darker contrast in eyepieces

[red dwalf]

would i be right in thinking that the smaller the aperature of an eyepiece the better the contrast will be ?

i don`t mean aperature i mean field of view, will get my head round all this terminology L.O.L.

[michael.h.f.wilkinson]

I am not sure what you mean by aperture of an eyepiece. As the focal length becomes shorter, the background darkens, but so do extended foreground objects. Point sources stand out more because they do not get smeared out (until you hit silly magnification). The diameter of the rear element of en eyepiece has very little to do with the contrast (a lot more with the field of view and immersion the EP provides).

[red dwalf]

i was compairing a 21mm eyepiece with a 13mm the 13mm looks a darker view when looked through in daylight, just wondering if this was a "normal" thing when compairing

[michael.h.f.wilkinson]

At short focal lengths, magnification goes up, so the same amount of light is spread over a larger solid angle. Therefore the image is darker.

[red dwalf]

Right get it now, Thanks Michael for that.