The Astro-Imaging Thread

[kurja]

3 hours ago, FokkerAce said:

nope, no telescope in that picture, I have a Celestron astromaster 70mm refractor 

900 mm long tube? So if you have a 3mm ocular, that's already 300x magnification. Add a 2x barlow and it's 600x, when the twice-your-aperture rule of thumb suggests to stay below ~140x for ideal image quality. No wonder if your view seems blurry.

Edit; you had a diagonal mirror between your barlow lens and ocular? You might try if it's any better without the mirror.

Edited June 22, 2017 by kurja

[Epox75]

11 hours ago, Green Baron said:

@Epox75: it seems that there is less noise and the filaments are clearer than in the 30sec exposures, what do you think ? Now with 2min exposures the nebula might even be clearer. Yeah, stars are overexposed. There is nothing one can do i think ...

 

There was an open sky this morning, i saw the galaxy high in the sky. The next two days we'll have a phenomenon called Calima, that means high moisture and a lot of desert dust in the lower atmosphere. Thereafter we'll see :-)

@Green Baron The only comparison I can make is with Elephant Trunk where I used 30 sec exposures at 139 gain / 21 offset. While I totally agree with the less noise, that picture I took was way out of focus but anyway yes, the details seem good also at this settings. Next time I want to try one and two minutes exposures with minimun settings (0 gain 10 offset) and see what happens. I also intend to figure out guiding better, I've been lazy so far by always using the st4 port on my camera and attached to the mount, while I should use the Celestron drivers so I can interface the mount to SGPro, configuring PEC, backlash, plate solving and so on. 

We have a similar wind in Italy (did I say already I am from Rome? I lived there 27 years) we call it Scirocco.... everything turns red  

[Green Baron]

Rome, the eternal city ! Cheers from La Palma, a greean island in the atlantic ocean.

Gain and offset don't tell me nothing. My camera doesn't have these settings. It can only take pictures at a given temperature for a given exposure time. I assume they are settings for the signal amplifier/processor to do something ? Like ISO settings on a dslr ? What i know from dslr photography is that a chip has its highest dynamic range (in terms of light values, lv) when the signal is unamplified. That means for a dslr, if a chip is designed with an iso of 200, it will have the best performance at iso 200. Every higher setting will make things worse, like the noise is equally amplified with the signal.

Good luck !

[RoadRunnerAerospace]

14 hours ago, kurja said:

900 mm long tube? So if you have a 3mm ocular, that's already 300x magnification. Add a 2x barlow and it's 600x, when the twice-your-aperture rule of thumb suggests to stay below ~140x for ideal image quality. No wonder if your view seems blurry.

Edit; you had a diagonal mirror between your barlow lens and ocular? You might try if it's any better without the mirror.

there is a diagonal mirror between the tube and the eyepiece

[Epox75]

4 hours ago, Green Baron said:

Gain and offset don't tell me nothing. My camera doesn't have these settings. It can only take pictures at a given temperature for a given exposure time. I assume they are settings for the signal amplifier/processor to do something ? Like ISO settings on a dslr ? What i know from dslr photography is that a chip has its highest dynamic range (in terms of light values, lv) when the signal is unamplified. That means for a dslr, if a chip is designed with an iso of 200, it will have the best performance at iso 200. Every higher setting will make things worse, like the noise is equally amplified with the signal.

Good luck !

Yes Gain/offset can be compared to the ISO of DSLR even if I have to admit I am bit ignorant (let's say very ignorant) about the technical details. Trial and error for the win!  What I read about the AI1600MM-Cool is that even at highest settings keeps the noise acceptable and there are also settings that give extremely low noise (like the 76/15 or the 0/10). 

I finally integrated the data from 4 days ago to the Fireworks Galaxy. 11.2 Hours - 5.2 for Luminance, 6 for RGB. Luminance is a combination of the Lumicon Deepsky filter and the UV/IR Cut Baader. 

Edit: can you spot that wierd object almost at the right center side of the picture? It's looks like something enveloped by a ball of nebulosity anyway is not an artifact because it appears like this in all the pictures and I cannot find anything about it. 

Technical card: 

http://www.astrobin.com/299244/J/

Edited June 23, 2017 by Epox75

[RoadRunnerAerospace]

I was getting some star fields a little bit ago, and a super bright meteor flew over, like magnitude 0 to around -1 scared the ever living crap out of me when i first noticed it....

Edited June 23, 2017 by FokkerAce

[Adstri]

Are there any objections against the Lagoon Nebula?

[RoadRunnerAerospace]

7 minutes ago, Adstriduum said:

Are there any objections against the Lagoon Nebula?

not really

[Epox75]

@Green Baron I have a question to ask if you don't mind. You seem to know your newtonians so I would like to hear from you before moving the CN community  

How does this look? scope is collimated in this picture but i'm more interested in knowing if the secondary is in a right position. Yellow circle is the hole on my cap centered in the primary donut, the red circle is the back of my cap, so the focuser hole and the green one is the secondary as I see it (circle might not be perfectly correct because of the light). For info: I cannot move the secondary further back, it basically at its max. 

Edited June 24, 2017 by Epox75

[Green Baron]

I feel honoured :-) I probably have my knowledge from the same sites as you. Example (not regarding offset) Or this. Newtons can be demanding, another reason why i got me an apo :-)

A assume that your eyepiece is centered in the drawtube and the drawtube of the fcuser is rectangular to the optical axis. Then this looks to me as if the secondary is not quite centered towards the drawtube. If this is because of the offset then it might be okay, but afaik the offset goes towards the focuser and the main, not away from the focuser. Also i see the focuser tube getiing in the way, which might lead to partial vignetting. Maybe you can find a setup where it is as far out as possible ?

But by all means please do ask on CN and let us know the opinions of the savants there :-) !

 

[Epox75]

@Green Baron Thank you! This makes things a bit clearer now. Don't worry about the focuser, it goes completely off the tube after focusing   Anyway if I understood correctly you mean this right? where red is wrong offset direction and green correct? If i am correct how do I rotate the secondary that way...  by loosing the collimation screws and moving the center one?

A little update with a more clear picture: collimation went off a bit because I was moving screws around. I think cap and draw tube are in line, and my line of sight goes straight into it (rail is my reference). The problem is that I cannot create an offset that goes on the opposite side because i can't move the secondary further back  So i'm wondering If i should drill four more holes for the spider arms 1 or 2 cm closer to the aperture. 

 

 

Edited June 24, 2017 by Epox75

[Epox75]

I opened a thread on CN. In case you wanna follow it: https://www.cloudynights.com/topic/581915-fast-newton-secondary-offset-looking-for-feedbacks/#entry7957875

[Epox75]

I brought the Fireworks Galaxy up to 14.1 hours of integration. I reprocessed the image in a different way: I followed the written tutorial I posted some day ago until the calibration of the exposures then I went alone with what I've learnt about image stacking and processing. A single reference frame from luminance was used to register all the exposures (color included), I used distortion correction on the exposures alignment phase (I spent the whole day yesterday using different parameters for distortion correction and then weighting the quality of the exposures with Deep Sky Stacker to evaluate changes in score and see which was the most performing setting). 

After the image stacking I did the background extraction on Luminance and Color, combined the channels and did color balance with background reference.  After that I stretched the midtones of the image until the star clipping limit and I stopped. I created a Star Mask, inverted it and applied it to the image to protect the stars from further processing and then I kept stretching the image with all but the stars being affected. I found the result very interesting especially for star size and RGB background noise, it was extremely less evident. 

The few noise that was visible on the image was annihilated using an inverted luminance mask to protect stars and galaxy while doing so. 

After that I applied a range selection mask to protect everything but the galaxy, boosted its saturation and applied a deconvolution with deringing to enhance the details of the galaxy, especially the core... and that's it. Sorry for the long post, but I'm very happy.. this is the 1st time since I started this type of imaging that I go alone with my ideas, here's the result:

Updated technical card on Astrobin:

http://www.astrobin.com/299244/K/?nc=user

 

 

[kurja]

23 hours ago, Epox75 said:

 here's the result:

Updated technical card on Astrobin:

http://www.astrobin.com/299244/K/?nc=user

 

 

I always have fun looking for objects I didn't know about in deep images, there's a bunch in this one. Did you happen to run a plate solver?

Color saturation is a little much for my taste.

[Epox75]

2 hours ago, kurja said:

I always have fun looking for objects I didn't know about in deep images, there's a bunch in this one. Did you happen to run a plate solver?

Color saturation is a little much for my taste.

Yes I did plate solve the image and I couldn't find anything on those 3.. .if we mean the same ones. I tried on astrometry.net and I get this:

I was thinking about trying unimap for the 1st time and see what comes out. About saturation.. yeah I know I might have exaggerated a bit, yet NGC 6946 it's a very colorful galaxy and saturation enhances it's halo which I like a lot. Anyway I plan to integrate more hours so there will be plenty of different versions before the final one. I'm still figuring out a proper workflow and until then.... experimentation!

If I figure out unimap, I will post its results soon. 

Edit: I can't figure it out at the moment. I cropped the image on the most interesting object I sent it to astrometry... it's kind of going crazy and it won't stop analizying the image.

Edit 2: Cropped plate solving failed so I posted a picture on Astrobin asking for help for identification, we will what comes out 

 

 

Edited June 26, 2017 by Epox75

[Green Baron]

Looking at the stars, i find the colour ok ...

[Epox75]

4 minutes ago, Green Baron said:

Looking at the stars, i find the colour ok ...

That's because I did a masked saturation only on the galaxy

[Epox75]

Found one! Thanks to a user on Astrobin: http://simbad.u-strasbg.fr/simbad/sim-id?Ident=%407846909&Name=2MASX J20324060%2b6000181&submit=submit

[kurja]

7 hours ago, Epox75 said:

Yes I did plate solve the image and I couldn't find anything on those 3.. .if we mean the same ones. I tried on astrometry.net and I get this:

Plate solving in PI has parameters, it's been a while since I used it, but it can label the smallest, tiniest galaxies... You have to choose which catalogues to use I think. Even just looking on my phone, I can already see many faint galaxies in your picture.

Edit, try pgc (principal galaxy catalogue), messier and ngc contain only the most obvious galaxies - why we hobbyists use those catalogues ,) - but to label the smallest faintest things, pgc is better.

Edited June 27, 2017 by kurja

[Epox75]

15 hours ago, kurja said:

Plate solving in PI has parameters, it's been a while since I used it, but it can label the smallest, tiniest galaxies... You have to choose which catalogues to use I think. Even just looking on my phone, I can already see many faint galaxies in your picture.

Edit, try pgc (principal galaxy catalogue), messier and ngc contain only the most obvious galaxies - why we hobbyists use those catalogues ,) - but to label the smallest faintest things, pgc is better.

I tried plate solving with PI and then image annotation script. No matter what parameters or catalog I use I always get the same result when annotating, maybe I'm missing something. None of the galaxies that I saw on the cropped picture have been labeled... and unimap crashes on me... sigh

 

Edited June 27, 2017 by Epox75

[_Augustus_]

Edited June 28, 2017 by _Augustus_

[Epox75]

Another update on image annotation. Looks like that galaxy is in the 2MASS catalog which can be queried, downloaded and interfaced to Pixinsight. It seems difficult but in truth is extremely difficult, at least for me.. the deep space newbie :P. 

Anyway here's the reference: https://pixinsight.com/forum/index.php?topic=3966.75 (6th post from top)

[_Augustus_]

[Adstri]

All of this deep sky stuff and not a lot of planets...

BEHOLD URANUS:

This wasn't processed very nicely

From top to bottom: Oberon, Titania,, Miranda, Uranus, Ariel, Umbriel.

Super happy how this turned out!  Next stop: Neptune!

[_Augustus_]

1 minute ago, Adstriduum said:

All of this deep sky stuff and not a lot of planets...

BEHOLD URANUS:

This wasn't processed very nicely

From top to bottom: Oberon, Titania,, Miranda, Uranus, Ariel, Umbriel.

Super happy how this turned out!  Next stop: Neptune!

YOU GOT THE MOONS!

Explain.