Skywatcher 2x Deluxe Achromatic 1.25" Barlow.

[JOC]

I saw that Flo had made an advertisement for one of these.  I looked at the picture and realised that I've already got one, but I'd never taken much notice of how it was described until now.  It says that it is Achromatic.   Now I've still got this ancient Vixen 80's which I understand could suffer from chromatic abberation.   Would it therefore make sense to pop the Barlow in with the 80's kit and use it when I use the telescope?  Do I understand correctly should the Barlow work towards correcting the natural tendency of the telescope?

[Ben the Ignorant]

43 minutes ago, JOC said:

Do I understand correctly should the Barlow work towards correcting the natural tendency of the telescope?

No, the achro barlow would add its imperfection to that of the telescope. Use only apo barlows.

[Alien 13]

20 minutes ago, Ben the Ignorant said:

No, the achro barlow would add its imperfection to that of the telescope. Use only apo barlows.

Never thought of this before, can you get Apo/ED barlows?

Alan

[Ben the Ignorant]

Sure, apo, semi-apo and achro barlows, see the rundown in 365astro's site. Not all ED barlows are apo, and not all triplet barlows are apo, the guys at 365 did an honest listing to guide the choice.

https://www.365astronomy.com/Barlow-Lenses/