29 replies to this topic

[MarMax]

MarMax: That's a great graphic. I can't believe the cameras are that different. Amazing.

Is that from a web-tool?

 

The fov with the 294 would be vast with the small piggy back frac, but that graphic also shows the FOV would be pretty good even with the straight 925, even without reducer for a lot of objects I want to look at. Would probably be even be better with the 925 for small DSO, than with a piggy back scope.

 

Alphatriple: I can see the big FOV would help locate objects. With my aim to do dual visual/EAA the EP view should help overcome problems finding the target, I would hope.

 

Schoolmaster: Excellent point that. With the 925 and an 80mm it would cover both for large objects and the small ones. I think that's convinced me I don't need to go over 80mm.

 

20 Second Subs?

So that just leaves me wondering whether with a reasonable 80mm Frac at say around F6 if I would end up with problems with the limited 20second subs the CPC will allow.

 

And with the cam swapped to the 925 for smaller DSO objects? I suppose a celestron reducer would be essential for those. Would it be enough though with only 20seconds maximum exposure?

Here is the linky to Astronomy Tools. You will use it a lot. 

[MarMax]

Speaking of piggy backing, I'm going to go with the ZS61 on top of the C11 f6 tonight. I had a bit of a fail last night when I could not get a camera to work but I'll just run with the QHY183C up top and the 533MC on the C11. There are a couple of June 2022 Challenge objects I'd like to hit again with a wider field.

 

I could not decide which way to go so I'll stick with the easy way since I've got flats already for the 533/C11.

 

[Leafus]

I know M31 is one of the biggest, and I suspect it wouldn't fit into my longest eyepiece either (if it ever got to a position of the sky I could actually view), but that graphic of School Master really does show how wide an FOV is needed for some objects.

 

The Sub-Question:

Anyone got any comments on how limiting the 20 Second subs exposure limit (I know the max is not quite that simple) will be for EAA with an F5 frac, and the 925 at F6.3?

 

The EVscope seems to get around it pretty well, so it can't be that bad.

 

Or is this a question for a new Thread?

 

Think it is really - I'll start a new one. Thanks for all the help on the Piggy Scope and FOV. Very informative.

Edited by Leafus, 21 June 2022 - 06:17 AM.

[alphatripleplus]

 

Or is this a question for a new Thread?

 

Think it is really - I'll start a new one. 

Good idea.

[SchoolMaster]

I know M31 is one of the biggest, and I suspect it wouldn't fit into my longest eyepiece either (if it ever got to a position of the sky I could actually view), but that graphic of School Master really does show how wide an FOV is needed for some objects.

 

The Sub-Question:

Anyone got any comments on how limiting the 20 Second subs exposure limit (I know the max is not quite that simple) will be for EAA with an F5 frac, and the 925 at F6.3?

 

The EVscope seems to get around it pretty well, so it can't be that bad.

 

Or is this a question for a new Thread?

 

Think it is really - I'll start a new one. Thanks for all the help on the Piggy Scope and FOV. Very informative.

You will likely want to capture larger nebulae, lone North American, and areas like M8 - M20, M17 with other nearby features where max FOV is a big help.