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Very Frustrated-please process this data


Rodd

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I use to post data sets in the summer for those folks in sub polar climates to give them something to process in the twilit weeks of the midnight sun.  I had envisioned a reciprocity of sharing, which would have help during times of poor weather.  Regretfully, that eventuality did not come to pass.   I offer this data now for a much more important reason.  I have grown tired of beating my head against an iron door, and I have reached a point where I must decide if this hobby is for me.  I am tired of collecting 25-30 hours (or more) of data over weeks of time, then spending untold hours processing and reprocessing, only to be thoroughly dissatisfied with the results.  I like to blame the sky, but perhaps the real reason my images are inferior is because of a lack of processing ability.  Perhaps its both.  Even when I think the sessions have gone well, and the stacks look good, the resulting image leaves me frustrated.  The best way I can think of determining if the problem lies with me or the data, is for accomplished imagers to process the data.  I realize judging images is in large part based on personal preference, so this is not meant to be a contest.  There are no rules at all other than to process the data and post it here.  After that, you may do with it what you wish.  Opinions, theories, tips, etc., of course,  are welcome.  This will help me with my decision.  I have to make a serious change, either sell everything and get out, or sell most things and purchase a remote spot at a remote hosting facility with what remains.  A third option would be to forgo 30 hour data sets for 5 hour data sets, and process images in a catalogue type way-but I would have a hard time with this approach. There is no question the sky impacts the quality of my images.  But that is true for everyone that does not shoot from Bortle 1/2.  The question is, can processing acumen make up for the sky conditions to enough of an extent for me to once again find pleasure in this endeavor.   Many of you may call be crazy and ask "what don't you like about your pictures?", not understanding my concern.  I remind these folks that image assessment is a personal thing,  As U.S. Supreme Court Justice Potter Stewart remarked about pornography "I can't use words to describe it, but I know it when I see it", so too I say about defining a really good astrophotograph.  I feel it in my bones.  Of course, I can list a number of parameters that support the contention, but those details are checked after the fact.  A good image  rings " I AM AMAZING" in my head and later I verify its truth.  With my images, I must try and refute a nagging voice whispering in my ear that it is sub  par.  And over time, I come to agree with it.  At first glance, the image may look decent, but give it a few days, and it becomes a nose-wrinkler.  Much like a house I suppose.  You love it when you buy it, but after 20 years you can't wait to get out.  The company that lets you sleep on a mattress for 30 days before deciding you want to keep it is genius!

The stacks are fully calibrated and registered.  I have included my most resent version of the image as reference--it is a reprocess of the image I recently posted as "M101 HaLRGB" .  No amount of reprocessing has helped much.

Thank you in advance, and have fun.  I hope your images come out amazingly--for then there would yet be hope.  

r170.fit

g116.fit

b123.fit

superL-471.fit   ( made from low FWHM subs), you may want to try the pure luminance as well  l400.fit , or a super-luminance made with all LRGB subs SuperL-LRGB.fit  Which is better?

h90.fit

zzzz3b.thumb.jpg.34e3fc40734e3c8160c1d7549156841e.jpg

 

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Wouldn't call myself an expert, but processed the dataset anyway. Cant capture anything at the moment anyway so might as well practice.

Some questions for the set, how bad is your light pollution? My initial guess from the data is that there is a fair bit of it, but its not the end of the world since the stacks still contain all the good stuff. But for almost 30 hours it does look not that deep so i am guessing light pollution is a major issue. Apologies, have to be the bearer of bad news but looks like calibration has not worked perfectly as some dust motes remain so at least flats have something to improve. These are not at all apparent though and only appear after hard stretching. Not the end of the world i think, but something to improve if you want to.

I processed an L-RGB image out of the stacks. I used the l400 named file for luminance since the fwhm difference is not too big compared to the sharper one so i think not worth loosing data for that. Did not include the Ha file as im still learning how to do that properly and cant land on a "right" looking result yet, so dont want to muddy the waters with my poor attempts. But below is my attempt for now. Usually i process an image, delete the intermediate files and sit on it for at least a day while occasionally looking at it. I cant recall if i ever used the first day attempt as the final image, probably not since the first result is often more wrong than right. Often it is attempt number 5 or more that gets posted. No such thing as too much reprocessing! Focus on this image was to show all the faint arms if possible and it certainly is.

RoddM101-lrgb-blurxt-stretchcopy3.thumb.jpg.eeb5997d3e96f5b7d618587af24b0a33.jpg

And the dust motes i found below. Generally the image edges also took a dark turn while stretching, which may indicate imperfect flats, or imperfect background extraction (which often happens because of imperfect flats). Personally i would try to solve this issue, up to you to decide whether its worth taking action on.

RoddM101-lrgb-blurxt-stretchcopy3dust.thumb.jpg.8a5a87c107fefdc5f0d2000119db8764.jpg

Then ill briefly go over what i did to the image.

First, gave all the files a crop, binned x3 based on the fwhm values and my preferences (probably should have binned x2, more later). Then gave them a background extraction in Siril with the excellent tool in it. The background in these stacks is very challenging, and i think you might be loosing the faint stuff already at this stage if the background extraction part goes wrong. The situation is challenging because the image has almost no background to speak of, all except 2 corners of the image contain faint spiral arms of M101 and if background samplers are placed here the result is sure to be ruined.

Did L-RGB combination in PixInsight after linear fitting the RGB files to the luminance one. Ran SPCC for colour calibration and BlurXT with automatic PSF and nonstellar set to 0.8. Seemed to have worked ok without any obvious BlurXT caused issues. Then saved the file and opened it in Siril again, because i like the user interface and stretching tools better than PI. Gave the file an Asinh stretch with a power of 1000 and some blackpoint adjustment to bring down the levels. Finished this stage with a histogram transformation for an "almost finished" image that i exported to Photoshop.

At this point the file looked like this, an almost finished image and a sort of template for the dozen attempts that follow:

RoddM101-lrgb-blurxt-stretchmidpoint.thumb.jpg.46373b76c043185e3d095d048c972d99.jpg

The Photoshop phase of processing sees almost all of the work. Fiddling with various tools and sliders to no end until the image either fails in a death by a thousand cuts fashion or becomes what i initially had in mind one brick at a time. I used a very simple background lift with the shadows and highlights tool to uncover some of the fainter spiral arms while still controlling the core. Love that tool, couldn't be simpler to use and works great for things like this and i dont really hear anyone mention that online. Sharpening with smart sharpen applied only on high SNR regions with either the color range tool, or lasso+feather+copypaste as new layer and adjust to taste. Took many wrong turns on the way and i think i went too far with the sharpening as is almost always the case. This is usually something the finalversion_copy_adjust_mk2.4_usethis_jpeg file fixes a dozen attempts down the line if i figure how to not make the same mistakes (doesn't always happen).

On the binning, i found myself looking at the image almost exclusively past 100% zoom while processing and applying sharpening. Usually this means binning went too far and i could have used the image at a higher resolution and i think here is where i made the first mistake.

Some comments on your process; It is left very dark in the background, which makes it difficult or impossible to observe the faintest spiral parts because they are just a few levels more than the background. Maybe you could ease on the levels and leave them a bit higher? I think i recall you mentioning the background being difficult on many images, which i agree this one was challenging. So here i will recommend using the background extractor in Siril (or GraXpert, a standalone app of the same tool basically) with manually placed samplers. Here you have to be careful not to place a single sampler on a star or on a faint spiral arm. Will likely take a few tries as you cant see the arms before the gradients are removed.

PS, as i write this comment i am already disliking the processed image i attached here. So i understand your frustration!

Processing is an uphill battle for sure.

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13 hours ago, ONIKKINEN said:

flats have something to improve.

Not sure what can be done here.  I hate flats.  I use a flat panel and flats very rarely are perfect.  I shoot flats every night and if I change filters in a night, I shoot flats for every filter right after use, and still, they don't work much of the time. I do this because If I don't, flats will NOT work.  This is a long story and this forum is replete with my angst over flats not working due to dust particles moving night to night, or the filter wheel not aligning perfectly night to night (2 different cameras).  Flat brightness is good, flats look perfect.  So not much can be done about this.  I did not see the motes you point out-which stack are they in? Not only do I have light pollution, but transparency is often poor due to haze, moisture (whatever impairs transparency).  I think this is the source of the background "fog" in the image.  It might not be gradients, per se, that is why DBE  doesn't work so well (I have tried dozens of times using multiple iterations).  DBE in PI is considered a very good background extraction tool.  Even anti-PI-ers use it.  

I disagree about there not being much background. It doesn't look like there is, but much of that is the foggy aspect of the background--which is not faint extensions.  But I will say, it was very hard to compare due to your unusual orientation.  I downloaded your image and re-oriented it to match the original.  You DID manage to pull out faint extensions where they exist, but the background looks so hazy.  The odd thing is the numbers are not that high .  In PI they are .08-.09, which is just a bit high.  I try for .05-.07.  The strange thing is, even at .01 or .02, the fog remains, and the background is grainy--even with near 30 hours of data.  Bottom line is, it doesn't look like space, for what ever reason.  That is why my level of stretch is not as much as yours-because the background can't support it.  But if I waited for perfect nights, I would never finish an image.  This is why i am frustrated and ready to pack it in.  I just get [removed word] off all the time--not having fun.  And as George at Astro-Physics says--"as long as your having fun"....I'm not.

Yes the data should be binned 3, but I have mixed feelings about binning.  First off, the FWHM of this data is about 2.2-2.4".  It is hard for me to believe that seeing at my location is better than this (its ALWAYS recorded as poor with some sporadic nights being average.  I use the C11 to shoot galaxies for the scale--to get close in.  Bin 2 still allows a full resolution zoom--though smaller than bin 1.  Bin 3 does not.  If I always have to bin 3 or higher, then I might as well not be imaging at this focal length at all.  It means my sky just can't handle it.  

But I must beg off now--I am getting aggravated.  Except for the orientation (strange choice!) your galaxy looks very nice.  The background is another story.  If you can find a way to produce the galaxy with a "normal" background:, its would be a winner. I did not like your galaxy on my phone--but on the computer I see its merits.  That is another aspect of this hobby (obsession) that I absolutely hate--images look different on every screen.  Well--my images.  Good images look good on all screens.  Mine never do.

My judgement, based on your image, is that both my processing AND my sky suck.  I am afraid the train is still hurtling toward either a LONG hiatus, or the end of the line (at high speed).  Thanks for your input.  

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I think you're being too critical, your original image doesn't look that bad at all and I would be happy with that. Maybe in my opinion just raise the black level of the background a little bit, images don't look very "natural" when the space is very black, this will also help a little with faint nebulosity.

I understand your frustration with long integration though, my last one was over 24 hours and the end result wasn't very good at all (well compared to what others were doing), but at the time I liked it but I said never again. Now I usually only do around 5-10 hours which is sacrilege, but as long as I have the target in full I'm usually happy with it. So the difference is I've adjusted my expectations. I've also looked into faster systems which helps but not everyone has the means to.

I always tend to approximate AP is approx 20-30% image acquisition, the balance is post processing. You cannot get the results you want without the latter. I personally don't even use PI, I'm sure if I did I would reap some benefit but it's a personal choice for me, I'd rather do most of the work manually as it can be applied to other image editing. But as mentioned your original image is good, so I wouldn't fret too much.

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3 hours ago, Elp said:

But as mentioned your original image is good, so I wouldn't fret too much.

Thanks-its still frustrating.  If I got more clear nights it wouldn't matter.  But when I lose 4 hours of data because the flats fail, that means weeks of extra time.  Spending a month making an image that is.......mediocre is trying.  That is why I need to know how much is my processing and how much is the sky/equipment.  One can be fixed, the other can't.  My goal with the image was pulling out details in the galaxy, which I think I did fairly well.  But my image looks nothing like most others--and I overstretched at first too trying to pull out faint stuff.  One of my tenants is to not push the data past what it can support.   For example--noise control is not necessary if one stretches only up to the noise threshold.  In poor sky, or with little data, this makes for a very dim image.  But I like the concept and it makes me not stretch beyond what the background can support. That is why my images are dark--I just can't stand a mottled, salt and pepper, or irregular backgrounds.  It doesn't help that my processing computer looks totally different than other screens--even itself when viewing on a forum.  When in PI, my background looks ok--but posted, it looks washed out and too bright--so I drop the black point. In my image, some spots are too dark, but many are not--its irregular.  That is the quality of my sky.  I am getting tired of it.

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The issue with monitors and screens in general is that they're all different, even if using the same panel. Unless you professionally colour calibrate them you'll never get a "finished" look, most screens also don't support a wide colour gamut, especially within specific colour spaces, there's a reason professional monitors and video monitors cost so much. I've found when processing AP, do it with the lights off at night helps a lot, you just don't have the same perceived contrast when you've got a backlight or extra light around you affecting your vision and what you see on screen. Adjusting your screen gamma settings will also help.

Getting good flats will also even the brightness across the field removing vignette, it's one of the reasons for doing it. I have issues with it still, but the flats applied image is always better than the one without.

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11 minutes ago, Elp said:

but the flats applied image is always better than the one without.

With the C11 I pick up all the dust bunnies.  With the FSQ I get none.  Strange.  Must be focal length related.  With FSQ its all illumination correction as you say.  With longer focal lengths, I can't do without flats--no way.  Dust bunnies ruin images.  I always use them.  But they are a PITA.  My histogram for flats is exactly at 1/3, I have tried 1/4, 2/3...you name it.  Still, they miss things.  

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What light source for flats and camera are you using? I've found my flats are a bit more consistent since I started using acrylic sheets (around 4 layered) to dim the light from my flat panel significantly so that they're at least 2 seconds (usually OSC) to 10 seconds (narrowband) long per flat image.

There is also a process I sometimes use, I make my flats myself (synthetic flat) using the RGB stack, a few minor processes and then image subtraction. I can try it on your above image and see if it helps.

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4 minutes ago, Elp said:

What light source for flats and camera are you using? I've found my flats are a bit more consistent since I started using acrylic sheets (around 4 layered) to dim the light from my flat panel significantly so that they're at least 2 seconds (usually OSC) to 10 seconds (narrowband) long per flat image.

There is also a process I sometimes use, I make my flats myself (synthetic flat) using the RGB stack, a few minor processes and then image subtraction. I can try it on your above image and see if it helps.

My flat panel works pretty well (it seems).  The only problem is Ha--which can require 20 sec flats (or longer).  But I rarely have trouble with Ha.  I use 100 flats per master flat, so even very short ones tend to make very noise free master flats.  I have read some people think short flats are better and some think longer flats are better.  I looked at the master stacks for this image under boosted STF stretch in linear state and don't see the bunnies that were pointed out.   

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22 hours ago, ONIKKINEN said:

Processing is an uphill battle for sure.

Well--I had a go at reprocessing (for the umpteenth time).  Thanks to you, I think the image is improved.  The background is fairly consistent, though the values are a tad high.  I think the darkest area is .06--which is just about right.  I wanted tp ere a bit high this time.  I have maintained the inner details and spiral arm structure--in fact I think its improved.  But the image STILL looks nothing like yours--both from a faint extension perspective, as well as an overall look.  Its hard to explain, but your image looks like a huge galaxy  at some distance, while mine looks closer with a smaller scale.  The details on yours look like they are really small way far away, and the details on mine look like they are much closer.  Kind of like yours looks like a 100,000 light year galaxy, and line looks like a 10 foot model of a galaxy.  Maybe I have been looking at the screen too long.  Anyway--I think the consensus would be that the image is improved.  Sop thank you.  You may have salvaged my career from the refuse pile--or at least bought me some time.  I am again looking forward to tonight....at least until I look at this image in the morning, at which time I may be headed for the land fill again!

 

 

 

Image10e5c2.thumb.jpg.0bcc11600ea8a667ba6086e9c3a54b2a.jpg

Edited by Rodd
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Well first of all, you're far too self critical Rodd! Your image might not be what you'd envisioned, but there is some lovely crisp detail and the colour balance you've got presents very well indeed, in my opinion. 

I had a quick look at the pure luminance stack, and as I also had a stack of a similar integration time from my own attempt at M101, I've made a comparison between the two. 

I would agree with the above re: flats, there are what appear to be residuals of dust motes visible when the image is stretched hard enough to bring the fainter areas into visibility. The image also isn't quite flat - a couple of the corners and the two short edges are darker. Not significantly, but it becomes apparent after a stretch. 

I couldn't really get a good background model from DBE for your image - I think I probably modelled the gradient incorrectly on the initial iteration and in the end I've made a bit of a hash of it by running multiple iterations (there are quite visible brighter areas, particularly in the bottom right - maybe I'll try again later). For the purposes of the comparison though, it's good enough I think.

I don't know what your pixel scale was, but I registered yours to mine (at 1.74"/pixel) with StarAlignment's default rescaling option, then cropped to match FOV, DBE, and some denoising. I used a couple iterations of GHS to stretch. The first GHS focused on bringing forwards the fainter regions, and as this tends to leave a rather flat, low-contrast image, a second GHS boosted the brighter regions a bit (for a finished image, I would usually spend a good long while dialling the best settings in, followed by some custom curves and other things like LHE, so this was a rather rough and ready go at it). I tried to match the stretches visually as best I could, although I was doing it on a laptop, not my usual processing machine.

M101Comparison1.thumb.jpg.a13c9a08cd50aa8ea506df2c903be5b7.jpg

 Close up of a faint arm:

M101Comparison2.thumb.jpg.b65385ef08adca40eee0bb000e3b22c2.jpg

To my eye, all the same detail is there at similar brightness levels, and background is nice and smooth (DBE induced issues around the edges notwithstanding). I think you're just going to have to accept that if it's the faint stuff you want, noise reduction is going to be required to allow you to bring it out.

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1 hour ago, Rodd said:

Well--I had a go at reprocessing (for the umpteenth time).  Thanks to you, I think the image is improved.  The background is fairly consistent, though the values are a tad high.  I think the darkest area is .06--which is just about right.  I wanted tp ere a bit high this time.  I have maintained the inner details and spiral arm structure--in fact I think its improved.  But the image STILL looks nothing like yours--both from a faint extension perspective, as well as an overall look.  Its hard to explain, but your image looks like a huge galaxy  at some distance, while mine looks closer with a smaller scale.  The details on yours look like they are really small way far away, and the details on mine look like they are much closer.  Kind of like yours looks like a 100,000 light year galaxy, and line looks like a 10 foot model of a galaxy.  Maybe I have been looking at the screen too long.  Anyway--I think the consensus would be that the image is improved.  Sop thank you.  You may have salvaged my career from the refuse pile--or at least bought me some time.  I am again looking forward to tonight....at least until I look at this image in the morning, at which time I may be headed for the land fill again!

 

 

 

Image10e5c2.thumb.jpg.0bcc11600ea8a667ba6086e9c3a54b2a.jpg

I think the different looking "scales" in our images is the difference in how the dynamic range is presented. I have crushed the shadows and midpoints pretty much together in order to show the faint parts better. That creates a very flat looking image where all the detail appears close to the same brightness as if it were a distant background galaxy with an even brightness, which is not always what you want (and a matter of preference anyway). I think this image of yours is really nice, an improvement over the initial for sure. You have very nice colours where it matters, and the faint parts are much better seen. How well you want to show them is a matter of taste, so i dont think there is a right answer.

If you want to compare our images in a more raw state i am attaching the LRGB stack i used below. If there is a difference in the background of our linear images then it should be easier to see without fancy processing in the way. The tool in Siril is destructive to actual data if applied incorrectly, and even slightly when applied correctly. But it is fantastic for bruteforce gradient removal and in my opinion much better than DBE that i would describe as more careful with the data.

RoddM101-lrgb-blurxt.fit

Binned x3, then background extracted in Siril for the individual mono files, LRGB combined in PI, SPCC and BlurXT applied.

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5 hours ago, Rodd said:

With the FSQ I get none.  Strange.  Must be focal length related

Not necessarily strange at all. With a slower scope, dust bunnies that are further away from the sensor can still be picked up. Dust on the camera front glass is picked up by most telescopes, but dust on filters only by slow ones.

Btw, I processed your image in PI and find it quite a pleasure to work with. The L has great detail. The colour data was a bit "thinner". I don't know if you should adjust the exposure time or camera gain for RGB. Anyway, here's my result.

On my screen, the background is still uneven, but otoh, it seems that my screen is very unforgiving in that respect. I've seen a lot worse in images processed by professionals. All in all, great data to work with.

Rodd_M101_LHaRGB.thumb.jpg.640dc1fea7a44f807ee739db950399b5.jpg

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1 hour ago, ONIKKINEN said:

You have very nice colours where it matters

But I botched the red point.  I think this is better and the version I will sit on for a time.  Though I see wim produced a red one as well.  

 

z4a.thumb.jpg.0e709939953d7c2a2c3a8053a5c915b1.jpg

Edited by Rodd
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43 minutes ago, wimvb said:

The colour data was a bit "thinner". I don't know if you should adjust the exposure time or camera gain for RGB.

I think I shot color in poor transparency.  But it was clear and no Moon, so I said what the heck.  I can't afford to miss clear nights.  I like your image (perhaps a tad red?  That's what mine looked like and I reduced it (see my last post).  But I might be wrong.  This galaxy is a slippery one

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2 hours ago, The Lazy Astronomer said:

To my eye, all the same detail is there at similar brightness levels, and background is nice and smooth (DBE induced issues around the edges notwithstanding). I think you're just going to have to accept that if it's the faint stuff you want, noise reduction is going to be required to allow you to bring it out.

I don't follow 100%  These two mono images are from where?  AHH I see the label--one is mine--processed by you.  I guess it is me after all--they look almost identical.  Not bad data I guess.  Sky is a bit bright.  Thanks for the input.  I am slowly pulling myself out of the hole.  I was sucked in to quicksand!

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1 hour ago, wimvb said:

Btw, the background of the L400 image is (after DBE) very flat. here is the superstretched inverted image.

l400_clone1.thumb.jpg.9aa6e15e754a31a85e33ff7b743e43dc.jpg

Ah, much flatter than my bodge job, but I think I still see a sort of bordering effect - in the inverted image above, a lighter area around the outside (I'm assuming stacking artifacts), then a thicker, darker border, most visible along the bottom and right hand edges.

1 hour ago, Rodd said:

I don't follow 100%  These two mono images are from where?  AHH I see the label--one is mine--processed by you.  I guess it is me after all--they look almost identical.  Not bad data I guess.  Sky is a bit bright.  Thanks for the input.  I am slowly pulling myself out of the hole.  I was sucked in to quicksand!

Oh yeah, sorry, I meant to specify which was which. It actually surprised me (although I guess it shouldn't have, really) just how similar they do appear to be. 

Background-wise, l usually go for a value in the region of 0.08 - 0.09, which is a bit brighter than the values you've mentioned above, so personal preference, I guess. That said, I think the values for what I've posted are more like 0.10 - 0.11ish, so they actually are a little bright.

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@Rodd which program do you use for stacking? If PI, consider usong the autocrop function of wbpp. As @The Lazy Astronomer noted, there is a soft edge in your images that may be caused by stacking. Autocrop in wbpp will deal with that.

7 hours ago, Rodd said:

I think I shot color in poor transparency

That can explain it. I always blink subs before stacking and remove those that are too "thin", ie when I see a loss in contrast between the object and the background. I've at several occasions, thrown away whole nights worth of data because of lack of contrast. Such is AP in temperate climates.

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19 hours ago, wimvb said:

@Rodd which program do you use for stacking? If PI, consider usong the autocrop function of wbpp. As @The Lazy Astronomer noted, there is a soft edge in your images that may be caused by stacking. Autocrop in wbpp will deal with that.

That can explain it. I always blink subs before stacking and remove those that are too "thin", ie when I see a loss in contrast between the object and the background. I've at several occasions, thrown away whole nights worth of data because of lack of contrast. Such is AP in temperate climates.

Like last night.  A big waste. It was supposed to be clear but it never cleared up.  I have never used the wbpp for anything but calibration.  What do you mean by soft edge?

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On 14/05/2023 at 21:28, Rodd said:

I use to post data sets in the summer for those folks in sub polar climates to give them something to process in the twilit weeks of the midnight sun.  I had envisioned a reciprocity of sharing, which would have help during times of poor weather.  Regretfully, that eventuality did not come to pass.   I offer this data now for a much more important reason.  I have grown tired of beating my head against an iron door, and I have reached a point where I must decide if this hobby is for me.  I am tired of collecting 25-30 hours (or more) of data over weeks of time, then spending untold hours processing and reprocessing, only to be thoroughly dissatisfied with the results.  I like to blame the sky, but perhaps the real reason my images are inferior is because of a lack of processing ability.  Perhaps its both.  Even when I think the sessions have gone well, and the stacks look good, the resulting image leaves me frustrated.  The best way I can think of determining if the problem lies with me or the data, is for accomplished imagers to process the data.  I realize judging images is in large part based on personal preference, so this is not meant to be a contest.  There are no rules at all other than to process the data and post it here.  After that, you may do with it what you wish.  Opinions, theories, tips, etc., of course,  are welcome.  This will help me with my decision.  I have to make a serious change, either sell everything and get out, or sell most things and purchase a remote spot at a remote hosting facility with what remains.  A third option would be to forgo 30 hour data sets for 5 hour data sets, and process images in a catalogue type way-but I would have a hard time with this approach. There is no question the sky impacts the quality of my images.  But that is true for everyone that does not shoot from Bortle 1/2.  The question is, can processing acumen make up for the sky conditions to enough of an extent for me to once again find pleasure in this endeavor.   Many of you may call be crazy and ask "what don't you like about your pictures?", not understanding my concern.  I remind these folks that image assessment is a personal thing,  As U.S. Supreme Court Justice Potter Stewart remarked about pornography "I can't use words to describe it, but I know it when I see it", so too I say about defining a really good astrophotograph.  I feel it in my bones.  Of course, I can list a number of parameters that support the contention, but those details are checked after the fact.  A good image  rings " I AM AMAZING" in my head and later I verify its truth.  With my images, I must try and refute a nagging voice whispering in my ear that it is sub  par.  And over time, I come to agree with it.  At first glance, the image may look decent, but give it a few days, and it becomes a nose-wrinkler.  Much like a house I suppose.  You love it when you buy it, but after 20 years you can't wait to get out.  The company that lets you sleep on a mattress for 30 days before deciding you want to keep it is genius!

The stacks are fully calibrated and registered.  I have included my most resent version of the image as reference--it is a reprocess of the image I recently posted as "M101 HaLRGB" .  No amount of reprocessing has helped much.

Thank you in advance, and have fun.  I hope your images come out amazingly--for then there would yet be hope.  

r170.fit 62.76 MB · 9 downloads

g116.fit 62.72 MB · 15 downloads

b123.fit 62.73 MB · 9 downloads

superL-471.fit   ( made from low FWHM subs), you may want to try the pure luminance as well  l400.fit , or a super-luminance made with all LRGB subs SuperL-LRGB.fit  Which is better?

h90.fit 62.73 MB · 7 downloads

zzzz3b.thumb.jpg.34e3fc40734e3c8160c1d7549156841e.jpg

 

I think you are being to hard on your self. It is a wonderful image. With help in the forums you can improve things.

I image from sea level, average seeing, moisture, few clear nights, bortle 5.

Even so, I started imaging 4 years ago with a 12 inch Meade sct. I struggled for a year with it. I was getting a soft background, focusing problems, flat problems from time to time. Long story short, I gave up on the SCT. To much hassle with poor results.

Then I went the refractor route. I admit I went over board and got a CFF 8 inch f 6.5 apo because I could afford it, but the fact is, a refractor, what ever it's size, is much easier to work with. The background was much better, no flat problems, no focusing problems, no collimation problems, no mirror shift.

Since I got the refractor and ditched the SCT, I actually started enjoying the hobby.

For flats and imaging I use Prism v11. It figures the exposure time automatically, I simply tell it how many flats I want and where to save them. I take flats after ever session, to be safe.

So for 3 years I've been enjoying the hobby even in my poor sea level conditions.

You can search my image here on stargazerslounge forum: Abell 2218.

I've gathered 100 hours useful data for the Luminance and currently I am at 20 h for green filter.

The image posted has minimal processing because I am learning as I go.

So my advice...cheer up, ditch the SCT, get a refractor or a better suited for imaging reflector. Keep the SCT for planets.

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15 hours ago, dan_adi said:

I think you are being to hard on your self. It is a wonderful image. With help in the forums you can improve things.

I image from sea level, average seeing, moisture, few clear nights, bortle 5.

Even so, I started imaging 4 years ago with a 12 inch Meade sct. I struggled for a year with it. I was getting a soft background, focusing problems, flat problems from time to time. Long story short, I gave up on the SCT. To much hassle with poor results.

Then I went the refractor route. I admit I went over board and got a CFF 8 inch f 6.5 apo because I could afford it, but the fact is, a refractor, what ever it's size, is much easier to work with. The background was much better, no flat problems, no focusing problems, no collimation problems, no mirror shift.

Since I got the refractor and ditched the SCT, I actually started enjoying the hobby.

For flats and imaging I use Prism v11. It figures the exposure time automatically, I simply tell it how many flats I want and where to save them. I take flats after ever session, to be safe.

So for 3 years I've been enjoying the hobby even in my poor sea level conditions.

You can search my image here on stargazerslounge forum: Abell 2218.

I've gathered 100 hours useful data for the Luminance and currently I am at 20 h for green filter.

The image posted has minimal processing because I am learning as I go.

So my advice...cheer up, ditch the SCT, get a refractor or a better suited for imaging reflector. Keep the SCT for planets.

I have 3 refractors.  I use the C11 Edge for galaxies and PNs. When the nebulae come around again I will switch to the fsq or TOA.   Galaxies need aperture.  I like the resolution and fine details

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I've been using my C6 more I find. Having the choice of imaging at three totally different focal lengths is useful. As mentioned the resolution difference is quite marked, even if my apo is sharper though smaller aperture and takes a hit on resolution in comparison. I can only imagine how much difference a C11 makes.

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1 hour ago, Elp said:

I've been using my C6 more I find. Having the choice of imaging at three totally different focal lengths is useful. As mentioned the resolution difference is quite marked, even if my apo is sharper though smaller aperture and takes a hit on resolution in comparison. I can only imagine how much difference a C11 makes.

It’s amazing. Really. Binned 2x2 With the .7x reducer  and the asi 1600, it has about the same pixel scale and the same focal ratio as the TOA 130.  In fact the c11 is F7 and the TOA is F 7.7.  So the extra aperture translates to speed.  I haven’t found the TOAs sweet spot yet.  The fsq 106 is great gif nebulae and large targets.  The TOA is in no man’s land, sort of.  

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