The "No EQ" DSO Challenge!

[Filroden]

Well, I got two short runs at NGC1333 over the last couple of nights before the moon rose (and I had mount troubles). Here's the capture data for all four versions (1 & 2 used the same data but were processed differently). I've actually captured many more subs but for this v4 I was much more selective on which ones I used for the integration.

30s subs were captured at -20C at a gain of 300 and an offset of 50

45s subs were captured at -20C at a gain of 300 and an offset of 0

All captured on the Evo mount using the Skywatcher Esprit 80 and the ZWO ASI1600MM-C, and processed in PixInsight with a final boost in Photoshop.

Here's all four versions for comparison:

Version 1

Version 2

Version 3

Version 4

 

[Stub Mandrel]

20 minutes ago, Filroden said:

Version 4

 

Cooking on gas!

[Nigel G]

That's quite an improvement Ken, the dark areas much more visible.

Do you think adding 45s instead of increasing the amount of 30s made a difference?  Personally I think it does with the fainter details. 

Hope you get your mount sorted out.

Cheers

Nige. 

 

[Filroden]

2 minutes ago, Nigel G said:

That's quite an improvement Ken, the dark areas much more visible.

Do you think adding 45s instead of increasing the amount of 30s made a difference?  Personally I think it does with the fainter details. 

Hope you get your mount sorted out.

Cheers

Nige. 

 

I'm not convinced. I'm capturing the same number of stars but the 45s exposures increase their size. It probably does help with the fainter stuff and it's certainly easier to process. My camera has such a low read noise I think both e postures are effective. 

[parallaxerr]

Loving No.4 Ken  

[Nigel G]

52 minutes ago, Filroden said:

I'm not convinced. I'm capturing the same number of stars but the 45s exposures increase their size. It probably does help with the fainter stuff and it's certainly easier to process. My camera has such a low read noise I think both e postures are effective. 

I wonder if the increase in star size is due to mount errors,  the star moves around a tiny bit more. 

 

[Filroden]

2 hours ago, Nigel G said:

I wonder if the increase in star size is due to mount errors,  the star moves around a tiny bit more. 

 

I'm not sure. I'd just assumed it was the brighter stars' photons spilling over into adjacent wells. The longer the exposure, the more chance they extend. But given they are not saturated, I'm now not so sure why I see larger stars in longer exposures.

[SteveNickolls]

Excellent Ken, you are revealing the dust from out of the dark-well done.

Cheers,
Steve

[Stub Mandrel]

The photons from a star average out pretty much to a bell curve, bright at the centre and fading down rapidly to a long 'tail'. The longer the exposure the more of the outskirts get visible, especially after stretching. This is also why brighter stars 'look' bigger although in a perfect world they would all be points.

[Nigel G]

The weather man has promised clear sky's all night long. First proper clear sky for 2 months here in Essex. 

I have chosen my target, it will be high enough at around 11pm. Depending on wind strength, either scope or 210mm lens. 

Ken, I hope you have got your mount up and running again.

Hoping your sky's are clear too.

Nige.

[Filroden]

I have and managed to get 80 subs so far this evening. Hoping to have 180 before my target gets too high. 

[Stub Mandrel]

BAH cloudless skies most of the day, vega visible when I go to collect daughter from station at 5:00, watching Venus in clear sky at station until 5:25 return via morrisons by 6:10 and solid cloud!

[Stub Mandrel]

... and like yesterday it doesn't show on the satellite IR, although met office are forecasting it, just a gap around 8.

[SteveNickolls]

Good luck imaging tonight if you have clear skies. I wish now I had ignored 'clear Outside' and set up earlier as the current sky is mostly clear here but have made do with my binoculars. I've just come in from the cold and once warmed back up will go outside for a second session.

Yesterday I finished a portable screen to protect from the wind blowing down from the north, it should mean I will get a few more nights of imaging over the course of the year. :-) Here's a posed image from yesterday.

Objects clear the top of the screen at around 28 degrees elevation. Being on top of a ridge means we get strong winds and while the observing spot is well protected from prevailing wind from the SW those from the north hit it full on.

Cheers,
Steve

 

[Nigel G]

I'm going to give M1 a try while waiting for my main target to rise high enough.

Planning for a long one tonight.

[parallaxerr]

Clear as a bell but gusty here. 80 subs on M31 in the bag, this time at ISO 3200. Having learnt a little more about reading histograms etc, looks like the blue channel is being clipped at any lower ISO on the fuzzies, probably due to the semi-apo filter. Found out I do still have a slight alt limit in that the intervalometer plug connected to my Nikon contacts the mount, it bends out of the way but does offer some resistance so I've now re-targeted. 90° plug on order & M33 subs underway.

[Filroden]

I have 6 more lights to get before I will switch targets. My focus seems to have slipped a little in the last 30 minutes but hopefully not enough to impact the final image. Hopefully these extra 180 lights will reduce the noise in my NGC1333. Next target, maybe a quick set of subs on the Flaming Star Nebula as it's a little lower in the sky.

[happy-kat]

Where do I start... New battery is super, me I made a pear of it failed to align mount to polaris so failed in tracking wasted a good 40 minutes achieving nothing and a battery on camera that decided I'm not full I'm nearly empty! So I took star trails until it went flat. Saw several shooting stars and enjoyed the very dry air earlier which only got dew damp as it started to get less clear when I came in. This might force my hand to using my synscan v3 controller I have. Oh and going to switch back to my vintage 50mm as shows more stars for initial focus then the pancake lens. What a hobby! Talk about the 6 Ps

[Filroden]

Well, 60 lights on the Flaming Star Nebula but it's already rising too high for another run. But what do I see just clearing the fence. So now pointing at the HH + Flame. Both crystal clear in a single 45s sub!

[The Admiral]

Well it was reasonable here until about 9 tonight, when some fragments of cloud started to come in. I managed to get an hour and a half on M45. Good to get out again after so long.

Happy-kat, you have me confused! Surely you don't use Polaris to slign your Alt-Az?

Ian

[Stub Mandrel]

Totally unfair, I got cloud at 7:00pm :-(

Early next week looking good though...

[Nigel G]

78 on M1 so far , dumped 20+, still don't know the reason for such bad tracking at 30 second exposure. 

Sky's looking good here still. 

[Filroden]

My sky is willing, my body is not!

[happy-kat]

 

50 minutes ago, The Admiral said:

Happy-kat, you have me confused! Surely you don't use Polaris to slign your Alt-Az?

Ian

Well yes because I am only using it in tracking mode and following the mounts instructions. I haven't even got the synscan handset out of it's bag it came in, mainly because I don't see that much sky to pick good stars and I have had the mount track before so it it is my setup failing really.

[Filroden]

Well, one last sequence before bed...some M42 to finish the evening