[ATM] about solar filters

["Treur, Harro" <H.Treur@wlb.amsterdam.nl>]

Dear astro-experts,
I would like to adapt my 12,5" f4.8 Newtononian in order to see the upcoming
Venus transit.
1 - In what way shall I filter the sunlight? I have an old piece of
Solarscreen but this gives a lousy low contrast. (I much prefer the
oldfashioned eyepiece-filter, though dangerous. It gives a wonderful
contrasty image!). I heard about the homemade Baaderfilter. Is this the same
as Solarscreen? Or is Baader much better. 
2 - Is it possible to give the telescope some corongraph-like features to
see the ring of light of Venus while entering the solar limb? What's the
best place to block the direct sunlight: in the eyepiece? 
3 - I was thinking about stopping the telescope with two holes opposite of
each other, to create higher resolution. Mel Bartels advised me to do four
holes, to obtain a highter resolution in all directions. My question: should
I bother about higher resolution? (Maybe it is better to use only one hole
of 100mm. Four smaller holes could probably create four shifting images
caused by bad seeing because of the heating effects of the sunlight...)
 
friendly greetings,
 
Harro Treur - Netherlands

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