astrophotography 101 · astrophotography 101 1. telescope – your choice remember – the shorter...

Astrophotography 101 The 10 “Beyond the Basics” of Astrophotography

Astrophotography 101 The 10 “Beyond the Basics” of Astrophotography

1. Telescope

2. Equatorial Mount vs. Alt-azimuth mount

3. Camera

4. Necessary Accessories

5. Autoguiding – PHD

6. Focus Focus Focus!

7. Capture and Processing Software

8 Lights, Darks, Flats and Bias Frames – How Many?

9. Pre processing – combining the images

10. Voila – your first image – see what ya got!

Astrophotography 101

1. Telescope – Your Choice REMEMBER – the SHORTER the focal length –

the WIDER the field of view!

Any scope will work for astrophotography!

Decide what you want to photograph – if you

are looking to photograph nebula – a shorter

focal length scope will work – if you want to

get galaxies – longer focal length will be

needed.


Short focal length

scope 530mm Long focal length

scope 1000mm


Short focal length

scope 530mm

Long focal length

scope 1000mm

Astrophotography 101 Excellent FREEWARE program for determining

field of view for your scope AND Camera is :


2. Equatorial or Alt-azimuth Mount?


2. Equatorial or Alt-azimuth Mount? both will work for astrophotography but the Alt-

azimuth mount will only be able to take exposures

for a shorter period of time due to “Field rotation”

An alt-azimuth mount can be placed on an

“equatorial wedge” to achieve the same results


2. Equatorial or Alt-azimuth Mount? Make sure your mount has an “Autoguider” Port –

this is essential for long exposures.


Powering the mount? Make Sure you have a reliable power source for

long time use – generally a good commercial grade

truck or auto battery is enough

NOTE: AMP HOURS - the higher the amp hours the

longer lasting charge available . Minimum 105 ha

Automotive or deep cycle???


Powering the mount? deep cycle batteries can be run down to nothing

and can be recharged – unlike automotive

batteries

Not recommended if you are running dew heaters –

most dew heaters i.e. Kendrick have built in shutoff if

voltage goes too low – need inverter to boost the

voltage….

Deep cycle – avg. 12.89 v max

Auto – 13.8v max


3. Camera Choice DSLR?...CCD?....COLOUR?....Monochrome???

Let’s start with the good ‘ol DSLR!

Easy to use and COLOUR!

Very “software” friendly – lots of astro software works

well with the Canon products. Lightweight and rugged

Shutter can be operated by computer

Easily adapted to most scopes


3. Camera Accessories needed

+ + =

Either 1 ¼” or

2” will work


4. Necessary Accessories Good Planetartium Software Freeware – Stellarium

- Cartes Du Ciel

Purchase - The SKY

- Earth Centered Universe

- Starry Night

Note: ALL of the above software have the ability to operate your telescope mount!!!!!

Astrophotography 101 4. Necessary Accessories Dew Control

Minimum 2 heaters

Objective and

autoguider

Astrophotography 101 4. Camera Control Software Freeware – DSLR Control

APT by Digital Software * minimal charge

Astrophotography 101 4. Camera Control Software Purchase – Images PLUS **

Astrophotography 101 4. Camera Control Software Purchase – Maxim DL

Astrophotography 101 5. Autoguiding - Autoguiders Starshoot – Orion

QHY5 – KW Telescope

Astrophotography 101 5. Autoguiding - PHD Freeware - PHD – the STANDARD in auto guiding!

Astrophotography 101 ASCOM Platform

Astrophotography 101 6. Focus Focus Focus!!!

Bahtinov Mask

Liveview – Canon cameras

Fotosharp – KW Telescope


Freeware –

Focus Max

Astrophotography 101 6. Focus Focus Focus!!!

Images PLUS focus

The LOWER the

Number the crisper

the focus!


7. Image Capture & Processing Image capture and processing software

Freeware - Nebulosity

- Deep Sky Stacker

- Registax

Purchase - Images PLUS *

- Maxim DL

- Photoshop * • - Carboni’s Actions

• - Annies Actions


Carboni and Annie’s Actions


8. Lights, Darks, Flats & Bias – The

Meat and Potatoes!

Remember you don’t need to know how these go

together…just how to produce them! ( Too Geeky

even for me!)


Lights – The Actual Picture! Always take them in RAW format

Take as many as practically possible

Always use same ISO & Exposure for an object i.e. if you use ISO 800 and 480 seconds – do that for the entire sequence

The more you take, the greater amount of information you will get

…but don’t be disappointed…you wont see much!


Raw image 480 seconds….bleckh!


Same image processed!


Darks – The Noise remover! Take at least 50% number of Darks as Lights

Same ISO & Exposure time as Lights

Try to take them at the same temperature as

your Lights – this is important…

Take them with the Objective “Covered”

What do they look like?...


“Hot Pixels”


Processing software uses the Dark frames to

“subtract” the noise from your images to

produce cleaner images that are virtually noise

free.

They are very important – like windshield wipers

that remove raindrops from your windshield.

If you take 30 Light frames – take at least 15 Dark

frames.


Bias Frames – Haven’t a clue what these do

but they are an integral part of the process!

Take same amount of Bias frames as light frames

Usually taken at the fastest shutter speed your

camera will allow i.e. 1/4000 sec.

Taken with the objective covered.


Flat Frames – The Dust Bunny

Removers! Taken at a shutter speed of between 1/5 and 1/30

of a second – you will have to experiment to see

what is good for you

Taken with an “Even” light shining on the objective

using a “light box” that can be easily made or

commercially purchased

Astrophotography 101 Home made light

box

Commercial light box


Dirt and dust


Flat Frames – The Dust Bunny

Removers! Image processing software “removes” these nasties

from your images!

Take same number of Flat frames as light frames


Summary of Frames to Take: Light Frames – the more the merrier

Dark Frames – Objective Covered – same ISO/Exposure

Bias Frames – Objective Covered – fastest exposure on

camera and same ISO

Flat Frames – 1/5-1/15 sec. evenly illuminated light over

objective same ISO

***DO NOT MOVE CAMERA POSITION! FOR ANY OF THESE

FRAMES!*** this is critical!


9. Pre-Processing -Combining the

Images Now the FUN Starts!

Image processing software will take “ALL” your frames.

Align them, tweak them, stack them into ONE RAW IMAGE!

Again, don’t be disappointed with what you get –

remember it is only the RAW image…there is a TON of

information in that one bleak looking frame!...remember…

Astrophotography 101 30 frames @ 480 seconds = 3 hours of raw data!....Awesome!

Can you guess what the image is????


10. VOILA! Let’s see what we got!


Click on

“Color “Tab

This panel will

show up


To bring out

detail use the

“Break Point”

Slider


Save as an

uncompressed

TIFF file

Set “slider”

to 2500


…And Now for the LIVE demo!!!!!!!

astrophotography 101 · astrophotography 101 1. telescope – your choice remember – the shorter...

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