Epox75

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

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

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

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

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

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

@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.

@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.

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/

@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

2 hours, more or less, I will see how many frames I have to reject.

Read better

Crescent Nebula.. very starry. 3 hours of integration with Lumicon Deep sky filter. 180x60sec exposures at the lowest settings I've ever tried which is 76 gain / 15 offset. Easy to see how the stars annihilate the sky and nebulosity. And how the brightest stars are overexposed. There were also strong distortion due to the (again) wrong distance from the coma corrector, which I managed to mitigate with masks and deconvolution. Anyway looks like this type of filter is too light for this type of target, I need a narrowband for luminance. Would be also interesting to see what happens with the lowest possible gain settings. After the Crescent 2 nights ago, tonight I had (incredibly) the 5th clear night in a row. I tested the train I created yesterday and guess what? Going even 1 mm farther, compared to the train that so far gave me the best results, increases the distortion so I gotta get closer. I did Iris nebula again 30sec exposures at same gain/offset of the crescent.. just to see how stars behave. Next time (tonight and the next days clouds for sure) I will try minimum gain/offset with longer exposures.

So it turns out that putting a 5 mm extension to the imaging train gives still strong distortion... yet a very different one compared to the distortion pattern i had before, I think that the exact distance is within this 5mm. I got so p..... off by this, that I invented the ultimate imaging train. This one is not only just 1 mm longer compared to the train that so far gave me the best result, but is also extendable for approx 2 mm or even more if I had a longer thread:

I'm on the Crescent at the moment, There might be the chance of clouds here too thou. I'm doing 60 sec exposures (76 gain 15 offset) and i set 240 of them even if I won't be able to do all of them before the sky becomes too bright. I'm quite interested to see the result, this is the lowest I ever went with gain and offset.. and I wonder how the distance from the corrector works. I hope I don't have to buy a new extension. I hate ordering things and paying more of expedition costs than the piece price.... maybe I should add the Baader filter set or another scope in the order This looks sexy to me for instance, I think I understood all the newtonian "features" now and If I got decent stuff out of an umbrella holder, a nice sturdy scope like this (it weights like my c11) with a secondary that is even smaller than the one I have on my 6'' makes me really want to try it out. Moreover that will mean a 6'' at f/4, an 8'' at f/5 and a 11'' at f6.3 or even f/10 for crazy stuff.

Nice! What are your plans? I may try the new imaging train (added a 5 mm extension since getting closer got things worse) on the Crescent Nebula, with lower gain and 60 sec exposures. I also flushed 20 lt of water under my tripod, soil was very hard, this way it should dampen vibrations more. I really don't know what to say about the camera, I have no comparisons to make. I know thou that it has been defined like a sort of breakthrough in AP, expecially for those, like me, living under very light polluted skies.

I know but it's not me.. it's the camera, Jon Rista from cloudynights forum: "You are likely using exposures that are too long. This camera is a very low read noise camera. You don't need exposures that are very long unless you are imaging at a dark site. IF you are imaging at a dark site, and by that I mean a green bortle zone or darker, then you might be able to use 2-minute L subs and 4-5 minute RGB subs. However, if you are near or in the suburbs or the city, even at Gain 0 you will likely find that you can't use L exposures much longer than 30-60 seconds and RGB exposures much longer than 60-120 seconds. I live at a red/white zone border, and a 60-second Gain 0 L exposure is actually WAY overexposed (I get a background sky level of 300e- to 500e-, which is swamping the read noise by 85-150x (and you only really need to swamp it by 20x!))" As for the "optimal" setting. If you truly want to optimize, then you'll need to do some experimentation. You can take increasing exposures for each filter, over many nights, at several different gain settings, to determine, for a given telescope and set of filters, how long you can/should expose to get optimal results. What is truly optimal is going to depend on your seeing, your sky brightness, and your optical system (primarily, your f-ratio and aperture). These will differ for every imager. As a general rule of thumb, you can either aim to swamp the read noise by 20x, or swamp the read noise squared by 3x. So, if your read noise is 1.55e- at unity gain, you would either want to expose until your background sky in a calibrated sub was 31 ADU (20xRN rule) or 7-8 ADU (3xRN^2 rule). Some ASI1600 imagers these days are using something midway between those two, so 15-20 ADU @ Unity Gain, to find a balance of ideal read noise swamping vs. minimal clipping. That said, most ASI1600 imagers are using Gain 0 and/or Gain 76 (Offset 15) for LRGB, Gain 139 (unity) or Gain 200 (Offset 30-50) for NB, and are using exposures ranging from 30s to a few minutes for LRGB, and 90-300s or so for NB." Let's find an agreement, 60 for L (Lumicon Deep Sky or UR/IR Cut Baader), 120 for RGB (Baader CCD) and let's say 180 for NB (have UHC and OIII but are for visual, in the future I will order the Baader set for the Hubble Palette) Tonight I will probably have another go and I would like to ask some opinion: I may either try to tweak again the distance from the corrector and chose another target (Cocoon or Crescent) or keep the actualy imaging train, that still give some distortion, and do the first RGB session for the IRIS nebula. Another possibility is to tweak the imaging train, do more luminance on the Iris Nebula, see if it gets better and maybe also the pictures I've taken yesterday will benefit. Was just thinking of your picture, very nice btw, but how come stars have 2 diffraction spikes? I've never seen that.

Here it is: 347x30sec - Lumicon Deep Sky I can prepare a rar file either with all the lights + calibration frames or I can share the frames already calibrated..

Looks like you are quite north too... UK?

Swan not up here. I listed all the possible targets for me. I am on the Crescent at the moment.... edit: I'm on Iris Nebula again, I didn't like path that the crescent was taking. Too close to a tree in my garden. Got some frame thou, good to see how the lumicon deep sky filter performs on it

Heheh yeah I know I am hard on myself . The secondary mirror wasn't in line with the focuser tube and it had to be moved towards the primary. The best part of my scope is the focuser, the scope tube is aluminum so quite sturdy, then there's a steel base plate and the focuser over it. Moreover i use a four element coma corrector, a quite long solid tube, I believe it even helps making the whole structure of the focuser thicker and less prone to bending. Basically yeah I was sending a very non parallel light to the secondary and consequentially to my coma corrector. I mean I could actually see the offsett of my cell, on one side was completely in on another was coming out of the tube of some millimeter. Yes I do have a laser collimation tool I also have a cap with a hole in the middle and to be honest when I used that I always seen the offset so I tried to adjust the screws of the arms holding my secondary but not seeing much improvement I just scratched my head... until I realized the hard truth I am glad you chance of no clouds! I also have a nice night (3rd in a row) and I am not decided yet. There's the Crescent Nebula, The Cocoon Nebula or the Iris Nebula.. which I used for a distance experiment with the corrector. A very distorted picture and just one hour exposure. What do you think I should try?

Please call me a moron: I had a consistent plane tilt on my Newton and I just realized it now. I mean was I somewhat alarmed by the primary mirror cell not being aligned with the tube when collimated? No! Was I alarmed by the uneven vignetting I could see stretching my pictures? No! Was I alarmed by the reflection of my focuser tube being in my flats? No! I can go on with at least three or four more examples. Conclusions... i am a moron I had to unscrew the secondary mirror main screw for different millimeters before getting it right. And now my thoughts go to the coma corrector, I wonder how much this influenced its efficiency.

When this thing will start, I don't see how it may benefit from a dedicated thread on KSP forum. Email / Skype contact will be more suitable I think, there will be topics to discuss and I believe that a post on a forum, with a delayed reply or easily accessible by anyone not involved, won't help. The amount of information we will have to share with the other members of the project will require a more direct way of communication.

http://www.lightvortexastronomy.com/tutorials.html This is my main reference for Pixinsight, very nice tutorial, every step has a picture and detailed explanation. Also this video made me understand how to use masks, a true breakthrough for me. Now I can apply my beloved deconvolution to the galaxies without touching the stars.

Yes very sure, as a test I applied a luminance of M13 I took with the C11 to the RGB I did with 6'' Imaging Newton.