MRPS The Night Sky Presentation 20210510 - Stan Mansas

MRPS Tech Night

The Night Sky

Presented by: Stan Mansas

Background Image: Stellarium

‘Inspiration'

• Peter Starr, Dubbo Observatory

– "http://www.dubboobservatory.com/”

• Richard Tatti – Nightscape Images

– "https://www.nightscapeimages.com.au/”

• Nico Carver (geeky but excellent)

– "https://www.youtube.com/watch?v=Qb1ceFM-DkQ”

• Trevor Jones (Astrophotographer, Canada)

– "https://astrobackyard.com/astrophotographer"

Peter Starr

Richard Tatti


Carina Nebula, 6000 to 10,000 light years

Introduction


Introduction


Image by: Stan Mansas


Introduction





Keyhole Nebula,, 9,000 light years

Introduction




McNaught Comet Gisborne 2007

35 to 150 million kms from the Earth at its closest approach

Canon 300d, 6.3mp



Before:

Focal: 19mm, f2.8

Exp: 15s

ISO: 800



Before:

Focal: 19mm, f2.8

Exp: 15s

ISO: 800

After:

Orion Constellation

The Horsehead and Flame Nebuale




The Horsehead and Flame Nebulae

1,500 light years Image by: Stan Mansas


Before:

Focal: 19mm, f2.8

Exp: 15s

ISO: 800

After:

Orion Constellation

Orion & Running Man Nebulae




The Orion and Running Man Nebulae

,344 ± 20 light-years

1,344 ± 20 light-years


Before:

Focal: 19mm

f2.8

exp: 15s

ISO 800

After:

The Pleiades or Seven Sisters




The Pleiades or Seven Sisters

444 light years

RAW File

Focal: 200mm, f2.8

Exp: 25s

ISO 800


Yorketown South Australia Sept 2019

Foreground

Background

Single image

Focal: 11mm (18mm)

Aperture. f2.8

Exp: 3 sec

ISO 1600


15 images

Focal: 11mm (18mm)

Aperture. f2.8

Exp: 28 sec

ISO various: 1600, 2500 & 3200


Canon 50d, Tokina 11-20mm f2.8




Final: 15 stacked and 1 blended image


Milky Way

Photographing the Galactic Centre

The Milky Way Core or Galactic Centre


CONTENTS

1. Gain an understanding of the celestial sphere

2. Gain an understanding of Star Trailing

3. Gain an understanding of how to minimise star trails

4. Gain an understanding of the Light Pollution

5. Gain an understanding of how to plan a shoot

6. Gain an understanding of the equipment required

7. Gain an Understanding of Settings, Framing and Focus

8. Practical session


The Celestial Map

Did you know that the night sky has an observable limit of 93 billion light years?

Andrew Z. Colvin - Own work


Image by: Unknown

Diameter of our Galaxy is 100,000 light years


The Celestial Sphere?

How we view the night sky……..

https://en.wikipedia.org/wiki/Celestial_sphere

The Celestial Sphere. (Image Courtesy of the Lunar and Planetary Institute)

Animation by: Rob Knop


Star Trailing

Minimising star trails

1. The 500 Rule, simple

2. The NPF Rule, more complex

Image and Video: Photopills


Camera Settings to minimise Star Trails:

500/400 Rule

CAMERA SETTINGS

The rule of 500 can be used to calculate the exposure time for

your images.

Simply take 500, divided by the focal length of your lens, to get

the number of seconds to expose the shot.

Example: If you’re using a 20mm focal length, take 500, divided

by 20 = 25 seconds per exposure

Full frame: 500/20mm = 25s

Cropped: 500/(crop factor 1.6 X focal) eg. = 15.6s

This method will give you long enough exposure to get good

quality images at night without minimal star trails


Light Pollution & Visibility

During daylight hours our sun washes out the sky masking the stars making them

invisible

At night, although not as bright as the sun the Moon and Light Pollution also limits

our ability to view the stars

Astronomers define light pollution as “artificial light that shines where it is neither

wanted, nor needed”. Making it difficult to in obsere astronomical objects from

polluted locations

Equally as important, obstructions such as cloud cover, smoke and heat haze, all

impact visibility and hinder capturing star images

So what can be done to maximise our viewing capability?


Moon Phases

Images by: https://www.universetoday.com/99591/moon-phases-and-dates/

Image by: https://earthsky.org/moon-phases/2021-moon-phases-calendar-dates-and-times


Moon and Milky Way Calendar

Planning Apps and software:

● Photopills (paid App)

● Stellarium (Free and paid App and PC)

Image by: https://capturetheatlas.com/milky-way-calendars/


Light Pollution

https://darksitefinder.com/maps/world.html#7/-36.383/146.312


The Bortle Scale

Class 1: Excellent dark-sky site

Class 2: Typical truly dark site

Class 3: Rural sky

Class 4: Rural/suburban transition

Fairly obvious light-pollution domes apparent over population

centers


The Bortle Scale

Class 5: Suburban sky

The Milky Way is very weak or invisible near the horizon and

looks rather washed out overhead

Light sources are evident in most if not all directions

Clouds are quite noticeably brighter than the sky itself

Class 6: Bright suburban sky

The Milky Way is apparent only toward the zenith

The sky within 35° of the horizon glows grayish white

Clouds anywhere in the sky appear fairly bright

Class 7: Suburban/urban transition

The entire sky background has a vague, grayish white hue

Strong light sources are evident in all directions

The Milky Way is totally invisible or nearly so

Clouds are brilliantly lit

Class 8 & 9 : City sky/Inner-city sky

The sky glows whitish gray or orange

The entire sky is brightly lit, even at the zenith

Stars making up familiar constellation figures are invisible


The Bortle Scale

How Bortle class affects astrophotography

In terms of backyard astrophotography, the sky quality will

have a huge impact on your images. Deep-sky imaging

under a bright city sky means that you’ll have to put a lot

more exposure time into your projects than someone in a

rural location

You’ll need to work harder to improve the signal-to-noise

ratio of your final image because the signal (light emitted

from the object) is buried underneath a layer of light

pollution

To help capture images with improved contrast and less

background skyglow, light pollution filters that isolate

specific wavelengths of light can be used


The Macedon Ranges Bortle Scale: Class 4 or better

Light Pollution App

Cloud cover App

Apps are readily available

https://darksitefinder.com/maps/world.html#7/-36.383/146.312


When is Milky Way Season?

Southern Hemisphere:

Milky Way season runs from February (very early) to October

January: the Milky Way core is only briefly visible on the eastern horizon just before sunrise.

February and March: out of bed in the early hours to catch those first shots of the season

June and July: the core rises earlier in the evening and presents optimum viewing opportunities

and to capture your photos before bedtime

August and September: the core appears as a large arc in the western sky in the evening,

presenting amazing opportunities for panoramic shots

November: the core is in the western sky after sunset, just above the horizon and is barely visible

and we say goodbye for a few months

Note: Milky Way Photos are best taken when there is no moon or only a quarter moon in the sky.


Ok…… so where do you start?

Create a recipe, your own Night Sky Recipe…….

Step1: The Vision

– This is your vision/ideas of how you would you like to present your image?

Step 2: The Utensils

– What gear/equip you have/need to bring your idea to life?

Step 3: The ingredients

– The elements to bring your idea to life. ie. Timing, location (foreground,

mid ground etc), lighting, props and any other components required to bring

your vision to life?


Ok…… so where do you start?

Step 4: The Method

- The How and What of capturing your image. E.g. single shot, multi

shots, focal length, fstop, ISO, exposure, framing, focus etc

Step 5: The Plating up

- Post processing, artistic flare, single shot, multi shot, blend,

composite etc. output to showcase your image

•


Step 1: The Vision

Vision has to do with seeing, and as photographers we

constantly practice the art of seeing

• Having vision means you know why you’re taking pictures

• What you want to accomplish

• You’re not controlled by what other photographers/trends

• What you’re pursuing and why

Vision starts with inspiration, imagination and being able to visualise your work


Step 2: The Utensils

• Camera: DSLR or Mirrorless camera with manual settings

• Lens: A wide angle lens

– Gathering light is critical! A lens with a fast aperture f2.8

or lower and focal length of 14 to 35 is best.

• A sturdy Tripod

• Spare batteries

• External shutter release/Intervelometer

• Head torch with red light

• Clothing to conditions

• Chair

Other Handy Items

• Lens/hand warmers

• Compass

• Stellarium … App for IOS or Android

(Free)

• Photo Pills for IOS & Android

• GPS … (Very handy to find

locations in the dark)



Step 3: The Ingredients

• Subject, Dark Sky, Moon Phase, ambient light

• What subject location/scene do I want to create

• When is my target going to be visible?

• Subject/Props, foreground, mid, distant

• What type of illumination is available, what will I need?

Image credit: Stan Mansas

Image credit: Stan Mansas

Considerations: Single shot, Multi shot Panorama/Mosaic, Blended images, Composite images etc

Image credit: Eric Hines

Image credit: Unknown



Single shot: Single shot exposure

Stacked: In short, stacking consists of taking different photographs with the same settings, composition,

and focal length, with the ultimate goal of processing them to achieve a particular effect

In Milky Way post-processing, image stacking is generally used to make the stars look brighter while

reducing the noise in the photo. The steps to creating a stack are:

1. Take a series of Milky Way photographs using the same settings

2. Stack the images using software such as “Sequator” for PC (free) Starry Landscape Stacker for Mac

(paid), and once the Stack is made, import the shot into post processing software for editing

Blended: A series of foreground, mid and background images taken from exactly the same spot

blended together

Composite: Foreground, mid and background images taken in different locations and combined together



What subject location/scene do I want to create?

• What foreground, mid, distant object do I want in my image?

• Timing: When will my target be visible within the scene?

• What type of illumination is available? Moon, Urban glow, added ie. light painting etc.

Now we have an idea, subject, place and time. Prepare your set up and start shooting the stars


Step 4: Method

How and what: single shot, multi shots, focal length, fstop, ISO, exposure, framing, focus etc.

Typical Cameras Settings:

• Program Mode - Set to Manual.

• Shoot in RAW

• Autofocus - Turn off, Manual focus.

• White Balance - Manually set white balance

between 3450k – 5000k (3000 cooler 5000

warmer)

• Drive - Set to One Shot.

• ISO - generally will between 1600 to 6400

• Metering - see image

• Exposure Compensation - Set to Zero, no

exposure compensation.

• Shutter Speed - Up to 30 seconds can usually be

dialed in directly. For longer than 30 seconds, set

to Bulb.

• Shutter release: If you don't have a remote

release, you can use the camera's self-timer, 10

sec is best..

• Mirror Lock-Up - recommended

• Stabilisation: Because you'll be using a tripod

turn off all stabilisation

• Turn Image Review OFF


Step 4: Method

Typical Cameras Settings, continued:

• Histogram ON

• Set Optical Resolution to the highest (native) setting.Turn OFF in-camera

long-exposure noise reduction (LENR) if you will shoot separate dark frames.

• Turn On in-camera long-exposure noise reduction (LENR) if you are just

shooting one or two frames.

• Turn off in-camera sharpening if you are shooting JPEGs at a high ISO.

• Set contrast and color saturation to normal if shooting JPEGs.

• Set color space to sRGB. Set to Adobe RGB if you are extremely

knowledgeable about color spaces.

• Turn off flash.

• Put memory card in camera.


Step 4: Method

On location?

Setup your gear, it’s a good idea is to lay down a towel under your tripod it will catch anything you drop

Using apps adjust your setup: Frame your foreground and mid/distant objects so they’re where you want them in

relation to where the subject will be/traverse

Find and Focus: Shooting at night it is very difficult to find targets and get accurate focus. Generally we need to

understand the sky and to find infinity focus to shoot the milky way

How to find the Milky Way:

Having a basic understanding of astronomy certainly helps us with nightscape Photography.

As mentioned earlier, usually some portion of the milky way is visible all year round, we have to understand that the best

images are those that focus on what is known as the Milky Way Core. In the Southern Hemispheres we find the core,

which is the thickest and brightest part of the milky way in the constellations of Scorpio and Sagittarius.

As mentioned there’s amazing software available for desktop and mobiles which for any given day, month and year it will

tell us where everything is located in the day or night sky. Stellarium (free) and Photopills (Paid) are great.


Step 4: Method

Southern Cross

Find: To find the Milky Way Core

find the southern cross draw a line

between Rigil (the first of the

pointers) and Antares the star which

has a yellowish hue, the core is just

below Antares

Antares

Rigil

Galactic centre (Milky Way Core)


Step 4: Method

Focus: Once you find your subject, focusing is probably one of the single most difficult things to

do at night and it takes quite some time to master, and there are 3 methods to try.

Antares

Tonights method: Turn on live view and focus manually on a bright star or the moon. Using zoom

buttons on rear of camera zoom in X10. Rack the focus ring back and forth. When the star

becomes the smallest/a sharp point it’s in focus.

Note: A still camera is critical. Any shake what so ever will affect your image. Ensure that you are

out of the wind, no camera straps and use a remote trigger


Step 4: Method

Focus: Other Methods:

2: Focus the camera on a distant mountain or landscape whilst it’s still daylight and make sure the lens doesn’t move before

you shoot at night. This method does not work with Focus by Wire lenses. (Usually mirrorless lenses)

3: Shine a light or torch on a fence post at an appropriate distance once it’s dark outside (this distance varies depending on

focal length of lens … see Depth of Field Calculator later) and repeat steps explained previously using live view screen.


Step 4: Method

Frame & Take a Test Shot - Check Image & Exposure

Take a test exposure.

Go to image preview

Check for focus, star trailing and exposure

Bring up the Histogram

– Check against the reference chart

– Don’t clip blacks or highlights

– For MW best is neutral or slightly right

– Adjust ISO up or down

Tweak shutter if required, but watch for star trailing

Image by: https://www.lonelyspeck.com/milky-way-exposure-calculator/


Step 5: Plating Up - Processing your Image

Foreground

Background

Single image

Focal: 11mm (18mm)

Aperture. f2.8

Exp: 3 sec

ISO 1600


15 images

Focal: 11mm (18mm)

Aperture. f2.8

Exp: 28 sec

ISO various: 1600, 2500 & 3200




From this

To this

This is a whole new topic and not for today. There are plenty of resources on online Richard Tatti has some free online

tutorials @ https://www.nightscapeimages.com.au/workshops---online.html





Final: 15 stacked and 1 blended image

This is a whole new topic and not for today. There are plenty of resources on online Richard Tatti has some free online

tutorials @ https://www.nightscapeimages.com.au/workshops---online.html


Tonights Practical: #1

Rising Milky Way Core at 2030 10/5/2021

E SE S



E SE S



Focusing in the Dark

Out of Focus

In Focus

Out of Focus


Night Sky Pocket Guides


Clear Skies

Thanks for listening


MRPS The Night Sky Presentation 20210510 - Stan Mansas

Create successful ePaper yourself

Delete template?

Save as template?