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Thursday: Early sunshine has turned into wall to wall cloud! With only tiny blue patches to tease me.
I keep wondering if a "skeleton" OTA would improve my H-a views. All
the important components could be mounted on baffles providing easy
access to individual collimation adjustment. Cooling fans blowing across
critical components like the internal D-ERF and PST etalon?
No doubt paying greater attention to different software would help. Though, quite honestly, I find them increasingly opaque. Simply remembering the meaning of endless symbols and abstract routines is beyond my powers of retention any more. I'm 72 and not getting any younger.
I keep reading that I should be using a mono camera but costs spiral and I'd need different processing to optimise my results. I read how others struggle to benefit from their investment in costly cameras. The point is: I am supposed to be enjoying all this as a hobby. Not making myself feel stupid because I don't understand. Nor remember everything I should. Am I having fun yet? Some of my PROM images do seem to be almost on a par with other imagers who have a dome full of very costly equipment.
A dome is often stated [slated] as providing inferior images due to thermal turbulence through the slit. Any building will collect the heat of the sun. Though I deliberately chose plywood and timber to achieve maximum thermal neutrality. Albeit with a green dome instead of traditional white. Naughty!
A wider slit might help. As would putting the telescope out on an extended veranda out in the fresh air. I tried opening the double doors out to the veranda but it made no difference to the image except to make the dome very draughty. Or even moving house to a less cluttered southerly rural aspect. Our own home lies to the south of the observatory. Short of painting the southerly roof titanium white there isn't much I can do about that.
I just had a mad idea: Paint the shutters and the area around the open slit white. But park the dome with the rear still painted green towards the road. Then the differential temperatures during solar imaging will be lower. Because the white area will only be turned towards the sun when I am imaging. Perhaps not.
The oft recommended
Borg helical focuser seems to have vanished from the European online
dealer's websites. Too expensive compared with all the Chinese
competition?? Leaving only TS who now want 15 Euros minimum for
delivery. They are pricing themselves out of small item, online sales.
So I have ordered a 2" Omegon helical focuser elsewhere with postage only 1/3 of TS' charges. The Omegon offers lots of focusing range so I can probably lose one extender.
The TS short helical focuser was very sloppy even before it fell in half. A single, small pin, riveted into a thin section of aluminium, was the only thing holding it together. Once the pin became loose, as was inevitable as it was rocked from side to side during normal focusing adjustment. There was nothing to stop the pin rising out of its vital, dual purpose location. The threaded portions of the helical focuser then fell apart. A dreadful piece of engineering design! I ought to return it for a refund I suppose.
Pm. After heavy cloud stopped any chance of imaging I took a break until after lunch. Then spent a couple of hours doing visual. I tried out the binoviewer with various eyepieces with and without the 2x WO Barlow in the 7". The 40, 32 and 26mm eps. all provided a full solar disk with room to spare in the field of view. This required I remove the 100mm extension to reach focus. The binoviewer and Lacerta 2" solar prism are effortlessly supported by the FT 3.5 focuser and 2" Baader Clicklock. Even when the binoviewers are sticking out sideways with a pair of 40mm Meade 4000 Plossls.
The WO Barlow provided very large image scale but still nicely sharp on the rippling limb. There was a hint of surface detail but it was fleeting in the thermally disturbed seeing. I had a look in H-alpha using a 90° star diagonal. A few small proms but I didn't push the power any higher than a 20mm ep.
No doubt paying greater attention to different software would help. Though, quite honestly, I find them increasingly opaque. Simply remembering the meaning of endless symbols and abstract routines is beyond my powers of retention any more. I'm 72 and not getting any younger.
I keep reading that I should be using a mono camera but costs spiral and I'd need different processing to optimise my results. I read how others struggle to benefit from their investment in costly cameras. The point is: I am supposed to be enjoying all this as a hobby. Not making myself feel stupid because I don't understand. Nor remember everything I should. Am I having fun yet? Some of my PROM images do seem to be almost on a par with other imagers who have a dome full of very costly equipment.
A dome is often stated [slated] as providing inferior images due to thermal turbulence through the slit. Any building will collect the heat of the sun. Though I deliberately chose plywood and timber to achieve maximum thermal neutrality. Albeit with a green dome instead of traditional white. Naughty!
A wider slit might help. As would putting the telescope out on an extended veranda out in the fresh air. I tried opening the double doors out to the veranda but it made no difference to the image except to make the dome very draughty. Or even moving house to a less cluttered southerly rural aspect. Our own home lies to the south of the observatory. Short of painting the southerly roof titanium white there isn't much I can do about that.
I just had a mad idea: Paint the shutters and the area around the open slit white. But park the dome with the rear still painted green towards the road. Then the differential temperatures during solar imaging will be lower. Because the white area will only be turned towards the sun when I am imaging. Perhaps not.
The oft recommended
Borg helical focuser seems to have vanished from the European online
dealer's websites. Too expensive compared with all the Chinese
competition?? Leaving only TS who now want 15 Euros minimum for
delivery. They are pricing themselves out of small item, online sales.So I have ordered a 2" Omegon helical focuser elsewhere with postage only 1/3 of TS' charges. The Omegon offers lots of focusing range so I can probably lose one extender.
The TS short helical focuser was very sloppy even before it fell in half. A single, small pin, riveted into a thin section of aluminium, was the only thing holding it together. Once the pin became loose, as was inevitable as it was rocked from side to side during normal focusing adjustment. There was nothing to stop the pin rising out of its vital, dual purpose location. The threaded portions of the helical focuser then fell apart. A dreadful piece of engineering design! I ought to return it for a refund I suppose.
Pm. After heavy cloud stopped any chance of imaging I took a break until after lunch. Then spent a couple of hours doing visual. I tried out the binoviewer with various eyepieces with and without the 2x WO Barlow in the 7". The 40, 32 and 26mm eps. all provided a full solar disk with room to spare in the field of view. This required I remove the 100mm extension to reach focus. The binoviewer and Lacerta 2" solar prism are effortlessly supported by the FT 3.5 focuser and 2" Baader Clicklock. Even when the binoviewers are sticking out sideways with a pair of 40mm Meade 4000 Plossls.
The WO Barlow provided very large image scale but still nicely sharp on the rippling limb. There was a hint of surface detail but it was fleeting in the thermally disturbed seeing. I had a look in H-alpha using a 90° star diagonal. A few small proms but I didn't push the power any higher than a 20mm ep.
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