter around 11:00 p.m. I think. I’m still getting going with my new eyepieces and layouts, so observed with my 36mm Hyperion 2″ lens, a 25mm super plossl, a 17.3 mm Delos, and a 15mm plossl. Just for fun, I tried playing with the Powermate 2x magnifier with it too, but seeing was way too hazy to pull up anything good. FYI, for alignment, I did a simple three-star Sky Align for the night to get going, and ended up with Regulus, Antares and Denebola.
At super low power, the Hyperion 36mm showed Jupiter relatively clear, moons were easily identifiable. The 25mm super plossl showed me good definition in the bands. But I tried the 15mm plossl (by itself) and played with the Powermate 2x to give me a virtual 12.5mm and 7.5mm power options, all three were too much power for the seeing conditions.
Which left me “best seeing” at 17.3mm with the Delos, with the major bands clear, but the image still pretty watery for the conditions. Nevertheless, it’s a good power to play with my various filters at the 1.25″ size.
I really wanted to test my various filters so started with an Ultrablock and an Oxygen III. Neither are designed for planetary use, and not surprisingly, they turned everything green, killed detail, and reduced the glow so much that the moons almost disappeared. Definitely not winners.
I tried the Variable Polarizing lens, which reduced glow, and the bands POPPED with a dark contrast. I was really surprised, didn’t think it would do squat. It’s not the easiest to adjust and use buried under an EP i.e. it’s one you turn and set, look, take it out, turn and set, etc. But it was really good.
For colour filters, I went through my full range:
- 08 Light yellow — Gentle dimming, good but very pale image;
- 11 Yellow-Green — Even paler than the #8, almost white;
- 12 Yellow — Better contrast, but moons still pale;
- 15 Amber — Light orange, little contrast, and there was a glowing corona around the planet;
- 21 Orange — Bright orange, no contrast, but the moons were prominent;
- 23A Light red — Orange corona;
- 25 Red — Just a red ball, no definition;
- 29 Dark red — Too dark to see much of anything;
- 38A Dark blue — Supposedly this is one of the best to view Jupiter with, but I found it way too dark blue, and the moons were non-identifiable;
- 47 Violet — Just a big purple blob;
- 56 Light green — Green with some definition, but glowy;
- 58A Green — Dim, pale;
- 80A Blue — Light, some contrast, no moons;
- 82A Light blue — Again, supposed to be great, but it was too bright, albeit with some contrast.
I tried the moon and skyglow filter, but it was just dim; the neutral density 25 dimmed it, which sounds good, but there was still a corona. And finally, I threw on the Vblock, which “popped” but it was hard to see sub-bands.
For some reason, I have no idea about my lunar and planetary filter. I’m sure I tried it, and I thought it was really good, but now I’m not sure, as I didn’t seem to record anything.
Overall, from lousy suburban skies, I would say the variable polarizing filter did the best of the non-coloured ones, and I would say maybe the #12 because it had some decent contrast. I’ll have to try it again with some darker skies, and I confess what I really want to do sometime is image all of them to show the difference. But that is a LONG way away at this point. I’ll settle for liking #12 and the VP filter for Jupiter.