Celestron Astromaster 130mm- buy a used one or not?

[Sidd]

Hello Everyone,

Posting after a long time. 

I am trying to upgrade my current telescope. The reason for upgrading is to get a bigger aperture. Although I would like to try my hands on photography but that is not necessarily the reason for the upgrade. I might want to image but perhaps not for now. 

So my current scope is a humble Meade Polaris 76mm 700 FR 9.2 reflector and the one I am eyeing is a used Celestron Astromaster 130mm 650 FR 5 reflector. It is with a bloke who wants to sell it. The price is somehow OK I would negotiate a bit so that is not the question here. 

I need suggestions on the following two areas:

1. General performance (would it be a good upgrade for viewing only? What differences in terms of observation to expect. Would jumping from 76/700 to 130/650 be of benefit in terms of clarity and detail? IF yes, to what extent?

2. The condition of the scope is such that the small red dot finder is repaired and looks bad aesthetically however it is fully functional. I can live with that. The rest of the scope if fine. OTA is perfect the EQ mount is good it comes with a motor on the mount which works fine and has accessories kit with a couple of extra lenses and three filters (not expecting much from filters though) but that is what is there. The only thing that is a bit off putting is the primary mirror. Although I have had a peek and saw the moon and a star its collimated and there is nothing wrong with eh view. But then, when I put a flash light to the primary I could see something strange. The mirror is dark tinted but from the outer edges it was transparent white as if the tint is some kind of coating that is coming off. Strange to me. the owner has no idea for he never had issues and never looked inside. However, if it is the coating that is coming off (5 years of use) and if I buy it I was wondering if in another three years it might come off more ??? There is a bit of dust on it too but that's not a problem. What is happening here ???

I am in Pakistan where telescopes are not easy to come by. We need to import an item and with duties and all it doubles the price. Getting it taken here is also out of question because I cannot bother anyone with such huge luggage. So what to do in this situation. Should I sell mine and wait for months and try to see if some other scope gets available or should I go with this purchase???

Any insight / suggestions is welcome.... Thanking you all in anticipation. 

[Ricochet]

1 hour ago, Sidd said:

1. General performance (would it be a good upgrade for viewing only? What differences in terms of observation to expect. Would jumping from 76/700 to 130/650 be of benefit in terms of clarity and detail? IF yes, to what extent?

Going from 76mm to 130mm should show quite an improvement. Quantitatively, you're looking at almost double the resolution and being able to see stars almost two magnitudes dimmer.

1 hour ago, Sidd said:

But then, when I put a flash light to the primary I could see something strange. The mirror is dark tinted but from the outer edges it was transparent white as if the tint is some kind of coating that is coming off.

Where was the light? Pointing down the tube and illuminating the front of the mirror, or behind the mirror shining through it? Did you get any photos of the problem that we can see?

How far in from the edge of the mirror was this coating degradation? A mirror coating will degrade over time and it is likely to start from the edge. If the issue is only a few mm into the mirror, then what you could do is to make a black card ring that can sit either on the mirror itself, or on top of the mirror clips, and mask the damaged area. 

[Sidd]

Thanks for the response sir. Will keep this in mind.