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Ashley beolens
Tuesday 4th February 2003, 21:24
Can anyone tell me if the eye piece of you scope will make much difference to Vignetting, I do not mean magnification, for example I have a 30 W lense, should I be looking for a 30WW instead?

Camberley red
Tuesday 4th February 2003, 21:41
Yes, as the greater the eyepiece magnification the more camera zoom you appear to need to use to remove the vignetting, therefore you'll probably get a much greater angle of view through to the camera using a x20 lens over a x30. The other point is the actuall image size, as the camera lens/zoom/tube configuration makes the magnification very big, this is really noticable when using a cam corder and you have to use high zooms to remove the vignetting, my only experience is with cam corders but still digital cameras must adhere to the same principles. I'm sure other people will have the actual physics behind this effect. By the way I doubt 30w or 30ww makes much difference. The other point is the size of the eyepiece, that's why digiscopers prefer the Swaro or Leica as their eyepieces are very big, this I assume gives the digital camera more image to use and focus on, again reducing the vignetting effects.

hope this helps

Paul

stevo
Friday 4th April 2003, 21:36
Lower power wide angle eyepieces have a greater surface area ie if you have ever looked at say a 60x eyepiece alongside say a 20x eyepiece ,on a lower mag you will see more glass. This greater surface area means that you dont have to zoom up so high (with the camera)to lose the vignetting effect.The ability to set a lower zoom setting on the camera lets more light in & facilitates a higher shutter speed.Hope this helps any techno buffs out there feel free to correct me.

Johnny1
Saturday 5th April 2003, 10:36
I used a 15-45 zoom and had a lot of problems with vignetting, I found the only way to use it was on the 15x setting, even then I had to zoom the camera in to get rid of the black areas. Next I tried a 20x fixed lens which was an improvement, however I'm now trying out an 8x binocular lens which I have adapted to fit the scope, although I havn't taken any pics with it yet it looks promising as there is no vignetting at all.