West Veil + Pickering's Triangle - Ha

[STEVE333]

I'm loving this NB setup. This is Ha data taken on two nights over the last few days (nearly full moon). The first night I only captured 9 frames before the fog rolled in. The second night (last night) the sky was clear with no clouds or fog from 10:30 pm till 2:40 am. Although I heard a lot of fireworks during the entire time only one of the images showed any artifacts (a bright streak) and the PreProcessing removed it completely.

The full moon did increase the noise level.

• Moonless background flux = 53 photons/sec
  Full Moon background flux = 137 photons/sec
  Added noise factor = sqrt(137/53) = 1.6

Thus, the moon increased the noise by about 60%! Makes me wish I had a 3nm Ha filter rather than my current 7nm filter. That would have reduced the noise by a factor of about 1.5. Note to self: Purchase 3nm Ha and Siii filters. I already have a 3nm Oiii filter.

IMAGE INFORMATION:
WO Star 71 telescope, 7nm Ha filter, ASI1600MM Pro, MMAG Autoguider, CEM40 mount
33 x 600 sec Lights (total Exposure 5 hr 30 min), Master Flats and Darks
APT, PHD2, PixInsight

Ha Image
W_Veil_Ha by STEPHEN KING, on Flickr


Processing was carried out using a starless version (shown below) created using the new starless approach.

Starless by STEPHEN KING, on Flickr


Hoping to capture some Oiii tomorrow tonight if the forecast holds, and, if my body holds out. Definitely a nap tomorrow afternoon!

Thanks for looking.

Steve

[Ylem]

Lookin' good Steve!

[jthommes]

Looks good Steve. I assume more filters are coming on this target?

So the 3nm filters will also increase contrast - but won't they also increase your need for longer exposure time? My thinking is that if you decrease noise (a good thing) and you decrease signal for a similarly timed exposure as that of 7 nm (a bad thing), your S/N has marginal returns unless you increase exposure?

[STEVE333]

H Jim and thanks -

Your thinking is correct for a broadband source like a galaxy.

For the nebulae the situation is different. Hydrogen, Oxygen, and Sulphur gasses (and others) emit most of their signals at specific wavelengths. The Ha filter is designed to allow all of the Hydrogen alpha emission (red) to pass. The Ha emission is very narrow and essentially all of it will pass through a 10nm, 7nm, or 3nm wide filter. The benefit of the narrower filter is that it rejects more of the broadband signal (sky glow and moon glow) and that reduction in the transmitted broadband signal is what reduces the noise.

The same is true for the other NB filters.

This is the reason so many of us taking data from a high LP location have switched to NB imaging. It allows us to get good data even with bad LP.

Hope this makes sense.

Steve

[MariusD69]

Awesome! Well done, Steve!

[Juno16]

Looks great Steve!

Really glad that NB is working so well for you. Amazing that even with the higher noise from the moon, you captured some really nice Ha data.

Also, glad that you can get out. Five weeks of clouds for me and all that I did was mention in a post that I am planning on an OSC camera around years end!

Nice work Steve. looking forward to more!

[Hankmeister3]

It's amazing what you can capture under moonlit Bortle 7 or 8 skies. Especially something as ephemeral and delicate as any part of Veil Nebula. I'm really gobsmacked by that capability. Thanks for sharing, Steve.

"... before the fog rolled in." I remember those nights when I lived in San Clemente, Steve. There was a stretch there in 1980, for about a month, when the fog rolled in like clockwork around 2:30 and 3:00 AM virtually every day. That made Interstate 5 so hazardous driving into LA at 6:30 in the morning.

[Gordon]

Congratulations Steve on having your image selected as todays TSS APOD!

app.php/article/7-6-2020-tss-astrophoto ... of-the-day

[STEVE333]

Thanks Gordon. This was a surprise. Much appreciated.

Cheers

[Makuser]

Hi Steve. A superb image of the Western Veil and Pickering's Triangle in Ha light and I hope to see your other NB filter data added soon. Thanks for sharing this capture jewel with us on here Steve, and congratulations on winning the TSS APOD Award today.

[TheButcher]

Very nice Steve! Can't wait to see some OIII in there!

[helicon]

Excellent image Steve! Thanks for sharing.

Also, congrats on winning the APOD for today.

[Mac]

Great capture Steve. Looking forward to the addition of Oxygen to your image. I need a wide FOV scope like you're using.

Congrats on APOD

[STEVE333]

Looks great Steve!

Really glad that NB is working so well for you. Amazing that even with the higher noise from the moon, you captured some really nice Ha data.

Also, glad that you can get out. Five weeks of clouds for me and all that I did was mention in a post that I am planning on an OSC camera around years end!

Nice work Steve. looking forward to more!

Thanks Jim - Some things are better kept to ourselves (like mentioning you want a new camera)

It's amazing what you can capture under moonlit Bortle 7 or 8 skies. Especially something as ephemeral and delicate as any part of Veil Nebula. I'm really gobsmacked by that capability. Thanks for sharing, Steve.

"... before the fog rolled in." I remember those nights when I lived in San Clemente, Steve. There was a stretch there in 1980, for about a month, when the fog rolled in like clockwork around 2:30 and 3:00 AM virtually every day. That made Interstate 5 so hazardous driving into LA at 6:30 in the morning.

The filters are making an incredible difference in the data I collect. Even though I'm only in Bortle 5 it's still bad enough.
Driving from San Clemente (a beautiful little town) to LA everyday! Wow, what a commute. glad you survived it.

Hi Steve. A superb image of the Western Veil and Pickering's Triangle in Ha light and I hope to see your other NB filter data added soon. Thanks for sharing this capture jewel with us on here Steve, and congratulations on winning the TSS APOD Award today.

Very nice Steve! Can't wait to see some OIII in there!

Great capture Steve. Looking forward to the addition of Oxygen to your image. I need a wide FOV scope like you're using.

Congrats on APOD

Thanks All - Hopefully getting the Oiii tonight. Got about 1 1/2 hour nap which should help.

Steve

[Graeme1858]

Some lovely detail there. I hope your Oiii capture was equally productive last night.

Congratulations on the APOD.

Regards

Graeme

[BABOafrica]

Its' been a while since I posted anything on the AP threads. Logged on today and saw your APOD.

Just wanted to congratulated you!

BABO

[STEVE333]

Its' been a while since I posted anything on the AP threads. Logged on today and saw your APOD.

Just wanted to congratulated you!

BABO

Thanks BABO, and, welcome back. We've missed you.

Steve

[yobbo89]

the starless is looking good , a realy nice b/w image !

[JohnP_1]

Beautiful work Steve. Glad you are enjoying it.