just wondering what kinda effects barlowing has on wide angle eyepieces. When barlowed to they still keep their wide angle or does barlowing take them down to a 'standard' fov?
No using a good barlow will only change the magnification not the aparent field of view of the eyepiece but unless the clear aperature is not large enough in the barlow you may get vigneting.
The actual (seen through the eyepiece) field of view of the sky will become smaller as the magnification goes up but the eyepieces designed apparent FOV should stay the same. eg a 55 deg plossel will stay 55 degs .
Using barlows and low power eyepieces this way is great for spectical wearers as it allows the longer exit pupil distance of lower power eyepieces but at a higher magnification from the barlow.
Using a good quality barlow will actually improve eyepiece performance by reducing astigmatism at the edge of field and allow simpler designs to work better in faster optical systems.
What may happen thou is the exit pupil distance may be come a bit to long resulting in finding it hard to keep the eye at the correct distance for the eyepiece.
Televue powermates don't change any of the charecteristics of an eyepiece and are a step up from a barlow.
Interesting to note that most if not all Televues eyepieces have built in barlows in the eyepiece. There not just 2x barlows bolted on but vary and are designed to complement each eyepiece FR and are a permanent part of the optical train.
This is part of the reason why they perform as well as they do.
Barlows of years gone by were pretty nasty and gave the telenegative amplifier (barlow ) a bad reputation but todays better quality designs and glass have made them a worthy tool to have .
