Moon in Twilight - 28 July 2023

[Mandy D]

I recently bought a Vixen refractor. It is my first refractor, so naturally I was concerned about chromatic aberration, especially as the plan was to image with it. Of course, I was expecting the usual 3 weeks of dense cloud cover that come with any astronomical purchase, so was pleasantly surprised when the clouds parted in the early evening. Once I was set up and had the scope pointed at the Moon, focusing with the single speed rack and pinion focuser was a cinch and I was rewarded with a crystal clear view of craters and rilles along the terminator and began imaging with the D800 at ISO 100 and 1/60s. Viewing the first images, I could see that there was almost no colouration. Bumping up the exposure time introduced the expected chromatic aberration, but at 1/60 the image was already perfectly exposed, so I shot a sequence of images at that. I stacked the best 25% of the 110 images and then processed in GIMP, applying just a tiny bit of sharpening. There is nothing I don't love about this scope and can't wait to try it on the Sun. I think the next purchase has to be a Herschel wedge, but for now I have a Seymour solar filter that fits.

Edited August 2, 2023 by Mandy D

[Franklin]

Nice image Mandy, those Vixen achro's are super sharp, glad you like it and if you use a continuum filter for solar there will be no CA getting through at all. IR cut filter sharpens things up on luna as well.

[Mandy D]

2 hours ago, Franklin said:

Nice image Mandy, those Vixen achro's are super sharp, glad you like it and if you use a continuum filter for solar there will be no CA getting through at all. IR cut filter sharpens things up on luna as well.

Thanks. I'm certainly pleased with the scope. I'm going to RVO tomorrow, so I'll see about getting both of those filters. I'm also looking into a Herschel wedge, which is another reason for getting a refractor.

[PeterStudz]

I like this. The blue colour of the sky/background compliments the moon and gives it a realistic and atmospheric feeling. And you’ve got a nice tint to the moon without it being too dark or too bright. Personally I’m not a fan of the really dark lunar images.

[Mandy D]

@PeterStudz Thank you! I know exactly what you mean and I'd like to do more twilight imaging of the Moon with this scope. Unfortunately, that will have to wait as the Skytee 2 mount has gone back for repair / replacement, so I am without a suitable mount for a couple of weeks.

It is quite funny that you should comment on this image today, as we were talking about you with Ian at Rother Valley Optics this afternoon, or more precisely, about your wonderful Dobsonian mount as we had just bought a Skywatcher 300PDS OTA from them and needed a mount for it! Pictures will eventually follow, but I'm sure it won't be as pretty as yours. Eventually, it will ride on a big AZ.

[PeterStudz]

On 29/07/2023 at 18:30, Mandy D said:

 

It is quite funny that you should comment on this image today, as we were talking about you with Ian at Rother Valley Optics this afternoon, or more precisely, about your wonderful Dobsonian mount as we had just bought a Skywatcher 300PDS OTA from them and needed a mount for it! Pictures will eventually follow, but I'm sure it won't be as pretty as yours. Eventually, it will ride on a big AZ.

Thanks! Somehow I missed this bit of your post until now.

[bosun21]

Nice image Mandy. I also like the twilight sky in the background. A few of the brighter targets can benefit from this, Venus especially so.

[Mandy D]

17 minutes ago, bosun21 said:

Nice image Mandy. I also like the twilight sky in the background. A few of the brighter targets can benefit from this, Venus especially so.

Thank you. Yes, I am just starting to realise this after grabbing this image and now looking for more opportunities.