C8 SCT maximum FOV possible?

[MjrTom]

Hello all.

I have been looking at picking up a Celestron C8 SCT but after reading my umpteenth review I had a question (well a few) regarding the maximum actual field of view which can be achieved?

The info I have heard so far would suggest that the scopes primary mirror baffle is less than the two inch visual back

Would you experience vignetting with eyepieces which exceed the width of the baffle?

Thanks

[Merlin66]

Assume for your assessment a maximum FOV (with any eyepiece) of just over one degree. If this doesn't meet your needs, you may have to consider other options.

[MjrTom]

Thanks for the info

I suspect that this should be sufficient actual FOV but might need to see with my own eyes before my final decision.

Just to throw the question out there would the C9.25 show about the same FOV with it's larger baffle as the C8?

I know it's focal length is longer but I suspect it will balance out?

[Merlin66]

Yeah, basically the same.....

[MjrTom]

Hmm interesting!

Maybe I should be also considering the C9.25 as well then.

I need a compact scope for DSO viewing, mainly globulars, galaxies and planetary nebula.

I suspect the extra aperture would be advantagious

[Mr Spock]

My C9.25 gets 1.3° with a 42mm LVW (x56, 72°) and is the maximum you can get.

[MjrTom]

Thanks guys

I suspect there might be the odd SCT at peak star party. Better go begging for some viewing time

I guess that 1.3 degrees or 80 arc minutes should be just about enough.

I won't be using it on a GoTo mount so I have my concerns about locating stuff

[andrew63]

It's also an area i' looking at. With my 4" refrac you get spoiled for wide field. And for the same reasons DSO in compact scope a C8 would be a good alternative but a 1 deg or so is a bit limited.

I'm also not interested in goto or guided but was wondering would a EQ5 mount handle a C8 0r 9.25 for visual use only?

andrew

[Merlin66]

IMHO the C8 would be good on a standard EQ5.

I'd suggest the HEQ5 at least for the C9.25....I had my C9.25 on the NEQ6pro - a marriage made in heaven!

[Moonshane]

1 degree is perfectly fine for almost all targets as most but a very small minority are less expansive than this. for the bigger ones you have your frac

[Merlin66]

MjrTom,

The FOV of your average 8 x 50 finder is about 5 degrees...this means if you work close to the centre crosswire you're guaranteed that your object will be in the FOV of a low power eyepiece. From finder to 20mm (on my C9.25) works well. Star hopping with a one degree field takes practise but certainly doable.

You shouldn't have any problems finding stuff...

[MjrTom]

Thanks guys!

Appreciate your replies.

Decision I suppose comes back to C8 or C9.25?

It will be on my Giro III alt/az mount. That should cope with 10kg OTA on each side easy.