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Peco4321

Is this really the best I can achieve?

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Hi everyone, just after a bit of guidance, I know for good DSO images you need tracking and a good understanding of post image processing via stacking and other methods, but is there anything I can do to improve what I have here.  Basically all I can get is 2 sec exposures at prime focus, 150p on eq3-2, and even then, focus isn't great and star trails are starting.  I am quite proud of where I have come in a short time, but want to improve these pictures.  Andromeda is a fantastic sight with a great story, but I just can't do it justice.

I have managed to get better focus of Polaris due to it not moving much in the sky, picture attached, so am hopeful with tracking I can improve, but till then, any suggestions greatly appreciated.  I don't really see any benefit in stacking as I doubt much can be done.

Thanks all,

Peter

IMG_7900.JPG

IMG_7855.JPG

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It might well be, if you have no tracking/guiding going on. Have you seen the No-EQ Challenge thread?

Might give you some guiding and ideas of what you might be able to get. You could try some photography with just a prime lens on a DSLR for wide shots - you can get longer exposures with the shorter focal length of a camera lens - but with your 150P you will get trailing very quickly without any sort of tracking/guiding.

Having said that, you can get A LOT of 2 second exposure over an evening, so why not try stacking what you can get and see how you go on? Nothing to lose at all. 

I certainly found things improved greatly when I put motors on my old EQ3-2 and then , later, with an NEQ6 and guiding, the sky is literally the limit - now all I need to do is figure out the processing - how hard can that be! :-)

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1 minute ago, Marky1973 said:

It might well be, if you have no tracking/guiding going on. Have you seen the No-EQ Challenge thread?

Might give you some guiding and ideas of what you might be able to get. You could try some photography with just a prime lens on a DSLR for wide shots - you can get longer exposures with the shorter focal length of a camera lens - but with your 150P you will get trailing very quickly without any sort of tracking/guiding.

Having said that, you can get A LOT of 2 second exposure over an evening, so why not try stacking what you can get and see how you go on? Nothing to lose at all.

I certainly found things improved greatly when I put motors on my old EQ3-2 and then , later, with an NEQ6 and guiding, the sky is literally the limit - now all I need to do is figure out the processing - how hard can that be! :-)

Thanks for that, I know what you mean about processing, it's an absolute minefield, I really do not know where to start, oh hang on, yes I do, searching this place for advice lol.

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Definitely, this is the place to start and, if you are anything like me - start of simple, with something like Deep Sky Stacker and curves and levels in PS or GIMP - don't launch straight into something like star tools or Pixinisight without a little bit of the basics under your belt... in my opinion of course - everyone is different! Just keep at it and it will come eventually!

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I think the cruncher here is the lack of tracking which is why you have star trails even in very short exposures. Your focus by the way looks spot on so you are doing fine there. Until you are in a position to either motorise your mount in right ascension (RA) or upgrade to a motorised mount, you will have to accept the limitations that this imposes. But, continue as you are and take lots of exposures of brighter objects and stack them in free software like Deep Sky Stacker (DSS).

You could also consider taking the telescope out of the equation for now and taking widefield images of the Milky Way using just your camera and the widest camera lens that you have.

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100% agree with the advice given. With no driven mount, short exposures of bright objects through the scope is the way to go, but if you have a wide angle lens, stacked short exposure images of the Milky Way can give some very pleasing results.If the imaging bug really bites, I thoroughly recommend getting hold of a copy of Steve's book 'Making Every Photon Count' and also soaking up the wealth of information and advice available here on SGL, before making any upgrades to your set up.

Clear Skies

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Just watched that video and now trying DSS, so lets see, oooo, the anticipation.....

update- not much better though I think I know a bit more about DSS, so thanks for the heads up on that video. 

Edited by Peco4321
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maybe a skywatcher star adventurer? relativly cheap and will track plus you will only need your dslr and can do widefield also

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You have the Skywatcher EQ3-2.  Why not just fit an RA motor to it for tracking? Then as long as your polar alignment is very good, you should be able to get decent length exposures.

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1 minute ago, Davesellars said:

You have the Skywatcher EQ3-2.  Why not just fit an RA motor to it for tracking? Then as long as your polar alignment is very good, you should be able to get decent length exposures.

RA motors are on Xmas list, just trying to do the best I can in the meantime.

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An RA motor will make a huge difference but please be aware that using an EQ3-2 mount to drive a 750mm focal length scope is going to be tricky. It can be done but your exposure times will be quite limited and you can expect to discard a large percentage of subs due to uneven tracking. On the other hand, it does work very well with camera lenses, here's my Andromeda & Triangulum taken with a 50mm lens:

22225098393_642bed555f_b.jpg

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Budgetastro.net good place to start for a processing intro. Can use GIMP to pretty much replicate what shown.

Another fan here for using a dslr and lens. Taking the telescope out of the setup, it's big a wind sail and at this stage I think cause more frustration then productivity.

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For what's it's worth, here's my DSS processed image of 10 lights, 5 darks and 5 bias but not sure enough data there. Anyway, at least I am getting to know the lingo ?

image.jpeg

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I have an EQ3-2. The mount is capable 60 second exposures if it is driven and well set up, although you may have to discard a percentage of frames, you can get add-on RA motors for these mounts.

I don't think using the 150P is over-optimistic, I took this pic using my 1509PL which is 1200mm fl on mine a few weeks ago:

M27 Dumbell Nebula.jpg

The tripods are a bit floppy, a bit of studding to clamp together the two supper parts of the legs helps, but I got an EQ5 tripod in the end which I use with the EQ3-2 mount.gallery_43529_3785_50869.jpg

Edited by Stub Mandrel
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Worth remembering the rule of 400 for exposures with no drive (some use 500, but it's pushing it). Generally, you can get away with an exposure time of 400 seconds divided by the focal length of your lens or scope in mm. So a 50mm lens will give a 4 second maximum exposure, while a 150P will give approx 1/2 a second max before star trailing becomes a significant problem. However, there are a couple of caveats:

1) This "rule" was designed for 35mm cameras - with modern DSLRs you typically have a smaller sensor, so you should still expect some star trailing.

2) It doesn't hold as well at longer focal lengths (and I mean over about 100-150mm). You need to cut the exposure shorter than the rule of 400 suggests.

With a 150P and a DSLR you would expect star trails from about half a second up - you really need a drive for anything other than wide angle sky shots.

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30 minutes ago, Knight of Clear Skies said:

Nice image of the Dumbell there, but bear in mind it has a much higher surface brightness than Andromeda.

I just chose that as it was recent, the EQ3-2 is fine tackling fainter targets.

Here's an Andromeda on the EQ3-2 using a Canon 10D which isn't very sensitive, but with a 400mm lens rather than the scope.

RCC Andromeda Drizzled.jpg

And slightly disappointing Horsehead Nebula using the 150PL and the EQ3-2 using a 45)D - It needs more subs and better framing.

 

Flame and Horsehead_filtered.jpg

And a first light image with the 130P-DS, again on the EQ3-2, only 28 30-second subs, it needs longer for good results:

Veil Binned.png

 

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Is this the best you can do - no absolutely not, you seem keen and the great thing about this hobby is that if you apply yourself you will learn at an exponential rate, in two month's time you will look back and be even more amazed at your progress.

Tracking and stacking - its the only way.  You will be surprised even short subs with 5 or more frames will start to make a huge difference.  

However i note a big difference in your two images with regards to star trails - one is good as i would expect at two seconds the other shows distinct trails so something was different in your process, you could look at what/why.  All that said motor drives on both axis and some autoguiding will take you into another realm altogether.  I can see some cheap motor drive solutions out there so maybe that should be your next investment.  Take advice from others on best option as i have never used :)

Keep at it and look back in some months time and enjoy the improvements.

 

Paddy 

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1 hour ago, PatrickGilliland said:

Is this the best you can do - no absolutely not, you seem keen and the great thing about this hobby is that if you apply yourself you will learn at an exponential rate, in two month's time you will look back and be even more amazed at your progress.

Tracking and stacking - its the only way.  You will be surprised even short subs with 5 or more frames will start to make a huge difference.  

However i note a big difference in your two images with regards to star trails - one is good as i would expect at two seconds the other shows distinct trails so something was different in your process, you could look at what/why.  All that said motor drives on both axis and some autoguiding will take you into another realm altogether.  I can see some cheap motor drive solutions out there so maybe that should be your next investment.  Take advice from others on best option as i have never used :)

Keep at it and look back in some months time and enjoy the improvements.

 

Paddy 

Thanks Paddy, this really is a great hobby, it makes me so happy and fills my mind all the time. You're absolutely right about improving, in the short time I've been doing this I've already seen massive strides forward and learnt so much about processing, still loads more to learn as well. 

With regards the difference in the pictures at the start of the post, the better one is of Polaris, and subsequently has little movement compared to other areas of the sky. I could take longer non tracked subs so it all looks much clearer. It's that picture that is giving me hope that when I have motors, I can achieve similar clarity with other regions of the cosmos 

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On 7/27/2016 at 12:07, billyharris72 said:

 Generally, you can get away with an exposure time of 400 seconds divided by the focal length of your lens or scope in mm. So a 50mm lens will give a 4 second maximum exposure,

I'm a bit confused here, 400/50 = 8

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On 2016-07-26 at 20:41, Marky1973 said:

It might well be, if you have no tracking/guiding going on. Have you seen the No-EQ Challenge thread?

 

I certainly found things improved greatly when I put motors on my old EQ3-2 and then , later, with an NEQ6 and guiding, the sky is literally the limit - now all I need to do is figure out the processing - how hard can that be! :-)

... but usually we knock our heads on the clouds, regardless of setup.

On a more serious note, try to upgrade to a sturdier mount asap. Even with motor upgrade, the eq3 will have difficulties delivering with the scope. I stopped using it with my 150P and only used it with camera and lens in the end. In this configuration it works great as a portable system.

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Out of interest by how much does the RA move with one turn of the flexi thingys ?

Suppose there is no chance that they move the angle by 1/4 degree each turn ?

Just if they did  then one turn per minute would match the earths rotation - the same as when a person builds a barn door tracker and uses a watch to get the rate correct when manually moving it.

Very, very doubtful but thought it worth asking. If anyone has sort of matched I would expect 1 turn = 1 degree.

Ultimately though dual motors will be the way to go, almost no real option.

Terriable thought but making a couple of gears and putting them in a small box to change the rate of turn via the flexi bits sounds like something for a 3D printer project.

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2 hours ago, wimvb said:

... but usually we knock our heads on the clouds, regardless of setup.

On a more serious note, try to upgrade to a sturdier mount asap. Even with motor upgrade, the eq3 will have difficulties delivering with the scope. I stopped using it with my 150P and only used it with camera and lens in the end. In this configuration it works great as a portable system.

IMHO the EQ3 mount gets an unfair press. If cash is short, just upgrade the TRIPOD - see my post earlier for pics taken with a 150PL on an EQ3-2

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