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Tuesday 13th 10.am, 54/50F. Bright sunshine with thin cloud. Not so cold overnight. I pulled off the insulating dewshields to discover the objective lens was wet on all three surfaces! Front, back and even between the elements. Only the front surface responded to the hair drier. The rear and interstitial dew became much worse!
I wouldn't dare leave a dew band running all night because of the fire risk. In fact I couldn't use my heating strips anyway because the Hitechastro control box I was sent has a cigarette lighter plug. I don't have any power supplies with a matching socket. I've had to order a 12V PS with a suitable socket online.
10.45 Here I am an hour after setting up and still can't get a sharp image!
11.42 Another hour later: First sharp[ish] image but very uneven lighting. Then solid cloud!
12.23 Another image. I have been struggling with thin, obscuring cloud and dew all morning. It was all but impossible to get a sharp enough image to be sure of best focus.
My 6" iStar objective with interstitial and internal dew. The ugly
smear between the elements doesn't look good! It obviously wasn't
cleaned very well! I tried warming the cell and main tube with the
hairdrier but it made no difference. It took over an hour for the dew to
shrink to coin sized. I may make an access door just behind the
objective for the hair drier. Though that won't help with the dew
between the elements.
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