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The "No EQ" DSO Challenge!


JGM1971

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From my (extremely) limited use of flats, I seem to remember that it helped if I took half of them, then rotated whatever I was using to diffuse the light (be it tea-towel or anything else) through 90o and then take the other half. That way, any irregularities in the "diffuser" get cancelled out.

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The tube rings arrived,  the mount seems to be up for it, I have set the scope upside down so the camera acts as a tiny bit of counterweight.  

I think I will align with the 150 then swap to the 200 and correct the alignment.  You know it's going to be cloudy this evening though ☺1

20160421_162314.jpg

Nige.

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Unless its the 6" scope, I take flats with the camera and lens/scope at 0, 90, 180 and 270 degrees. I have a patch of diffusely illuminated plain wallpaper that does the job really well.

The big scope seems to give good results from a patch of early morning sky, well away from sun or horizon.

 

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3 hours ago, The Admiral said:

Forgive my ignorance Nigel, are you saying change 'scopes after first aligning? Why do you need to do that?

Is that the 150 on the mount?

 

The mount is overloaded by a few pounds, I am a little concerned about it slewing at high speed so once aligned and on chosen object I will then mount the 200 re aquire the object and shoot away. Well that's the theory.  I will only use the 8" for the fainter objects as the 6" is pretty good anyway. 

One day I might get a Heq5 that will be fine for the 8" not for a while though.

The scope on the mount is the 200p F6

Nige.

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The first stack from my new pc. Taken Saturday 16th April. Old pc would take 3 - 4 hours to stack, new took 45 minutes. 

  M5,  60x20s @1600 iso,  25 dark 50 bias. DSS & StarTools .

PSX_20160425_181728.jpg

I noticed a small faint cloud bottom left, not sure if it's a defect or something else,  will have to check.

Nige.

 

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Looking at the enlarged image without any bright borders around it (i.e. the eye isn't overwhelmed), it looks as though the cluster is surrounded by a broad ring of cloud. I wonder if that is background noise, and the shaddowy spots in it are dust bunnies. It would be interesting to see what effect flats would have.

I have also seen it written that too few darks can introduce noise of their own accord. For what it is worth, I (tediously) take as many dark frames as lights.

Ian

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44 minutes ago, The Admiral said:

Looking at the enlarged image without any bright borders around it (i.e. the eye isn't overwhelmed), it looks as though the cluster is surrounded by a broad ring of cloud. I wonder if that is background noise, and the shaddowy spots in it are dust bunnies. It would be interesting to see what effect flats would have.

I have also seen it written that too few darks can introduce noise of their own accord. For what it is worth, I (tediously) take as many dark frames as lights.

Ian

Thanks Ian 

I have reduced the noise in photo shop express, below image, I hadn't noticed the broad ring although I get it a lot with my 6" scope, I think flats would help a lot with that. It's very obvious in the single frames.

I was experimenting with the darks to see if I needed as many, looks like I need at least 50 with 60 lights.

PSX_20160425_204225.jpg

Nige.

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Excuse the light pollution and the halos (the sky had a very high haze) but here's my first attempt at M57 with the 80ED. I tried to get the 9.25 SCT on it the following night but it was far too windy.

I think this was 31 x 30s lights ISO1600 with flats, darks and bias. 

large.571fbe5d3fef7_2016042502RingNebula.jpg

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On 13 April 2016 at 16:25, The Admiral said:
4 minutes ago, The Admiral said:

Nice capture. It is a small object isn't it, I must have a go myself when it's better placed for me.

Interesting alignment of stars to its right.

Ian

To the right of that are a line of pairs of stars that at first had me worried I'd knocked the mount during the captures

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This is not what I  expected,  only got about 40 usable photos @ 20s , nowhere near enough for the intended target the flame nebula. 40 dark and 50 bias. 

I have over exposed this and lots of contrast to see what I could pull out, there's quite a bit of noise still but it's colourful ☺ I think at least an hours subs are needed.

I'm not sure if there's any nebula in there or just over exposed noise.

PSX_20160428_214832.jpg

Nige.

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Hi Nige, yes that is a very colourful and attractive image. Not sure how you managed it with the weather we've been having.

Having just looked it up :icon_biggrin:, the Flaming Star neb is both an emission nebula and a reflection nebula, and I can make out the 'smoke' of the reflection bit around, is it AE Aurigae, but the red emission neb I'm afraid I can't see, apart from a tiny smidgeon above the star to the right of AE Aurigae. Looking at pictures of the nebula this corresponds with a bright bit of the emission. I presume this is with the 200p, but even so it looks as though you're going to need more subs, and of course it is quite low. Not sure about the rest of it, but my money would be on noise.

I can also see stacking artefacts along the RHS and also along the bottom. If you cropped those out then 'wipe' might leave a cleaner background I suppose, but as always, more photons is going to be your answer! If that's with the 200p, I'm not sure how I'd get on with a 100mm refractor.

Ian

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3 minutes ago, The Admiral said:

Hi Nige, yes that is a very colourful and attractive image. Not sure how you managed it with the weather we've been having.

Having just looked it up :icon_biggrin:, the Flaming Star neb is both an emission nebula and a reflection nebula, and I can make out the 'smoke' of the reflection bit around, is it AE Aurigae, but the red emission neb I'm afraid I can't see, apart from a tiny smidgeon above the star to the right of AE Aurigae. Looking at pictures of the nebula this corresponds with a bright bit of the emission. I presume this is with the 200p, but even so it looks as though you're going to need more subs, and of course it is quite low. Not sure about the rest of it, but my money would be on noise.

I can also see stacking artefacts along the RHS and also along the bottom. If you cropped those out then 'wipe' might leave a cleaner background I suppose, but as always, more photons is going to be your answer! If that's with the 200p, I'm not sure how I'd get on with a 100mm refractor.

Ian

This was taken Saturday 2 weeks ago with the 150p,  getting as many subs as poss before it dipped behind  neighbours roof. Not had the scopes out since then ?

Cloudy weather and a bad cold have stopped all attempts. Which is the reason behind me playing with this image, to try and squeeze something from it. I  sort of new there was not much hope as I was taking the shots, normally I would see some faint cloud in an image while taking the subs but with this I saw nothing, but I have been having fun with startools. 

Nige.

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It's hard to tell but you may just have a tad of the blue in the Flame, I see no red.

Not the same scale as yours but here is one I did at 200mm with a Canon 7DMK2.
This was 26x2minutes with a Canon 70-200mm L IS II lense.
There is blue in the Flame portion that I found hard to bring out.
The 7DMK II is unmodded so allows the orangey/brown dust to show as well.

flameccpiccsncrfinaldarker.jpg

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2 minutes ago, The Admiral said:

That's a nice wide-field image Mike. I hadn't realised that there was so much dust around.

Ian

I did a widerfield at 100mm and the whole area is crazy with dust, right through the
Messiers 36/38 as well.

Nigel may have captured some of it but it's hard to say, it needs closely comparing
to a deeper image.

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7 hours ago, wxsatuser said:

It's hard to tell but you may just have a tad of the blue in the Flame, I see no red.

Not the same scale as yours but here is one I did at 200mm with a Canon 7DMK2.
This was 26x2minutes with a Canon 70-200mm L IS II lense.
There is blue in the Flame portion that I found hard to bring out.
The 7DMK II is unmodded so allows the orangey/brown dust to show as well.

flameccpiccsncrfinaldarker.jpg

Thanks for showing this image Mike, it gives me an idea what's there ☺, I guessed I would need at least an hours subs for this.

Nige

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Had an unsuccessful night where my focus went as the temperature fell. Only my first 10 subs of M13 seemed to gives results. 

10 x 45s ISO1600 lights with flats, darks and bias applied. Processed with levels and curves in Photoshop with final touches in Lightroom Mobile.

Taken with the Esprit 80 on the Evo mount with the Canon 60D.large.image.jpeg

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It's still turned out pretty good though.

Can I ask an unrelated question? How good do you find the tracking of the Evo mount when used with the long focal length 9.25" ? Is it stable enough to do astrophotography on small objects do you think?

Ian

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I also had to re focus last night, not sure what caused it, luckily only about 10 frames were lost before I noticed. 

I did however use flats with great result, much better images to work with. As my pc is only about 10 ft away from the scope, I pointed the scope at a white screen and shot away.

I'm pleased with the result using flats but still room for improvement. 

First the Owl nebula and neighbouring galaxy 80 x 30s at 1600 iso, 50 dark, 20 flat, 50 bias. Scope 150p. 

Second, Black eye galaxy 90 x 30s plus the above.  I am currently stacking the Ring nebula 54 frames.

Nige.

PSX_20160430_144719.jpg

PSX_20160430_145143.jpg

 

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22 minutes ago, The Admiral said:

It's still turned out pretty good though.

Can I ask an unrelated question? How good do you find the tracking of the Evo mount when used with the long focal length 9.25" ? Is it stable enough to do astrophotography on small objects do you think?

Ian

I've been able to get 15 to 20 second subs but it's 50/50 at that point. It's very sensitive to the slightest breeze. But it's great for planets and visual. 

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