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Another short break in the clouds allowed me to get some time on a new target for me.

This is only 90 minutes of 180s with the ASI2600mc but I think that for that integration time its not too bad. I was astonished at how much of the blue part of the nebula was standing out considering that this was Monday of this week and so moon was still 90%.

 I only wish only I could get some real time on something to do this camera it justice but I am becoming quite impressed with it.

30 X 180s, SW 80ED, NEQ6, ASI2600mc,

C&C welcome

Flaming-star_final_s.thumb.png.77cf19364f553d8bf3abd31455377ae1.png

Edited by mackiedlm
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22 minutes ago, Crackabarrel said:

Looks great for 90min, imaging time has been precious over Ireland recently

Yes it has been awful alright.

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Hey, 

First off that's a great image! I am currently working on the same target, but at a much lower level of skill!

I am using an unmodded Nikon D800E on an Altair Starwave 102 F7 ED & NEQ6  I have shot two sessions, one with 32 images  @ ISO 800 and 300 sec exposure for a total of 160 minutes and a second session trying ISO 640 with 120 sec exposures.

The results have been fairly disappointing relative to my first target, the Pleiades which obviously is a lot easier, I was able to bring out some nebulosity with nice crisp stars.

On C31 I have attached my stacked image, picking the best 7 NEF files for 35 minutes total exposure, as you can see the nebula is barely there!

For this target do I need to look at a modified or dedicated astrophotography camera? is the filter on the Nikon cutting out the light I actually want to capture ?

Autosave009.tif

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3 hours ago, irtuk said:

Hey, 

First off that's a great image! I am currently working on the same target, but at a much lower level of skill!

I am using an unmodded Nikon D800E on an Altair Starwave 102 F7 ED & NEQ6  I have shot two sessions, one with 32 images  @ ISO 800 and 300 sec exposure for a total of 160 minutes and a second session trying ISO 640 with 120 sec exposures.

The results have been fairly disappointing relative to my first target, the Pleiades which obviously is a lot easier, I was able to bring out some nebulosity with nice crisp stars.

On C31 I have attached my stacked image, picking the best 7 NEF files for 35 minutes total exposure, as you can see the nebula is barely there!

For this target do I need to look at a modified or dedicated astrophotography camera? is the filter on the Nikon cutting out the light I actually want to capture ?

Autosave009.tif 207.54 MB · 5 downloads

Ok, I have downloaded that file and had a quick look at it in Pixinsight.

Unfortunately there is not much I can tell you from that file because it appears that it has not been calibrated at all (no flats, no darks). There is extreme vignetting and a lot of dust bunnies and there appears to be a huge amount of hot pixels which have been streaked bottom left to top right ( I assume no dithering) Also I think your focus is off quite a bit. All this comes together to make it nearly impossible to distinguish the underlying data. I tried cropping and background extraction (gradient removal) but it really did not achieve much.There appears to be some nebulosity showing but its difficult to be sure. Sorry to be so negative. On the plus your stars are quite round even if out of focus.😜

In relation to your camera, this is not the brightest of nebula so you may struggle with an unmodified camera. I dont use Nikon so have no direct experience but I am not one of those who says you'll get NOTHING without a modified camera. Since you have some nebulosity showing (I think) then perhaps with a much longer long integration time (3-4 hours minimum) you may be able to pull something out. But you need to address your underlying issues (focus and calibration - dithering if you are not doing it yet) first.

And dont be too disheartened - I could show you some of my first attempts which would make yours look like a masterpiece.

 

rgds

 

David.

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Thanks for the quick feedback,  

That should have had 7 of each darks, flats and and flat darks in it but I have restacked it so I can try to work out which problems fall in which areas.

in the attached STAR.JPG, the black area in the bottom left, am I right in thinking that's dust on the sensor and the vignette is the curved area around the edge?

there is certainly something going on in the middle that might be the target, but only just!

star.thumb.jpg.cf6bc3b2774a1dbc649e7fe5cab25886.jpg

in the other one, is the lack of focus showing up in the kind of halo around the star?

unfocused.jpg

 

also, not disheartened at all, this is the second or third image I have worked on,  Pleiades I was fairly happy with, beehive cluster I thought was just a bit boring, and then this one.

 

Ed.

 

Edited by irtuk
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Posted (edited)

Hi,

 

Dust - yes. Vignette - kinda! but I'm more talking about the really dark in the corners although the way it turns light further in is part of it - here

vignette.JPG.616e11f650de6be538c4489d33c365f5.JPG

Focus - - not sure how you are getting the bright halo, this is how it looks zoomed in on PI

Capture.JPG.52dcc13c02c2ebaa3a84920a8571e3c5.JPG

But you can see it as fuzzy stars even at less zoom. Above also shows the streaking of red and blue which I think are hot pixels.

 

This is an overlap of your image (left) and mine - (same area, roughly same zoom, same autostretch same point in processing just stacked and autostretch) which gives a better idea of what the OOF looks like. (Up close mines are not perfect either!!)

overlap_stars.JPG.c007e79de77eb04302fba7021a30add9.JPG

 

what you are pointing at is indeed the nebula - the blue reflection part shows well but there is red Ha hiding behind it.

 

HTH, good luck.

Edited by mackiedlm
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On 03/03/2021 at 17:01, mackiedlm said:

Another short break in the clouds allowed me to get some time on a new target for me.

This is only 90 minutes of 180s with the ASI2600mc but I think that for that integration time its not too bad. I was astonished at how much of the blue part of the nebula was standing out considering that this was Monday of this week and so moon was still 90%.

 I only wish only I could get some real time on something to do this camera it justice but I am becoming quite impressed with it.

30 X 180s, SW 80ED, NEQ6, ASI2600mc, 2" L-eNhance

C&C welcome

 

That is a cracking image - 90mins w L-eNhance not even L-eXtreme.  That's v helpful as an L-eNhance example - what Bortle are you in if you don't mind me asking?  

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That's great, thanks. The vignette might be coming with the field flattener. I am re-working the stacking process to try and remove some of the hot pixels.

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Posted (edited)
22 minutes ago, vineyard said:

That is a cracking image - 90mins w L-eNhance not even L-eXtreme.  That's v helpful as an L-eNhance example - what Bortle are you in if you don't mind me asking?  

My apologies - when I first posted that I thought the l-enhance had been in place but when I went to use it some nights later i found it was not. So this was with no filter, and about 90% moon (Night of 1 March). It rather explains why I have so much colour in the stars but now how I managed to get an image at all with the moon so bright. I'm in Bortle 4 but with a dirty great sodium streetlight yards from my set up location.

Apologies again, I have edited the original post.

Edited by mackiedlm
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15 hours ago, mackiedlm said:

My apologies - when I first posted that I thought the l-enhance had been in place but when I went to use it some nights later i found it was not. So this was with no filter, and about 90% moon (Night of 1 March). It rather explains why I have so much colour in the stars but now how I managed to get an image at all with the moon so bright. I'm in Bortle 4 but with a dirty great sodium streetlight yards from my set up location.

Apologies again, I have edited the original post.

No need for apologies! Crikey re no filters w 90% moon & streetlight - what could that camera capture on a new moon night?!

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