# Getting into Astrophotography with Canon Equipment (on the cheap!)



## jrista (Aug 15, 2014)

For those of you who know me, you know I started doing deep sky astrophotography this February. I know a lot of you have expressed interest in the hobby, so I thought I'd share my latest setup. I've learned a lot in the last seven months, including which way is best for setting up a tracking mount for use with DSLR equipment (particularly with Canon's big L-series telephotos, which double as superb "astrograph" telescopes.)

My first attempt, as far as mounting equipment went, was to purchase ADM Accessories' "Dual Side-by-Side Saddle". This is couple pieces of solid, machined metal configured in such a way that it will allow two pieces of equipment, such as a telescope and a guidescope, to be set up side by side on a tracking mount. It looks something like this:











While this got me started, it ultimately turned out to be heavy, difficult to balance, and overall just clunky. It's a better option if you plan to run two identical scopes side-by-side (which some astrophotographers do...they will run two identical setups side by side to either gather sub light frames (just 'subs' for short) at twice the rate, or they will set up each scope and imager with a different set of filters (such as RGB on one side, and Narrow Band on the other) for highly detailed, colorful imaging with mono CCD cameras. 

I recently found some better parts, ones that gave me the option of creating a much tighter, much lighter, more compact, easier to balance and more stable means of mounting my lens to my tracking mount. This setup looks like the following:










































The equipment in the pictures is the Canon 5D III, Canon EF 600mm f/4 L II (with RealTree4 LensCoat, no hood), Orion Atlas EQ-G equatorial tracking mount, Orion 50mm Mini Gidescope, QHY5L-II Mono guide and planetary imager (uses a Aptina MT9M034 CMOS sensor, extremely high 74% Q.E.), an ADM Accessories 15" D-type Universal Dovetail, and a couple of Cradle-type Clamshell Scope Rings from ScopeStuff.

I also used various bits of super cheap hardware from Lowes and/or Home Depot, including large washers, and some long hex-cap 1/4-20 screws to level out the center axis of the scope rings, and attach them to the dovetail. Grand total cost here was maybe ten bucks. 

The total cost of these items (excluding the Canon pieces) was less than $2000 (maybe a little more if you don't find the Atlas on sale), which in the grand scheme of things is extremely cheap for astrophotograpy gear. To really get any better than this, you need to spend more than $2000 on just the mount (and more like $8000 to $25,000), you need to spend several thousand on a good astrograph (a good refracting telescope, one that doesn't even have as large an aperture as the 600/4, is going to run you several thousand at least, and for something with a 130-150mm aperture like the 600/4 is going to run you anywhere from $10,000 to $15,000 anyway; a good RC or CDK astrograph is going to cost you at east a few thousand, if you get something from Astro-Tech...and as much as twenty to eighty thousand for a 12-24" RCOS or PlaneWave). 

If you already have Canon equipment, such as a DSLR and say a 200, 300, or 400mm lens (doesn't necessarily have to be a big L-series telephoto...just any long lens will usually do), then for $2000 or less, you could get yourself a pretty accurate tracking mount and all the other necessary equipment to reliably mount your camera and lens to that mount, with a high quality guiding setup (Orion 50mm mini guidescope and QHY5L-II CMOS camera), which, when set up and handled properly, is good enough for 600 second (10 minute) exposures (which is enough for f/8 telescopes, and more than enough for lenses with f/6.3 or faster apertures.

Now, I personally HIGHLY recommend the Orion Atlas mount, or the SkyWatcher EQ6 (which is the same thing, even manufactured by the same company in China, just a different company). The key benefit with these mounts is the ability to use EQMOD with them, which is very powerful, flexible software that runs on a computer (laptop or windows tablet) and replaces the hand controller. The use of an Atlas/EQ6 is not a requirement, however. If you are not using a large Canon L-series telephoto (the 300, 400, 500, 600, or 800), then you do not necessarily need the capacity this mount has to offer. You could get something like the iOptron ZEQ25, which runs around $800 ($500 cheaper than the Atlas...which in and of itself is enough to cover the QHY5L-II and Orion 50mm Mini Guidescope). The ZEQ25 is a capable mount, it just doesn't have the carrying capacity nor the compatibility with EQMOD. It is more than enough for a DSLR with a smaller telephoto lens up to 400-500mm (say a Canon 100-400, 400mm f/5.6 prime, or maybe a Sigma lens that goes up to 500mm...possibly even the 150-600.) 

So, if you really want to get started with deep sky/planetary/lunar/solar astrophotography, you can do so for less than $1500. That may sound like a lot, and for some of you it may be...but it's actually ludicrously cheap as far as astrophotography equipment goes. If you spend the money, don't regret it. Astrophotography is a complex hobby, and certainly not for everyone...but for those of you who are really interested in getting into it, it is really money VERY well spent.


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## weixing (Aug 15, 2014)

Hi,
Nice setup... I use an old Vixen GPD mount with motor drive... thinking of doing some astrophoto again (that's why I keep my EF 400mm F5.6L when I brought the Tamron 150-600), so thinking of adding GOTO to it... ;D

About the lens, IMHO, most telephoto zoom lens are not suitable for long exposure DSO astrophotograph... reason been most of them have zoom creep due to the heavy front element. I think may be the Canon EF 100-400mm is the only zoom lens that's suitable as it can lock the focal length. 

Anyway, there are a lot of low cost decent telescope in the market now that can produce very good result... IMHO, with a field flattener, most of them can produce better result than most super telephoto lens.

Have a nice day.


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## weixing (Aug 15, 2014)

Hi,
Nice setup... I use an old Vixen GPD mount with motor drive... thinking of doing some astrophoto again (that's why I keep my EF 400mm F5.6L when I brought the Tamron 150-600), so thinking of adding GOTO to it... ;D

About the lens, IMHO, most telephoto zoom lens are not suitable for long exposure DSO astrophotograph... reason been most of them have zoom creep due to the heavy front element. I think may be the Canon EF 100-400mm is the only zoom lens that's suitable as it can lock the focal length. 

Anyway, there are a lot of low cost decent telescope in the market now that can produce very good result... IMHO, with a field flattener, most of them can produce better result than most super telephoto lens.

Have a nice day.


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## alek35 (Aug 15, 2014)

Hi Jonathan,

nice setup indeed. I have a similar setup with a Skywatcher NEQ-5 mount (I believe Orion is the same as Skywatcher here in Europe) mounted with a Eos 7d and a 400mm f/2.8 IS II USM.

Until now I have only tried unguided multiple shots up to 120sec which I have stacked in DeepSkyStacker
and had fair results with M51, M81.

I will be picking up an autoguider while travelling to the US shortly.

One question: have you considered placing the autoguider opposite of the astrograph (i.e. on a secondary saddle) with the counterweights ? 

It would make your setup even lighter...

Cheers,
Thomas


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## jrista (Aug 16, 2014)

weixing said:


> Hi,
> Nice setup... I use an old Vixen GPD mount with motor drive... thinking of doing some astrophoto again (that's why I keep my EF 400mm F5.6L when I brought the Tamron 150-600), so thinking of adding GOTO to it... ;D



At 600mm, you will want something with more than a simple motor drive. The PE on such a thing would probably be horrendous, enough that guiding might even be problematic. The Vixen GPD is a visual astronomy mount, and while it might work for really wide angle lenses, I'd highly recommend getting something more stable with a lower PE for more serious imaging.




weixing said:


> About the lens, IMHO, most telephoto zoom lens are not suitable for long exposure DSO astrophotograph... reason been most of them have zoom creep due to the heavy front element. I think may be the Canon EF 100-400mm is the only zoom lens that's suitable as it can lock the focal length.



Well, having imaged with the EF 600mm f/4 L II for months now, and having seen the poor corner IQ from some fairly expensive high quality telescopes, I can assure you, imaging with Canon's L-series telephotos is a dream. The only telescope that I have seen so far that comes close to the corner to corner field performance of the 600/4 II is the Officina Stellare 150 HiPER Apochromat astrograph. That sucker is as expensive as Canon's 600mm lens, though, and the real kicker? For $12,000 it's f/8!!! (That's like slapping a 2x TC on the Canon 600/4.)

Regarding focus shift, I've never had that occur due to the size of the lens elements. The front element is not actually involved in focus at all. The primary problem with using any kind of large refracting lens for astrophotography is simply the fact that large glass elements change in size with temperature. It doesn't matter if it's a Canon lens, or a legit telescope like the Officina 150 APO. You even have focus shift with SCTs (since they move the primary mirror to focus), and RC's also have focus shift problems due to temperature. Either way, pretty much regardless of what kind or size of scope you have, you will have to deal with focus shift as the scope normalizes with the ambient temperature. These days, though, adjusting focus in between your sub frames is easy, and often a fully automated process thanks to advanced software and robotic focusers.

So, I beg to differ, but Canon L-series superteles are actually EXCELLENT telescopes. They offer superb off-axis star spot size. Which is the reason there are actually quite a few people who use them. There are also professional scientific surveys performed with them as well, such as the DragonFly array, which uses a dozen+ Canon EF 400mm f/2.8 L II lenses to perform ultra high sensitivity, high speed imaging surveys. 



weixing said:


> Anyway, there are a lot of low cost decent telescope in the market now that can produce very good result... IMHO, with a field flattener, most of them can produce better result than most super telephoto lens.



Even with field flatteners, until you get really up there in price, several thousand dollars at least for apo refractors, and particularly in the case of SCTs and RCs, the off-axis performance of Canon's supertele lenses actually outperforms most. I've spent about nine months now on CloudyNights forums. I've seen a LOT of threads on the topic of off-axis performance for telescopes ranging from around one grand to several grand, and sometimes the coma and astigmatism can be VERY SEVERE. Adding field flatterners is not guaranteed to improve things, and if you are not able to get the exact right spacing for backfocus (often the case when using OAG), you can actually make off-axis performance worse.

The Canon 100-400, which I have and have tried to use for astrophotography, is not a particularly great lens. It suffers from quite a bit of optical aberrations at it's faster apertures. You have to stop down to f/8 to get it to perform more ideally (i.e. diffraction limited), however you lose the advantage of using a camera lens when you do that...you've lost a stop of f-ratio.


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## jrista (Aug 16, 2014)

alek35 said:


> nice setup indeed. I have a similar setup with a Skywatcher NEQ-5 mount (I believe Orion is the same as Skywatcher here in Europe) mounted with a Eos 7d and a 400mm f/2.8 IS II USM.



YEah, the NEQ-5 was the prior version to the EQ/NEQ-6, which is the same as the Atlas EQ-G. The 400 f/2.8 L II is a very popular Canon lens among astrophotographers. I think many more have that lens than have anything larger. I think I'm somewhat unique in having the 600, however I think that is primarily a cost-based thing.



alek35 said:


> Until now I have only tried unguided multiple shots up to 120sec which I have stacked in DeepSkyStacker
> and had fair results with M51, M81.



Yeah, with the really wide field of the 400mm lens, you should easily be able to do unguided shots up to maybe three minutes. If you use EQMOD, and program PEC, you might even be able to get up to 5 minutes. 



alek35 said:


> I will be picking up an autoguider while travelling to the US shortly.
> 
> One question: have you considered placing the autoguider opposite of the astrograph (i.e. on a secondary saddle) with the counterweights ?
> 
> It would make your setup even lighter...



The Orion 50mm Mini Guidescope is ultra light. I'm not concerned about the weight of that at all, not now that I have the scope rings. I was worried about it in the past, since my big lens (and the big front element) was just cantilevered out in front. It was problematic, as flexure actually caused me problems. I couldn't get stable stars, and there was differential flexure between the guidescope (which was beisde the lens) and the lens itself, which caused "walking stars" (basically, perpetual drift in RA).

Now that I have the scope rings, both the back and the front of the lens are held very securely. The mounting plate for the guidescope is EXTREMELY tight and stable, and I've also locked down the guidescope itself in it's little finderscope-like holding stand. The last couple of imaging sessions I've done with this new setup have resulted in perfect stars under pretty long (8-10 minute) exposures.

I don't think there is any way I could mount the guidescope on my counterweight bar. Not without engineering something myself to juryrig the thing on there. Not to mention the odd moment that would create, and the likelihood of vibrations in the counterweight shaft. I don't think that would really help things, and it would likely result in more differential flexure problems. I'm not so much concerned about weight as I am about the moment of inertia and flexure. The moment was a lot higher with the side-by-side setup I used originally. It's much, much smaller now, as everything sits right on top of the declination axis. Far more stable. 

Since I get perfectly round stars at up to 10 minutes, I don't think I can really improve things. My guiding performance in my last session was 0.22", which is practically unheard of for anyone using a lowly mount like an Atlas or EQ5/6. I even know people who use the much higher end Astro-Physics Mach 1 GTO, an $8000 mount, or the 10Micron GM1000HPS, a $13,000 mount, who can't get better than 0.45". For the money, I really, truly do believe that a setup like mine is really hard to beat. 

Granted, a mount like the 10Micron 1000HPS can track unguided, and it can do things like counteract wind pressure, recover it's position in the sky after a power loss, etc. My Atlas can't do any of that...but still, it performs remarkably well. I could probably get good stars out of 20-minute guided narrow band exposures if I wanted to...all for a price tag less than $2000. I highly recommend it for anyone interested in astrophotography.


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## NancyP (Aug 21, 2014)

jrista, thank you very much for the primer on a less-expensive equatorial mount, clamps, guiding system scope-camera-software combination. This does sound like a practical and inexpensive entry into AP for those who already have a supertelephoto lens used for other types of photography.


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