The natural celestial objects nearest to earth are of course those found in our Solar System. Closest to earth is the moon, which gives stunning views, even at the lowest modest magnification. The sun (see figure 2) is the closest star to earth. Light only takes 8 minutes to arrive here. Using the Lunt LS80THA nice images can be made of the granulation on its surface and of the solar flares (protuberances) around the edge. Currently (2018) the sun's activity is at its lowest point, resulting in a rather dull view with only minor protuberances and an occasional sun spot.

In March 2019 I experimented with the Lunt to improved the quality of the images taken through the Lunt. From another Dutch amateur astronomer I learned to improve my processing. Although the Sun is still quite dull, having something in the foreground makes the image much more attractive. Just above the cockpit a small sunspot can be seen, while above the left wing a protuberance can be spotted.

Ever since InFINNity Deck became operational the sun was quite boring, only occasionally showing some activity. That changed a few weeks ago and now it starts to be interesting again as can be seen in this image. The large sun spot at the right is number 2741.

Recently I received a M42 to 2" adapter for the blocking filter of my Lunt. This adapter allows to include a barlow in the optical path. On 29 July 2019 I tested it for the first time using a TeleVue 4x PowterMate and ZWO ASI174MM. A movie of 10,000 frames was shot in 40 seconds, processed in AutoStakkert using sharpening and finally enhanced, colourised and sharpened in PSP. In the lower left corner the Earth is shown at scale.

On 20 September 2019, with the assistance of two high school students, we imaged the sun around 08:45am UTC. Imaging was done using the Lunt LS80THA in combination with a 4x PowerMate and ZWO ASI174MM, focusing was done manual. In 2 minutes time 2584 frames were captured, 30 percent of which were stacked. Some processing in AutoStakkert, IMPPG, and Paint Shop Pro resulted in this rather pleasing image. The Earth has been added to the image at the same scale.

On 25 May 2020 a nice prominence was visible, captured again with the Lunt LS80THA with a 4x Barlow and ZWO ASI174MM.

In June 2020 I learned a new technique of solar imaging processing. Using ImPPG it is possible to invert the histogram, a method I explain in more detail here. Using this method allows to show more surface detail and protuberances.

The image was taken with the Lunt LS80THA and ZWO ASI174MM monochrome camera.

On 30 and 31 July 2020 a nice long protuberance was visible at the sun. Imaging was done on 31 June with the Lunt LS80THA in combination with a TeleVue 4x PowerMate and ZWO ASI174MM. During 60 seconds 7k frames were captured 10% of which were stacked using AutoStakkert. Post-processing done in PSP.

That same day I also captured the Sun in full. During 2 minutes 4809 frames were captured, 30 percent of which was stacked using AutoStakkert!. Stretching was done using the inverted method in IMPPG, post-processing in PSP using the method described in my second article on solar processing.

Slowly but surely the Sun it showing more activity. On 9 November 2020 sunspot AR2781 was well visible and imaged using the Lunt LS80THA. Adjacent image is taken with the ZWO ASI174MM camera directly mounted on the blocking filter (so without Barlow). Processing was done using an inverted histogram.

Using the SkyWatcher Esprit 150ED and a white-light filter, sunspot AR2781 was imaged in full spectrum.

Using a TeleVue 4x PowerMate behind the blocking filter of the Lunt LS80THA, sunspot AR2781 was imaged in some more detail.