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2 months and still not even one decent image - any help will be highly appreciated


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Hi fellow astronomers,

I live in Northampton, UK and quite new in to astronomy (7 months).

Gear:

CPC925 GPS

ZWO ASI 385 MC

8 x 50 default finderscope

Antares f6.3 reducer

Using SharpCap

 

I am trying for almost 2-3 weeks now to take a decent picture (whenever the night skies are clear) of anything....and i do fail consistently. My first real milestone will be to take a decent image of the Andromeda Galaxy....just a decent one.

Some people say that i should move to a refractor (and i am sure they are right) for better DSO imaging, some others say that i should go for a scope guider for longer exposures, some say both. What i am looking for here is a simple way to use the equipment i have to take some decent photos with my daughter at the current beautiful UK skies.

I have even read the beginners guides in these very great forums but, it seems that i do not get it. I guess i am asking for help to setup my gear correctly - is there somewhere that i could get that service/ advice?

 

Many thanks in advance

George

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I would try to get what you can from your existing gear first.

M27, Dumbell Nebula would nearly fill the FoV.

It is also quite colourful.

https://astronomy.tools/calculators/field_of_view/?fov[]=112||1131||0.63|1|0&messier=27

M51 Whirlpool is a pair of merging galaxies

https://astronomy.tools/calculators/field_of_view/?fov[]=112||1131||0.63|1|0&messier=51

Planetary is also an option.

Or more advanced would be to do a mosaic, not so straight forward.

 

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I'm 4 months in and haven't captured a decent image yet. It's not easy. I don't think that there is any instant gratification in this hobby, it's all about learning and improving in incremental steps. There are rigs like Stellina Meet STELLINA, our observation station | Vaonis which are designed to produce good images without all the frustrations. It looks like your kit is quite capable.

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I started taking some shots with the smartphone placed near the telescope eyepiece (an 80/400 refractor) to photograph the Moon in the first quarter, the eyepiece I used was a 10 mm Plossl. Last year at the end of July I got a photograph that I don't mind. A few months ago I bought a used Celestron Nexstar SE 8 that I am learning to use, I saw that I should collimate it. I would like to learn to photograph the Moon and planets with a webcam or something similar to propose it to my students next school year (I presented an astronomy project at school). Slowly …....

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Hi

By far the easiest way would be to get someone over who has some astrophotography experience and see if they can do anything with the stuff you have. Take careful note if what they do. The way in is the local astro club. 

If your stuff isn't going to work, you'll then be able to see first hand what is suitable by attending their sessions.

I think however you should be able to get a decent shot of part of the moon quite easily with what you already have. One thing you could do is to get close to infinity focus during the day on a distant object with the camera at low gain.

Cheers and good luck.

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Concur. Just getting pointed at a target with that small field of view is no small challenge. There is all manner of tech to recommend but I think that would snow you pretty deeply at this point. My recommendation is to do exactly as alacant suggests, then once you've got focus nailed, at night  you can figure out exactly what you're pointing at by uploading your frames to nova.astrometry.net. It's a slow process, but very easy. Eventually you'll likely end up with kit that lets you do it locally, in seconds. but just getting focused and on a target will be enough of a triumph. Heck, once you've got it focused, slew it over at the Milky Way and shoot a few! Plenty of tasty stuff in there.

A possible deep-sky target with your rig, once you have focusing and pointing figured out, is M57, the Ring Nebula in Lyra. It's high in the sky, and it's pretty bright, so your tracking/autoguiding game needn't be Hubble-level to get enough photons for a recognizable image. It's tiny, so most deep-sky imagers don't get to it till much later, when they graduate to 2000mm focal lengths. 🙂

I  am reluctant to tell someone "you're using the wrong gear, you MUST use what I use".  That said, I did follow the "standard advice" of  a short focal-length, fast refractor and a big sensor to start with and I'm very happy that I did. Deep sky is a tough game and no mistake, even when you go the easiest route you can find.

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I see you have an Antares reducer in your imaging train. Have you set the correct back focus? This is the distance from the reducer to the CCD/CMOS chip in your camera.  Depending what you read, the antares back focus is either 105mm or 82mm.  The ASI 385 has a focal distance of either 7.5mm to the face plate or 12.5 with the adaptor so you'd need to add on some extension tubes to get the correct distance. 

You don't say what's wrong with the images you've taken so far. If you post a few on here, the experts may be able to tell what's going wrong.

Graeme

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Firstly Iapa has hit the nail on the head. Even with focal reducer your long focal length telescope has a tiny field of view with your camera, so you need to begin with an object which will fit on the chip.  For this you need to be able to model your setup on a map of the sky - a PC planetarium. Iapa used Startools. I can't help because the one I use is out of production. Perhaps others could advise on alternatives?

The first step in taking an image is modelling it on a sky chart in this way. As you've seen, all you'll get on Andromeda is a featureless fuzzy patch of light in the core.

An enjoyable way to start might be to try the colourful double star Albireo, the neck of the Swan in Cygnus. It will work in short exposures, is easy to find and will easily fit on the chip. It will also give you an insight into trailing caused by tracking error and how long an exposure you can get away with.

273572568_ALBIREIOfinishedweb.jpg.03e776e75c5fda238fb73e0489bc502d.jpg

Good point about backfocus from Graeme, above, as well.

Honesty corner: I would not throw money at trying to make the CPC work for deep sky imaging. A few succeed, the majority give up and move to a more suitable focal length and equatorial mount. Years ago I spent time and money on trying to image with a Meade equivalent and made no progress till I switched to a German equatorial and a small refractor, autoguided. Then it was great.  (Given the small pixel size of modern cameras it is even more true that we don't need huge focal lengths any more.)

Olly

Edited by ollypenrice
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2 months without a decent image - dont stress! As my son said, 'why do you do such hard things Dad?' Astrophotography is a hard game, period. You have picked an epically hard set up to start but you will get great images. I started with, and still use a telescope imaging at 911mm, without any GOTO, so manual finding targets, and no tracking. Now 3 years later, it is all fully automated, I decide what I want to image, check focus, then press a button and go to bed, get up in the morning with a neatly parked telescope and hard drive full of data, lovely. But every step took months of hair pulling, research, and fail,fail, and fail again. Sounds like you are ticking the trying box. Your local club will be a huge asset but as others have said, 1st step focus, then select a good target (moon is a nice obvious start). Every time you get an image of something you cant see revel in it, don't expect Hubble quality, just be amazed at what you can image from your back garden in the UK. If you don't understand what the issues are with your image put it up here and others will be able to advise.

Welcome to the club!

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Hi George

Your main expense - the CPC925 - is ideal for Planetary imaging with a Planetary camera.

For DSOs the CPC925 with FR needs a larger chip camera to use it's full field of view, so consider short exposures with a cheap DSLR such as the Canon 600D, which is simple to use.

Or sell up and start over with an EQ mount and a refractor...........

Michael

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Team, thank you so much for your input & advice.

With loads of trial and error and eventually through small wins i should get there. I will try tonight some planetary imaging to help with the morale. Also, i will take it out again this afternoon to check (again the focus).

Here are some of the 3-mins frames i got last night from the Andromeda galaxy. 

andromeda_00001.fits andromeda_00005.fits andromeda_00011.fits andromeda_00017.fits

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28 minutes ago, George Sinanis said:

take it out again this afternoon to check (again the focus).

Here are some of the 3-mins frames

Looks good. You're in focus:)

Maybe try m13? Should look good at that focal length.

 

Edited by alacant
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4 hours ago, George Sinanis said:

Here is the stacked image......

andromeda_00001.bmp 6.07 MB · 11 downloads

You have imaged the core of the Andromeda galaxy - 2.5million light years away, awesome! There really isn't much more detail to be had out of the core, especially in only a few minutes of subs (at my f4.5 and light pollution of bortle 8+ I image most targets for 8-12 hours!). That's just about what I got out of my kit to start, similar long focal length. I moved to different things because the target just wasn't suitable for my focal length. I bought a 388mm fl refractor for imaging Andromeda  (another journey of pain and suffering, lol). Your goto is working, that's a good start. I would try a few other targets, M51 whirlpool galaxy, dumbell nebula - just a single sub seeing those got me excited, so it wasn't all just grind. Planetary is a whole new ball game, your rig is more suited to that, but a totally totally different process.

Hope we see some more of your shots and good luck!

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Quick question: should I try with a used Astro-modded canon dslr (450, 550 or 600) that are for sale for £200 at the classifieds of this forum? I was thinking of trying with a dslr and use the zwo asi 385 as a guide camera. At least to try. 

Edited by George Sinanis
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4 hours ago, George Sinanis said:

Quick question: should I try with a used Astro-modded canon dslr (450, 550 or 600) that are for sale for £200 at the classifieds of this forum? I was thinking of trying with a dslr and use the zwo asi 385 as a guide camera. At least to try. 

My suggestion is dont make it more complex attemping to buy more equipment at this stage. You dont need guiding to get decent images. As others have already suggested go for the moon, planets and the easier DSOs like M81, 82, M13. Use a software like Stellarium and configure it to add your scope and ASI385 to get a preview of which objects will fit into your FOV.

I started imaging just a few months ago with a scope that is more basic than yours. Learn how to use the Nexstar software that comes with your scope to setup, polar align and then get accurate GOTO tracking. Remember that with imaging, half the hard work is in stacking & post processing to extract the details out of your stacked image. So get a good software that can do that. There are several out there like DSS, Autostakkert etc. I use SIRIL which is free and runs well on my linux PC. My thread showing my images is here (in case your are interested in seeing what is possible for even a beginner 🙂 ). Good luck!

 

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Looks like you bought the Ferrari and now you're trying to figure out how to tow a trailer. Buying a towing hitch might seem like the obvious solution but it's not really the way to go!!! We all did it. 2000mm FL sounds fantastic but it is sooo hard to work with.

What you do have is a very nice planetary imaging system. (long focal length; alt/az mount; non-cooled camera; no guiding kit; Sharpcap software). All designed for planets. It's not impossible to image DSOs with it but it will be difficult, and nobody on here would recommend that you start with this setup. But given that's what you have, and if you really want to do DSOs.... there's good advice above. Mainly, figure out which targets will fit in your field of view (they need to be small and bright) and work from there. I'd recommend Stellarium planetarium software to figure out what targets will suit. 

It will be practically impossible to image Andromeda with it. I have a 400mm refractor, and I'm planning a two-frame mosaic when Andromeda is next in a good position for me.

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What do you call decent ? Just in case your more picky than me. I've been doing this about same as you (5 months with scope, last 3 months doing AP).

Took the following last night and pretty chuffed with it.

Here a few others I've taken the last 3 months or so. If those pass as decent for you, happy to give you the advice of a one eyed man in the kingdom of the blind.

253606939_IC434.newaftertutorials.thumb.jpg.6cfd97e2b56ffce4a4c3035d5c5a42e4.jpgm51_21_05_10.jpg.e6b12a4bfc2ad002ed63c109a968f351.jpg

25.03.Rosette-RGB-session_1-St.jpg

1303.orion.jpg

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1 hour ago, powerlord said:

What do you call decent ? Just in case your more picky than me. I've been doing this about same as you (5 months with scope, last 3 months doing AP).

Took the following last night and pretty chuffed with it.

Here a few others I've taken the last 3 months or so. If those pass as decent for you, happy to give you the advice of a one eyed man in the kingdom of the blind.

253606939_IC434.newaftertutorials.thumb.jpg.6cfd97e2b56ffce4a4c3035d5c5a42e4.jpgm51_21_05_10.jpg.e6b12a4bfc2ad002ed63c109a968f351.jpg

25.03.Rosette-RGB-session_1-St.jpg

1303.orion.jpg

Mate these are beyond decent...these in my eyes are...WOW! I wish we could come even close to these. Well Done!

 

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So, advice help wise - what are you finding ? are you ok setting up your mount ? aligning it (its an AZ one I think ?).

I reckon your main problem is you have a massively powerful OTA at 2350mm on an AZ mount. Its really for visual stuff.

You're just not going to be able to get long exposure on that I doubt at all (by long I mean say, 2 mins or so). Can you even get 30 seconds ? I started with a mak127 which is 1300mm and and azgti in az mode,and was lucky if I could get 20 seconds or so. you have double the FL.

And of course the problem with those celestron jobs is you can't just get another OTA and pop it on.

IF you want to do stuff that involves taking pics of nebula and the like, you might be better selling what you have, and getting something like an AZGTI and wedge. That's the cheapest way into EQ goto astro. And get a more widefield OTA - something like an 80ED ? That will get you great views of moon, DSOs, etc. And with your camera on the back you should be able to get 2 min+ subs easy with the AZGTI in EQ mode. No need got guiding, etc for that. And the AZ GTI will cope with other scopes later if you want them - say a mak127 like mine, etc.

That'd be my advice anyway. The good news is the market is so bouyant just now you will get a good price for your current kit.

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