Eye of God - testing Riccardi reducer - 26 hours of Ha

[Slawomir]

Hi all,

To date I only made a few brief attempts at using Riccardi reducer, as I found imaging with a short 4"refractor at f/4.5 more demanding than much more casual f/6.

Thanks to Glen's and Greg's clarifications on calculating correct spacing when accounting for thickness of filters in the imaging train, I corrected the spacing and star shapes have improved. Thank you Glen and Greg very much.

Humidity has gone up a bit so I may need to wait a bit for a few clear nights, nonetheless last night weather gods allowed me to collect initial 6 hours of 3nm Ha. I wish I had 5nm Ha to include nitrogen line.

I will most likely drizzle the data for the proper image.

6 hours of Ha: https://cdn.astrobin.com/thumbs/hggzGxvREqym_16536x16536_wmhqkGbg.j pg

10 hours of Ha: https://cdn.astrobin.com/thumbs/YHAK3Xgru3yp_16536x16536_kQt6vfvn.j pg

26 hours of Ha: https://cdn.astrobin.com/thumbs/evyPoI7vXM6W_16536x16536_kQt6vfvn.j pg

Thank you for looking
Suavi

[Peter Ward]

A simply impressive result
Very tight data. Nice :thumbsup:

[RickS]

That looks great, Suavi!

[Slawomir]

Thank you Peter and Rick for your encouragement. Hopefully I will be able to put together a decent for my aperture image of the Helix - this is one of the targets that I really wanted to image for some time.

[gregbradley]

You're welcome for the advice, its what this forum is all about.

Again I am gobsmacked. This is more like the data from a much larger scope.
The CFF/QSI combo is amazing and really well suited to each other.

Yes imaging at F4.5 is going to be much more challenging for squareness, tilt, spacing etc but in my opinion its worth the effort.

Greg.

[billdan]

Your off to a good start Suavi, I'm sure when you add data from your other filters it will be an excellent image. I'm surprised by how bright the centre area is with the Ha filter as that area is mostly OIII.

[willik]

Yes your there that looks good Sauvi HA
Martin

[Slawomir]

Thank you Greg, Bill and Martin for such kind feedback.

Got 10 hours of quickly processed (to check how much more of 3nm Ha I need before moving onto OIII): https://cdn.astrobin.com/thumbs/YHAK3Xgru3yp_16536x16536_kQt6vfvn.j pg

Thank you for looking
Suavi

[Stevec35]

Looks good to me. Looking forward to seeing the end result.

Steve

[strongmanmike]

Looks like quality data is being collected and a fine Helix is on the way Suavi...just needs more data :thumbsup:

Mike

[Placidus]

To get the faint chevron at the far left under those conditions is amazing.

[Slawomir]

Glad you like it Steve. Skies are relatively clear but there is high humidity at the moment and fog forms quite easily. I am hoping for a drier and cooler breeze from SE :prey:



Glad you like it Mike. Doing what I can with my 105mm and foggy nights...:)



Thank you Mike and Trish. I hope there will be a bit more signal in the outer regions in OIII. I may need to invest in a 5nm Ha or perhaps in a narrowband nitrogen filter...wouldn't mind having a go at exploring planetary nebulae with my small refractor.

EDIT: Found this link to a website showing Ha and OIII. It looks like I need to add more Ha to highlight the outer bits a tad more...

http://www.capella-observatory.com/ImageHTMLs/PNs/Helix.htm

[Atmos]

It's looking fantastic so far Suavi, that 4" really punches above its weight!

[Slawomir]

Thank you Colin for your encouragement.

Although it is not a 4" benchmark-setting scope like FSQ106, but at about 60% of the cost of FSQ, it does a decent job.

[Ryderscope]

Excellent extended detail and nice field. Well done Suavi.

[Slawomir]

Thank you Rodney.

Now I am up to 17 hours of Ha. Reaching the point of diminishing returns quickly.

[Slawomir]

Hi all,

Last night weather and equipment allowed to add a few more hours - 3nm Ha adds up to exactly 24hrs. It is my personal best/deepest for a single filter for any given dso.

Background noise of drizzled stack is at about 1.5 ADU (st.dev), and the faintest bits are just 1.4 ADU above the background in 15-minute subs, which at gain of 0.26 e/ADU equates to about 1 photon every 45 minutes, if my maths is correct.

https://cdn.astrobin.com/thumbs/Rc9jz0ZaWmbN_16536x16536_kQt6vfvn.j pg

I think I will try taking advantage of the New Moon and start OIII.

Thank you for looking
Suavi

EDIT: I remembered that Mike and Trish took a very deep photo of this PN in Ha, so I looked it up: https://photos.smugmug.com/Category/Planetary-Nebulae/i-8NCj6fP/0/c5ec63dc/X3/Helix%20H-alpha%2068%20hrs%202x2%204%20hrs%20 1x1-X3.jpg

:eyepop::eyepop::eyepop:

[codemonkey]

Lookin' good Suavi! Looking forward to the final product.

You're doing some epic integrations these days... I usually manage about 2hrs a night in terms of actual data collected, takes me forever to get the kind of integrations you're cranking out in a few days.

[Slawomir]

Thank you Lee.

I have been just lucky with the weather and our backyard is an enormous upgrade from all previous inner-city locations. Also, once I learnt to trust SGP to reliably run an overnight imaging session, I have been able to acquire much more data and much more easily. An obsy would be the next natural upgrade...one day.

Keeping fingers crossed for some more clear nights before the inevitable rise in humidity that spring attracts to North/Central QLD.

[multiweb]

Fantastic! You've got a lot more than my last attempt from home with the hyperstar. :thumbsup::thumbsup:

[Geoff45]

Great capture of the outer halo Suavi
Geoff

[Slawomir]

Thank you Marc and Geoff.

Started collecting OIII and for those interested, attached is a comparison of signals from OIII and Ha. Hopefully I will be able to go deeper with OIII during the next few moonless nights.

[Andy01]

Seriously deep impressive work in progress Suavi, should make a top shelf result when finished! :thumbsup:

[strongmanmike]

Lookin good Suavi :thumbsup: The OIII structure always fascinates me, challenging to reveal both it and the Ha well, in a final colour image though, so I look forward to seeing how you tackle this :)

Mike

[Slawomir]

Thank you Andy. If my processing fails short, at least I would like to make it my deepest image so far :)



Thank you Mike. Sounds like a challenging object to process well. Luckily I still have many nights of data collection ahead of me before I will need to start thinking about processing the data :)

[Slawomir]

Hi all,

Just an update on the progress - I think I have sufficient OIII data.

I will try adding some more Ha as it seems that only Ha master will be used for Luminance.

Attached is a crop of 30 hours of quickly processed OIII data - no noise reduction, no decon etc...

Astrobin: https://www.astrobin.com/full/362161/0/?nc=user

A link to a full frame: https://cdn.astrobin.com/thumbs/sjolAd-OjIU0_16536x16536_wmhqkGbg.jpg

I think spacing of the Riccardi is pretty close to optimal, so I will leave it as is.

Thank you for looking :hi:

[Stevec35]

The OIII looks excellent Suavi. Looking forward to the final colour version.

Cheers

Steve

[Geoff45]

This is going to look really good when you put it together Suavi.
Geoff

[strongmanmike]

Looking good still...I sense a Rolfesque exposure time coming on Suavi....;) :thumbsup:

Mike

[gregbradley]

A big effort there Suavi. I think it will pay off as the Helix is one of the premier astrophotography objects.

Greg.

[Slawomir]

Thank you all for such nice encouragement. Data looks quite good already, so in the coming weeks we will find out whether my processing routine is up to the task :lol:

[strongmanmike]

I'm a believer :D :thumbsup:

[codemonkey]

Stop teasin' us already Suavi! :-)

[multiweb]

Oiii channel looks great. Can't wait for the blend. :thumbsup:

[cometcatcher]

Very cool Suavi! Yes looking forward to the blend.

[Paul Haese]

The data is looking good Suavi. I look forward to seeing your final image. I particularly like the image scale. I went quite a bit further as you might remember and found after about 80 hours the changes were slow to show and so started reaching diminishing returns.

[Retrograde]

Looks very promising Suavi - you've gone really deep on this.
Can't wait to see the final composition!

[Slawomir]

Thank you all for your encouragement and very kind feedback.

Paul - 111hours for Helix is a very impressive and inspiring effort!

I'm up to about 38hours of Ha now and st.dev. in the background is around 1.3ADUs. OIII was collected on darker nights so 30hours also gives around 1.3ADUs of st.dev. for the background.

The faintest bits that I can confidently see get on average around 1 photon per pixel per hour of exposure. Subs are 15-minute long and I think it would have been better to try somehow longer subs. But random quickly passing clouds are not uncommon over here, so 15-minutes helps a bit in minimising the number of subs that need to get rejected.

Moon is bright again and getting close to the Helix, so I may need to wait a bit to finish collecting data.

Instead of trying to go deeper, I'm thinking of trying a third filter...:question:

[Atmos]

It might be worth trying a SII but I don’t think there is much in it from memory.

[h0ughy]

Certainly an interesting development of data, nicely working

[willik]

Very nice HA shot looks good Suavi
Martin

[Slawomir]

Thank you Colin, David and Martin. Weather has been generally quite conducive to imaging in the past month, so I was lucky to collect nearly 70hours of data so far.

Colin - today I got a nice surprise after work - a shiny 3nm NII Astrodon was waiting for me at home.

Just took the first test NII sub and the Helix shines very brightly in NII - significantly more signal than 3nm Ha and there are more structures visible too.

If the weather will cooperate after Full Moon, I might try Ha+NII for Luminance.

[troypiggo]

Already impressive in the monos - looking forward to the combination and NII data.

[Slawomir]

Thank you Troy.

It looks like the NII filter works nicely - no halos and no reflections, same as with my other Astrodons.

Got some initial NII data last night and have attached a comparison of OIII, Ha and NII for the Helix. NII needs much more data still so I will wait before I make an attempt at putting it all together.

In the meantime I have been experimenting with Ha master and slowly getting where I would like to get with the Luminance. Since neither OIII nor NII have the outer bows, I will most likely only use Ha for luminance.

Here is a gently processed Ha data with no decon and no noise reduction applied: https://www.astrobin.com/full/359357/G/

Thank you for looking

[Ryderscope]

Fantastic progress. Very encouraging and fine work.