The "No EQ" DSO Challenge!

[Filroden]

53 minutes ago, wxsatuser said:

Although both images are very good the first is closer to true colour.
Most of M42, contrary to most images you see, is blue reflection nebula.
This blue is mainly around the outside with the inside containing Ha, there is some teal around
the Trapezium for the OIII.

 

I know what you mean, but I've not done anything different in terms of balancing colour in the second version. I've played with the histogram and if I pull back the green the image goes very magenta. Adding more blue doesn't seem to help. I've just don't seem to have as strong a signal in the blue channel in the second version. I suspect I didn't fully remove colour gradient in the second version which could explain the hue.

Anyway, here's a quick play to bring the histogram roughly to the same balance as in version 1 but the colours are still very different.

And another version with some more work in Lightroom (I've soft proofed this one against a Fuji Gloss paper as I'm going to get one of these versions printed once I'm happy with its look)

 

Edited December 3, 2016 by Filroden

[happy-kat]

In case you haven't opened it yet Ken but my canon ef 85mm f1.8 manual focus is fly by wire so it has to have a camera body attached to focus I forgot to mention that yesterday.

[Filroden]

2 minutes ago, happy-kat said:

In case you haven't opened it yet Ken but my canon ef 85mm f1.8 manual focus is fly by wire so it has to have a camera body attached to focus I forgot to mention that yesterday.

Just going to check it now. It had a switch to flip between auto and manual focus so I assumed it was like my other lenses.

[happy-kat]

It does have switch but it is manual fly by wire, my pancake lens is the same.

Edited December 3, 2016 by happy-kat

[Filroden]

20 minutes ago, happy-kat said:

It does have switch but it is manual fly by wire, my pancake lens is the same.

Yeah. It doesn't focus so I have to decide whether to use it on the DSLR or take it back. Unfortunately *someone* put the box in the recycle bin and it was cleared yesterday. I don't think that matters for returns but it's embarrassing!

[Filroden]

Well, if the weather clears as forecast tonight, this will be my test target for the new lens/DSLR combo. Just managed to attach the camera to a bar, so I can mount it. Just afraid that the DSLR isn't sensitive enough to Ha, even with an f1.8 lens. If all goes well, I might shift over to Orion once it rises high enough.

 

[parallaxerr]

Just looking in the exact same region for tonights target, specifically the Flaming Star. But like you say, camera sensitivity may be an issue.

Horsehead is still a tad late at night for me!

 

Edited December 3, 2016 by parallaxerr

[Filroden]

Not sure this will work but I recently reprocessed my recent image of the Flaming Star Nebula using the new technique I learnt to stretch the background. It's still very faint! Here's a before/after animation.

[happy-kat]

We have tracking.... 'Enif' 30 seconds very slight trailing. 50mm vintage lens f2.8 Baader Neodymium filter iso 800 30s 1100d Virtuoso mount with synscanv3 handset

But there is a huge but I can't aim anywhere else (even vega produces horrible long star trails) I think this is down to I am unable to use stars to align far enough apart. So until I chage location or something interesting appears in my narrow south view I'm stuffed. GoTo works flawlessly so there is enough alignment for that.

Edited December 3, 2016 by happy-kat

[Filroden]

9 hours ago, happy-kat said:

We have tracking.... 'Enif' 30 seconds very slight trailing. 50mm vintage lens f2.8 Baader Neodymium filter iso 800 30s 1100d Virtuoso mount with synscanv3 handset

But there is a huge but I can't aim anywhere else (even vega produces horrible long star trails) I think this is down to I am unable to use stars to align far enough apart. So until I chage location or something interesting appears in my narrow south view I'm stuffed. GoTo works flawlessly so there is enough alignment for that.

It's really odd that your tracking is direction dependent. Once you're aligned and tracking, surely you should have the same accuracy (or inaccuracy) everywhere? Before I started using the StarSense again, I was only aligning on three nearby stars - usually Capella, Mirflak and Aldebran. Not the widest of star fields! However, it gave me pinpoint accuracy between them (my current main imaging area) and in the surrounding area (so Andromeda, Cassiopeia, etc) and my tracking was good. I guess your mount works in a different way.

[The Admiral]

10 hours ago, happy-kat said:

We have tracking.... 'Enif' 30 seconds very slight trailing. 50mm vintage lens f2.8 Baader Neodymium filter iso 800 30s 1100d Virtuoso mount with synscanv3 handset

But there is a huge but I can't aim anywhere else (even vega produces horrible long star trails) I think this is down to I am unable to use stars to align far enough apart. So until I chage location or something interesting appears in my narrow south view I'm stuffed. GoTo works flawlessly so there is enough alignment for that.

What stars are you using for alignment?

I only use 2 star alignment about the region I'm imaging, and both GOTO and tracking are usually good.

Ian

[happy-kat]

Last night it was vega and enif. I'll try again when the camera hotshoe mounted rdf arrives.

[Filroden]

My turn for mount trouble again. This time my azimuth drive stopped responding. I was panicking for a while when I was seeing star trails on a 15s exposure with an 85mm lens! Tried resetting the mount but nothing. I usually have to leave it and it fixes itself. Thankfully it also clouded over so I'm not missing imaging time. 

Still, the few star trails I took looked reasonable at f2, ISO 400 and 30s.

*edit* After lots of setting changes in the handset it just started working again. I think I upset it by disconnecting the StarSense when swapping from scope to camera so I may look into the shoe adapter or just leave the StarSense on the eyepiece tray when I swap. 

Such a shame as it cleared up nicely by 10  and the forecast is bad for the rest of the week. 

Anyone got advice on exposure/ISO for wide field at f2? I was thinking of trying 2minutes at ISO 100 and working back from there. 

Edited December 5, 2016 by Filroden

[The Admiral]

A couple of nights ago I re-targeted NCG6888, the Crescent Nebula. Previously, I'd taken 121 subs and this time I took 241 with the target much higher in the sky, and I think under slightly better conditions. I rejected a number of frames as showing what I regarded as 'significant' trailing which left me with 88 from the first session and 163 from this last, or 251 in total, and over double what I used for my previous post (https://stargazerslounge.com/topic/228101-the-no-eq-dso-challenge/?do=findComment&comment=3091544). These were stacked in AA using bias for darks and the flats from this last session for both sets. I processed in ST, but I found this tricky and, to be honest, my results always look a bit messy. This I think is largely due to the very high star density in this area of the sky, and also I stretched heavily aiming to get every bit of nebula extracted. I felt I needed to do a bit of tweaking in LR after the event as well.

The full image is a bit overwhelming, so I've also posted a small version which I think gives a better impression of the nebula field, as individual stars are less able to be seen. I can't say this image makes me really happy, but it is a record. I think in reality I'm scraping the bottom of the barrel here as I suspect there are too few photons landing on each pixel to get a decent picture, however many subs I use.

 

The Bubble Nebula is also lurking in the top left nebula, by the dark dust lanes within it, not that you can see it

 

Ian

Edited December 5, 2016 by The Admiral

[Filroden]

12 minutes ago, The Admiral said:

A couple of nights ago I re-targeted NCG6888, the Crescent Nebula. Previously, I'd taken 121 subs and this time I took 241 with the target much higher in the sky, and I think under slightly better conditions. I rejected a number of frames as showing what I regarded as 'significant' trailing which left me with 88 from the first session and 163 from this last, or 251 in total, and over double what I used for my previous post (https://stargazerslounge.com/topic/228101-the-no-eq-dso-challenge/?do=findComment&comment=3091544). These were stacked in AA using bias for darks and the flats from this last session for both sets. I processed in ST, but I found this tricky and, to be honest, my results always look a bit messy. This I think is largely due to the very high star density in this area of the sky, and also I stretched heavily aiming to get every bit of nebula extracted. I felt I needed to do a bit of tweaking in LR after the event as well.

The full image is a bit overwhelming, so I've also posted a small version which I think gives a better impression of the nebula field, as individual stars are less able to be seen. I can't say this image makes me really happy, but it is a record. I think in reality I'm scraping the bottom of the barrel here as I suspect there are too few photons landing on each pixel to get a decent picture, however many subs I use.

The Bubble Nebula is lurking in the top left nebula nebula, by the dark dust lanes within it, not that you can see it

Ian

That's a lot of stars! It's hard to tell if you're not getting enough data/pixel. If anything, your stars look a little square but that might be through conversion to a lower resolution jpg. You could try a drizzle integration (is that easy to do in AA?) and reduce it back down after all the processing.

My only suggestion would be in Lightroom to adjust the hue of the magenta into the red. Your yellows are nice and golden so I don't think there is a cast.

I ran it through a quick star erosion process in PixInsight, at 30% blend I think it helps the image a little. Anything more than 30% and it makes it look too processed. I think  it's just a very difficult target - a bit like the North American Nebula because of the rich star field.

[happy-kat]

Oh you just made my day :-) Ian's image and Ken's comment re north American nebula.

Virtuoso mount 50 x 6 seconds 1100d iso800 baader neo...filer vintage 50mm lens f2.8 plus bias and flats. Bright star is deneb. I thought I'd got a messy mash but your star field comments have cheered me up. 

[The Admiral]

Thanks Ken. I think I'm actually oversampling, but I software binned to 25%, and on a whim tried the Flux option in ST which does some sort of fractal processing - I need to check that one out .

As for colour, I agree more red than magenta, but so far if I'm not careful the stars around the nebula take on a greenish tinge.

Of course, this is often imaged in narrow band, which will take out the star intensity I guess. Will NB be your next step?

Ian

[Filroden]

5 minutes ago, The Admiral said:

Will NB be your next step?

It is tempting! Even if just for bragging rights and show a SHO image taken from an alt as mount

You can also develop the image twice. Once to get your stars really sharp but ignore background (I.e very little stretching) and a second removing the stars and really go at the background. The two can then be blended. It's sort of how I've tried to enhance the NGC1333 but I took it a little far!

As for green, if you use the detailed colour sliders in Lightroom on the hue setting then you should see any green. It really only adjusts a limited colour range. 

Edited December 5, 2016 by Filroden

[Filroden]

10 minutes ago, happy-kat said:

Oh you just made my day :-) Ian's image and Ken's comment re north American nebula.

Virtuoso mount 50 x 6 seconds 1100d iso800 baader neo...filer vintage 50mm lens f2.8 plus bias and flats. Bright star is deneb. I thought I'd got a messy mash but your star field comments have cheered me up. 

Amazing for less than 5 minutes of integration. You can just start to make out the Pelican. 

[The Admiral]

4 minutes ago, Filroden said:

It is tempting! Even if just for bragging rights and show a SHO image taken from an alt as mount

You can also develop the image twice. Once to get your stars really sharp but ignore background (I.e very little stretching) and a second removing the stars and really go at the background. The two can then be blended. It's sort of how I've tried to enhance the NGC1333 but I took it a little far!

As for green, if you use the detailed colour sliders in Lightroom on the hue setting then you should see any green. It really only adjusts a limited colour range. 

Yes I've just tried the hue sliders but they don't really make much difference. May be some more tinkering.

I guess that the only problem in splitting the stars from the nebulae is the creation of a mask, but my attempts so far have been dismal on account of the abundance of stars. Again, something I'd need to spend some time on.

Ian

[Filroden]

Maybe if you create the mask from the undeveloped or lightly developed image you should isolate the stars a little easier? You might miss the fainter stars which might have similar brightness to the nebula but they shouldn't overpower as much as the many brighter ones. 

[Nigel G]

I tried a 55mm image of Orion and Rosette last night, I took 60x60s ISO 800 and 45x30s ISO 1600 with flats and bias.

Its horrid, I can see Orion- Running man, Flame- H/H- and Rosette but the noise is horrendous, also theres a spiral from the lens throughout the whole image, I can't seem to do anything with it. This is my first total disaster, I'm trying different stacks but don't hold much hope. I think theres just too much LP from below.

Going to have to try something else, different settings maybe.

Ahh well, win some loose some :/

Nige.

[happy-kat]

Was that a kit lens? or another lens you used. Did you use some form of shield on the lens? I have sheilds made from flowerpots that I have flocked.

[Stub Mandrel]

23 minutes ago, happy-kat said:

Was that a kit lens? or another lens you used. Did you use some form of shield on the lens? I have sheilds made from flowerpots that I have flocked.

:-)

I have a hood for a 400mm lens made out of the body of an aluminium fire extinguisher! Flocked  too :-)

[Filroden]

2,000 posts! Keep alt/azing!