Monday, November 20, 2017

What do you need for astrophotography?

What do you actually need for deep sky astrophotography?



Deep sky astrophotography is an enjoyable yet challenging hobby. It not only results in amazing images of space to share with others, but the process can be very rewarding in itself.

The feeling of excitement that occurs when a color preview appears of a nebula on your camera display is like nothing else. This is the type of moment a night sky photographer remembers for the rest of his/her life.

What do you need?



Beginners may run into a few road blocks that can hinder their progress. It can be daunting to look for just the right astrophotography telescope and camera when so many options exist. 
Let's clear the air and talk about what you actually need for basic deep sky astrophotography:

Essential gear needed to participate in astrophotography:

The Basics


Imaging telescope
DSLR camera
T-Ring and Adapter
Remote shutter release cable


Extras



Filters
Field Flattener/Reducer
Guide Scope
Guide Camera
Imaging software and computer


A great place to start is the tracking mount. You'll need a solid platform to carrying the telescope and photography gear through an imaging session.



An equatorial mount that has been properly polar aligned will compensate for the Earth's rotation. This way, long exposure images of 1 minute or more will contain crisp stars with no trailing.

The deep sky target of choice, whether that's a nebula, star cluster or even a galaxy - will start to appear once an adequate amount of light has been collected on the camera's sensor.
Astrophotographers then "stack" many images together to improve the signal to noise ratio.  By combining many long exposure images, it is possible to create impressive astrophotos.  The goal is to create images that are smooth, colorful and sharp.

There are many software applications available for image processing an astrophotography image. Adobe Photoshop is a popular choice due to its wide use by photographers and familiar tools.


No matter which road you decide to take, just take action.  Don't get held up in the decision making process and continue to sit on the sidelines while others move forward. Make progress one step at a time, and learn the ropes along the way. 

If you are truly dedicated to capture your own breathtaking astrophotography images, you will overcome all obstacles along the way.

Resources

Related Article: Beginner DSLR astrophotography 

Astrophotography Portfolios (Celestial Pixels)

Purchase Astrophotography Gear Online (Ontario Telescope and Accessories)

 

Saturday, November 18, 2017

Apochromatic Refractors for Astrophotography

A beginner telescope doesn't have to break the bank. A small dobsonian telescope such as the Orion SkyQuest XT4.5 provides incredible views at an affordable price.  But what if you want to start taking pictures of the faint deep sky objects in the eyepiece?

When it comes to astrophotography, an Apochromatic Refractor Telescope is hard to beat.

The Soul Nebula using an Apochromatic Refractor Telescope

Above: The Soul Nebula photographed using a 70mm Apochromatic Refractor

The world of astrophotography


Make no mistake, deep sky astrophotography is not for the faint of heart. It will push your patience and your wallet to the limit. The act of taking long exposure images with a camera and telescope requires a tracking equatorial mount to compensate for the rotation of the Earth.

Many additional tools and software are needed to produce quality deep sky images on a regular basis. With that begin said, choosing the right telescope for astrophotography is a great place to start.


The optical layout of a refractor telescope
Optical layout of a typical refractor (Starizona)

Apochromatic Refractors for Astrophotography

Refractor telescopes gather light by using an objective lens at the front.  The apochromatic design corrects three wavelengths of light, and produce better images than an Achromat can. A apochromatic refractor with a doublet or triplet design eliminate false color. 


An apochromatic refractor telescope such as the William Optics Zenithstar 61 is an excellent choice for astrophotography. The lens design of an apochromatic refractor telescope results in images with superb color correction, and no chromatic aberration.


Above: The William Optics Z61 is an afforable Doublet APO refractor telescope

They are also much more portable and easier to use than a heavy Newtonian or Schmidt Cassegrain Telescope.  With accurate focus, these telescopes can produce images with razor sharp, tiny stars.

The video below showcase the beautiful Meade Series 6000 APO refractors in various sizes.  The larger the objective lens, the more light gathering power the telescope has.  Apochromatic refractors increase in price quickly as they get larger.
 


Although the apochromatic design is more expensive, it is well worth it for astrophotographers that want to capture the best image possible.  Invest in a quality telescope from the beginning, and reaps the rewards for a lifetime.

Related Articles


APO Refractor Review: Explore Scientific ED127 ED (SkyNews)

Doublet vs. Triplet Discussion (Cloudy Nights)




The Triangulum Galaxy - Photographed using an Explore Scientific ED80 APO Refractor