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Daveskywill
09-03-2014, 12:27 PM
Hi Yall:

I'm trying to do astrophotography and need to learn about the finer things

like even guiding and stuff / because now I've got my wonderful new Nikon D800

DSLR camera at 36 megapixels and feel I need a newer nicer bigger scope than

my older 10" Meade LX200GPS.

However I'm perplexed because I only have ~$200 to spend now. And only receive ~$700 per month on which most it takes to live on and no job.

Also I don't know if I'd like to build my own. I'd really love to build from

a bare blank the whole thing mirror and all. And one time tried with out

success building a 20" F5 Newt reflector.

PS: it would be nice too if it could all fit into a 10'X10'X6' roll-off-roof.

So please consider that.

Too I'm kind of spoiled :) by my LX200GPS in all its deluxe features.

Like if I were to buy a Meade Lightbridge 16" there wouldn't be

any tracking motor. And would need to put it on a ~44 degree wedge

for this latitude to point north. Any ideas if I went this way? and rig

up it's own track motor to lengthen the timed exposure my ND800 could

do on it?

PPS: my Nikon D800 has that out-of-focus look on most of its images.

Some say that it needs better lenses?

Thanks.

glend
09-03-2014, 01:34 PM
I would stick with the Meade LX200GPS and see what you can do to upgrade it here and there. Forget aperture fever on your budget, enjoy what you have.

Wavytone
09-03-2014, 08:58 PM
You have a lot to learn, grasshopper. As Confucius say: Those who bite off more than they can chew are destined to choke.

Try grinding, polishing and figuring an 8" f/5 mirror first to understand what is involved before attempting anything larger.
Maybe then a 13-14" thin mirror at f/4.5 if you are confident and (a) the 8" was well polished and (b) has a good figure.
Only then try a 20".

Once you understand what is involved I suggest you will quickly realise why no-one makes mirrors by hand anymore, that died out 20 years ago when the Chinese entered the market. There is a good reason why you see unused large blanks coming up for sale on places like Cloudynights.

FWIW I have made a 6" f/8, 4" f/3.5, 8" f/6 and a Ramsden eyepiece, long ago.