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KevS

Anybody Playing Tonight?

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3 minutes ago, Gina said:

All packed up now and roof closed.  A good evening in spite of nearly full moon.  I'm much encouraged. 😀

Time for bed now so goodnight anyone still up and good luck to anyone still "playing".

Goodnight.  You must be very pleased with your progress.  The images are looking really good.

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2 minutes ago, geoflewis said:

Looking good Donal. The longest subs I've ever shot are my current 15m Ha. I couldn't face the prospect of shooting a bunch of 30m darks library.....!!

I should have been clearer.  It's 3 x 10m subs.  My autoguiding won't do 15m!

I don't think that I could do 30m darks either!!!

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Still going here doing 20 minute Ha subs of the Phantom nebula just keeping ahead of the Moon.

Dave

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Returning to the humidity thing, Dave, I've just been reading the datasheets and the sensor in mine is supposed to have an output of 4.07V (according to the ADC) at 0C for 100% humidity at a supply voltage of 5V.  It is actually reading 4.11V at a claimed supply voltage of 4.83V.

I suspect the ADC is correct about the supply voltage as it comes out of a 5V regulator and is connected to ground across a pair of schottky diodes, so I'm inclined to believe the 4.11V reading as well (I guess I could poke a meter in there at some point).  My suspicion is now definitely that the sensor itself has broken down.  I reckon it should have an output of nearer 3.93V with a 4.83V supply to give 100% humidity.

James

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Mines reading over the 100% again now.

It's got a Bosch BME280 sensor.

Dave

Edited by Davey-T

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Yes, mine is now reading over 108% and the output voltage is claimed to be 4.22V.  Ok, so we're not exactly at 0C (about -0.5C at the moment), but it shouldn't make that much difference according to the datasheet.

James

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Mines saying 115% now CO reckons it should be 84%.

Dave

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Sat24 shows cloud arriving soon so probably on my last sub for tonight.

Dave

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Cloud started to arrive, so I've just shut down. I've got 2 hours Ha on M82 which target was a spur of the moment decision, so I'm looking forward to see how that turns out. Hopefully I will add RGB data to it over the coming weeks....

Goodnight.

Edited by geoflewis

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Same here bits of cloud arriving got 16x20 minute Ha subs to play with.

Goodnight.

Dave

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Just covered scope up as completely cloudy now, managed 60+ 5 min HA subs of Jellyfish Nebula. 

Edited by AbsolutelyN
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It was too cold for me so I did some simple processing in free PhotoFiltre7.

Resize to 600, +contrast, - gamma, + sharpen.

The third image has been put through ImPPG.

I only did this to encourage Vin to try this for himself.

IMPORTANT Q: Is it considered "good form" to do this with other people's images?

Somebody once "redid" my best ever, handheld image of Mars.
I was stunned and delighted at all the detail he was able to bring out of my "fuzzy blob" of an original.
It instantly encouraged me to try processing my images for myself.

Q: Are my efforts on Vin's image actually an "improvement?"
Or only a matter of personal taste?

Thanks

vins moon.jpg

vins moon pf.jpg

 

 

vins  moon JPEG ImPPG.jpg

Edited by Rusted
Additional info.
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Wow, Rusted!  Those are amazing.  I cannot believe the last photo is the same as the first 😮 That's alchemy.  To your Q about is it good form, you'll get no complaints from me :) It's a bit like cover versions in music - there are covers that are better than the original.

Those kinds of improvement are exactly what I aspire to learn so all pointers v welcome.  Neither PhotoFiltre7 nor ImPPG work on Macs sadly, so I'm either going to go Pixinsight route, or will have to bite the bullet on a Windows laptop.  I'm a bit reluctant to get a new laptop b/c I'd then be lost in 2 OS instead of 1, and I've been slowly coming up the curve on EKOS in Mac, but if Pixinsight isn't suitable for solar that will probably settle things.  Yes, gamma is something I keep forgetting about (I did see it in ASICAP somewhere, but can't navigate myself around SiriL yet.  I open up SiriL and it talks about wavelets & Fourier transforms & Lucy Richardson...do I need to dust off my decades old maths textbooks?! 🧐)

Thanks again for the tweaking & showing what can be done.  I think a 45 day free trial of Pixinsight may be just what is needed for Christmas holidays.  ANd I still can't believe the 3rd photo!

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Hi Vin,

I'm glad you see it that way. :thumbsup:

There must be somebody here who can recommend a simple and free, image handling software for a Mac. Anybody?

The best free photo editors 2019 | TechRadar

Gamma is similar to Brightness but much more useful. I never [ever] use Brightness adjustment.

The ImPPG version was hardly touched. I had to reduce the initial sharpening effect just from opening the image.
It is all too easy to overdo Sharpening and produce ugly artefacts and an obviously unnatural effect. [The LG OLED TV look!] :wink2:
I consider the third image too close to borderline "overcooked" but wanted to show you had hidden detail and a nicely focused image.
All of which should encourage you to play with processing your own images.  

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Finally packed up this morning at 03:30, managed to get 3 hours on M81. That was of course after the very serious 3 hour senior moment forgetting to calibrate the guide scope to PHD on the wide field rig. More proof of concept and a bit rough and ready. 

Altair 72mmR  ED. 60 x 3 mins + bias, flats & darks. Canon 600d (unmodded) Processed in DSS and PS.

 

 

830690401_AltairM81_filtered.thumb.jpg.84657dd2da1150f9493ff64381c16b38.jpg

 

 

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54 minutes ago, Rusted said:

There must be somebody here who can recommend a simple and free, image handling software for a Mac. Anybody?

For simple image processing, I use GIMP in Linux - I think it works in Mac too.  It's a bit similar to PhotoShop but free.  For full blown image processing with all the "bells and whistles" and steep learning curve, I use PixInsight (not free but a free test period).

Edited by Gina
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Here's a quick stack and process of my 2 hours (8x15m) M82 Ha captured with the C14 last night.....

M82_Ha_IP.thumb.jpg.bf1ffec0735ebc44a97e9a4ade41ec09.jpg

It looks like the camera sensor has developed another bad column (bottom left centre) since I shot the darks library the back end of October, which is a pain as shooting a 900s darks library is not a quick task.

Also I initially focussed with L for Ha, but without any offset (doh), something I hadn't noticed until I checked focus again after a few subs, so I then changed autofocus to use the Ha filter which gave slightly improved focus. This stack includes everything, so I'll probably shoot a bunch more with Ha used as autofocus.

Nevertheless, I'm pleased to see the star burst regions ejecting either side of the galaxy, so I'll definitely continue with this project over the coming weeks/months.

Edited by geoflewis
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38 minutes ago, geoflewis said:

Here's a quick stack and process of my 2 hours (8x15m) M82 Ha captured with the C14 last night.....

M82_Ha_IP.thumb.jpg.bf1ffec0735ebc44a97e9a4ade41ec09.jpg

It looks like the camera sensor has developed another bad column (bottom left centre) since I shot the darks library the back end of October, which is a pain as shooting a 900s darks library is not a quick task.

Also I initially focussed with L for Ha, but without any offset (doh), something I hadn't noticed until I checked focus again after a few subs, so I then changed autofocus to use the Ha filter which gave slightly improved focus. This stack includes everything, so I'll probably shoot a bunch more with Ha used as autofocus.

Nevertheless, I'm pleased to see the star burst regions ejecting either side of the galaxy, so I'll definitely continue with this project over the coming weeks/months.

You've definitely got the faint "V" shape above the galaxy, and the rest has lovely sharp detail.  Just shows that there are still very useful things that you can do under a bright moon.

 

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Very few of the subs of the Horse's Head are any good.  There was advancing mist that I didn't see in the KStars preview (auto-stretched).  OTOH seems to be plenty of reasonable Heart and Soul subs I can stack so I'll probably have a go at that this afternoon.

Weather is attrocious - heavy rain and gales!  Dark too!!

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Not nice here either. My subs from last night are still on the telescope computer, and are staying there until I go out to sort out its network connection, Maybe tomorrow.

Now that's interesting. Had all kinds of problems with the network last night, but I've just managed to connect with RDP and transfer the files.

Edited by DaveS

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And here is a quick stack 'n' stretch of 12 x 10 min [NII] subs on the Witch's Broom from last night.

1546299332_2HoursN910mm.thumb.jpg.96c161c1b1588f099f9665be5b48e628.jpg

That spike *may* be from the 11kv overhead cable.

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Another thing I've noticed with my subs is that there is slight shift of position within the frame.  I think this may indicate less than perfect PA.  Of course this would normally be corrected by guiding with just a small rotation left but I'm not guiding.  One thing I could check next time we get some clear sky is PA which I can do by Drift Alignment.  Only trouble is that I will need to pop in and out to the mount to adjust it whilst imaging from indoors as I no longer have a working laptop.  (My proposed DIY fork mount for widefield will have remote PA control.)  Might be easier to provide guiding!  I'll think about it.

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Seems you are getting quite a decent amount of signal with that [NII] filter Dave.  Making me think.  Though I can get the Nitrogen image by subtracting 3nm from 5nm Ha, a separate 3nm [NII] filter would be better I've no doubt.  If my enthusiasm for astro imaging continues over the next year I may consider saving up for one.  Nearly all my NB imaging has been with the usual three filters - the only exception being Barnard's Loop etc. in Orion, where I definitely found [NII] signal.

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At the moment I'm wondering how much of that is genuine [NII] and how much is residual H-alpha that's creeping in through the overlap between the lines. Maybe a careful subtraction of one from the other might give me some idea.

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Yes, I wondered if some of that was Ha creeping through.  I guess 5nm - 3nm Ha may give a truer [NII] signal.  The problem with subtracting image data is that the images really need taken at the same time and with matching optics and cameras.  I can do that with WF and lenses but I don't have pairs of telescopes other than ST80s and Evostar ED80 Pros.  Maybe it's time I brought these into service again.  I have two ASI 1600MM-Cool cameras.  I get the feeling I may not be making best use of my equipment.  That's in addition to lack of use due to the weather.

My experience to date is that I frequently get very little signal with the 3nm [SII] filter and a using a different set of three wavebands may be better for 3 colour images from NB.

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