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Colours of the Night Sky
The Amateur Digital Astrophotography
Piotr Fita
Warsaw University, Faculty of Physics, The Optics Lab
The Astronomical Club ALMUCANTARAT
Logo designed by Armella Leung, www.armella.fr.to translated by Robert M. Sadowski
This project has been funded with support from the European Commission.This publication reflects the views only of the author, and theCommission cannot be held responsible for any use which may be made of theinformation contained therein
Festiwal Nauki 2005 Barwy nocnego nieba
What Do We Make Photos of the Night Sky for?
• To see more
• To see in colours
• To record the rare events
Festiwal Nauki 2005 Barwy nocnego nieba
What Can We Make the Photos of the Sky with?
With anything we have at hand!
•The digital compact photocamera
•The SLR photocamera (either digital or standard)
•The webcamera
Festiwal Nauki 2005 Barwy nocnego nieba
Digital Compact PhotocameraSpecifications The simplest
modelThe best
modelMaximal exposure time ½ s 10 min
Maximal sensitivity (film speed) ISO 100 ISO 400
Maximal aperture size 4 1,5
Focal length (equivalent to the 36mm picture format)
35 mm 28-200 mm
38-350 mm
PRICE ~ € 125 ~ € 500
Festiwal Nauki 2005 Barwy nocnego nieba
Digital Compact Photocamera
• Photography of the constellations
Applications
Olympus C-5060 WZ
Phot. Piotr FitaThe Astronomical Club Almucantarat
Festiwal Nauki 2005 Barwy nocnego nieba
Digital Compact Photocamera
• Photography of the Moon and planets
Applications
Phot. Piotr FitaThe Astronomical Club Almucantarat
Canon Powershot A20 with telescope of F = 900 mm
Festiwal Nauki 2005 Barwy nocnego nieba
Digital Compact Photocamera
• Photography of the rare events
Applications
Phot. Piotr FitaThe Astronomical Club Almucantarat
Venus in transit across the solar disc, June 8, 2004 r
Canon Powershot A20 with telescope of author’s own design
Festiwal Nauki 2005 Barwy nocnego nieba
Digital Compact Photocamera
• Photography of the big star clusters
Applications
And many other…
Phot. Piotr FitaThe Astronomical Club Almucantarat
The open star cluster Praesepe
Olympus C-5060 WZ
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The SLR Photocamera (either digital or standard)
Maximal exposure time Anyone
Maximal sensitivity (film speed) 1600 ASA
It may have attached lens of any typeor be directly attached to the telescope
PRICES:
Standard SLR camera : € 12-50 film 1600 ASA: € 10
Digital SLR camera: > € 600 ,
But this is the best tool for astrophotography!
Festiwal Nauki 2005 Barwy nocnego nieba
The SLR Photocamera (either digital or standard)
Applicable to photography of all objects, even the nebulae
Phot. Piotr Fita, Andrzej RzepeckiThe Astronomical Club Almucantarat
The nebulae in Orion
Standard SLR camera EXA Ib
The „North America” nebulosity
Digital SLR camera Canon EOS 300D
The Zenit 135 mm telephoto lens
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The WebcameraIn connection with a telescope or photo lens allows
to take pictures of the Sun, the Moon, and the planets
Phot. M. Marszałek, E. Chludziński, A. Dwornik, R. Konieczny, G. Mikołajczyk, A. Rzepecki, M. Tokarski, A. Urbańska, W. Warkocki, R. Zięba,
The Astronomical Club ALMUCANTARAT
Festiwal Nauki 2005 Barwy nocnego nieba
The WebcameraAfter modification allowing for the long exposures it is also
suitable to take pictures of the nebular objects
Phot. M. Marszałek, P. Fita, N. Domińczak A. Majcher, M. Nowakowski, W. Rutkowski, A. Urbańska, R. Zięba
The Astronomical Club Almucantarat
Festiwal Nauki 2005 Barwy nocnego nieba
The Webcamera
Total cost:Camera: ~ € 25
Modification: ~ € 12 (the Philips cameras only)
Adapters: € 10 PLN
Lens: up from € 9
Very economical method!
but
the laptop is recommended!
http://ccd.astronet.pl
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How to Make a Photo of the Sky? Method 1 – the simplest
In the main focus of the fixed camera
Advantages:
•Simplicity
•Saving time
•Minimal efforts and expenses
Shortcomings:
•The blurred star-tracks at the long exposures
•Weak objects may remain unrecorded
Or „just so…”
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How to Make a Photo of the Sky?
Method 1 – the simplest Let’s go:
1. Mount the camera on a tripod
2. Set up manually distance scale to infinity (in the simple digital
cameras use the „landscape” mode)
3. Set up the lowest aperture number, the exposure time for a few or
even for some tens of seconds, and high sensitivity (film speed)
of ISO 200-400
4. In order to avoid vibrations release the shutter by a remote control
cablean electronic pilot, or by a mean of a self-shutter
The results?
Festiwal Nauki 2005 Barwy nocnego nieba
How to Make a Photo of the Sky?
Method 1– the simplest
Disappointed?
The stars are too small?
No colours?
Let’s make the stars blurred!
Phot. Piotr FitaThe Astronomical Club Almucantarat
Olympus C-5060 WZ, focused for the wide range (f = 28 mm) exposure 15 s
Festiwal Nauki 2005 Barwy nocnego nieba
How to make a Photo of the Sky?
Method 1 – the simplest
Cygnus
Lyra
Sagitta
Delphinus Aquila
fot. Piotr FitaKlub Astronomiczny Almukantarat
Olympus C-5060 WZ, focused for the wide range, f = 28 mm, ekspozycja 15 s
Festiwal Nauki 2005 Barwy nocnego nieba
How to Make a Photo of the Sky?
Method 1 – the simplestHow to choose the focal length?
To make pictures of the constellations f = 28-200 mm is sufficient
While
To obtain photos of the Moon, the Sun (with filter only!),
and planets The focal length above is required 500 mm
Hence the reflex (SLR) camera is indispensable!
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How to Make a Photo of the Sky?
Method 2- more difficultWin the so-called afocal projection,
i.e. with camera directly touching the eye-piece lens (of a telescope, psy-glass, binocular…)
Advantages:
•Big magnification with compact camera
•Low expenses
Shortcomings:
•Worse picture quality than in the main focal plane
•Method more complicated than photography in the main focus
Festiwal Nauki 2005 Barwy nocnego nieba
How to Make a Photo of the Sky?
Method 2 - more difficult Let’ go:
1. Set up manually distance scale to infinity (in the simple digital
cameras use the „landscape” mode);
2. Aim the telescope (a spy-glass or binocular on tripod) at the chosen
object;
3. Apply (attach) a camera to telescope’s eye-piece;
4. Focus the image carefully with the telescope’s eye-piece control screw
while observing it at the camera display (or in the viewfinder of the
SLR camera);
5. Release the shutter;
6. The focal length, aperture size, and exposure time have to be found
experimentally. Results?
Festiwal Nauki 2005 Barwy nocnego nieba
How to make a Photo of the Sky?
Method 2 – more difficult
Partial Solar eclipse, May 31, 2003Canon Powershot A20 + spy-glass with magnification 12x
Phot. Piotr FitaThe Astronomical Club Almucantarat
Festiwal Nauki 2005 Barwy nocnego nieba
How to Make a Photo of the Sky?
Method 2 – more difficult
Canon Powershot A20 + telescope of 27 cm diametre and focal length 4.5 m
Phot. Piotr Fita, Agata KarskaThe Astronomical Club Almucantarat
Festiwal Nauki 2005 Barwy nocnego nieba
How to Make a Photo of the Sky?
Method 2 – more difficultHelpful advices:• To attach a camera to any telescope it is useful to buy
(to do it yourself) the special sleeve (F-adapter);
• In compact cameras with zoom lens the longest focal lengths (tele) should be set up;
• The camera’s lens has to touch the eye-piece of a telescope.
Festiwal Nauki 2005 Barwy nocnego nieba
With, or Without Tracking?
Taking pictures of the weak objects requires tracking the camera along the diurnal movement of the sky
fot. Piotr FitaKlub Astronomiczny Almukantarat
Exposure time 13 min Exposure time 15 s
The Earth’s rotation
Apparent diurnal movement of the celestial sphere
The blurred traces of stars on the pictures with long exposure time
Only bright objects cab be seen on the pictures
with short exposure time
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With or Without Tracking?
Without tracking With tracking
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With or Without Tracking?
The mount with tracking can be:
• Done by yourselfVademecum of the Amateur Astronomer,
Internet – the „barn door” type mount
• PurchasedMeade, Celestron, Orion, Uniwersał
Festiwal Nauki 2005 Barwy nocnego nieba
With or Without Tracking?
Drive
Hand Electric
Mechanic(Orion, Uniwersał)
Digital(Meade, Celestron)
For the astrophotography purposes the mount has to be equatorial (paralactic), and not azimuthal!
Festiwal Nauki 2005 Barwy nocnego nieba
The Computer Picture Processing
The computer picture processing makes up to 70% of the digital astrophotography!
Festiwal Nauki 2005 Barwy nocnego nieba
The Computer Picture Processing
Golden rule of the digital astrophotography:
Take as many as possible identical photos and add them all together
20 photos by 15 secs each
=
one photo exposed by 5 minuts!
Festiwal Nauki 2005 Barwy nocnego nieba
The Computer Picture Processing
Golden rule of the digital astrophotography:
Take as many as possible identical photos and add them all together
Advantages:
• Noise reduction• Increasing sensitivity• Pictures with long effective exposure time with no
tracking!
IRIS
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Visualization
Adding
Superposing
× 23
Phot. Piotr Fita, Andrzej RzepeckiThe Astronomical Club Almucantarat
Festiwal Nauki 2005 Barwy nocnego nieba
Visualization• Blurring the star images
• Removing the background
• Lowering the contrast
• Sharpening the pictures of the Moon and planets
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CorrectionRemoving the dark frame
=
-
dark framesingle exposure
Phot. Piotr FitaThe Astronomical Club Almucantarat
Festiwal Nauki 2005 Barwy nocnego nieba
CorrectionRemoving the dark frame
Galaxies M81 and M82
Webcamera with F = 50 mm lensPhot. Piotr FitaThe Astronomical Club Almucantarat
Festiwal Nauki 2005 Barwy nocnego nieba
CorrectionThe blurred pictures
The Little Dipper (Ursa Minor)
The standard SLR camera with F = 135 mm lens Phot. Piotr FitaThe Astronomical Club Almucantarat
Richardson – Lucy’s algorithm
Festiwal Nauki 2005 Barwy nocnego nieba
CorrectionRemoving the regular structures
M31 Galaxy
The webcamera with F = 135 mm lens, photo made in the B band Phot. Piotr FitaThe Astronomical Club Almucantarat
Filtering with help of the Fourier transform
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How To Do It?
SuperposingAdding
VisualizationCorrection
and many other options…
The IRIS programhttp://www.astrosurf.org/buil/us/iris/iris.htm
IRIS is freeware!
Festiwal Nauki 2005 Barwy nocnego nieba
Other programs
• Astrostack
http://www.astrostack.com/
• TeleAuto
http://www.teleauto.org/indexEn.php
Festiwal Nauki 2005 Barwy nocnego nieba
Knowledge
• A webpage dedicated for the digital astrophotography:http://ccd.astronet.pl
• „The CCD Observatory at School”(incl. A practical manual of IRIS program)http://www.cft.edu.pl/~tomsow/ccd/ccd_pl.pdf
• Homepage of the EU-HOU Projecthttp://www.cft.edu.pl/astro/
Festiwal Nauki 2005 Barwy nocnego nieba
Shopping
• Delta Optical
http://www.deltaoptical.com.pl
• Astrokrak
http://www.astrokrak.pl
• Uniwersał
http://www.universe.com.pl
• Website i-sales Allegro
http://www.allegro.pl
Festiwal Nauki 2005 Barwy nocnego nieba
You can take nice photos of the sky almost with any camera!
Good Luck!