Solar Observing Resumes

New Barlow Lenses

I resumed solar observing on a cool, breezy April 22nd, after more than 5 months of cold, clouds, and obscured lines of sight. It took a long time to set up my equipment since I was out of practice. Much time was wasted trying to figure out why the telescope mount was not connecting with my computer. I finally realized the reason. The power strip was not turned on! Ugh! How could I be so dumb? The computer cannot recognize a dead mount! Although seeing was not very good, I did manage to obtain some respectable images.

A nice pair of prominences hung above the Sun's limb.

Prominences (Click for full detail.)

One major sunspot group, designated 1726, was also visible. The following three images show 1726 at three increasing magnifications made possible by two Barlow lenses in use for the first time. The lowest magnification was obtained with a new 1.5X Barlow which barely, barely reached focus with all elements in the optical path pushed in as far as possible. The highest magnification was obtained with a new 5X Barlow which gave a very nice frame-filling view, but requires steadier seeing to show sharper detail.

Sunspot group 1726 imaged with 1.5X Barlow lens (Click for full detail.)

Sunspot group 1726 imaged with 2X Barlow lens (Click for full detail.)

Sunspot group 1726 imaged with 5X Barlow lens (Click for full detail.)

Notice the annoying parallel curved interference fringes in the last image. These are caused by multiple reflections somewhere in the optical path. I still haven't figured out how to get rid of these. The edges of features are a bit fuzzy due to poor seeing.

One other smaller sunspot 1727 was accompanied by a curved filament.

Sunspot 1727 imaged with 1.5X Barlow lens (Click for full detail.)

Sunspot 1727 imaged with 5X Barlow lens (Click for full detail.)

The magnified1727 image above is a bit sharper than the previous magnified 1726 image. An inverted version of the 1727 image highlights the floating nature of the curved filament and the depressed aspect of the sunspot.

Floating filament near sunspot 1727 (Click for full detail.)

I'm looking forward to more observing sessions in the coming months when the weather is warmer, the seeing is better, and the Sun approaches the peak of its activity cycle.