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View Full Version here: : Full size solar filter or offset solar filter- filter size question for Meade 14”


h0ughy
10-02-2012, 10:35 AM
Just a question – would I be better of with a full aperture solar filter for the Meade 14” or an off axis 6” version? I am happy to gain some advice from people who have experience in solar viewing/imaging on this point? :question:

mswhin63
10-02-2012, 10:48 AM
I have one for and one against for 1/4 aperture.

For: - My DSLR was shutter had to be set to 1/1000th to take a reasonable image. My webcam required filters to reduce the light level, and that is with a 1/4 aperture on my 12" DOB. Imagine what would happen if I had a full aperture.

Con: - Only slight issue and not really a problem, the line up of the CCD and CMOS needed to search for the sun. This was tested with a full aperture Finder scope solar filter and found this to be a problem when I set up the filter in different quadrants on the secondary section of the DOB.

h0ughy
10-02-2012, 11:06 AM
ah ok point taken

h0ughy
15-02-2012, 08:08 AM
when there is not much difference in price for the filters should i go for the full aperture version?

Satchmo
16-02-2012, 06:55 PM
you need to consider the exit pupil situation.

For daytime solar observing your pupil will probably be around 2mm or less. If the typical seing handles only say 50X then you will not gain resolution in anything over 100mm aperture.

Merlin66
16-02-2012, 10:56 PM
The 150mm will show all that needs to be seen.
(I have a full aperture filter for the 12" Meade...used it twice in about eight years! The 4" refractor, however, shows more detail than I'd hope to record and is much easier to use)

h0ughy
16-02-2012, 11:04 PM
thanks. i made a decision earlier today as it was only 20 dolars diffrence in price. i ordered the full dia version, but i can easily step it down