Astrophotography - building a new system - advice welcomed

[To The Universe And Beyond]

Hi – newbie potential astrophotographer here. None of the gear but some ideas which I’d really welcome you views about.

What I’d like to work up to over time is to build an astrophotography system with the ability to take high quality images of nebulas, galaxies and the planets, in that order. Being retired from the NHS I’m on a pretty limited budget, so I’m thinking of going the second-hand route over the next 12-18 months, but part of me is tempted to sell some camera lenses and a guitar (or two) to go all in and try and build a complete system from the start – mount, telescope plus their bits, guide-scope and a mono ccd module. I have a laptop and I’m competent in photo-manipulation software so at least that bit feels dealable with.

I’ve worked out perhaps the key component for astrophotography is a decent mount. I want to operate from my girlfriend’s back yard, in which case perhaps something like a Skywatcher EQ5/6 might be suitable. But due to local light pollution I’d also like to visit some darker sky sites from time to time too. In which case, how realistic/easy would it be to chuck an EQ5 in and the rest of the gear into the boot of the car and set up everything in a field in the middle of winter? Do people do that, or is setup time, lugging lots of weight, the need to avoid freezing to death etc just not worth the hassle?

Is buying a mount second hand a sensible option at all, bearing in mind what can go wrong with goto mounts which are full of gears, electronics, lubrication need etc, all of which need to be working well in order to be useable?

Telescopes – would a more compact refraction telescope be a good starting point? Coming from general photography I know the importance of good glass. I’m not clear whether a shorter focal length telescope with very good optics e.g. RVO Optics 72 (a Williams Optics clone) might still enable me to get decent images of galaxies as well as nebulas using a lower-end CCD module and guide-scope? Or would I simply need something with a significantly greater focal length?

Cameras – I do have an excellent Sony A7R III camera generating 42mp images which I could use as a starter dslr-type camera on the end of a telescope, but it has the Sony “star-eater” curse, in that Sony uses aggressive noise-reduction algorithms which can’t be disabled by the user for anything over 3.2 secs exposure and which erases a significant number of stars in long exposures. Thanks, Sony. Consequently, I can’t find anyone on Google using these cameras for longer-exposure astrophotography through a telescope. Am I right in thinking a max limit of 3.2 sec for image stacking is not going to be long enough for deep-sky imaging?

Similar question about buying ccd modules second-hand– minimal info out there about reliability of CCD modules and their likely lifespan/reliability if buying second hand. Any thoughts? Given how quickly technology moves on, any unusually good performing ccd modules recently arrived that could be recommended in the “cheaper” end of the market? Not too much info out there apart from lots of people showing stunning images from £1kplus ccd kit.

I’d really welcome all views about the above. I think astrophotography is going to be my last big project so I want to try and get as much right from the start as possible.

[Kyle Allen]

You’re right to ask lots of questions before rushing in and buying lots of equipment that you find you need to upgrade later down the line. Have you read the book Making Every Photon Count? It is aimed at beginners to astrophotography and talks you through all the equipment you need to get started as well as image capture and processing techniques 😀

[endless-sky]

Hi,

I, just like you, recently started my journey into astrophotography. I can't answer all your questions, but I'll try to tell you what I can / figured out along the way.

As you said, the mount is the most important piece of equipment, when it comes to astrophotography. The best optics in the world would be useless if the mount cannot support them and track correctly. The minimum I would buy is a HEQ5 or equivalent. But with the HEQ5 you really cannot go wrong. I was searching for one in the used market, but I got lucky and I found a NEQ6 Pro for the same price I was willing to pay for the HEQ5, so I went with that instead. I don't think buying in the used marked is a bad idea: people in this hobby are pretty careful with their equipment, knowing how much it costs and cherish it quite well. Just watch out for scammers - unfortunately they exist in every field. As far as portability goes, sure the NEQ6 Pro is heavy, but I was able to take it in a dark site in the mountains without problems. The only problem is having a power supply source - like a car battery or similar - but this problem is not specific just to the NEQ6 Pro, but you will have it with every motorized mount. I have been very happy with my choice of mount, it can track without star trailing for 2 to 3 minutes, at 300mm focal length, with a D5300 DSLR.

As far as the telescope goes, I can tell you what I have read so far on many forums and the same route I plan on going: a fast 80mm apochromatic refractor (f/6 or lower). So far I have been imaging with my Nikkor 70-300mm, but being a zoom lens it suffers from all sort of problems (geometric and chromatic aberrations, tilting, slow lens). I pretty much exhausted the possibilities this lens can provide me. I first thought the problem was mostly mine (not being able to process the images, once acquired, mostly), but then I tried with a prime 50mm lens and the results - despite being a larger field of view - were light years ahead (excuse the joke...) of all the other pictures I took with the 70-300mm @ 300mm. Stars perfectly round, no aberrations whatsoever. So, I decided that my next step will be to buy an 80mm f/6 apochromatic, so I can finally take the quality of pictures that I know my mount and my processing abilities are able to deliver. I think, if you go this route, a "must" is also a field flattener or a flattener/reducer, otherwise stars will lose their round shape the further they are from the center of the image. Personally, I will go with the flattener/reducer, because I don't mind trading some focal length in order to make the telescope faster (with a 0.8x reducer it will become f/4.8, which translates into more light collected in the same exposure time, or, another way to put it, less exposure time for the same amount of light). Unfortunately the good for everything telescope, as far as I know, does not exist. So at the beginning you will have to make a choice: do you want to capture wide nebulae or small and distant galaxies? You cannot do both with the same focal length telescope. With the tool provided by this website - https://telescopius.com/telescope-simulator - you can input the focal length of the optics and the size of the camera sensor and it will give you an idea of how much of the framing each object you type in the search box will take up. Personally, I mostly like wide nebulae, so the 300-500mm focal length range gives me the best options. The scope I have in mind is an 80mm f/6 (480mm focal length), reduced by 0.8x to 384mm. Combining that with the D5300 sensor size gives me nice framing on a lot of targets, so this scope will keep me busy for a good while. Galaxies will have to wait, as the longer the focal length the more difficult imaging becomes (everything is magnified, including the tracking errors - you will need guiding, in this case). With a short refractor and a good mount you can get away without guiding.

For the camera, I have a Nikon D5300, so I really cannot help you about Sony. I am very pleased with this camera, the noise level is very low, it has high dynamic range, and it is "isoless", so I can image at 200 ISO, taking advantage of the dynamic range. I have to point out that I "astromodified" the camera - procedure that I undertook myself, but there are some companies that can do it for you, for a price - by removing the stock filter placed in front of the sensor, and putting an IR/UV cut filter in its place. This is pretty much necessary if you want the camera to have a good response in the H-alpha line of the spectrum (which is pretty much every other nebula...). Natively, these cameras, meant for daytime use, are not responsive enough to this part of the spectrum, which means you would need to integrate longer exposure sessions to get the same results. Time and clear skies are a rare commodity as it is, so I preferred to modify the camera, to use it to its full potential.

So, you really do not need to start with a dedicated astrophotography camera. But if you think about buying a new camera because of the problems you have with your Sony, it might be worth it looking into one. I would advice for a OSC (one shot color) camera, though, not a monochromatic, at least from a beginner's point of view. There are a lot of things to learn and sort out at the beginning, adding the complications (and the expense) of a set of filters, and having to image for multiple nights on the same target - remember, clear skies are a rare event! - to compose a color image would just increase the level of difficulty.

I hope I could help you in your choices! Whatever you decide, clear skies!

Matteo

Edited June 7, 2020 by endlessky

[endless-sky]

Another thing: I just remembered you said you have a lot of lenses you would like to sell in order to fund buying your setup. You could always buy the mount first, get your feet wet - like I did - with some of those lenses, to see what results they are able to give you, just using your Sony. If you don't like the results, then you go replacing piece by piece. The more things you add to the mix at once, the harder it is to sort out what is causing the problems. Beside mount, optics, and camera, there's also the software perspective to sort out. It is a very steep learning curve, at the beginning, when you have all these things at once. But it's worth it. When that first picture you took - despite all the defects it may have - will show up on the screen of your PC, it will give you an immense joy. YOU took that picture, with YOUR equipment, and YOUR skills. And, as the last two improve, so will the pictures!

[Waldemar]

I second Kyle Allen. Buy the book : 'making every photon count' and learn before you leap, so you have to buy only once and cry only once...😱
 

[To The Universe And Beyond]

Many thanks for your thoughtful replies.

Kyle Allen - Have you read the book Making Every Photon Count?

I've been trying to track down an affordable copy (Amazon £49.99!) but the publishers aren't posting anything out currently due to lockdown.

endlessky - Really helpful to hear that using the HEQ5 or even the NEQ6 Pro in the field is manageable - I'm more inclined than ever to look for one of these at this point. I'm still a little wary of purchasing second hand but you're right - the vast majority of astronomy enthusiasts are likely to nurture their expensive gear rather than abuse it. Interesting comments about focal length. I's already factored in my thinking the need for a field flattener as something essential for Astrophotography whatever I end up getting. Even though I know there's no one-telescope-does -it-all option out there, trying to identify x2 aaffordable telescopes to cover the bases still feels really difficult for me currently.

Think the next option for me, unless miraculously I come across an excellent and affordable second hand package somewhere, is to get a quality mount and then find out  just what I'm able to  get from my Sony mirrorless with different lens combos.

When I mentioned getting a mono CCD I was initially thinking about how to extract the best possible data for imaging. You mention a really good point which hadn't occurred to me though - multiple nights shooting the same image with typical UK weather may not be the best choice for me - will look again at colour CCD options.

.....it's worth it. When that first picture you took - despite all the defects it may have - will show up on the screen of your PC, it will give you an immense joy. YOU took that picture, with YOUR equipment, and YOUR skills. And, as the last two improve, so will the pictures!

Well said, endlessky!

[Kyle Allen]

You can get the book for £20 from First Light Optics (the forum sponsor) 😀

[Kyle Allen]

You might want to decide on the camera before deciding what scopes will be suitable for different objects because different cameras used with the same scope can produce different fields of view

[carastro]

Wow lots of questions there.  Better answer the first few before I forget them, so haven;t read the 2nd part of your post.

HEQ5 would be preferable to an EQ5.  Depending on what telescope you decide to buy an HEQ5 will do most refractors and small Newtonians.  

In normal circumstances (not during Covid crisis), I pack up all my gear and go monthly to a campsite in East sussex along with some other astro chums and camps for a few nights.  It is more fun if you can do this in a group, and the cameraderie makes the effort worthwhile.

You need different telescopes and cameras for doing planets and Deep Skly objects. 

I will now go back and read the rest of your post.

Carole  

 

Edited June 7, 2020 by carastro

[carastro]

Whoa!!!  Sony A7, that's a to die for camera if its anything like the Sony A7S excellent for broadband photography.  You may or may not know though that to get the best out of DSLR cameras, they need the IR filter removed.  

Quote

 it has the Sony “star-eater” curse,

Oh dear.  But the person who I know has an A7S does really short images because of the incredible sensitivity, and I think he has overcome some of the problems with this camera.  It might be worth having a talk with him, he is a member of this forum and always very helpful (Sharkmelley).  

I think a decent refractor not a long focal length is a great choice for starting out.  If you want to take a look at my website (in my signature) you can see the images I have taken with William Optics ZS71, and a Skywatcher ED80, (as well as a couple of other scopes).  Long focal length puts more demands on the learning imager and gives a smaller FOV anyway. 

As regards CCD cameras, I would personally recommend a mono camera and filter, costs more, but more sensitive and a bit more involved in processing, but also give the option of narrowband in your LP home location.  I am currrently stuck at home in Bortle 8 and would not be managing at all without narrowband at the moment.

HTH

Carole  

 

Edited June 8, 2020 by carastro

[To The Universe And Beyond]

Hi Carole - those are wonderful images on your website which are exactly the kind of image I would hope to make myself one day. Especially impressed with the skywatcher ED80 images - just shows what's achievable in the right hands. Do you think this might be a sensible option to cut my astrophotography teeth on as a ?

Unfortunately the Sony A7S has a completely different imaging good all-roundersensor to my A7R III - shame - and 2nd hand prices are still very high despite this being a relatively old mode which Sony have yet to replace.

Back to mono CCD consideration - think you're right - narrowband and LP issues very relevant to me.

That astro-camping in East Sussex sounds a great idea - let's hope we're all in a better place in a few months time to be able to consider this kind of thing again.

[To The Universe And Beyond]

Kyle Allen -You can get the book for £20 from First Light Optics (the forum sponsor)

Thanks - have ordered a copy. Let's hope I can do a better job tracking down some distant galaxies in the future better than I did with that publication :).

[Skinnypuppy71]

Hi..I'm pretty much in the same boat as yourself....also have a Sony a7....the original one  and not the R model....although I've just went and ordered my kit (after the sale of my motorcycle, I no longer used).I went for a eqm-35 pro goto mount instead of the heq 5, as I really wanted a nice apo refractor and couldn't quite stretch to the h-eq5 as well as the refractor, a William optics z73 is what I went with along with the field flattener and a few other bits n bobs...still haven't received my load of goodies yet...I will probably get the heq 5 at some point....when I've learned more and feel ready to work with larger scopes /guiding etc...but this hobby ain't a sprint....it's a marathon and the eqm-35 will quite happily track with this size of refractor /camera or camera /lens...it's also modular and the declanation part  of the mount can be removed to make it more portable and works more like the star adventurer in this configuration....I'll keep you posted whenever it finally arrives...I'm sure the lockdown has something to do with despatch and logistics for this type of equipment.

Edited June 7, 2020 by Skinnypuppy71

[To The Universe And Beyond]

Hi Skinnypuppy71

I wondered about the eqm-35 myself but thought I'm more likely to move towards heavier and larger gear as time goes on so a larger mount is probably going to be best for me. That Williams Optics Z73 dose look really nice for a high quality and portable/more manageable for a newbie telescope. Did you consider the Rother Valley Optics RVO Horizon 72? Think they've attempted to clone the WO design but with similar sounding good optics and possibly better focusser etc. Couple of v positive reviews on pdf from their own site but can't find any user experience accounts of the RVO Horizon anywhere though.

[Skinnypuppy71]

Yeah..had a look at the rvo  frac but I've been persuaded by Astro backyard guy...he likes his refractors and pretty much swears by the Williams optics kit and I'm a suker for nice build quality and pride of ownership....if your into cameras and lenses...you'll know what I'm on about.lol...oh and the eqm-35 is me stretching it from planning to buy a star adventurer....so the h-eq5 is a few years down the road for me I think...and I really hate the idea of spending nearly 800quid on a glorified tri-pod....I love glass.lol....but if you're planning heavier loads in the future, the h-eq5 would make more sense....me I think I'll be quite happy imaging with a small refractor and observing with a 150-200 newtonian....which the eqm-35 should manage, hopefully!

Edited June 7, 2020 by Skinnypuppy71

[To The Universe And Beyond]

Sninnypuppy71 - yes, know what you mean about 800 squids (+) for a glorified tripod - especially one that leaps around of it's own accord! And yes, good build quality for glass and pride of ownership. Although the price of of the Sony GM lenses make a lot of telescopes look cheap! Considering selling my soul to get some astro gear at this point since not much else left. I've got a bad demographic regarding potential Covid mortality so hoping the distraction of a major new interest in something I can do alone if needed will help with morale and mood, without necessarily turning into a hermit! Will deal with the pale-skinned night creature/newbie astronomer issues another time

Let us all know how you get on when your EQM-35 arrives and hope you get hold of it soon.

Edited June 8, 2020 by To The Universe And Beyond

[carastro]

Quote

skywatcher ED80 images - just shows what's achievable in the right hands. Do you think this might be a sensible option to cut my astrophotography teeth on as a ?

It is much recommended as a starter scope for astrophotography - it's a good weight and focal length and doesn't place huge demands on you or your guiding when you are learning.  I would get a focal reducer to go with it as this helps to bring down the focal ratio to something a bit faster.  

The alternative would be one of the William Optics smaller scopes which have excellent optics (I have one) but I find the mounting of it less good than the Skywatchers, with a silly little foot so you can't balance without having to add a further dovetail, and no-where to mount a finder, but I think some models are better than the one I have so just be aware what to look out for if you decide to get a William Optics.  I think there are also small refractors made by TS and Altair Astro, but I have no experience of them.  If you want to go up market for a triplet I think the Esprit scopes are also good for a beginner.  

So basically the ED80 is a good start, or something similar, just make sure you get an APO to avoid chromatic aberration.  

You would be welcome to join us at our East Sussex camp once everything gets up and running again, which I don;t somehow think will be until 2021.  PM me if you want to be added to the E mail list.

As regards buying a 2nd hand CCD camera.  I have 3 times bought 2nd hand and they have been excellent, one I am still using right now.  It just depends who you buy from.  Best to buy from either some-one you know, or some-one on this forum who has a good reputation he/she doesn't want to lose.  

Carole 

 

Edited June 8, 2020 by carastro

[alacant]

11 hours ago, carastro said:

It is more fun if you can do this in a group,

Hi

+1. No need to fumble around alone aimlessly in the dark!

You also have the opportunity to see others operate their equipment first hand, something which no amount of research and reading will get you.

My advice would be to make your choices after you've seen the gear first hand.

Cheers

[To The Universe And Beyond]

So much good advice - thanks to all. Lots to think about.

 Carole  - your website is amazing - so much useful information for beginners and experts alike - https://sites.google.com/site/caroleastroimaging/home

 

[Ags]

15 hours ago, Waldemar said:

have to buy only once

But dreaming, shopping and buying is half the fun!

Also, even if you somehow get it perfectly right and you have an ideal setup, it can't cover all the bases and you will inevitably need to do a bit more buying 😀

[To The Universe And Beyond]

Too true!

[nfotis]

I am in a similar situation (but without a car). So, I may test the waters with a Mak 127 first (on a camera tripod).

If you wish to move around and loading/unloading the mount/tripod in the boot, I would avoid going heavier than the HEQ5 - this seems to be the practical limit for a single person to carry (if I remember correctly, the mount is around 16 kg, the tripod adds 10 more, not counting the counterweights). In the EQ6, the mount alone is above 25 kg, I think.

Are you sure that your Sony can't be 'persuaded' to give you a RAW file without being pre-processed?