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First (Video) Light with TS/GSO 8"/F4 Newt


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Finally "bit the bullet" and gave the 8"/F4 Newt + Watec, an outing. Observatory still a (cuss inducing) mess of cables and many things STILL to get to grips with... Gain settings, Gamma settings etc. At least the mount was (vaguely) Polar Aligned! I really need to write stuff down or something - What extension tube is needed, did I use a focal reducer etc. Indeed some of the following would have been far BETTER (e.g. less Coma?) if I'd remembered to *remove* the focal reducer... :)

I AM rather pleased with my "M1" though. The (focal reduced) MAK150 gave good results on clusters etc. But, for the first time, I sense the Aperture/Speed of the Newt was beginning to pay dividends. As ever, I tend to "overcook" the processing, but one begins to see the "tendril" structure in M1 maybe? A better choice of image scale, next time... :)

Aside: M42 seems to be quite a "difficult" subject - Nebulae, generally? I tend to just "whack up the contrast and hope for the best", with the more stellar-like objects! LOL. Some nice (Video typical?) "Black Halos" around the stars though... :)

M37

m37.jpg

M1

m1.jpg

M42

m42.jpg

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Hi

Some nice pictures - M42 is difficult to get the exposure right - if you get the nebulosity, you tend to over cook the trapezium stars.

I have not noticed the black halos around stars on my SDC435 - might be an artifact of the in-camera processing - have you got the sharpness set very high?

What have you used to capture the video?

Clear skies

Paul

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Thanks Paul! :)

The black halos are certainly "known artifacts" in video astronomy? Interestingly, there is a "solution" to M42 too: Short exposures... long exposures... "unsharp masks" etc. ALL of this described in Massey & Quirk's Book. BUT, "so many settings, so little time"? And there was me not wanting to get into "serious" imaging. :)

Aside: The capture device is an "EasyCap" (genuine?) Generic Dongle thing... :)

Edited by Macavity
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Looking good its a nice image size with that set up.

You have a bit of fisheye in there that'l be your extension tube/nosepiece on the camera maybe a bit too long between camera and reducer. Shorter focus scopes need shorter nosepieces on the camera.

Philj

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You have a bit of fisheye in there that'l be your extension tube/nosepiece on the camera maybe a bit too long between camera and reducer. Shorter focus scopes need shorter nosepieces on the camera.
Interesting thought, Phil. It does look a bit more "fish-eye" than coma? <G> The reducer is actually one of these:

Opticstar C/CS to 1.25" Low Profile Adaptor.

A fine thing (probably!). In the quest for "greater reduction", I *had* actually spaced it further away from the sensor, with an extra C/CS ring. More "tests", more "notes" of settings, I sense... :)

Edited by Macavity
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Nice images - I particularly like M1.

Are these single 10 sec integrations or stacked images?

They're stacked. In this case 250 frames processed, rather arbitrarily, though Registax, wherein I also fiddled with the Gamma - Turned up higher value Wavelets etc. I hope, unlike CN, we will not dictate that images can't be [stacked] though. [teasing] :)

For the sake of argument, I extracted a single frame:

m1_single.jpg

I recall the above was using the maximum integration, but at modest gain. Gamma was off (probably)? As you can see (tilt your LCD screen?) M1 is a LOT fainter - Sending variable numbers of light quanta(?), from time to time! The Watec is, just about, picking up "thermal noise", showing the odd hot pixel etc. :)

Much experimentation still needed with settings? Image scale. Notwithstanding "darks", "flats" etc.

Enough to keep me going for quite a while... :)

Edited by Macavity
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That's what these cameras excel at - seeing more than you do with the eye.

You can capture and stack, but it's the immediacy of seeing the image real time that I like.

I guess you could try DSS Live - have SHARPCAP save every Nth frame to a folder and get DSS live to monitor and stack every picture in that folder - live view and almost real time stacking.

However, once you have used a monitor and not a laptop, you will really begin to appreciate the ease of use.

Clear skies

Paul

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I have had a go with DSS Live and Astrovideo with my Watec. Both work very well. However, although it's possible to stack images 'on the fly' I do feel like I'm spending too much time fiddling with settings and changing directory etc so I spend less time than I'd like actually looking at the image on screen!

I also tried out a couple of monitors (both CRT according to the back of them - they were certainly large enough!) but so far my lap top provides by far the brightest image. Not sure why that is because I thought a CRT was meant to be better.

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