Diagonal for astrophotography?

[mojorisen279]

If I am buying a refractor tube for AP, do I need a diagonal, or do I just put the CCD camera directly into the telescope?

[Gib007]

CCD camera goes straight into the focuser, no matter which telescope type you use. Of course, if we go into specifics, you might have a focal reducer or field flatenner in front of the CCD camera and shove that into the focuser (there's also filters, OAG, filter wheel, etc) but overall, no diagonal.

[Alien 13]

Hi, you dont need a diagonal but you will need a 2" prime focus camera adapter and a camera T adapter assuming the refractor has a 2" eyepiece fitting.

[Alien 13]

Hi, you dont need a diagonal but you will need a 2" prime focus camera adapter and a camera T adapter assuming the refractor has a 2" eyepiece fitting.

 

OOps i missread the question you only need these for a DSLR

[Ant]

The focus point on a refractor is usually quite a long way out from the focuser, because to use a refractor visually you'll need extra space for a diagonal.

So if you do not use a focal reducer (which will move the focus point in) you'll almost certainly need some way of extending the distance from the focuser to the chip.

I use a FR and a off axis guider and a filter wheel. If I didn't I would need an extension tube.

You can use a diagonal and I have in the past, as it was the only method I had to reach the focus point, but adding another optical element just meant that I lost another little bit of light and it was a potential source of misalignment / vignetting / dust bunnies etc.

Cheers

Ant