Revelation ED 2x Barlow 2"

[milkyjoe]

Hi.

I'm thinking about buying one of these, but would like some thoughts on it first please? I will be using it with my dslr, but also for viewing too.

Thanks.

[sixela]

Pretty good barlow.

[Egor Blimey]

Me too, or the Skywatcher version which is more expensive. I seem to remember a post on another forum confirming that Revelation barlows were the same as gso in America, which in turn were highly regarded.

I want to be sure that I'll not be beyond the focus limit using the 2" diagonal in front of this barlow though, on my Skywatcher 6" f5 refractor.

[blinky]

Why do you want to use it with a DSLR? If you do you will need to quadruple your imaging time to gather the same number of photons. Visually it will do the job fine and if you start imaging the planets with a webcam it will also be fine but I have never had any success using a barlow with a DSLR

[milkyjoe]

Why do you want to use it with a DSLR? If you do you will need to quadruple your imaging time to gather the same number of photons. Visually it will do the job fine and if you start imaging the planets with a webcam it will also be fine but I have never had any success using a barlow with a DSLR

Do you not need to use a barlow to increase magnification when doing astrophotography work, I cannot see how else I would do this otherwise?! :-\

[blinky]

You can use a barlow to do this but most folks dont bother. I would say, start imaging and enjoy what you get with your setup - dont worry too much about increasing magnification at first. As I said earlier a barlow doubles your focal length but that means to get the same exposure you would need to quadruple your exposure time and this puts a lot more pressure on your alignment and guiding.

[milkyjoe]

I see, but sticking my dSLR to the end of my scope is only going to give me a limited number of objects I can photography, right?! :-/

[RikM]

I have never had any good results with my DSLR and a barlow. I use the camera direct on the scope and then crop the area I want out of the final image later.

Rik

[blinky]

I see, but sticking my dSLR to the end of my scope is only going to give me a limited number of objects I can photography, right?! :-/

Dont worry about that - you have a whole universe to photograph. There will be plenty of objects for you to image before you need to worry about longer/shorter focal lengths.

[sixela]

Do you not need to use a barlow to increase magnification when doing astrophotography work,

Well, usually you either do planetary astrophotography and then you just get a webcam (and then you do use a barlow) or you do DSO photography, but then you usually snap pictures of objects at the image scale corresponding to prime focus, and tend to change scopes or sensor for another image scale (because if you just use a barlow, because of the higher f/ratio, you have to expose for a lot longer to get the same S/N ratio).