Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - Physicist13

Pages: 1 [2] 3
16
Gallery / Re: widefield distortion corr
« on: 2014 March 16 09:52:20 »
No problem! The seq was get PI to plate solve one image then use that to star generate a new image with around 100 or so stars. Then use that image as the ref image to register all images (dist correct ticked). Then usual processing. Finally did an annotate image to see how well the annotation overlapped the features on the final image.
Patrick

17
Gallery / widefield distortion corr
« on: 2014 March 08 09:05:17 »
I've posted this, not because its a great image, but because  I was really impressed by how PI corrected for distortion. It was with a 50mm lens so FOV is about 20x20deg. The images stars and NGC's, line up with the annotated location perfectly! 11x3min exp, Canon500D,50mm lens at f2.2, mounted on iOptron SkyTracker. (green is cloud that I've not bothered to correct for in this example)
Patrick

18
Gallery / Re: IC2118 The Witch Head Nebula (Mosaic two photos)
« on: 2014 February 12 00:47:33 »
wow lovely!..didnt realise it was that big!..lol, upside down ;)
Lovely dark skies you have!!

19
General / Re: What Capture software do people use?
« on: 2014 February 11 01:05:54 »
For DSLR, a remote timer, simples! :)
Patrick

20
General / Re: distortion correction/modelling
« on: 2014 February 06 04:19:04 »
thanks Andres!

21
General / Re: distortion correction/modelling
« on: 2014 February 06 00:54:13 »
Juan,
Many thanks! that's exactly the info I needed!  :)
Great s/w... sig processsing at its best! ;)
Patrick

22
General / distortion correction/modelling
« on: 2014 February 02 03:02:04 »
I'm getting a bit confused as to how to correct for geometric distortions. I see you can have a distortion correction set in the star alignment. If this is used does the ref image need to be a distortion free image..ie one from a Catalogues Star Generator??
thanks,
Patrick

23
General / Re: Experience with IOptron?
« on: 2014 January 24 04:43:19 »
cld be a "bad" one. some of mine here http://flic.kr/s/aHsjG43Mfq PI processed on NAm neb :)
Patrick

24
General / Re: Experience with IOptron?
« on: 2014 January 23 04:38:08 »
I have one of these. (Skytracker) and use it with DSLR and various lenses. Its v easy to set up and tracking is v good. Its easy to calc how long an exp you can do depending on lens focal length, camera and dec of object you looking at. I find the polar align v good and exp time is limited by the PE, which for mine is about 30arc-sec (p-p)with 8min period.
Patrick

25
General / Re: DSLR with CLS filter preferred method
« on: 2013 December 05 00:37:48 »
Thanks all! phew! DBE,BN,CC was what I was doing  :)

26
General / DSLR with CLS filter preferred method
« on: 2013 December 04 00:45:11 »
I was wondering if there is a preferred method to handle the colour cast from using a CLS filter. I presently let DBE handle it but have seen others use background neut first or channel balancing?? thanks.

27
General / Re: DSLR Settings
« on: 2013 December 03 00:53:16 »
for DSLR always shoot in RAW, so "white balance" is irrelevant.
Pat

28
nice features! TY!

29
General / Re: Evaluating images for noise, signal and more?
« on: 2013 September 11 04:24:11 »
have a look at Craig Starks website (starklabs). He has detailed method to evaluate the noise and gain. Hence you get the SNR out of it.

30
General / cosmic ray rejection
« on: 2013 September 03 08:07:24 »
Came across this. Possibly useful?
Cosmic?Ray Rejection by Laplacian Edge Detection
Author(s): Pieter G. van Dokkum
Source: Publications of the Astronomical Society of the Pacific, Vol. 113, No. 789 (November
2001), pp. 1420-1427
Published by: The University of Chicago Press on behalf of the Astronomical Society of the Pacific
Stable URL: http://www.jstor.org/stable/10.1086/323894 .

Patrick

Pages: 1 [2] 3