2nd light - M42 the Orion Nebula.

[Alveprinsen]

My first picture of M42, fresh out of the European Extremely Average Telescope - 30 minutes ago.

Light frames: 45 x 2 minutes.

Dark frames: 25 x 2 minutes.

Bias frames: 25

Total exposure time: 1h 30 minutes.

ISO setting: 1600

Camera: Nikon D3100 unmodded.

Tracking: Yes.

Even though the moon was pretty damn bright, I thought I'd give it a shot anyways, considering how we havent had clear skies here for quite some time.

I've allways wanted to photograph M42, but never had the chance... until now.

I used high iso and short total exposure time since this wasnt going to be any serious data collection anyways. As soon as the moon goes away, I will smack in a 2x barlow and make the nebula fill the entire chip, and take pictures on ISO 400 or 800 instead to avoid unneccesary noise.

Anyhow, for a first try, I am quite happy with this. Perhaps I could have perfected focus just a tad more though... Oh well, next time.

Good night and good morning!

Sincerely, Alveprinsen.

[ilove1995]

I think that looks awesome. Referring to tracking were you set up for auto guiding when you took those subs? Would you mind confirming what mount and guide camera you used?

Al

[Zuben Elgenubi]

That's very nice 

[stevetynant]

Beautiful - well done

[K3ny0n]

Love it. 

Rob

[Dave Wall]

Very nice.

[Matt Scunthorpe]

Brilliant photo. I am looking forward to having a go at this again when it gets higher a bit earlier.

Do you always used ISO1600? I was always told (for Canon at least) not to go above 800. Might have to have a play around.

Matt.

[wookie1965]

Thats a cracking picture i would have that as desktop wallpaper.

[Alveprinsen]

I think that looks awesome. Referring to tracking were you set up for auto guiding when you took those subs? Would you mind confirming what mount and guide camera you used?

Al

Hello. I was using a Orion StarShoot Autoguider hooked up to a 102/500 Skywatcher Starwalker refractor.

[Alveprinsen]

Brilliant photo. I am looking forward to having a go at this again when it gets higher a bit earlier.

Do you always used ISO1600? I was always told (for Canon at least) not to go above 800. Might have to have a play around.

Matt.

I've been using ISO 1600 simply because I've been "in a hurry". As you can see, it creates quite some noise. I plan on doing ISO800 next time. This picture is just a test.

[Alveprinsen]

Oh, btw... the core seems to get rather overexposed...

Could someone telle me how this business of combining several images into one goes?

Would you take many long exposures, and several shorter exposures, and stack'em all together in deepskystacker, OR, would you simply stack an entire picture of M42 with overexposed core and everything, then stack a lower exposure, then simply just overlay and edit the two it in photoshop or lightroom or whatnot?

Or is there some kind of tecnique people apply to make this happen during the stacking proccess itself?

I keep reading ppl. saying one should get some longer exposures for this, and shorter exposures for that...

Alveprinsen.

[Astro Imp]

Well done, looks like the European Extremely Average Telescope is doing it's stuff.

I look forward to seeing more of your work.

[Uranium235]

A good start, but maybe you should try processing this by merging two separate stretches of the image - one short, one long. That way you can develop the outer nebulosity without blowing the core, full instructions can be found here:

http://www.astropix.com/HTML/J_DIGIT/LAYMASK.HTM

Its a method you can apply to any target with a high dynamic range.

This target has a lot to offer the DSLR, give it more (and longer, preferably 10min) exposures. Once you get up to 6 hours worth, it starts getting a bit special

But one word of warning, the more you expose this one to chase the outer fluff, the more layer masks you will need (my 2012 version took 5 masks!).

[Alveprinsen]

A good start, but maybe you should try processing this by merging two separate stretches of the image - one short, one long. That way you can develop the outer nebulosity without blowing the core, full instructions can be found here:

http://www.astropix.com/HTML/J_DIGIT/LAYMASK.HTM

Its a method you can apply to any target with a high dynamic range.

This target has a lot to offer the DSLR, give it more (and longer, preferably 10min) exposures. Once you get up to 6 hours worth, it starts getting a bit special

But one word of warning, the more you expose this one to chase the outer fluff, the more layer masks you will need (my 2012 version took 5 masks!).

Say no more! I just finished a test using the tutorial you posted:

I am looking forward to doing some longer exposures of this one... But for now, I need to finish M31. Once that is done, I will do M42. I have to use a 2x barlow on my 600mm in order to fill the chip with the nebula, and I dont want to start messing around with my current setup just yet. M31 first, then this one. But now at least I know the tecnique!

Oh, I guess I need to use this tecnique for M31 as well? The core IS kinda bright....

Sincerely, Alveprinsen.

[Amra]

Nice images! Can't wait to image this one again, my first & only image with my reflector was back in march and it was a bit out of focus, but all the Ha was there in even just a 10s exposure, crazy!

But say, wouldn't it be better to not use a barlow as it increases the exposure times and instead just crop the image? DSLR take quite high resolution images after all.

[Uranium235]

There ya go! Just like magic!

Once you start getting the longer exposures you can start pushing for more Ha, because M42 sits in a sea of the stuff (you would be shocked at how much is there). And yes, you will probably also need to apply the layer mask technique to your M31 project, becuase thats another one with a high dynamic range.

However, I would advise against using any barlows when imaging DSO targets. A 2x barlow will quadruple your imaging time, introduce coma and all manner of nastiness - best avoided (been there, done that, got the t-shirt!).

[Alveprinsen]

However, I would advise against using any barlows when imaging DSO targets. A 2x barlow will quadruple your imaging time, introduce coma and all manner of nastiness - best avoided (been there, done that, got the t-shirt!).

Hmm, but I want to make full use of the huge DSLR chip size!

Ok, so how about I slap a 2x reducer on my Skywatcher Skymax 180Pro? Its a 180/2700mm Maksutov. I could cut that in half making it a 180/1350 with a reducer, no? I dont know if that would mess up the picture too much? I am here of course referring to the corners of the image.

Sincerely, Alveprinsen.

[Alveprinsen]

Ok, so how about I slap a 2x reducer on my Skywatcher Skymax 180Pro?

Scratch that.. I ment a 0,5x reducer.

Alveprinsen.

[Uranium235]

It depends on the reducer, if its a cheap 0.5x reducer the results wont be great (only a small area of the field will be useable). But if its a reducer that is specifically for Maks (even better if matched), then it stands a chance of yielding decent results. Best advice I can offer is to stick with the 80ED and just keep hammering away at whatever you choose to image, you have the matched reducer for it? As that will help a lot with field correction and speed. I decided a while ago that the only way forward with DSLRs is weight of numbers, long(ish) subs... and lots of them!

Also, your camera type (Nikon), is unknown territory for me when it comes to long exposures. Hopefully you wont suffer amp glow once you get to 10min+

[Alveprinsen]

I managed to get 1h 30 minutes of 10min exposures at ISO800.

Now the damn clouds have been pestering me for the past few days.

The other day I went down to the observatory... Clear skies.. Not a cloud, not even in the horizon. I ended up deleting 18 out of 20 10 min exposures... Why? Clouds crept up on me as soon as I turned my back. Manifested out of absolutely nothing.

Tonight I was on my way down, but I just turned around... clear skies in my telescope blind-zone... of course... and clouds (possibly of sulfur) straight from hell between the scope and M42. :/

[Alveprinsen]

Does the picture look out of focus? I swear I had perfect focus.. Used my bahtinov mask and everything... :/

[Uranium235]

Looks in focus to me!

There is more data in there to be had, but it needs more stretching to get it out - possibly using 3 different versions (short stretch, medium stretch, long stretch) for layer masks. First, merge the two shorter versions, then merge that one with the long stretch version.

[Alveprinsen]

Hmm, could someone help me out with this "stretching" thingy, whatever that is... I assume it concerns stretching the "levels" in Photoshop or whatnot to bring out details?

Also, this layering... my first attempt with two layers looks fine... but... I gathered some more light tonight, and got a total exposure of 3h 30 minutes.

I've tried stretcing the levels of this exposure in Photoshop, having like 4-5 of them, then starting at one end, doing the masking tecnique and working my way back towards the lowest of the exposures which makes out the core.

The result however, is absolutely horrific. The nebula turns completely blue, and I am unable to avoid getting borders between each of the layers. You can clearly see the mask borders in the image...

I'm at my wits end I tell ya... my witts END....

Any input is greatly appreciated. Uranium - you talked about a super-multi-layer M42 pic you've got... Have you by any chance got any pointers for me? The tutorial you gave me obviously does not involve stretching, or multi-layer beyond two...

[Alveprinsen]

It seems that the server on which my pictures are - is down. I've given the upload system here a try instead.

This is the horrible result I was referring to:

To the left, the horrible result... To the right, the less horrible result.. Although it too shows a clear transition between the layers. Even though I've done my best to hide it. :/

Alveprinsen.