Barlow or Powermate

[paraman]

This is really a two pronged question related mainly to planetary imaging with my CPC 800 and neximage. I would like to increase the image scale and therefore need to up the available magnification by using either a 3x barlow (currently an ed 2x) or a 2.5 or 4x powermate and maybe swop my prism diagonal with a dialectric mirror variety. On a simple eyeball test my Williams dialectric seems to be a magnitude better on brightness of light transmission than the prism. So I supose the question is, is it worth buying the powermate and dialectric or will the simple upping of the barlow to a 3x be more than sufficient to improve my imaging results?

[Merlin66]

It doesn't come much better than a Powermate!

I ended up purchasing all of them!

Both for visual and imaging they can't be beat.

Ken

[Cornelius Varley]

Powermates are specifically designed for imaging, they also work in a different way to barlow lenses. Read this web page Tele Vue Powermates for an explanation. I suggest that you remove the diagonal from your imaging path, any type of diagonal will degrade the light reaching the sensor.

Peter

[paraman]

Powermates are specifically designed for imaging, they also work in a different way to barlow lenses. Read this web page Tele Vue Powermates for an explanation. I suggest that you remove the diagonal from your imaging path, any type of diagonal will degrade the light reaching the sensor.

Peter

Thanks for the link, it really cleared a few grey areas up for me, I think to be honest that I knew the answer would be the powermate. I can easily remove the diagonal from my williams pair for imaging but with the sct its not quite so easy as anything with any length to compensate for the diagonal being removed is in danger of hitting the base of the unit and of course it makes the initial finding and centering with an eyepiece difficult. I think I have no option but to use the diagonal but hope that the dialectric might have a better transmission to the ccd.

[paraman]

Powermates are specifically designed for imaging, they also work in a different way to barlow lenses. Read this web page Tele Vue Powermates for an explanation. I suggest that you remove the diagonal from your imaging path, any type of diagonal will degrade the light reaching the sensor.

Peter

I bought the powermate, thanks for your help.

Roger

[paraman]

It doesn't come much better than a Powermate!

I ended up purchasing all of them!

Both for visual and imaging they can't be beat.

Ken

So have I, temptation too great and will power too low!