Quote:
Originally Posted by Suzy
Fabulous idea Chris!
And a very nice package too. 
Just one thing I'm not sure of..
That 7mm ep and 3x barlow suggestion of yours.
The ones that come with the scope are a 10 & 25, sometimes a 15mm. Well, with a 3x barlow using it on a 7mm ep it goes beyond both the practical (300x mag) and theoretical (480x mag) limit of the scopes ability- bringing the 7mm eyepiece to 515x mag  .
My suggestion is to replace the 7mm with a 15mm and replace the 3x barlow with a 2x barlow.
If it was a 2x barlow, you can magnify the 15mm down to 7mm. That's a nice sweet spot on planets at the focal length of 1200mm which those 8 inch dobs are. And the 10mm can come down to 5mm barlowed.
Just my 2c worth.  |
Very good points Suzy,
The 570x mag of the 6.3 mm and the 3x barlow would not be used, the idea was from the fact I have one of those 3x ED barlows (ED = Extra Low Dispersion) and it works very well on my scope in combination with my 10mm EP giving me 300x (my scope has a 1000mm focal length).
Your idea of a 2x is a better fit overall, I have found however, that barlowing on a planet visually is not as clean and crisp as a smaller focal length eyepiece only which is why I suggested that 6.3mm to give 190x (about the max for the scope) and nice and clean....
Thanks for the ideas, it's all about what works best for the beginners and I appreciate your input
Cheers
Chris