Solar Filter for Heritage 100P and 114P and Skymax-102 OTA

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Introduction

In order to be able to observe the Mercury transit of the sun in May 2016, I acquired a euro EMC solar filter for my Sky-Watcher Heritage 100P Dobsonian telescope, namely the type SF100 filter (order no. 600-105, size 5: for tubes with a diameter from 103 to 131 mm, aperture = 96 mm). These filters utilize the Baader Planetarium Astro Solar film of density 5 (ND5), which is suitable for both visual observation and projection photography.

Initially, I had purchased a solar filter from the same series for my GSO GSD 680 8 "Dobsonian telescope (order no. 600-109, size 9: for tubes with a diameter from 219 to 283 mm). But I had to order also this smaller filter, because, due to a surgery, I was no longer able to carry my heavy 8" telescope. I therefore had to resort to my smallest telescope, the Heritage 100P, for the observation of the transit. The second filter arrived at my house in time, and I was able to adjust it to the telescope and try it out on a sunspot on the weekend before the transit.

After the Mercury transit, I purchased a Sky-Watcher Heritage 114P Virtuoso Dobsonian telescope that can automatically tracking celestial objects. Although this telescope has a larger tube diameter, I could use the sun filter also on this telescope, if I put the filter holders inside the tube (according to the manufacturer, a certain degree of vignetting will appear in this case). In the meantime, however, I returned the Heritage 114P due to problems with the Virtuoso control.

In summer 2016, I also purchased a Sky-Watcher Skymax-102 OTA (Maksutov Cassegrain), that is, a further telescope tube with an opening of about 100 mm. My sun filter of size 5 fits this tube as well.

Note: The filter has to be carefully mounted to the telescope, so that the film will not be dented by any airlocks.

Note: End of March 2019, I gave away the EMC Sun Filter SF 100, order number 600-105 (size 5), together with my Sky-Watcher Heritage 100P telescope. I am therefore regrettably unable to report any further experiences with the filter size 5 on this site.

Photos of the euro EMC Solar Filter (Size 5)


Packaging of the filter from above		Ditto from below and with included Allen wrench

Filter from below		Filter from above

The filter comes with a small Allen wrench (see photo above right) to tighten the filter holders. It must be noted that the disc-shaped sun visors have to fit properly, so that no sunlight can penetrate through any slots.

Photos of the Heritage 100P Equipped with Solar Filter


Heritage 100P with sun filter		Heritage 100P with sun filter, front view

Heritage 100P with sun filter from the side		Ditto, a closer look

Heritage 100P with sun filter		Ditto

The filter has to be carefully mounted to the telescope, so that the film will not be dented by any airlocks.

Photos of the Heritage 114P Equipped with Solar Filter


The euro EMC sun filter 600-105 is usable on the Heritage 114P telescope if you place the filter holders inside the tube		Telescope with euro EMC sun filter 600-105 in place

Photos of the Skymax-102 OTA Equipped with Solar Filter


Skymax-102 OTA with solar filter- side view		Ditto - from other side

Skymax-102 OTA with solar filter - rear view		Skymax-102 OTA with solar filter - front view

Skymax-102 OTA with solar filter - oblique side view		Ditto

Skymax-102 OTA with solar filter - detail		Ditto, somewhat closer

Mercury Transit 2016 with Heritage 100P

For more information on the transit of Mercury 2016, see page Mercury Transit 2016.

Equipment


Heritage 100P Dobsonian telescope with euro EMC sun filter 600-105 and three eyepieces (32 mm, 16 mm, 6 mm)	We used a blanket to prevent the telescope from overheating during observation breaks	Telescope with camera attached to the eyepiece (T2 adapter)

Ditto from closer	The eyepieces and the rubber plate to separate the adapter rings and loosen them from the filter thread	Moved to another observation location...

Ditto	... and finally to the balcony	In the end, everything was covered with clouds...