Spongey

An enjoyable galaxy season target despite my limited focal length! I was impressed at the detail resolved in the galaxy at this pixel scale, with star forming regions and clusters clearly visible. This wide field image allows for a wealth of background galaxies to be detected, most of which are hundreds of millions of light years away. I'd highly recommend panning around the image at 100% zoom!

The farthest object I found in this image was a quasar with redshift 3.815, meaning this light was emitted approximately 12 billion years ago, and that this quasar is now over 23.4 billion light years away!

Full details on astrobin.

Cheers

M106 HaLRGB. An awful lot going on in the background with interacting galaxy pairs and large galaxy clusters all over the field. 

There are hundreds of quasars in this image as well, with the furthest having a redshift of 3.815, meaning that this light has been travelling through space for over 12 billion years before hitting my camera sensor   

A classic which I have never shot since getting a proper rig.

Honestly, this image didn't really need the Ha addition, but I had the data, so used it to slightly enhance those regions.

I love the structure and colour variation in the dust under the horsehead, and tried to bring that out during the processing. In particular, the way that hints of blue reflection appear along the bank of dust under the HH is very pleasing.

27hrs 54min HaLRGB. Full acquisition details including Ha mouseover on astrobin: https://www.astrobin.com/fa14ul/

Cheers

My attempt

Colour palette used was the following pixelmath expression, with the crescent itself a more classic hue-adjusted HOO.

// R:
((Ha^~Sii)*Sii + ~(Ha^~Sii)*Ha)*.6 + Ha*.4

// G:
(Oiii^~Sii)*Ha + ~(Oiii^~Ha)*Oiii

// B:
Oiii*.8 + Ha*.2

Workflow was relatively standard:

- DBE each channel

- Remove stars

- Stretch each channel individually with GHS and HT

- Combine channels using the above Pixelmath expression

- Iterative Curves, LHE, and a touch of MLT NR

- Into lightroom for hue and saturation adjustments

- Back into Pixinsight for final adjustments and star-recombination

   - To achieve somewhat normal coloured stars the following Pixelmath expression was used for the extracted stars from each channel. SCNR on both the output of the below and the inverted version was used to remove green and magenta respectively.

// R:
Ha_stars

// G:
Sii_stars

// B:
Oiii_stars

Cheers

On 07/12/2023 at 09:22, Magnum said:

I like it

On 07/12/2023 at 10:06, Mr Spock said:

Lovely image 👍

Thank you both!

First image from the new back garden 😀  We have thankfully had reasonable weather in the south recently, with some good new moon imaging time. Light pollution is slightly worse than from my previous location, but the ease of setup hugely outweighs the negatives.

Navi was a tough one to control in this image, and I'm not entirely happy with the final process, but after four full re-works from scratch I have called it a day.

This is a 25.4hr HaLRGB image, processed using the emissionless technique to accentuate the background dust, with Ha re-added afterwards. There is an awful lot going on in the background in this region, with a nice SNR in the bottom-left corner showing in the Ha master, which looks like a mini-veil nebula. I have searched the SIMBAD database for this in Aladin but can't find anything; if anyone knows the designation of this, please let me know!

Full equipment details and Ha mouseover can be found on my astrobin.

Cheers

After two years of trouble with my scope I finally have it back and working again  

This has been a nice first project to test out the field and colour correction of the scope, but also the depth of exposure I can reach with moderate exposure time from home. I am still ironing out some tilt issues so my corners are not perfect, but with some fine tuning I should be able to achieve near perfection across the field.

There is a huge number of background galaxies in this image. I highly recommend viewing in 100% and panning around to explore.

Nice to be imaging again!

Full acquisition details can be found on my astrobin.

Cheers

Just now, ollypenrice said:

Where would you put the shims?

It depends on your image train. You may be able to add some copper/tin foil layers in between the two halves of a filterwheel or adapters, for example. Bear in mind that at f/2 it will only take a few microns of tilt to throw one corner out of the corrected image plane. 

You could also try using the camera faceplate push/pull tilt adjustment screws, but these can be just as painful as the other method.

Cheers

3 hours ago, ollypenrice said:

Would you experienced users care to comment on this, our worst corner on a 2600 chip wide open and shown here at 100%? The other corners meet the house standard.

Hi Olly,

Given that the aberrations are in one corner only the likely culprit is tilt. Unfortunately with camera lenses there isn't really room for any kind of tilt adjuster but you may be able to shim in-between some spacers to achieve the same effect. Given the optical speed of the system it doesn't take much tilt or backfocus adjustment to send corner stars wonky. If you have AF capabilities I'd highly recommend trying the Hocus Focus plugin in NINA, which will perform aberration inspection throughout a focus run and report on your tilt, curvature, backfocus, etc. You can then make adjustments and re-run the AF routine to compare results and narrow in on perfection. 

For what it's worth I've never seen this lens platesolve to 135mm exactly, everyone I know who has one reports around 130-132mm. 

Cheers

I just got the trial version to see what the fuss is about. I ran it on an image of mine that I captured around this time last year. Here is a snippet of the raw stack after DBE (note this is drizzled data but presented at native res, i.e. 1:2), autostretched:

Here is the stack after DBE and traditional deconvolution vs. the stack after DBE + BlurX in pixinsight, both autostretched.

To my eye the BlurX achieves very similar detail enhancement, but without the additional artefacting/noise generation that traditional deconvolution introduces. I can't see any 'fake' detail, though I'm sure you would get such results if you push the tool too hard. I personally prefer a light touch when processing in general anyway; it's very easy to push things too far with a lot of processes and tools.

I think this is an important comparison to make as it shows the difference from the traditional tools. I can say without a doubt that BlurX is hugely simpler to use compared to traditional deconvolution. The star distortion correction (pushing psfs towards circular) is also very powerful for those with less expensive optics.

I'll be trying it on a few other images but my first impression is certainly positive!

Thank you all again, I really appreciate the support and positive feedback!

8 hours ago, ollypenrice said:

When I read that this was done with a 40mm camera lens I was amazed, because those powdery stars do not look as if they came from a short FL. The image looks telescopic. 

Thank you Olly, your compliments mean a lot to me as your images are some of those that got me into astrophotography in the first place.

The sigma 40mm is a fantastically well corrected lens, and paired with a small pixel mono camera the level of detail attainable from such a short focal length is astounding.

2 hours ago, tomato said:

Have you put it forward for an APOD? IMHO It’s way better than any recent galaxy image selected.

I haven't yet, though I probably will after seeing such a positive response!

I'm glad so many of you have enjoyed the photo. As anyone who does imaging knows, an awful lot of work went into this so it's lovely and very rewarding to have it positively affect so many people!

Thank you all for your kind words!

On 01/07/2022 at 21:22, maw lod qan said:

Setting the camera aside, how would you describe it to the naked eye?

The sky in La Palma is quite special. Though it looks nothing like the image in terms of depth or colour, several of the nebulae are bright and obvious naked eye targets. I found myself laying out under the sky for hours; it's easy to get lost in it all. What I find this image doesn't showcase is how large a field this truly is, the image is 73 x 57 degrees!

33 minutes ago, gorann said:

It could relate to how much Ha is let through in the background sky, and I turned it up quite a bit.

If it is of any use, here is the processed Ha only from the above image:

If you'd like the raw stack to compare with yours, PM me and I can figure out a way to send it to you.

Cheers

54 minutes ago, gorann said:

I was also thinking about this. I did not use DBE but Gradient Xterminator in PS. I decided to leave it as it is since it could be for real especially since I see a lot of structure (dark nebulosity) in the dark area around IC1396. I also found some images suggesting a darker area around the nebula, like this one: https://www.astrobin.com/g59ygw/ and it may be that my strong suppression of the star field (using Star Exterminator) brought out more of the underlying nebulosity and thereby the dark stuff. Also Aladin (DSS2) suggest that there may be a dark area around the nebula (attached image).

Maybe someone knows more and have a comment?

I can't comment on the reality of the dark ring around IC1396 but I can offer another datapoint; my image of this region using the Samyang 135mm and QHY268M (same sensor). There does appear to be a lot of dark dust in this region but I'm not sure the 'dark ring' is that pronounced.

Cheers

4 hours ago, Laurin Dave said:

Amazing stuff Rob...   so many objects to look at so worth zooming in to take a look.  Any chance you can post an annotated version?

Dave

Managed to get a half decent solve after generating a reference starfield and using the ManualImageSolver script! Annotated version included into the OP 

1 hour ago, Laurin Dave said:

Amazing stuff Rob...   so many objects to look at so worth zooming in to take a look.  Any chance you can post an annotated version?

Dave

Thanks Dave,

Unfortunately I'm struggling to get an accurate platesolve on the image, I think because it's such a wide field. Even the Astrometry.net solver drops off in accuracy significantly once you move away from the centre...

http://nova.astrometry.net/annotated_full/6357573 

Any advice would be most welcome! 

This was a two panel commissioning mosaic for the widefield rig I've been setting up while my scope is out for repair, showcasing the vast array of dust across the northern celestial pole. With galaxy season in full swing and a massive FoV like this what else was I supposed to image?

The rig is based around the Sigma Art 40mm and QHY 268M, with images taken at f/2.8.

Total exposure time of 27 hours taken across the clear spell we had at the end of March.

A solved version can be seen below, showing the extent of this field.

Cheers

Edited just now by Spongey

Two panel commissioning mosaic for my Sigma Art 40mm and QHY 268M! 

From Cepheus to Ursa Major, showcasing the vast array of dust across the northern celestial pole.

Total exposure time of 27 hours taken across the clear spell we had at the end of March.

Cheers

Congratulations to all the winners!

I'm sure everyone will agree that having such great data to work with is a real treat, and I am very much looking forward to the next round!

2 hours ago, Xiga said:

Very, very nice indeed! And holds up extremely well when viewed at 100%. 

When you say RGB stars, do you mean you use Ha stars for Lum and then colourise them with the RGB subs, or do you not use the Ha stars at all and just use the RGB stars in full? 

Yes, the luminance for stars is based on the super-lum integrated from the three narrowband channels.

Colour for the stars was brought in with a starmask using the colour calibrated RGB image. I did this using channel extraction / combination in CIE Lab mode.

2 hours ago, Sp@ce_d said:

This is great.. nice processing.. love the palette. Looks great at full res on AB! I take it this is with the APM? Don't see it mentioned on the Tech Card.

Thank you! Yes this is with the APM, missed that one off the tech card but now updated, thanks for spotting it

This is my rendition of the Heart Nebula in SHO, with RGB stars.

This one has been a work in progress for a while, as the weather hasn't been very co-operative. I finally got a couple of new moon clear nights to sink into Sii and Oiii, and this is the result.

The palette is a modified version of that found in this tutorial.

Full details can be found on Astrobin.

CC welcome!

12 minutes ago, irtuk said:

I just took another measurement and its 51mm from the front of the thread to the same position. is this the measurement we think should be 55mm?

 

That's correct, the M62 to M48 adapter that comes with the flattener should be 6mm thick. 

It might be better to try to work out your backfocus using the widths of each component, rather than assuming where the sensor is in the camera. IIRC the ASI1600mm has 6.5mm backfocus, so add whatever spacers you are using and 1/3rd your filter thickness. You want that value to be 55mm the to M48 thread of the flattener adapter. 

20 minutes ago, irtuk said:

Here's a single HA sub, 600 sec, guided

IC1396_LIGHT_2021-10-17_22-40-13_HA_-10.00_600.00s_139_0006.fits 7.82 MB · 0 downloads

it really is just in the corners so I am not that bothered but if its an easy thing to diagnose and fix then why not, I certainly have bigger problems to address

 

I would guess that, based on this sub, your backfocus is incorrect.

The esprit 80 flattener has a backfocus of 55mm from the M48 thread. What does your imaging train look like? You may need to add a spacer or two to get the sensor at 55mm.