New 80mm objective lens

[SkySurfer]

Hi all, and a merry Xmas to you all

I have had a slight accident with my ST80 refractor that I use for guiding, to cut a long story short the objective lens is badly damaged, after a major clear out of my astro gear.

As I now need a new one I wondered whether it would be possible to get a new objective lens for the scope, but maybe a much better quality one, like an APO, so I could then use it for wide field,

imaging too, rather than buy a complete new scope with an APO lens.

I have already upgraded the focuser to a new heavy duty silky smooth one, so it would seem a Shame to have to just get rid of.

Amy ideas of suppliers here in the UK that I could purchase such and item....??

Best regards

SS

[John]

I think you would need to use an 80mm F/5 objective lens for the light cone to work within the tube and baffles of the ST80 and there are very few apochromat scopes that have that specification. The Skywatcher ED80 would be a great replacement but that is an F/7.5 objective lens.

You might be able to source a replacement ST80 achromatic objective lens by placing a "wanted" advert on the UK Astro Buy & Sell website:

http://www.astrobuysell.com/uk/

I have a feeling that it might be more cost effective to get a used ST80 and put your nice focusser on it but you never know, someone may have a damaged ST80 with a good objective that they don't have a use for.

Another alternative would be to buy a used ED80 which can be picked up for as little as £150.

[John]

PS: I R Poyser sell some objective lenses and say that have others available. It might be worth giving them a call:

http://www.irpoyser.co.uk/index.php?page=120

[ronin]

One of the Chinese manufacturers used to advertise a few ED lens but cannot locate the one, I suspect they have been removed from their websites.

You will need another 80mm f/5 and then you will have to hope that the lens cell fits in the ST tube - no guarantee of that.

Think Intane have some but not 80mm f/5 so no good and no idea how you could get one over here anyway.

You need to check ones line GSO, Barsta etc that a retailer is known to deal with as then they could possibly get one in with their next order.

I checked the APM site but again couldn't see one (might be somewhere) but they are EXPENSIVE.

[ronin]

http://www.surplusshed.com/pages/item/l2196.html

No idea about how to get it sent to the UK.

Seriously suspect a used ST80 is the better option an move any bits over.

[russ.will]

It's an ST80 that cost's what? £65 second hand?

Much as my recycling side hates to say it, bin it and buy another one. The ST80 is the cheapest way to get an 80mm F5 objective. If you were to spend the money required for a better objective, you'd probably want better mechanicals than an ST80 to house it in. Half decent wide-field scopes need not cost a lot more.

Russell

[Jim Steele]

Astroboot have a St80 on their specials page for £90 at the moment if you want a like for like...