Quote:
Originally Posted by Steve14
I was hoping for some advice on getting a daystar quark so i can attach it to my 102mm F5 apo refractor for solar imaging. I'm worried that i may not achieve focus as it has an inbuilt 4.3x barlow. The back focus of the scope is 80.3mm.
Daystar recommend either not using a diagonal or using a focal reducer if there are issues. However, i'm unsure if this will resolve any potential problems and i don't want to buy the quark only to find out i cant use it. Is there a way to figure it if it will come into focus based on the telescope and filter specs?
PS i'm aware that i have to use an UV/IT cut filter for telescope apertures larger than 80mm...
Thanks for any assistance.
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You only need a blocking filter before the diagonal and do not need any front mounted one on scopes up to and including 120mm as long as it is not an oil spaced doublet/triplet
I have no problems with focus
FROM Daystar Instruments
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On Wed, Feb 27, 2019 at 10:46 PM Tiffany Messerschmidt <tiffany@daystarinstruments.com> wrote:
Jeremy,
It is correct to say a front mount ERF is not needed with a 120mm refractor.
.