Which Barlow

[Alienfox]

I have a very cheap S-W Barlow lens that came with my telescope and I think it's time for an upgrade, I am look for a 2 or 3 times as I now want to capture some images of the planets, your recommendations would be appreciated.

[JB80]

What sort of budget do you have?

[russ.will]

Something like the GSO/Revelation 2.5x 3-element apo Barlow is sensible money at £31.99.

It does vignette with my TV 25mm Plossl, but given the small image circle required to actually encompass a planet and the small chips webcam type cameras have, this shouldn't be an issue.

Russell

[JamesF]

Definitely agree with Russell.  It's an excellent barlow, especially given the price.  And if you want a bit more power you can always add an extension between it and the camera.

James

[michael.h.f.wilkinson]

For planetary imaging you need to get up to F/15-F/25 at least. As your scopes are F/5, that means 3x-5x Barlow. The advantage of the ordinary Barlow lens is that you can vary the magnification by varying the distance to the chip or EP. For imaging, tele-centric Barlows are recommended for their better image quality. They do not allow great variations in image scale however. Tele-Vue PowerMates are such tele-centrics, as are the Meade TeleXtenders (no longer sold under that name, but now marketed as Bresser SA Barlows), and Explore Scientific Focal Extenders. The 3x and 5x would fit your needs well. They are quite a bit more expensive, however.

[Alienfox]

Thank you guys, I have a budget of about £50, Just been reading write ups on the GSO/Revelation, it looks good value so will probably buy one later today.  Thanks.