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tooth_dr

The Needle Galaxy with ED80 + CCD LRGB (NGC 4565)

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The beautiful Needle Galaxy, 50 million light years away!

I'm still getting to grips with RGB imaging, and not entirely convinced it's for me yet.

Here is my image of NGC 4565 purely from last night.  I devoted pretty much the entire night to single object, getting up at 12:30am to do a meridian flip and assess focus of RGB filters.

 

LUM = 18000s

RED = 7200s

GREEN = 5400s

BLUE = 6300s

 

Stars look bigger than I would have liked, and the dust isnt as well resolved as I had imagined.

 

Thanks, any comments would be very welcome.

Adam.

 

 

NGC-4565-NEEDLE_GALAXY.jpg

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Another cracking one Adam.....so many we fuzzies in there too.

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Very nice image Adam.

I presume that is 1800s of Lum, not 18000s - otherwise you have really long dark nights in NI. ?

Adrian

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Posted (edited)
54 minutes ago, tooth_dr said:

The beautiful Needle Galaxy, 50 million light years away!

I'm still getting to grips with RGB imaging, and not entirely convinced it's for me yet.

Here is my image of NGC 4565 purely from last night.  I devoted pretty much the entire night to single object, getting up at 12:30am to do a meridian flip and assess focus of RGB filters.

 

LUM = 18000s

RED = 7200s

GREEN = 5400s

BLUE = 6300s

 

Stars look bigger than I would have liked, and the dust isnt as well resolved as I had imagined.

 

Thanks, any comments would be very welcome.

Adam.

 

 

NGC-4565-NEEDLE_GALAXY.jpg

Lovely image Adam. I have about 2.75 hrs of this myself from Thursday night which i still have to process - looking forward to it!

A bit of constructive feedback if i may?

Personally, i would rotate it 180 deg. Maybe it's me being a bit OCD, but i would prefer to see the main bulge on the top side. Otherwise it looks upside-down (to me! lol). 

Not having processed this myself yet, i can't say for certain, but it feels like a lot of the colour has been lost. I think this is due to APP not yet having 'colour-preserving stretching' (it's due soon though apparently). I think you'll find, if you do a PS-only stretch using @sharkmelley 's excellent PS arcsinh-stretching method, and use it just as a colour-layer, on top of an auto DDP stretch from APP (as luminance) then you should hopefully get a lot more colour into the image. 

ps - you can sharpen the dust lane a bit more too if you want. There's loads of signal there, so it can take it. 

Edited by Xiga
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17 minutes ago, Adreneline said:

Very nice image Adam.

I presume that is 1800s of Lum, not 18000s - otherwise you have really long dark nights in NI. ?

Adrian

Thanks Adrian! It’s actually correct! 5 hours of Lum and 5 1/4 hours of colour. Dual rig ?

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Very nice Adam, I took a few subs of it in passing recently but can't image past the meridian here due to S,London light pollution.

Dave

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5 minutes ago, Xiga said:

Lovely image Adam. I have about 2.75 hrs of this myself from Thursday night which i still have to process - looking forward to it!

A bit of constructive feedback if i may?

Personally, i would rotate it 180 deg. Maybe it's me being a bit OCD, but i would prefer to see the main bulge on the top side. Otherwise it looks upside-down (to me! lol). 

Not having processed this myself yet, i can't say for certain, but it feels like a lot of the colour has been lost. I think this is due to APP not yet having 'colour-preserving stretching' (it's due soon though apparently). I think you'll find, if you do a PS-only stretch using @sharkmelley 's excellent PS arcsinh-stretching method, and use it just as a colour-layer, on top of an auto DDP stretch from APP (as luminance) then you should hopefully get a lot more colour into the image. 

ps - you can sharpen the dust lane a bit more too if you want. There's loads of signal there, so it can take it. 

Hi Ciaran,

I always really appreciate it when you take time to provide your feedback, so thank you again ?

I don’t think I really know what I’m at tbh lol

Im using 2x mono cameras so I can’t blame APP for losing colour in this case. It’s probably how I added the lum. Although I did it incrementally.

Red wasn’t focus so good, blue and green were much tighter. I tried to reduce star size in the red channel but I feel like I’m out of my depth. 

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@Xiga I wanted to sharpen the dust lanes but didn’t know how. What would you suggest (if you have time)?

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5 minutes ago, tooth_dr said:

Hi Ciaran,

I always really appreciate it when you take time to provide your feedback, so thank you again ?

I don’t think I really know what I’m at tbh lol

Im using 2x mono cameras so I can’t blame APP for losing colour in this case. It’s probably how I added the lum. Although I did it incrementally.

Red wasn’t focus so good, blue and green were much tighter. I tried to reduce star size in the red channel but I feel like I’m out of my depth. 

Ah, sorry i forgot you are doing LRGB, so it's not due to the APP stretching. 

Looking at it again, it's not actually lacking in colour that much i think. Probably just needs a tad more saturation? Or perhaps, as you say, the Lum may have been added a little too heavy. I can't say for certain, maybe someone else with expertise in LRGB would know? Either way, i think it could take a tad more saturation in places. You already have plenty of yellow in the galaxy, it's just the stars which could do with a bit of a boost. 

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3 minutes ago, Xiga said:

Ah, sorry i forgot you are doing LRGB, so it's not due to the APP stretching. 

Looking at it again, it's not actually lacking in colour that much i think. Probably just needs a tad more saturation? Or perhaps, as you say, the Lum may have been added a little too heavy. I can't say for certain, maybe someone else with expertise in LRGB would know? Either way, i think it could take a tad more saturation in places. You already have plenty of yellow in the galaxy, it's just the stars which could do with a bit of a boost. 

Thanks Ciaran. Looking forward to your version ??

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Posted (edited)
15 minutes ago, tooth_dr said:

@Xiga I wanted to sharpen the dust lanes but didn’t know how. What would you suggest (if you have time)?

Ah, sharpening, that old chestnut! lol. How many ways are there to skin a cat? ? ?

I used to use the PS offerings (smart sharpen or unsharp mask) but i rarely use them now. It depends on the image, but a lot of the time these days i prefer to use Topaz Lab's 'Detail' filter. It lets you target just the Highlights (which is a no-brainer, you never want to sharpen the dark areas) and it also lets you target small, medium, and large scale details separately (similar to the way Registax does for planetary imaging). And if you combine this with a good mask (crucial for most things) then it can be even more useful, as it gives you almost complete control. 

HTH. 

Edit - there are other PS ways too, which i have used in the past, such as duplicating your layer and applying a High Pass Filter to it, then setting the blend mode to either Soft Light or Overlay. But that method requires a deft hand, as you need to set the pixel size of the High Pass Filter very carefully. A very advanced method would involve doing 3 separate ones, with a small, medium and large pixel size. But the Topaz Labs filer is a lot quicker and easier to do! 

Edited by Xiga
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7 minutes ago, Xiga said:

Ah, sharpening, that old chestnut! lol. How many ways are there to skin a cat? ? ?

I used to use the PS offerings (smart sharpen or unsharp mask) but i rarely use them now. It depends on the image, but a lot of the time these days i prefer to use Topaz Lab's 'Detail' filter. It lets you target just the Highlights (which is a no-brainer, you never want to sharpen the dark areas) and it also lets you target small, medium, and large scale details separately (similar to the way Registax does for planetary imaging). And if you combine this with a good mask (crucial for most things) then it can be even more useful, as it gives you almost complete control. 

HTH. 

It does help. I’ll have a look at those Topaz Labs filters ?

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I'm still pretty new to LRGB imaging, but the process I've been using in PI involves extracting the luminance from the RGB image and apply that as a mask, and then applying a very strong saturation boost using the curves tool. Remove the mask and then apply the actual luminance data. Has resulted in some fantastic colour.

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Looks great on detail, i have to agree with Ciarán about the colour. How were the conditions?

Ref sharpening. I use a high pass filter in PS.

I first create a duplicate image then a duplicate layer on the new image, then a layer mask.

Filter/other/high pass filter. Radius set to 27.6 pixels.

Select all, copy. Paste in the mask. Invert the image. Bring up levels and bring the slider up towards the histogram to exclude the stars.

Come out of the mask and change the blend mode to soft light.

Copy and paste the original image over the duplicate and use an eraser set to about 50% or to taste on the areas i want to sharpen.

I hope that makes sense. It can be an extremely powerful filter that brings some great detail to an image. Use sparingly, less is more. 

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19 minutes ago, Allinthehead said:

Looks great on detail, i have to agree with Ciarán about the colour. How were the conditions?

Ref sharpening. I use a high pass filter in PS.

I first create a duplicate image then a duplicate layer on the new image, then a layer mask.

Filter/other/high pass filter. Radius set to 27.6 pixels.

Select all, copy. Paste in the mask. Invert the image. Bring up levels and bring the slider up towards the histogram to exclude the stars.

Come out of the mask and change the blend mode to soft light.

Copy and paste the original image over the duplicate and use an eraser set to about 50% or to taste on the areas i want to sharpen.

I hope that makes sense. It can be an extremely powerful filter that brings some great detail to an image. Use sparingly, less is more. 

Thanks Richard. I’m going to try this. I do use high pass filter but not in this fashion.  This sounds great. 

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2 hours ago, Allinthehead said:

Bring up levels and bring the slider up towards the histogram to exclude the stars.

Hi Richard, I'm struggling with this bit:

Does this look right up to that point?

image.thumb.png.973f2e8ec558db871318ea2ff8c4bec3.png

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Ya that looks right. Although i would move the middle slider to the left as you seem to be masking the galaxy a bit too much.

So now after adjusting the middle slider click on the window to the left of the layer mask and change the blend mode to soft light.

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8 minutes ago, Allinthehead said:

Ya that looks right. Although i would move the middle slider to the left as you seem to be masking the galaxy a bit too much.

So now after adjusting the middle slider click on the window to the left of the layer mask and change the blend mode to soft light.

Thanks Richard again!  I was doing it right but there was no effect on the sharpening.  I repeated with a lower radius and the sharpening is enhanced.  I guess it varies with kit and image quality etc?

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1 minute ago, tooth_dr said:

Thanks Richard again!  I was doing it right but there was no effect on the sharpening.  I repeated with a lower radius and the sharpening is enhanced.  I guess it varies with kit and image quality etc?

No bother at all . It certainly varies depending on kit and target. Widefield nebulae are my usual targets so definitely worth playing around with it. 

I find it darkens dark areas a little too much sometimes so be very selective where you use it. Experiment a little. I always use tools like this on a copy of my image and blend in the parts i like.

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Another stunner from you and as always your processing is something to aspire to! :)

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I think this is a fantastic result for the focal length. I get the feeling it's on the 'colour warm' side, so slightly lacking blue. Then again, it's a bit that way inclined in this part of the sky.

For me sharpening is more about where you do it than how you do it. I'd be embarrassed to tell you the simpleton methods I use...

Olly

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On 01/04/2019 at 21:52, peter shah said:

Oooo that's lovely Adam. Nice natural processing.

Thanks Peter ?

On 01/04/2019 at 23:04, jjosefsen said:

Another stunner from you and as always your processing is something to aspire to! :)

Wow, thanks! i have to say I think your images are just a little step ahead of mine but I think I've found my 'style' of processing.

On 02/04/2019 at 19:26, ollypenrice said:

I think this is a fantastic result for the focal length. I get the feeling it's on the 'colour warm' side, so slightly lacking blue. Then again, it's a bit that way inclined in this part of the sky.

For me sharpening is more about where you do it than how you do it. I'd be embarrassed to tell you the simpleton methods I use...

Olly

Thanks Olly, I've a 10" waiting to go but to be honest I'm like the simplicity of the small short focal length refractor, so am reluctant to swop over.

 

I've tried another go from scratch.  I dont think it's better, just different.  I'm going to leave this one at that, and move onto M101.

Thanks for looking

Adam.

 

 

 

 

LUM-RGB-PROCESSED-SHARPENED-FINAL.jpg

LUM-RGB-PROCESSED-SHARPENED-FINAL-CROP.jpg

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'Thanks Olly, I've a 10" waiting to go but to be honest I'm like the simplicity of the small short focal length refractor, so am reluctant to swop over.'

You and me both! I now do high res in refractors as well.

It takes patience but you can lift an image like yours by having a 'star stretch' and a 'galaxy stretch' as separate layers and combining them. You need to get the background sky identical in both but then you put the star stretch on top and let the faint fuzzies through from the bottom with the eraser.

Olly

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2 minutes ago, ollypenrice said:

It takes patience but you can lift an image like yours by having a 'star stretch' and a 'galaxy stretch' as separate layers and combining them. You need to get the background sky identical in both but then you put the star stretch on top and let the faint fuzzies through from the bottom with the eraser.

Olly

Thanks Olly.  Without wishing to encroach on your valuable time, can I ask, why would I stretch the stars if I spend all my time trying to avoid doing this, making/keeping them small??

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