Recently Browsing 0 members
No registered users viewing this page.
I made an acquisition and processing tutorial a while back (3 years ago? Yikes!) and it is fairly dated in terms of what I'm doing these days. I've been asked for a long time to make a new one showing what I'm doing these days. Specifically how I'm processing a single shot image for both the surface and prominences and how to process them together to show prominences and the surface at once. I've abandoned doing split images and composites and strictly work from one image using layers. Acquisition does not use gamma at all anymore. Nothing terribly fancy, but it's not exactly intuitive so hopefully this new video will illustrate most of the fundamentals to get you started. Instead of an hour, this time it's only 18 minutes. It's real time from start to finish. I'm sorry for the long "waiting periods" where I'm just waiting for the software to finish its routine, it lasts 1.5 minutes and 30 seconds tops typically at first. The first 4 minutes is literally just stacking & alignment in AS!3. I typically will go faster than this, but wanted to slow down enough to try to talk through what I'm doing as I do it. Hopefully you can see each action on the screen. I may have made a few mistakes or said a few incorrect things or terms, forgive me for that, this is not my day job. I really hope it helps folk get more into processing as its not difficult or intimidating when you see a simple process with only a few things that are used. The key is good data to begin with and a good exposure value. Today's data came from a 100mm F10 achromatic refractor and an ASI290MM camera with an HA filter. I used FireCapture to acquire the data with a defocused flat frame. No gamma is used. I target anywhere from 65% to 72% histogram fill. That's it! The processing is fast and simple. I have a few presets that I use, but they are all defaults in Photoshop. A lot of the numbers I use for parameters are based on image scale, so keep that in mind, experiment with your own values. The only preset I use that is not a default is my coloring scheme. I color with levels in Photoshop, and my values are Red: 1.6, Green 0.8, Blue 0.2 (these are mid-point values).
Processing Tutorial Video (18 minutes):
RAW (.TIF) files available here to practice on (the same images you will see below as RAW TIFs):
Video for Acquisition, Focus, Flat Calibration and Exposure (20 minutes):
(Please let me know if any links do not work)
Results from today using this work flow method.
SSM data (sampled during 1.5~2 arc-second seeing conditions):
Equipment for today:
100mm F10 Frac (Omni XLT 120mm F8.3 masked to 4")
Baader Red CCD-IR Block Filter (ERF)
PST etalon + BF10mm
SSM (for fun, no automation)
I scrapped all the Oiii and Sii data I previously took during a full moon (about 15 hours worth) and retook it all when the moon was a bit smaller at 76%. Ha was taken during 98% and 67% moon. All the lights were taken on the following nights: 12th, 19th and 20th September 2019.
Integration times, all in 600s subs unbinned:
Ha = 28.33 hours
Oiii= = 5.67 hours
Sii = 5.67 hours
The Ha data is really nice, and unsurprisingly the Oiii and Sii is not as strong (or nice).
I'm missing that (vital) step in my processing routine of getting the Sii and Oiii properly stretched to match the Ha, before combining. I dont really know how to deal with the weaker data properly. Any pointers would be appreciated.
What I do currently:
All the data is loaded into APP into separate channels/sessions.
The data is stacked and registered against the best Ha sub
This produces individual stacks of Ha, Sii and Oiii that are all registered
Each channel is processed with DPP in APP and then saved as a 16bit TIFF
Each is opened in PS
Stars removed with AA and any remnants removed and tidied up
I then open a blank RGB document in PS
I paste Ha into Green, Sii into Red and Oiii into Blue
Adjust the selective colour settings to get 'Hubble palette'
Adjust levels, curves, saturation until looks ok
All the Ha Sii Oiii data is then combined together in a single 'super' stack in APP using quality weighted algorithm to create a 'luminance'
That luminance layer is adjusted using levels, curves, and NC tools such as local contrast enhancement and deep space noise reduction (using masks to apply as required)
The luminance is pasted onto the above colour layer, and incrementally added using gaussian blur
Cropped and saved.
Here it is anyway I haven't intended on any more exposure time for this one, but will consider it, if the expert opinion dictates otherwise!
THIS ITEM HAS NOW BEEN SOLD.
This listing is for my personal narrowband filters (Kayron from Light Vortex Astronomy). They are the Astrodon Hydrogen-Alpha (HA), Oxygen-III (OIII) and Sulphur-II (SII) 3nm 1.25" narrowband set. These are considered the highest-end narrowband filters money can buy, able to produce images of exceptional quality and incredible sharpness, cutting through a vast amount of light pollution. The 3nm variants featured here are fantastic for pulling out fine nebulous structures clearly above background. For more information, please see Astrodon's website:
Please note that these three filters together currently retail at just over £1,710 from UK suppliers, €2,180 from European suppliers or $1,690 from US suppliers. Payment is preferred via bank transfer but PayPal is OK with an extra 2.9% to cover PayPal fees. I'll cover postage to you via tracked Courier.
I welcome any questions you may have regarding this listing. Thank you for looking.
Ladies and gentleman,
Thank you for helping me in advance.
As a kid I've always been fascinated with the sky and what was in it. The nights sky is filled with beautiful stars and nebulae and I want to see them for myself and be amazed how insignificant we really are compared to this vast open space. So let me adress some of the key points that I want for a first scope.
1. Around €1000
2. Big aperture, I want to see as much as possible and as far as possible while not losing a clear image
3. I would like to have a push to or go to system
4. Beginner friendly
5. Size is not a problem
8. I prefer reflectors since it seems they give more aperture for the money but if you know a better scope that sees more with less aperture let me know
9. I have a Canon 550D and maybe I could use this for a bit of astrophotography. This is last on the list tho and can be scrapped if the first 3 points aren't met
Of course build quality is very important when making my choice so keep that in mind as well.
I'm looking forward to you guys advice.
Happy stargazing and clear skies!