Eyepieces

[ajc0502]

Hi everyone!

My telescope came with 2 eyepieces, a super 25mm and a super 10mm. The other day I was looking at the moon (using my super 25mm and a x2 Barlow as always) and I decided to swap round my super 25mm to my super 10mm and it was a much better image! I could see right into the surface and view the craters inside the craters! Can someone please explain why the smaller diameter eyepiece works better?

Thanks

[Knighty2112]

Are you sure that the reason isn't just because with the 2x Barlow & 10mm EP (effectively a 5mm EP with the Barlow) you are seeing the moon close up more, so more detail is present and the views more stunning? As the moon is very bright it will stand higher magnifications much better than any other objects in the sky. I wrapped up my very brief view of the moon last night with my 2x Barlow and my 6mm EP, which gave me the same view as a 3mm EP. The view was stunning, although I could see the heat shimmer in the atmosphere more at this higher magnification.

[Roy Challen]

The lower the number on your eyepieces, the higher the magnification. Formula for magnification is focal length of scope/focal length of eyepiece.

Eg; 1000/25 = 40 x magnification

      1000/10 = 100 x magnification

Simples!

[ajc0502]

Thanks

[rockystar]

just be careful with the word "better" as it won't always be true. Some objects will look better with an unbarlowed 25mm.

adding to Roy's comment: adding a 2x barlow will double those magnifications, and reduce the Visible field of view.

[ajc0502]

OK, thanks rockystar