Objective lens : D = 50 mm f = 170 mm ( F = 3.4 ) achromatic lens
Eye piece : 3 lens in 2 groups ( better than kellner )
I set black piled seal inside of the tube .
Inside of the tube
small hole for eye piece and the plate to attach on the tripod can be seen .
That black piled sheet gives much better image than before .
I can get clear viewing even on daytime .
I also made ocular by myself using scraped lens from broken binocular .
construction : Hood ,cell , objective lens , main tube with the plate , ocular