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Old 26-04-2016, 11:32 AM
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ChrisV (Chris)
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Join Date: Aug 2015
Location: Sydney
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Originally Posted by CrazyGiza View Post
A quick question... Alex mentioned an eq platform for his dob 8inch. Is an eq platform absolutely needed for vidastro with a dob, even goto?
I was all but set on 12gotodob, i would like good ep views, but i would like the ability to drop a camera in as well. 50/50 timeshare, eyepiece or Ln300 (or cheap equivalent).
- There's a few out there doing video with a dob alone, no EQ or ALTAZ mount, but not many. More using 80mm achros such as ST80, or small newts/MAks/SCts. You might need a bit of focal reduction on a dob/SCT/MAK as the cheaper CCDs are small, 1/3". Bigger glass doesn't = much better image with video. Its all about focal length.
- If you want to shift to such a mount - GOTOs just make life easier. Then you can do all the observing and controlling from inside on a monitor or a computer. And spend more time observing.
- If you get GOTO or a motorised mount an EQ mount is not essential. Most people use ALTAZ mounts as they are easier to set up. If you use a sensitive camera such as the LN300-type then is short exposures especially if you have focal reduction.
- Also many (including me) now run analog cameras though a frame grabber (or use a USB camera). Then you do short exposures 5 – 20sec and stack them in something like sharpcap which aligns, reduces noise etc. Again most use ALTAZ mounts with this just because they are easier.

Originally Posted by CrazyGiza View Post
Ken Ballaratdragon's 4 or 5 second exposures with refractor on utube, is it doable on gotodob?
Should i reconsider the dob? Can someone suggest a scope for dso, vid and ep?
I don’t use eyepieces so shouldn’t comment, but will.
I use an 8” SCT for smaller objects (with f6.3 or f3.3 focal reducer) and have an 80 APO for wider field.
For a cheap foray into videoastro a lot of people use (1) 6-8" f4/5 imaging newts (like the GSOs) on GOTO mounts. (2) 80-100mm achro refractors (see ken Dragonman’s advice on using those), even an ST80 gives beautiful wide-field video (on a manual mount). I'm told the problem here is you need an imaging newt to get it into focus - so that might make eyepieces difficult.
To get video and EPs maybe an SCT is good or a MAK. A few use 5-6” to great effect.
The big boys use 8-10" SCTs on ALTAZ with heavy focal reduction or hyperstar and get amazing stuff. But they are also using $1.5-2k cameras such as the Ultrastar, Infinity, ASI1600 etc. Watch some of their live broadcasts.

Originally Posted by CrazyGiza View Post
Moon and planets are cool, but ya get a good enough eyefull of those with everything. So 85% dso, 15% moon and planets....i know i know, ya cant have it all.
DSOs a killer with video - full beautiful colour pics as Alex showed. Big nebulae great, galaxies take a while to sort out but great.
Moon is fun with video.
But planets - stick to your eyepieces. Have sent a PM.

Cheers Chris
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