80mm Refractor - v - Cannon Lense

[MeSeany]

I want to get involved with deep space astrophotography - Ive read about the great things a William Optics 81-GT can do - but are there any Cannon DSLR lenses out there that would match it.

Im thinking weight - abiltiy of the lens to and camera to merge very well as 1 unit etc etc

Any thoughts on the best approach?

[lensman57]

I read your thread about which scope? I would suggest that you have a look at the SW ED 80 first before jumping at the deep end. As for Canon lenses for AP there are a few that are suitable but with regret these are all L lenses and with the exception of the 200L F2.8 and the 135 L F2 which are about the same price as the GT81 the rest are somewhat very expensive. These lenses also are not as well corrected as a made for purpose ED or Apo but with a bit of care can produce decent results for widefield imaging.

A.G

[MeSeany]

I read your thread about which scope? I would suggest that you have a look at the SW ED 80 first before jumping at the deep end. As for Canon lenses for AP there are a few that are suitable but with regret these are all L lenses and with the exception of the 200L F2.8 and the 135 L F2 which are about the same price as the GT81 the rest are somewhat very expensive. These lenses also are not as well corrected as a made for purpose ED or Apo but with a bit of care can produce decent results for widefield imaging.

A.G

Thats a very good point - Im going to focus on Jupiter for now using my 8" Newt - then try some limited DSO with the dslr + dslr alone on my mount - like you say lots to do before I look at a 80mm

[lensman57]

Thats a very good point - Im going to focus on Jupiter for now using my 8" Newt - then try some limited DSO with the dslr + dslr alone on my mount - like you say lots to do before I look at a 80mm

I think that you are on the right track and to be honest a DSLR on your 200P will give you a slightly larger FOV than a 314L with an 80mm F6 even with a 0.8X reducer and this is the combination that a lot of us are using.  Don't forget that the SW CC does have a reduction ratio of 0.9X so your FL will effectively be 900mm.

Regards,

A.G

[MeSeany]

I think that you are on the right track and to be honest a DSLR on your 200P will give you a slightly larger FOV than a 314L with an 80mm F6 even with a 0.8X reducer and this is the combination that a lot of us are using.  Don't forget that the SW CC does have a reduction ratio of 0.9X so your FL will effectively be 900mm.

Regards,

A.G

Sorry - what combo are you guys using the 80apo with reducer?