M42 High Detail - First attempt!

[Flea77]

Since this experiment was all about improving, lets start with my last attempt at this target.....

The next image is my new attempt, trying to capture as much detail as possible....

I should first point out that this was done on a horrible night, skirting clouds, nice layer of haze over everything, but since it was the first night in three weeks where you could actually see any stars at all, I went for it.

I would be very interested in your opinions, good and bad. Preferably the bad so I can use that information to improve some more. Here is what I think about it....

The level of detail for a DSLR shooting RGB is impressive. You certainly could do better with narrowband and a cooled CCD but for what I have to work with, not too shabby. I am not sure I like the core. I like the colors better, and most of the stars are OK, although I think the different regions may be a little to harsh (the only sharpening was done for screen output in Lightroom, very minimal).

Now the details.....

All ISO 800:

5second x10 lights + 20 darks +20 bias

10second x10 lights + 20 darks +20 bias

15second x10 lights + 20 darks +20 bias

30second x10 lights + 20 darks +20 bias

45second x10 lights + 20 darks +20 bias

60second x10 lights + 20 darks +20 bias

90second x10 lights + 20 darks +20 bias

120second x10 lights + 20 darks +20 bias

180second x10 lights + 20 darks +20 bias

Each set was stacked by itsself in DSS, applied +15% saturation, then imported into Lightroom 3.6. The whole set was then HDRed in HDR Efx using a 1ev spread, then cropped and saturation boosted in Lightroom. Final adjustments in Photoshop CS5 (levels slightly stretched, green removal, etc). Lastly exported from Lightoom with mild screen sharpening and resized from the cropped 3101x2481 to 1024x819.

Tell me what you honestly think!

Allan

[johnh]

Thats a great result and good exposure info, darks are essential as you've shown. Fantastic detail in the core and outer gas very strong. Many parts are too black while bottom right corner is just right as blacks are killing the faint gas. Brighter stars are bloated. This is a great effort though for a DSLR with the fine faint detail at the bottom of the image.

Old attempt is completely out done by the new effort, what scope did you use?

John.

[Flea77]

John,

Thanks for your comments. I used the 110 in my sig. The blackness was a choice, I could either go with a lighter background and show more fain gas or go for higher contrast and lose a little of the faint stuff, I chose the latter.

You mention star bloat, is there any way to prevent that short of narrowband?

Allan

[Shibby]

Alan, you've done really well there, all those different exposure lengths have resulted in one of the best controlled cores that I've ever seen!

As John says, there is some clipping of the histogram in parts of the image - particularly in the red channel. This is probably due to lack of flats (you could use a gradient removal tool here to help).

I don't think the star bloat is that bad considering the scale of the image, but I use a star layer mask when processing my images so that's something you could try.

[Keiran]

Thats a very nice image, is this cropped at all? Thats a huge improvement on the first image. Congrats

[Flea77]

Thanks all for the comments, keep them coming!

Lewis, can you point me to some resources for the star layer map?

Keiran, Yes, it is cropped from a 4991x3280 to a 3101x2481 image.

Allan

[Sam]

That's a huge improvement on the first one - lots and lots of detail and plenty of wispy nebula and filaments visible - very nice!

[Shibby]

Lewis, can you point me to some resources for the star layer map?

Certainly! http://stargazerslounge.com/imaging-tips-tricks-techniques/47063-5-creating-star-layer.html

[RogerTheDodger]

Hot damn that's lovely... the first image of it where I get an impression of depth, well done indeed

[ollypenrice]

Well first off it's darned good, full stop. Lots of detail over the huge dynamic range.

You asked for hard critiques so I feel this;

The core is detailed but has a 'look' that I associate with HDR wavelets in PI and about which I have mixed feelings. I prefer to get the dynamic range following Jerry Lodigruss;

Compositing 2 Different Exposures via Layer Masks and then I use Unsharp Mask selectively on the strong core signal. However, on going back to yours I have to say it's growing on me!

You can debloat stars like this, maybe going into the blue channel for a second dose if blue is defeating your lens/camera and flaring.

Compositing 2 Different Exposures via Layer Masks

There is a hidden circular marquee around the target star, well feathered. The lowest point on the curve was placed by putting the cursor near the star around the background and Alt Clicking.

I wonder if you could get more stqr colour, always a DSLR issue. The shorter subs often have the best star colour so maybe you could put them under the final image in Ps, massively boost the saturation, and gently erase the white stellar cores. I did this on mine and do it also to restore natural star colour after Ha addition.

Congratulations on a big hit.

Olly

[Peter Reader]

Great image! Why did you use some very short exposures?

[Flea77]

Lewis, thanks, I will look into that!

Roger, thanks!

Olly, thanks for the links, I will check those out this weekend when I get some time.

Peter, the short exposures provide the detail in the core while the long exposures provide the fainter nebula on the outer edges. If you just take long exposures the core (central region) blows out (goes completely white). You have to combine different exposures to get everthing correctly exposed.

Allan

[Flea77]

Olly,

Evidently I can not make the composting work right, following the directions in the links you provided results in the following comparisons (composting on the left, HDR Efx on the right):

I'll keep working on it but so far it doesn't seem to be working for me (of course that may be I am comfortable with HDR Efx and not with this composting technique too).

Suggestions or pointers welcome.

Allan

[JohnC64]

>>"Tell me what you honestly think!"

Wow - Brilliant!!! Thats such a fabulous image. Definitly trying this technique next year.

Cheers John

[Peter Reader]

Thanks for the advice!

[Flea77]

OK, take two!

Here I calmed the central core down a bit, added a little more nebulocity to the red portion and added a little more dust while maintaining the overall look. Better? Worse?

Allan

[nmoushon]

WOW! That's a big improvement! Not that it was bad to begin with just really like how much more you added to it. What you did to enhance the nebulosity worked really good! The colors look much deeper and richer! I love the finer detail you can see in the arms and the faint detail in the clouds. I wonder how the running man would look with this style of processing and exposure times? Again well done!

[ollypenrice]

Hmmm, a bit 'waveletty' to my eye but please ignore me! I think the trick with Lodigruss is to get the short exposure looking right before you layer mask it. I entirely agree that your own method worked better for you so sling my idea into the bin and carry on!!

I've been working on M42 for four years. It's a life sentence but a nice one...

Best,

Olly

[Flea77]

Olly,

I have no intention of slinging any idea into the waste basket, it gives me something to work on to add another tool to my toolkit. While it obviously is not working for me right now it does give me another approach to explore which even if it does not work out for this target might come in handy later.

Any way it goes I very much appreciate the comments and information you provided.

Allan