long or short focal lenth

[star_chaser]

650 mm (25.59 in)

this is the stats from my scope ,ive tried searching but i have no idea as i would like to try my hand at imaging soon and ive been reading up and im bit confused is long focal lenth better for planets . as i have no idea about whats long or short

thx star

[rowan46]

you are looking for something called the focal ratio which is the focal length divided by the objective. for imaging dso's youre looking for focal ratio nearer 6 for planets, 10 or over is better. I think

[Capricorn]

Whats the aperture?

Actually what is the scope and the mount?

650mm isn't a lot to go on.

If the scope has a dia of 130 then it is f/5 if 90mm then f/7.2 if 70mm then f/9.2

If you are thinking of imaging then be prepared for expense.

[star_chaser]

aperture 130mm(5.12in) focal lenth 650mm(25.58in) focal ratio 5 mount eq (md)

ok this is the full specs sry to be a pain and keep asking. but just as i think im starting to understand something well i realize that im not .

i would like to use webcam laptop for imaging our solar system first.

thx again star

[rowan46]

f5 is considered a fairly fast scope you should consider using a barlow or 2 for webcam imaging, hope this helps

[jgs001]

It's a bit short really for the planets (but I'm using a 600mm refractor), you'll need to use, a barlow as said, you could stack them up (barlow's multiply so 2, 2x barlows is 4x) or use a couple of tubes to move the camera away from the barlow to increase the image scale. This has the benefit of not adding any more glass to the system.

The f/5 means it's good for deep sky type imaging, but that has it's own pitfalls and can be a lot more expensive.

You don't mention what mount you have the scope on, which makes it tricky to advise on what you might be able to get out of it.

[star_chaser]

thx for the replys i was looking to try taking pics of dso untill i see the price so im gonna start this way and see where it goes.do you think this scope will be ok for lunar/planets.because i always wanted a scope and just bought this one drunk (spur of the moment thing)but now i have it hey why not have a go

i have the celestron astromaster130eq/md

AstroMaster 130EQ-MD (Motor Drive) Telescope (item #31051) / AstroMaster Series Telescopes / Telescopes / Products / Celestron.com

and thx again star

[jgs001]

I'm not sure how accurate the motor is for tracking, give it a try and see, you may find you'll be surprised. I think long term, the tracking of the mount may get challenging, but it's defo worth a shot. The drives on my NexStar SLT was pretty good for shortish exposures on Deepsky.

[ollypenrice]

F5 is fast.

A focal length of 650 is short.

As that stands you have a good optical spec for long exposure deep sky imaging, not planetary.

But no worries, a Barlow or two or Powermate (expensive) will take your effective focal length up to 2 or 3 or more x the native 650. I would start at 2x to learn the ropes.

In webcam imaging you don't need good tracking, really, because in a sense you add the tracking at the end. You stack a thousand or more images in Registax (free) and the software aligns and then combines them, correcting any drift on the mount that way.

For deep sky imaging you do need a very accurate mount and a lot of other stuff. Start with a lottery win if possible...

Olly