Astrophotography Setup

[Stub Mandrel]

On 26/01/2021 at 13:30, Daf1983 said:

Would the 80ed not need a focal reducer to make it quick enough for imaging? This would bring the focal length to 510mm (with 0.85 reducer which most use), which is not that much longer than the 72ed. I'm not disagreeing with you by the way, just trying to get my head around both optiins😁

I've had a play on the field of view simulators, and while the 80ed is probably better for more targets, I felt there wasn't much in it(assuming you use a focal reducer)

Bear in mind the ED72 will need a flattener as well so if used with the SW flattener the relative lengths remain the same.

I have no trouble imaging small, faint DSOs at F8, personally I don't find that aperture makes as huge a difference as I would expect, but it's affected a lot by other aspects of your setup too.

 

<edit> I should make it clear the primary reason for a 'reducer' is its role as a field flattener and improving star shapes - changes in focal length are a 'side effect'.

 

Edited January 27, 2021 by Stub Mandrel

[Daf1983]

14 minutes ago, Stub Mandrel said:

Bear in mind the ED72 will need a flattener as well so if used with the SW flattener the relative lengths remain the same.

I have no trouble imaging small, faint DSOs at F8, personally I don't find that aperture makes as huge a difference as I would expect, but it's affected a lot by other aspects of your setup too.

 

<edit> I should make it clear the primary reason for a 'reducer' is its role as a field flattener and improving star shapes - changes in focal length are a 'side effect'.

 

I was initially thinking of pairing the 72ED with an OVL flattener (which doesn't alter the focal length), but after the advice I've received on here, I'm swaying heavily towards the 80ED. I think I will use it without a flattener/reducer to begin with, and keep an eye out for a second hand reducer while I save some pennies. It's good to know that some imaging can be done at it's native speed of f7.5. 

I'm not expecting to get amazing results to begin with, so am happy to take the time to get used to the mount, while I save for some guiding equipment and a reducer.

Thanks again for your advice

[Vilius]

On 26/01/2021 at 15:33, 7170 said:

PM sent with details of the one I bought, incase directly linking publicly here on the forum to a product is not permitted.

@7170, could you send the details my way too? I'm buying the same rig and also wondering about power.