Chocolate Brownies: LDN 1228 & LBN 552

[mftoet]

I like sweets (ask @ollypenrice), especially chocolate. A lot of chocolate coloured molecular clouds can be found in the wonderful constellation Cepheus. This is the area of LDN 1228 (on the left) and LBN 552. Shown here is the full field of view and a crop that zooms in on LDN 1228 and LBN 552 to show the dark dust clouds in more detail.

Captured during two nights (August 14 and 15) from the dark site of Olly's 'Les Granges' in Étoile-Saint-Cyrice.

Total integration time: 6 hours, 10 minutes (74x 300s subs) | Optics: Takahashi Epsilon-180ED f/2.8 | Camera: Nikon D810a (ISO 400) | Mount: Astro-Physics Mach1 GTO3 guided with a Lacerta MGEN and Vixen 70S guidescope | SQM: 21.4 - 21.5 magnitude/arcsec² 

Data reduction and gradient removal / background correction in AstroPixelProcessor using 30 flats and 200 bias frames. I don't use dark frames but apply (excessive) dithering. Post processing in Adobe Photoshop and PixInsight.

[The Admiral]

18 minutes ago, mftoet said:

A lot of chocolate coloured molecular clouds can be found in the wonderful constellation Cepheus.

Mmm, yummy!

They are nice, almost 3-D to my eye.

Ian

[SkyJamie]

Awesome!

The dust looks great and there is lovely colour in the stars, which are so fine and sharp! Beautiful

[tooth_dr]

Really really nice.  Every time I see you post incredible images, I begin to wonder should I be using my D800E on my 180ed too instead of the CCD.

[MarkAR]

Excellent once again. Loving the thick creamy choccy swirls.

Ps. Flip the first image to see the mushroom better.

[Xiga]

Amazing image. Can't recall ever seeing brown dust look as good as this, and I'm only looking on my phone.

Bravo!

[ollypenrice]

That is simply glorious dust. Lovely to see the denser and more tenuous dusty objects next to each other as well. The three dimensionality of the image is also one of its strong points and the blue stars show that the full colour range has been captured.

Regarding sweets, did you know that The Lounge on SGL has an annual obsession with growing hot chillies? Oh yes!! The perfect antidote to chocolate...

Olly

 

[Tom OD]

You always make the browns look super. Bright, and not dark or dirty and noisy. Amazing detail for 6hrs of exposure. Excellent image,

Tom.

[Allinthehead]

Very tasty Maurice.

[mftoet]

Thank you for your replies.

@tooth_dr: try your D800E on your Epsilon. DSLRs can do a fantastic job with fast optics, especially on a dark site.

@Tom OD (and others mentioning the 3D-look of the browns): no magic was used to enhance the browns. I think the most important step was to carefully correct the background for colour gradients using AstroPixelProcessor's 'Remove Light Pollution' tool. Usually I run several preview iterations (calculations) and keep placing new boxes in the image that look to be 'nebula free' patches of background sky if neccesary. I don't bother about the yellow and red boxes showing up after the calculation. Sometimes I remove them, sometimes I don't. It depends on the result judged by the eye. To make it easier to judge if the colour gradients are properly corrected, I apply a maximum DDP preview stretch during this process. I don't think you can make it perfect with so many dust in the field that differs in brightness, but I find that this tool in APP gives better results than PixInsight's DBE. In the end, I don't process my images for scientific purposes, but to make a picture that's pleasant to the eye.

Another thing that helps giving the browns (or any colour for that matter) a vivid look, is to adjust the saturation slider in APP and/or the vibrance slider in Photoshop's Camera RAW convertor. And then there is 'Match colour' in Photoshop and slight s-curve transformations on the a and b channels in Photoshop's 'Lab colour mode'.

Here's the RAW stack in APP (DDP stretched) to show you what was my starting point.

    

Edited August 19, 2020 by mftoet
typos

[ollypenrice]

6 minutes ago, mftoet said:

Thank you for your replies.

@tooth_dr: try your D800E on your Epsilon. DSLRs can do a fantastic job with fast optics, especially on a dark site.

@Tom OD (and others mentioning the 3D-look of the browns): no magic was used to enhance the browns. I think to most important step was to carefully correct the background for colour gradients using AstroPixelProcessor's 'Remove Light Pollution' tool. Usually I run several preview iterations (calculations) and keep placing new boxes in the image that look to be 'nebula free' patches of background sky if neccesary. I don't bother about the yellow and red box showing up after the calculation. Sometimes I remove them, sometimes I don't. It depends on the result judged by the eye. To make it easier to judge if the colour gradients are properly corrected, I apply a maximum DDP preview stretch during this process. I don't think you can make it perfect with so many dust in the field that differs in brightness, but I find that this tool in APP gives better results than PixInsight's DBE. In the end, I don't process my images for scientific purposes, but to make a picture that's pleasant to the eye.

Another thing that helps giving the browns (or any colour for that matter) a vivid look, is to adjust the saturation slider in APP and/or the vibrance slider in Photoshop's Camera RAW convertor. And then there is 'Match colour' in Photoshop and slight s-curve transformations on the a and b channels in Photoshop's 'Lab colour mode'.

Here's the RAW stack in APP (DDP stretched) to show you what was my starting point.

    

Very helpful.

Olly

[tooth_dr]

@mftoet thanks the reply. That’s exactly how I use APP, it’s great software.

Your stars look pretty good with nothing but the stretch. My imaging resolution is 2.2”/px, and yours is 2.0”/px, so not much difference. Can I ask what method you use for focusing?

 

 

[mftoet]

I use a Bahtinov mask and focus on a bright star while manually adjusting the focuser and look at the spikes at the live display of the camera. 

[tooth_dr]

15 minutes ago, mftoet said:

I use a Bahtinov mask and focus on a bright star while manually adjusting the focuser and look at the spikes at the live display of the camera. 

Thanks Maurice.  Although I have a motorised Moonlite focuser on mine, I also tend to use a Bahtinov mask also, on a magnified image of a star and focus by moving the focuser with SGPro.  Based on your image which has only been stretched in APP, my stars do seem larger to my eye.  I use a Baader UV/IR cut filter which should be of sufficient quality.  Perhaps sky quality plays a part too

[MKHACHFE]

As Alan Partridge would say..

Lovely stuff. 😀