Let’s talk Astro Photography
Well hey . . It’s 2019, glad to be here and glad to talk about a subject that is as confusing as . . .
well the number of countless sights and other objects to see and photograph in the night sky.
I am really amazed at what I can photograph using a telescope, a monochrome astro camera and an GEM mount ( there are terms I will use that I recommend you google if you do not understand them, reason is I want to get to the meat of the idea and not muddy it up with techno babble) . . . but really it was not very long ago that what I can achieve was only in the realm of observatories, very rich amateur astronomers or specially funded programs at universities . . . But thanks to economics and advances in digital cameras, telescope optics and computers that has all changed. Now the average amateur astronomer can take outstanding photos without having to mortgage ones home. Yes it can be done with modest equipment at a modest price-tag. I am a scrounge and will hunt out bargains on used gear before I will spring for new gear. The items listed are not the de facto gear, but just what I have personal knowledge of. Ask any amateur astro photographer and you’ll get a completely different list of gear. This is just what works for me after hours of use and trial and error, reading, researching and sometimes just taking a chance.
I really wish I could have found a website that could have guided me to what I know now. I being me would have done it the hard way, but, that is not the point of this post. I will show you one way to do this . . . My focus was DSO’s (Deep Space Objects) like nebula, galaxies star clusters and occasionally the moon or the sun. Like many I rushed into it without a lot of research. Yes I had access to the internet, but I didn’t know the right questions. So I bought before I read . . . Well after a few years of fine tuning . . . I now have a clear idea of how to do what I want to do.
Step one . . . Identify what interests you . . . visual or Astro Photography (AP) or both, and maybe you want to do Deep space objects, planets, solar . . . those are just 3 of the many areas of interest. I will outline a rig for doing wide field astro photography of DSO’s. I will show you what I use for this but realize the equipment brands are not important, the equipment type is.
I chose to use the following
- CGEM mount (Computer controlled German Equatorial Mount) (used)
- 60mm ED scope (used)
- Monochrome Astro camera with electronic filter wheel and Narrow band filters (new)
- automated camera / mount control (new)
- specific software (some free / some at cost)
- capable tablet PC or smartphone (may already have or need new-used)
- Laptop with software to process images (may already own or need)
I bought almost everything used. My fave website is CloudyNights.com which is an astro website that has a lot to offer the newbie, beware it can confuse the newbie as well . . . it also has a great buy/sell section. Wait a moment, HANG onto those happy dollars right now . . . just slow down and breath . . . ok that’s it, now that we’re back in control. I am hoping to save YOU the angst I had when I decided to “Hey I wanna make some pretty images of that purdy nebula” and went on a buying spree . . . yep! I’m not perfect! . . . you heard it here . . .
So after some trial and error I found that in order to make photos of “purdy” nebula I needed the right equipment. My dSLR which could fill in occasionally just couldn’t cope with the light pollution where I lived, (a side not: A Color astro camera works much like a dSLR and has trouble with light pollution as well) . . . well I found out I needed narrow band filters to cut through the light pollution and also reveal the light that was emanating from the nebulae I wanted to photograph (the ol’ Mark I eyeballs just can’t see em mostly because they’re so dim and in a wavelength that my receptors can’t see) . . . yes there are filters for dSLR’s but then you need to modify your dSLR camera and that isn’t going to happen. I digress sorry. So I chose a monochrome camera which requires you use special filters with, in order to take a color image I need to shoot 3 photos in Red, Green, Blue (LRGB) or I can also shoot using Ha, Oiii, Sii narrow band filters as well as a Luminance filter. I needed a filter wheel for the camera as well. I know this is sounding complex but bare with me a bit more.
I next whittled down the range of telescopes to something between 50mm and 80mm to fit the FOV of the scope and camera combination to the objects of interest. YEP sometimes bigger isn’t always better. My scope of choice is AT60ed or AT72ed and ZWO asi1600mm-pro camera which has a 4/3rd’s sensor size. If I need more coverage I can use a standard manual camera lens in place of the telescope (there are some caveats that come with using a camera lens instead of a telescope).
So far we have a camera, filter wheel and filters(bought new) and a 60mm telescope (bought used)
Now let’s talk mounts, much like the story of Goldie Locks we need one that is just right . . . again I chose an Equatorial mount versus an AZ-EL Mount, both have advantages and disadvantages. I chose EQ mount because of the way it works. I bought a used one. (I will say this get the one with the biggest payload capability as the photo equipment and scope quickly add up in weight, So a 40lb payload is a small payload, you will want more. Pay once for a good mount with a medium payload of at least 60lbs, you’ll be happy you did. For this example I bought a used Celestron AVX mount, it’s a bit on the light side but it works well for a light payload (30lbs or less). It’s not a good idea to skimp on the mount.
Now we’ve added a CGEM mount (bought used)
A new item was the addition of a small computerized automation computer (under $200 bucks) that automates the imaging process and stores the photos of the imaging run as well which eliminates the need to have a laptop out at the telescope, thus making the setup fully self contained an accessible wireless while you enjoy the warmth of your house (car if at a remote site) and is fairly portable.
So what’s the basic hit for all this glorious astro gear? mind you these prices are not set in stone.
ITEM Average costs
special astro camera kit $1600 New USED $800 ~ $1000
filters $ prices are to varied to list
Telescope $450 New USED $250 ~ $400
Mount $899 New USED $500 ~ $650
Computer controller $180 New USED $150
Other $200 ~ $ 500
Software not added in
Possible Totals $3500 (OUCH) all New gear – – OR – – $2000 (ouch) all USED gear
You will add extras like a guide scope, guide camera, dew heaters, bahtinov focusing mask, extra mount plates and a plethora of other little items that will keep the pockets empty . . . Just like a dSLR kit which seems to always be needing some doodad or other toy . . . gadget . . . oops I mean needed accessory 😉
OK . . . not cheap huh, no but if you pace yourself and watch your pennies you can still do some astro imaging at a small amount compared to buying all new gear. I admit to having more then a few shekels tied up in my gear, but I did make mistakes and didn’t get a full idea of what I wanted to do before I bought. You can do astro photography without going deeply into debt and it will be more enjoyable and the likelihood of it remaining enjoyable is pretty high as well.
So what did I not say or cover, well the learning curve is extremely high, and, extremely complex. Why so you ask? well for one thing you are learning about the gear you just bought, your learning the software that runs it and the software that you use to process images with, then there is the weather and other conditions as well as it being nighttime when you do this (exception being Solar imaging, but it brings its own unique problems)
My setup used for the opening image was as follows
AT60ed telescope, AT60FF field flattener, ZWO asi1600mm Pro camera, ZWO asiMini Filter wheel with ZWO NB filters, ZWO 30mm guidescope with ZWO asi120mm-s guide camera, ZWO asiAIR computer control, Celestron AVX mount with Starsense alignment camera, Dew heater for main scope and guide scope, 12vdc mains power supply for home use . . . or . . . two 12vdc batteries for remote use. Galaxy Android Tablet with Skysafari 6 and ZWO propriety control software.
there where 15 x 300 sec Light images of Ha, 15 x 300 sec of Oiii Light images along with dark and bias calibration frames for a total of 2.5 Hours total integration. Images where stacked in (DSS) Deep Sky Stacker, post processing was in Corel Paint Shop Pro Photo 2019. Photo is a false color image using the following RGB assignments R = Ha, G = Ha, B = Oiii . . .
Other then the time spent in setting up the imaging run (30 minutes from polar alignment to pressing the Start button), I spent the majority of the time watching TV and drinking coffee in the warmth of my house while the asiAIR computer at the mount controlled the imaging run, guiding and capture of the images, I did occasionally take a peek at the screen on the tablet as the captures where happening. I know I’ll be doing a lot of imaging this way. And I know it will make me a lazy Astro Imager . . . but I do so like being . . . comfortable.
I do hope this helps someone not spend money only to become frustrated and give up. Those purdy pictures in those Astro magazines are so misleading . . . it takes a lot to see what our eyes cannot.
Comments are welcome, so are questions. There are people out there that will help if you are interested, but you’ll have to go to them . . . I know I do not have all the answers, if I did I’d have created the universe . . . but, I didn’t . . . This is only the way I do things, Like I said . . . there are as many ways as there are stars in the sky . . .as long as I am learning I am a newbie . . .
I will post a review of my experience with the new (to me anyway) ZWO asiAIR imaging controller, I can say on initial use . . . I like it!
disclaimer: I am not affiliated with any of the products I have mentioned, I am just an average guy who uses them. There are similar products at various cost levels . . . For me I like to keep some of my money for things like food and well you know . . . BEER . . .
Have fun, be inspired . . .
de Digi . . . aka Tim
Oh . . . one last note: I didn’t cover camera / telescope combinations because of FOV, sensor size, and so many other variables that affect functionality and image quality, nor about atmospheric conditions and how that affects seeing . . . it’s all part of the learning curve and the serendipity of Astro Photography, no two nights are the same. In closing here is the 1st photo produced using the entire rig the first night.