The Admiral

Thanks all for your comments and 'likes'.

3 hours ago, Roy Foreman said:

It is good to see the flame looking closer to it's true yellowish colour rather than red as in so many other images.

I'm not sure how its colour will change when the Ha is added in, as it appears to be quite bright in Ha too.

Ian

18 minutes ago, SteveNickolls said:

A friend produced this ghostly starless image for me using Star Net ++-

It certainly gives the nebula a more solid appearance, though I do tend to like structures anchored by stars, but not too many of 'em!

Nice captures Steve.

Ian

And why not? It's a stunning object which demands attention!

The first image is wideband, taken with an Askar FRA400 and ZWO ASI553. Alnitak is quite dominant, and I am wondering if the blue spots on NGC2024 (Flame Nebula) are real or come from spurious reflections from Alnitak. This is a result of 100x2m subs (3.3h) after discarding the rogue ones.

The next night I used an L-eXtreme dual band filter. The following is an Ha extracted image. It's a result of 50x3m subs (2.5h).

The filter does induce rather harsh star halos.

All processing is performed in APP, with final tweaking in Lightroom. Both need more data of course. Now all I need to do is blend them .

Thanks for looking.

Ian

Thanks Steve. Somewhere between 4 and 5, nearer to 5 I guess. I don't measure it. Given the amount of cloud passing through and the interruptions with guiding, I suspect that transparency wasn't great.

Ian

That's nice! I had a go at this with a dual passband filter and 533mc, but could only dedicate one evening to it, and that was blighted by intermittent cloud and poor seeing. 15 hours plus is great. It makes a difference!

Ian

Thanks for that detailed reply Leo. I've no axe to grind here, I'm only going on 3rd party information. In fact, the other morning I was looking out of the window at the dawn sky and noticed how distant contrails could be mistaken for something else. When I suggested that to my wife she was not convinced, but then, she is not familiar with how meteors look. It was our son who found the newspaper article through the wonders of the internet. He did have a look at FlightRadarat the time but said he couldn't see anything it might have been, but I don't know over what distance he was checking. I'm not sure whether FR covers all military flights either.

Ian

36 minutes ago, Leo S said:

There were 3 events reported between 7-8 AM

Thanks for detailing all this. When you say 'reported', by whom and to whom?

Do you really think the object in the photo in the newspaper article is a contrail?

Of course, I didn't observe it myself, unfortunately. I'm going by what my family were saying.

Ian

The last time I imaged this object was six years ago, using Alt-Az imaging, a Fuji camera, and 102mm APO. I've not been very prolific in the intervening years, but I now have lighter weight gear, an AM5 EQ mount and Askar FRA400, and am learning to process dual band images.

Here is an HOO rendition of NGC2244, produced by APP and finished in Lightroom. There were 54 x 3m subs (2.7hr) with the ASI533 and Optolong L-eXtreme. A series of darks, flats and dark-flats were also taken. During the sequence I was plagued by cloud!

Thanks for looking.

Ian

Looking at my Android settings, I see that I am supposed to be on v2. 

19 hours ago, Elp said:

don't know why they changed the PA routine. I easily used to get around 20-30 arc seconds within around 3 minutes of setting up, now it's very difficult to get below 1 arc minute within ten minutes.

I concur with this. I never found PA to be very quick, and generally I use the all sky PA as I don't have a decent view of Polaris. But now, iterating to alignment seems erratic, and often it reports solving failed. I am wondering if the fact that tracking doesn't seem very sticky now is causing problems. I often give up nowhere near decent alignment, and just carry on, leaving the guiding to make up for it. Can't waste that much time. Strangely, when I am aligned to a target, tracking stays on. 

Ian

Don't be put off by its low weight. It has the high torque of a harmonic drive, and can shift heavy-weights about without a problem. I think the real question is, is weight a necessary representation of ability? And, what weight are you able to manage? A more modern approach to manufacturing can help to keep weight lower. I think that there are two issues you need to consider, the weight and focal length of the scope that you are going to put on it, and the guiding limit of current harmonic mounts. Some folk like to use a pier or a heavier tripod to add stability, particularly with heavier gear. The AZ EQ6 has 3x the head weight, and has a tripod 3x the weight, and performance is really not directly comparable.

I think that the issues I've found are really a problem with the software of the ASIAir, not the mount, but I haven't got to the bottom of it yet.

Ian

My wife, our son and his wife, noticed a light coloured object moving at a steep angle in the Eastern sky this morning, moving towards the ground, when it went behind some trees. This was from the Cotswolds between about 7am and 8am. Our son says he saw it again about between 9am and 10am.

I wouldn't have expected to be able to see a meteor in daylight (or perhaps dawn), but given this report of a similar object over Clifton I guess it's possible, though may be space junk.

https://westbridgfordwire.com/object-seen-in-the-sky-over-clifton/

Has anyone heard of today's event or have seen any reports of today's sighting?

Ian

Thanks Olly, perhaps I should get to grips with Affinity. I have extracted the Ha from the dual band output, which of course is grey scale. Presumably that will have to be assigned as red. The L-Extreme has given me ugly halos around Alnitak and another star, so I wouldn't want them polluting the broadband image. Would I be correct in that a starless Ha image would allow me to achieve that and give better star colours? APP can remove stars, apparently, though how it would deal with the halos I'd need to investigate.

Ian

37 minutes ago, wulfrun said:

standards

Yeah, so that they can be relaxed later by the government to aid profitability. Just look at the lip-service paid by the water authorities when it comes to sewage discharge. Don't get me started 🤐. I'll get me coat.

Ian

I think that is very sad for future populations. Problem is, it seems to be difficult enough trying to deal with global warming, it is hard to see much effort being devoted to this, even if there are in fact ramifications for energy consumption. I suppose at a national level, it should be possible to reverse the trend, but don't hold your breath!

Ian

OK, thanks. APP has a routine for extracting just the Ha, which is what I have done.

Ian

Something you experienced imagers do all the time, but I'm new to processing narrow-band images, so a bit of guidance would be much appreciated. I fully expect, though, that there'll be as many ways as there are imagers!

I've just acquired an RGB image of the Horsehead and Flame nebulæ and environs, using a OSC, and I've also got my data for Ha using a dual band filter (L-Extreme).

Note that I do not have Pixinsight or Photoshop. I do have Affinity Photo, but I'm pretty new to that and wouldn't call it familiar. I stack and process using AstroPixel Processor. The most logical way would seem to treat the Ha as an L layer, but what would be the most effective way of combining these two datasets?

Ian

1 hour ago, david_taurus83 said:

Have you updated to the latest ASIAir version?

Well, like Stevie, not knowingly. I normally see an automatic update when I first start up and I haven't seen one for a while. I'm on v. 2.0.10.46 I think, and I'm not sure how one would go about preventing an upgrade.

17 minutes ago, knobby said:

Maybe the dew heaters ? a 5 amp power brick might struggle to actually supply 5 amps reliably

The total current draw doesn't seem as though it would stress the power pack. Only about an amp for both the dew heaters, the ASIAir itself, and the camera and cooling. The latter was minimal, as I'm running at -5°C, and the external temperatures were low. IIRC it was only at a few percent of of max.

Thanks both for your inputs.

Ian

Addendum. I've just operated the mount through the ASI Mount app, connecting via the handset. Seeking the home position worked without problem. Interestingly, the mount tracking was set to OFF. Not sure why that should be, but I've now set it to SIDERIAL.

I've also connected the mount up to the ASIAir Plus and operated it that way. Tracking appears to be sticky and it moves to the home position as it should.

So why should it have behaved erroneously last night?

Ian

At last, the weather gave a bit of time to get some imaging done last night. It didn't exactly go smoothly, and cloud curtailed the evening.

Apart from the usual difficulties doing PA with the all-sky feature, though that's another story, two issues cropped up which I hadn't seen before.

1. When I had pointed the scope to the southern skies, I did a quick image to see what stars there were that I could focus on, but clearly, tracking was off. This was despite the little 'fly-out' for mount control showing that tracking was supposed to be on. I went in and switched the tracking on, but I found that it wasn't sticky. Sometimes it appeared that it held for a while, other times it would flick back off within a few seconds. In desperation I slewed to my target and started guiding, and then it seemed to stay on. Surely it's not dependent on guiding being active? It hasn't been before.
2. When I first started the night up, I sent the mount to home (it was actually already there from the previous session). This it did in the usual way, by slewing, and then back-tracking at slow speed to line up. When I sent the mount to home after the imaging session, it did the normal slew to just past the home position, and then back-tracked, but this time it kept on moving. I cancelled the home request, and repeated it. Once again it it continued to slew on the back-track. Never had that before.

Anyone got any ideas? I plan on imaging again this evening if the weather obliges. I power the mount and ASIAir separately, using 2 x 5-amp Lynx Astro power bricks. They should be OK. I had 2 dew heaters running off the ASIAir but they weren't drawing anything excessive, and of course the power demands from the ASI533 for cooling were minimal.

Ian

6 minutes ago, ollypenrice said:

Certainly prioritze broadband. The Ha contributes mainly to the 'curtains' behind the head, allowing you to bring out the striations and the dappled structure of the nebulosity below the curtains. Depending on your optics and how well they control Alnitak, you might consider some very short subs to help you control that star. It can easily bloat in some refractors. Because the star is so bright, there is no need to shoot many subs. Just a few will do.

NGC2023 is beautiful and broadband only.

Olly

Thanks Olly. I did image the HH and surroundings some years ago, with a Fuji mirrorless camera, and was pleased with that broadband result, except it needed a lot more exposure. I now have a totally different rig and an astro camera, so I'm hoping to better do it justice. I'd want to include NGC2023 too, so it looks like a broadband approach is a priority. I'm not sure how the new rig will withstand Alnitak 🙂, but thanks for the reminder, a few short subs could be taken. It would be good to get NB to blend when the opportunity arises later.

Ian

10 hours ago, Stuf1978 said:

I always think a combination of both narrowband and broadband data suits this area well

7 hours ago, The Lazy Astronomer said:

HH definitely looks best in broadband colour, with Ha enhanced reds.

Thanks both. Logistically, doing both may be a bit difficult, given our weather here in the South, so I think I'll start off in broadband and if possible add NB later. At least that way the HH will be fully represented.

Ian

The HH is rich in Ha, so it would make sense to image that with NB, but would that not be ideal for the associated Flame nebula, nor for NGC 2023 close by.

Any thoughts please? I can image with a dual band filter or in white light,  both with a colour camera.

Ian

It's nothing new I'm afraid. Cuiv has done measurements on a range of filters and has discovered some are off the mark. See for example, https://youtu.be/VkSvpOLlD2Y and 

Unless suppliers do independent testing, and rejects those that are out of spec, we will all be none the wiser.

Ian

I prefer to use a spirit level across the top of the tripod for levelling, as I don't find the built-in bubbles to be very sensitive.

Ian

Come on, give me clue 🙂. Where am I supposed to be looking?

Ian