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Old 26-04-2016, 11:32 AM
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ChrisV (Chris)
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Quote:
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.

Quote:
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.

Quote:
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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