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Home , Astrophotography

Let’s Define ‘BEST’

Camera should be relatively easy to use, almost obvious & familiar

Camera should be versatile and able to do it all, providing opportunities to explore all types of astro-…& more

Software to control camera and process images should be relatively inexpensive and, where possible, multi-platform compatible: Windows & Mac

Canon EOS Digital Single Lens Reflex Camera

Full Frame (36 x 24 mm) & APS-C (22.5 x 15mm)

Full frame great for wide-angle, expansive images ( & meteor showers)

APS-C less sensitive to optical aberrations at edge of field; less than ‘perfect’ optics will yield great images

APS-C size is smaller and more optimal for common amateur optical systems

APS-C cost less than full frame

Crop 640x480 video mode or equivalent

Takes 640x480 pixel center of image chip and treats as full-resolution video/

Great for high-resolution lunar, solar and planetary imaging

EOS Utility

Powerful camera control software - Windows and Mac

My Cameras

2004 to 2013 Canon EOS 20D/20Da

Canon EOS 6D Canon EOS 60Da Full Frame APS-C 5472 x 3648 (20 Mpixel) 5184 x 3456 (17.9 Mpixel) 6.54 µm 4.3 µm Nyquist optimum = f/24 Nyquist optimum = f/16 ISO 100 - 25,600 ISO 100 - 6,400 JPEG (8-bit) & CR2 (14-bit) JPEG (8-bit) & CR2 (14-bit)

Crop 640 x 480 video mode Extended IR filter for enhanced H-α

Wide-angle imaging only All other imaging

Timer Remote Controller

Single shot remote release - prevents camera vibration and image blurring

Full camera control programmer () controls time between exposures, length and number of exposures - without a computer

Self-timer to delay sequence after activation

Exposures saved onto camera storage card

Cost < $100

For 7 years used as only means to control camera for all deep-sky imaging - no computer in field

Still using it after 14 years

Does not control video mode

Highly recommended

Image Processing Software

Adobe Photoshop (expensive), Ver. 2.5, 3.0, 4.0, 5.5, CS, CS2, CS6 (OK, I’m addicted)

MUST BE ABLE TO PROCESS 16-BIT IMAGES

Single Shot / Image

Non-trailed images

Mount camera with wide-angle lens on

6D, EF 17-40mm f/4L set at 17mm, ISO 3200, 15 sec

Star Trails

Intervalometer, 60 1-min exposures, ISO 800, blended in Photoshop

Deep-Sky (Stage 1)

Wide-angle, long exposure (1-2 mins) - No star trails

Requires polar-aligned, motorized star tracker - Several commercially available

iOptron SkyTracker system

Tracker, polar alignment scope, ball head & tripod

4 AA batteries or 9V DC AC adapter

Smartphone app available to show where to put Polaris on alignment scope reticle

7.7 lb capacity - ($450)

Very portable

Image Stacking Program

Windows only Cost = $0.00 (Free)

S/N = SQRT(Number of Exposures Stacked)

Canon 60Da, EF 17-40mm f/4L set at 17mm, ISO 3200, 30 1-minute exposures

Meteor Showers

Deep-Sky (Stage 2)

Long exposure (1-2 min), medium (100 - 500 mm) - No star trails

Requires quality, motor-driven, polar-aligned - not auto-guided

Mount should have maximum carrying capacity double the heaviest optical system planned

Perfect optics on a garbage mount will give garbage images

Vixen GP/DX (on wheels) & Paramount MX (semi-permanent)

Good polar alignment will yield sharp star images with 1-2 min exposures without auto-guiding

30 1-minute exposures ISO 3200 DSS Photoshop

Supernova

Asteroids

Comets

Comet Johnson C/2015 V2 - May 25, 2017

DeepSkyStacker Nebulosity

Nebulosity - Stark Labs

Camera control, stack exposures, process images & more

Windows & Mac - $95

Deep-Sky (Stage 3)

Long exposure (1-2 min), long focal length (500 & higher mm)

Requires quality, motor-driven, polar-aligned equatorial mount with auto-guiding

Guidescope or off-axis guider and guide camera

Guider control software compatible with mount & its control software

Must learn how to make all this work together

I have not achieved this yet and have no experiences to report

Canon EOS DSLRs should work just fine

Full Disk Lunar & Solar

800 to 1500 mm FL (depending on full frame or APS-C), very fast speeds

Takahashi Sky 90 + TV 2x PM 60Da Celestron C5+ (1250 mm f/10) 20Da (1000 mm f/11.2) ISO 250 1/2000 sec ISO 800 1/1250 sec

Partial

Takahashi Sky 90 + TV 2x PM (1000 mm f/11.2), 60Da ISO 250, 1/2000 sec, 10-min interval, Canon EOS Utility

Lunar Eclipse

Stellarvue SV115 (800 mm f/7), 60Da ISO unk, 1/2000 to 2 sec, 5-min interval, Canon EOS Utility

High-Resolution Lunar, Planetary & Solar

“” - Jerry Lodriguss

Take a ‘bizillion’ images, stack the best few thousand to obtain great final image

Video allows capture of thousands of sub-images in just minutes

Stacking & powerful Wavelet processing

Windows only, Cost $0.00 (Free)

Stacking only

Windows only, Cost $0.00 (Free)

Stack in AutoStakkert, Wavelet process in Registax

Canon 60Da in Crop 640 x 480 video mode, 8-bit MOV format video

Camera control using EOS Utility

First issue: RegiStax & AutoStakkert cannot read MOV format video

Must convert MOV video to AVI video

Second issue: Several AVI video codices; Windows cannot read all of them

Solution: VirtualDub

Windows - Cost $0.00 (Free)

5-minute video, 60 fps (18,000 frames), adjust image intensity with ISO

Convert MOV to AVI, correct AVI in VirtualDub

Open AVI in AutoStakkert, stack 1000-6000 frames, wavelet process in RegiStax

Example -

Celestron C6 SCT, 150 mm dia, 1,500 mm FL, 1.6x ScopeTronix amplifier, Canon 60Da

2,400 mm FL, f/16 equivalent

Single frame Stack of 1500 Wavelet Process

August 6, 2018 - Celestron EdgeHD 9.25 + 1.6x ScopeTronix amplifier 3759mm FL, f/16

DSLR Shortcomings

1) The imaging chip is not cooled, limiting the maximum exposure length. During exposures, chip warms up and increases thermal noise. I have never seen DSLR image utilizing exposures greater than 5 minutes. Stacking multiple exposures is critical to achieve good signal to noise and image intensity.

2) DSLRs are one-shot- (OSC) cameras with a Bayer filter covering the chip. Algorithms are used to ‘estimate’ the actual color in each pixel, resulting in a slight reduction in resolution. Light intensity hitting each pixel is about 1/3 that for a monochrome chip, so stacking multiple images required.

3) OSC cameras are not ‘good’ for solar H-α imaging. Bayer filter blocks large amount of light and significantly decrease resolution. Detail on solar disk is ‘muddled’. Monochrome camera would be better choice for solar H-α imaging.

4) Video mode limited to 60 fps as slowest frame rate; can be faster. For dim objects like Saturn, acceptable image intensity can only be achieved be increasing ISO, resulting in noisier sub-frames, so… stacking multiple images required.

November 7, 2018