ASTROPHOTOGRAPHY

>And would there be a downside to longer, single exposures instead of brief multiple exposures that are stacked?

Make your exposures as Iong as your tracking gear aIIows. You can capture much fainter objects this way.

>>3095714
Haha!
>should be portable enough
Better off Getting an Orion Sirius ED80 EQ-G Computerized GoTo Refractor Telescope
that is more portable and doesn't require colimation like your shitty 9.25" Cassegrain

>>3095888
kindly fuck off, please

Hello my fellow astrotards

tldr do cassegrain need modding to achieve DSLR backfocus?

I own a dobsonian newtonian for visual viewing but I decided to attach my DSLR to it. Turns out it can't achieve backfocus properly so I had to mod the telecope's mirror a few inches up in the tube assembly. It works now and I'm happy with that and all but I was looking at something like OP pic for the DSLR. Do cassegrain telescopes require any modding to achieve DSLR backfocus or will it more or less work out the box?

>>3095895
>colimation

Was his suggestion a bad one? He's right about not needing to spend time on colimation with a Refractor.

>>3095714

>portable enough

The mount alone weighs a metric fuck ton.

>>3095714
i was curious if this thing is worth buying or not http://www.ebay.com/itm/29215250428
what do you guys think?

>>3096379
The Staradventurer is relatively light and can drive 5kg gear. It needs a stable sturdy tripod though, but so fat it is the most portable mount for a small refractor or a super telephoto lens.

>>3097041
Wtf I've wanted one of them for a couple years now I don't get paid for 2 weeks fukkk you!
Ohh me feels bad man that's a good price the other stuff is okay the imager is like what $280 used?

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>>3095888
>Better off Getting an Orion Sirius ED80 EQ-G Computerized GoTo Refractor Telescope
>that is more portable and doesn't require colimation like your shitty 9.25" Cassegrain

So one of these pissy little things can do a better job, costs less but requires a corrector to flatten the field for photography?

>>3098272
Those small refractors are 400-450mm focal lengths, perfect for most DSLR DSO astrophotography. You will need a good newtonian reflector to go for smaller and dimmer DSOs and sharper images, but for starters they are great for sure.

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>>3098278
>Those small refractors are 400-450mm focal lengths, perfect for most DSLR DSO astrophotography.


What about this? It's around 1800mm equiv at f/11. Surely this can be tracked on a sturdy EQ mount?

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The alternative is a SkyWatcher Esprit 150mm Super Apo OTA Telescope with 1050mm @ f/7 - and that son of a bitch sells for $6K+ without a tripod.

>>3098613
Too blurry. Camera lens are not optimized for infinity focus and can only be used without TCs with sharp images. You put a TC on that and the galaxy that was sharp though small before becomes a blurry blob.
Also long focal lengths with refractors become heavy and worse resolution the higher you go, especially CA. Reflectors don't have this problem.