Going solar. Simultaneous H-alpha and White Light!


Good Friday was a clear and sunny day with few clouds until after lunch: 

My first real solar time with H-alpha and White Light, under a clear sky. 

My 150mm/ f/8 [working at 120mm f/10 equivalent] and 90mm f/11 side by side. 

The detail is mind blowing in H-alpha. With the fine texture of the prominences clearly visible.

There was even a bright surface feature showing altitude variation near the limb. Several, very small dark spots on the surface too.

In white light the sun was simply featureless.

I started off crunching about [very carefully] on an inch of snow inside the observatory as I mounted the telescopes. The ice and snow weren't melting. So I opened up the southern curtains to let the sunshine in. The eyelets are simply held by projecting, round head screws. So they are very easy to open when needed.

The mounting isn't quite balanced even with both OTAs on board. The 5 kilo weight inboard on the Dec shaft is still slightly too much. The stepper motors struggle to lift a load uphill. So I slacked off the clutches to try and balance everything. It really need an outboard sliding weight on a bar somewhere on the OTAs to manage longitudinal balance. This will aid the balance around both axes. 

All this will change when the 7" refractor is added. I just need to fix the other two OTAs onto the largest. Usually this is easily managed by stacking hinged tube rings. A bit of distance between the various eyepieces is useful to avoid collisions. The same goes for focusers.

It was fun having a chance to use the AWR drives. With four correction speeds, as well as the different drive rates it is very satisfying to be able to move slowly around the sun's disk looking at prominences. Rotating the IH2 [handset or paddle] in one's hands soon avoids confusion over direction of travel. This only occurs when the diagonal is at an odd angle for comfortable viewing.

Click on any image for an enlargement. 


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