ASTRONOMY, ASTROPHOTOGRAPHY & YOU

By Haseeb Modi

ASTRONOMY, ASTROPHOTOGRAPHY & YOU:

Astrophotography is extremely popular even for those visually interested in astronomy. However,  to own a complete unit comprising of even minimal equipment which helps track the skies for long durations of time can quickly become expensive and then some.

Amateur astronomers of all ages like to indulge in astrophotography. There are die hard viewers who only prefer visual viewing and that’s fine.  There are also those who prefer the simple classic way of observing with either an Alt / Az or Dobsonian mounts by manually slewing to objects. This involves a relatively good understanding of the skies and keeping star charts or smart apps on your Android phone to chart out the sky map for your location on the given date and time. 

I bet almost everyone right from their school days wanted to see the Planets. Imagine if we are able to capture a distant deep sky objects many light years away onto our PC screens or any screen for that matter?  Moon is taken for granted but how many would have looked deep enough to see its numerous craters?

As with any hobby, there are certain considerations ( not caveats ) and astronomy has many of them. For eg:-

·         Cost

·         Weight constraints

·         Portability ( would naturally involve weight )

·         Volume ( you need to store your gear some place )

·         Usability ( depends on where you live and your work pattern )

·         Performance ( all parts in working condition for years )

·         Light pollution

·         Manual operation with ease

·         Both Manual and Automatic or go-to

·         Precision tracking

·         Alignment procedures

·         Polar alignment for astrophotography

·         All star alignment for visual with go-to

and many, many more. Fortunately, all above considerations are something  amateur astronomers would relish.  Accessible to them are equipment suitable for their needs. This is where the fun starts.

You live in a big city, light pollution, work pattern and a newcomer to this hobby,  the answer would suggest a Mount and Scope which allows tracking of objects automatically so that you spend more time viewing and less time star hopping or trying to find objects manually.

There are a huge variety of Mounts designed for automatic alignment and tracking in both Alt / Az and Equatorial formats.  Only a few user inputs are needed and your journey to catch each of the 110 Messier objects starts. Mind you, there are thousands of other objects that will keep you mesmerized for a lifetime.

Having had the taste of some of our Celestial neighbours,  especially Saturn  or Jupiter, even Lunar, the immediate thought that crosses our minds is to snap a picture and show off to our family and friends. Easier said than done.  That is not all. You then start catching what is known as in astronomy circles, “Aperture fever”.

Costs, portability, weight aside, ( even your health and age takes a backseat once you get aperture fever ), you yearn for that extra inch of space. To probe deeper, to see more details that may have once amazed you, to now stun the daylights out of you.  By this time, you have earned yourself a nice little niche in the list of amateur astronomers and gained relatively good experience exploring the heavens. Time to move on.

Choices aplenty the shopping cart or your neighbourhood telescope store suddenly becomes a very busy place.  For those married folks, the wife may also take a backseat for awhile but its all in good fun and good investment. At least that is what we try to tell our spouses.  We even allow for a bit more spending on their part, at least that’s what our wife’s tell us, in good fun of course.

Whereas the first yearning was for any scope and mount, you suddenly find yourself having a good stock of eyepieces, accessories, finderscopes and a couple of telescopes and mounts in the space of a very short time.  New designs that hit the market ever so often only make matters bett....err worse. But buy one must.

To me, buying any astronomical item that serves the purpose is better than spending on items that you most likely never use. On the good side, most of the astronomical gear have a very good re-sale value, even after years of use.

Having satiated your appetite with aperture, your next line of thinking is somewhere between becoming an amateur astrophotographer or a casual one. Almost everyone has a camera and for those who don’t, the Android phones have one.  All it takes is one look at Saturn and then trying to align your camera towards the eyepiece, focus and shoot. A blurred, out of focus or clear, stunning image may appear with which you show your family and friends and proudly share on social networking sites.  A lot of ‘likes’ and ‘wows’ later, you suddenly become serious.

Note:  The technology available today was not available perhaps ten years back and Astronomy is considered the second most popular profession. Therefore it is fair to assume most of the amateur astronomers are ‘visual viewers’ and not astrophotographers and continue to be so even to this day.  There is a certain charm in star hopping or viewing an object for hours on end. Come back the next night and view the same object and you may see more details emerge. You train your eyes and observing skills as you experience the skies.

Astrophotography can be rewarding and how much you spend in terms of both money and time, would depend entirely on your own self analysis of what you wish to achieve.

Again with today’s advancement in technology, a plethora of options are available for beginners, intermediates who intend to embark on this very fulfilling journey in astro imaging. I have not mentioned the word ‘professional’ as this category of imagers would most likely have their own blogs or websites and would have written books on astrophotography. I know a few who actively share their spectacular images on various websites and my hats off to them.

While many are satisfied by simply using their point and shoot cameras or android phones to snap a image or two of brighter objects like our Moon or Saturn, quite a few go a step further and try their hand in longer exposures, i.e., anywhere from 15 secs to 24 hours.  Okay now 24 hours may sound a bit too much but it has been done over a span of several nights. Auto guiding, specialized guiding software like PHD etc., help keep a scope and camera pointed at the selected object while dedicated software like Backyard EOS for example lets you compute the duration and number of exposures you intend to take.  All this means you can set everything up and go back to watch TV or stay up and use your other scope for visual viewing.

Which category one intends to fall into is something only the user can resolve.   This could be through trial and error or if fortunate enough, suggestion and use of your friends imaging gear. The latter is wishful thinking though.  But today’s technology offers us so many good choices, it is rather difficult to make a serious error. The most sought after design for Astrophotography is the “Equatorial Mount” and there are plenty to choose from. Both from heavy to medium to lightweight.

Then there are Alt / Az mounts which allow the user to take up to 30 seconds without stars trailing or perhaps even more by installing a ‘wedge’.

Then you have an altogether a completely new concept developed which lets you mount your camera and image the night skies.  This small and lightweight instrument is made by various brands but the one I own is iOptron’s Skytracker. ( You can read various reviews on the web as well as on www.indianastronomer.net )   

There are portable versions of Equatorial mounts such as iOptron’s SmartEQ and even the ZEQ25GT.  You want to go up a tier then perhaps the iEQ30 or iEQ45. But for beginning and intermediate needs, the ZEQ25GT should prove adequate.

There are plenty other options as well but I am listing what I have seen and from my own experience.

The other important aspect to astrophotography is the choice of scope. Nothing less than  a Pandora’s box this.  On one hand you want to both view and image, on the other, you want the best imaging scope.  There are in-betweens fortunately so choose wisely.  Only be careful on the focal length and design.  A longer focal length may give you very good views on the Planets and other brighter objects but will induce star streaks whilst imaging deep space objects.  A short focal length and fast focal ratio would mean faster exposure times and wide field images of deep sky objects.   A large aperture scope would mean tons of light gathering prowess which would equate to much pleasing details but at the cost of volume and weight.  Lots of considerations.

Many astrophotographers settle on a nice little Doublet or ED or a Triplet, simply because these Refractors do not require much cool down times or collimation as well as being portable. Their lightweight makes them easier to mount on Mounts which have stipulated payloads so that a guide scope can be added atop or in future as you learn the art.

Some settle with an Achromat refractor as long as they do not mind the purple fringing or halos around the stars and brighter objects. As I said earlier, the answer lies with the user.

Some live with the Schmidt-Cassegrain design as this allows for better visuals and detailed images of the Planets.  However their long focal length and focal ratio would mean you need to use a ‘Focal Reducer’.  The Focal reducer acts in reducing the Focal ratio of an F/10 to an F/6.3, thus enabling  faster exposure times.

Finally you have to decide on the type of Camera you wish to image with. A DSLR is quite versatile and there are dedicated astro imagers too.  For DSLR owners, modding can be performed at a cost or through dedicated filters. One filter which really works well in light polluted cities is the CLS II clip-in filter. 

Processing software and free at that like Deep sky stacker, Registax, AutoStakkert, Gimp2 are available for the user to download and use. It helps if after spending all that money on astronomical equipment, to get yourself a dedicated astro processing software.  There are many available, even for those who are not technically savvy at processing.  These are programs that compute tons of information by the mere click of a few icons.

Personally I find the Deep sky stacker and AutoStakkert to be of great value in helping stacking images, while Photoshop Elements and PaintshopPro together with Noel Carboni’s tools provide enough processing power to bring out details in my images. I consider myself at the very least, a beginner when it comes to astrophotography but I pride myself in the knowledge that I have captured loads of images which my family and friends like. 

More importantly, I know my limits and therein lies the answer. The equipment which I own perhaps justify these limits and my work pattern, location, cost and other considerations.

Today the modern astronomer has the technology at their disposal to start almost instantly. The options are on par with the considerations.  All you need to do is choose wisely.  This is one hobby where the equipment lasts for a lifetime but the time available in our hand to look up each and every object in the sky may well take over a lifetime.

Haseeb Modi.

Please visit www.indianastronomer.net to help spread astronomy in India.