Dancing under a near full moon

[pyrasanth]

Well not so much dancing more imaging of M101

I wanted to prove to myself  that I can still get good HA data under a near full moon provided  equipment & processing is good.

The image below is 9 hours or so of HA data shot from the 17-20th April under a near full moon.

I used PixInsight to process the Atik 460 2x2 Bin data & consists of 18 30 minute subs and 2 x 20 minute subs. The data looked pretty much burnt out but I used a masked stretch then ACDNR to remove any noise. I found DBE increased the noise so it was not DBE corrected before or after the stretch.

I then used Noels actions to enhance the Galaxy which came out really bright so I layered the 2 versions reaching the compromise posted below. I may go for one more HA session tonight weather permitting just to increase the SNR & remove the last of the heavier noise.

Good guiding & focus was essential as well as good flat field correction so Focuslock & the ONAG are proving there worth.

So the proof is below- we can image HA with good results on a faint target.

So I should have a good HA layer for M101 preparing me for the LRGB marathon in the next few weeks.

 

[Guest]

Nice use of PI and good results there - I'm thinking of getting a mono camera for this reason - moonlit imaging :-)

David

 

[pyrasanth]

3 minutes ago, David_L said:

Nice use of PI and good results there - I'm thinking of getting a mono camera for this reason - moonlit imaging :-)

David

 

Well- this sounds daft but I only learnt about the masked stretch at 2.00 am this morning when somebody on that rival forum we cant talk about critically looked at my M51 image & told me about the masked stretch tool to prevent highlights blowing out. It really is brilliant & allows a full stretch without blowing out the cores of bright objects. I'm going to be using that tool for ever from now on. You need to stretch first then remove noise.

Don't think about a mono camera- get the Atik 460 mono- ask Olly- he like me thinks the camera is brilliant. I also have an Atik 11000 but I need to upgrade my ONAG to use it in the way I want.

Clear skies to you- a miracle struck I've had 2 good nights this week despite the moon.

[laudropb]

Very nice capture.

[Grant]

10 minutes ago, pyrasanth said:

somebody on that rival forum we cant talk about

I don't know what you are referring to - there is no rival forum that you cannot talk about on SGL - we have lots of links and discussion on all astro forums here and would never dream of censoring something like that.

If anybody ever feels that discussion of another website or forum is censored on SGL then please let me know.

[pyrasanth]

6 minutes ago, Grant said:

I don't know what you are referring to - there is no rival forum that you cannot talk about on SGL - we have lots of links and discussion on all astro forums here and would never dream of censoring something like that.

If anybody ever feels that discussion of another website or forum is censored on SGL then please let me know.

This was tongue in cheek.....relax! but.....I make no secret about the cloudynights forum sometimes becomes unfriendly.

[Guest]

23 minutes ago, pyrasanth said:

Don't think about a mono camera- get the Atik 460 mono- ask Olly- he like me thinks the camera is brilliant. I also have an Atik 11000 but I need to upgrade my ONAG to use it in the way I want.

Clear skies to you- a miracle struck I've had 2 good nights this week despite the moon.

Thanks very much for the advice - and if Olly gives it a thumbs up it must be worth looking at :-)

David

[alan4908]

A very good image !

1 hour ago, pyrasanth said:

I wanted to prove to myself  that I can still get good HA data under a near full moon provided  equipment & processing is good.

Recently, I  asked myself a similar question but I wanted to know when I could image Deep Sky Objects with the moon up. After a bit of experimentation, I also found the quality of the image (LRGB and NB) also depends on where the object is in relation to the moon and the moon's phase. Since I wanted to go down the automated imaging route, I also discovered that the automation program ACP implements a "moon avoidance" ability via the Lorentzian algorithm. 

I now implement the Lorentzian algorithm via ACP for image acquisition. This takes into account the filter type and the moons phase and works out the angular distance the object will be from the moon, if the object is more than the angle then the image is acquired. The algorithm was created by the Berkeley Astronomical Department and can also be used for LRGB acquisition.  So, now, I  just leave it to ACP to decide whether to acquire the image or not.

On the planning front, I also use CCDNavigator which also incorporates the Lorentzian method and indicates if the object is going to be suitable for imaging at a particular time/date, taking into account the filter type, moon's phase etc.  

Alan

[Daniel-K]

i really like that, it looks stunning

[pyrasanth]

2 hours ago, Daniel-K said:

i really like that, it looks stunning

Thanks- I captured another 2 hours of HA data last night which I will add into the mix. I think I will need one more good session with the moon out of the way my guiding S/N ratio was very low last night but I think the conditions went a bit hazy as well later on.