Rodd

Yeah, I guess more data would not be that effective. maybe I could shoot it with the FSQ and register the data to this and combine just in teh faintb spiral arm--unless teh act of registering to a data set of smaller pixel scale erases any gain in speed afforded by the FSQ at F3.

I have eliminated the filter positioning as I always shoot flats before any filter change--so the filter wheel is removed from the equation. Not sure I understand about different light paths. I will try and collect flats at different elevations, including horizontal, though it wont be easy to devise a way.

maybe I should collect a bunch more lum on this target and bring these arms out more strongly

Wiow--thanks Vlad. Your processing skills are amazing. More afirmation that its me and not the data. That is encouraging. Now I ust have to fix the flats issue I am having and I will be on track. There is another thread of mine....at first thought it was mirror flop, but now suspecting the focuser. Not sure though

LP is not the only issue--transparency nis key. Sometimes I can hardly see constellations, like Ursa Major. Soupy sky. The differece between those nights and dark nights where the stars are clear as day is huge. I dont get those types of nights very often.

I use noise control--but the smallest amount I can get away with. I use noise Xterminator. Its not a panacea. No doubt I could learn to use it more effectively. As far as a new scope.......I have an FSQ 106, TOA 130 and an NP101is. None are as good on galaxies as the C11Edge. I got the C11Edge for galaxies and planatary/lunar. I am not after widefiled with this. My sky is not good enough for a OSC I have been told--so a RASA is out. Besides, major gear changes would require selling stuff first. Besides 2, yall have shown me that the problem is me, not the data, so my efforts would be better spent on my skill than starting over with a new scope. If I could buy a new scope, I would be very interested in a RiFast scope (long focal length and short focal ratio). A new scope is not in the cards. I need a new camera (2600). maybe someday. Bottom line, I would be willing to bet, as you have shown me, that my gear is good enough to render nice images. I think the last thing I need to do is change scopes.

I'll have to try that. Thanks. Then again, I jusy checked, I am using ASiimg--not air.

It is good to be recalibrated, so to speak. In general, you are right. I suppose it depends on how one looks at it. For whatever reason I have decided that it is important for me to do astro photography. I have wanted to since 7th grade (50 years ago!). I see amazing images that flip the switch, ring the bell, clobber the noggin, what ever phrase works for you. Long have I suspected that "I am missing something". I do xy and z and you do x y and z and the results couldnt be more different. In the end, hedonism drives me. Why am I so bent on achieveing the "perfect" image....becuase it feels good. Its amazing that we can do this at all, really, and to see an image of a nebula or galaxy that is clear and deep (without being overrly exposed in bright areas), and realistic looking, and far better than the images in the astronomy books I wore out when I was a kid, does something for me...to me. I said I want, "must" do that. So I spend an ungodly amount of money on gear, spend an ungodly amount of time collecting data, and an ungodly amount of time porocessing the data.....only to have the nebula look green? Not acceptable....so I fixed that by spening an ungodly amount of time figuring out what to do. At this point, there is only one course of action available to me. Well, two...sell everything and find another obsession, or see it through to the end. I guess I have the mindset of "if its worth doing, its worth doing perfectly". The feeling I get when I look at a truly great image is akin to what a moth must feel about a flame....I simply must make my image as good as the data can be rendered. To truly find that line between ones skill and what the data can be without artifact or imballance. I know.........GET A LIFE, right?

I dont think its the panel, or even mirror flop at this point. All knowing minds point to the focuser. Besides, if the panel was 10 feet away, or 5 or wahtever, the duration of my Ha and SII flats would go from 20 sec to minutes!

I use ASair too--though an older version I think. It does not support dither, and I have never seen a flat calculator. It doesnt take me more than a few secons to manually get the histogram where it should be. A couple flats. I find that SII and Ha can take 30 sec to achieve a good flat--and that is being generous becuase until recently, I was under the impression that 1/4 was good. Now that folks have steered me to the understanding that 2/3 is better--it would take more than 60 sec to shoot a good Ha or SII flat. With the FSQ sky flats work amazingly well. There are no dust motes to speak of so its just illumin ation. A cloudless sky just before dark works like a dream. Not with the C11 though--I need a diffuser (fabric over the objective). That is a pain to do--especially when time is pressing, which is the case for sky flats. There is a very short window between too bright and too dark

The C11 is a bit different. I had a stepper motor attached to the stock focuser and I experiemced serious flop. It was most apparent when trying to focus during lunar/planetary imaging. I would have to wait until the image returned to a stable position before analysing focus. I made the change to a back end focuser mostly for that reason--I never considered how it coukld impact calibration. I wish I could afford a 10" refractor. Then I would be in Elysium

Crude? You nailed teh colors! It looks.....almost blike a photograph! It would be possible to do as you suggest, though it is on the heavy side. At this point, it would be verifying something we already know--dust motes move. I think the first place to look, after everything everyone has said, is the focuser. The fact that it doesnt happen all the time could be good news, or bad. ohn Hayes seems to think that a draw tube focuser on a EDGE is not viable, for a couple of reasons. 1) this problem, and 2) the sensor does not remain precisely at 156.5. Granted, focus travel is very small-fractions of a milimeter, but the principoal is not as sound as something like an Optec. Unfortunately Optrecs cost over $2,000. Not in the cards at this time. I have been thinking about selling everything and starting over and building a "perfect" system. If I lived in Bortle 1/2 and frequently had 5/5 seeing, I would consider it more seriously. Robo scope might be the answer--it only costs about $1,600/year to get all data from 3 different scopoes. $900/year for one scope. I would be flooded with data if I had 3 scopes sending me data. But I am not sure I would get the same enjoyment out of just processing. I am not that fond of processing Hubble images--though its such a PITA to get the data that that probabkly has something to do with it.

That is what I am coming to believe as well. My question is if there is shift in the focuser so that dust motes move--why not stars. One might say that the registration process will align all the stars--which is true, but there would be registration artifactsv at the edges of the stack. I get those becuase I manually align the FOV after focusing. But If I shoot 100 subs and do not refocus (it happened the other night. FWHM stayed between 1.6 and 2.1 for hours....in my sky, that is as good as it gets), there is no stacking artifacts. So I am a bit unclear how a shifting focuser can impact calibration but not registration.

I asked John Hayes about that-he is reknown for his C14 system and I thought he might have an idea. He said "the Celestron mirror locks are not perfect, but they are giod enough to provide good calibration". Based on conversations with him, and here, I suspect its the focuser, not the mirror flop. Maybe its loose. There are a number of set screws and thumb screws. I wil tighten it up and see if that helps....over a langastino lunch

Ahhh….I’m doomed. I’m thinking of Toni scope. It’s reasonable to belong to 3 piers and get data from 3 scopes. Not the same though.

Very nice. It’s good to know it’s me and not the data. My sky is very poor, so I am not surprised there is some issue. I wonder how much data I would need to really bring out the dim stuff. Your image Izzy very sharp, and I like the color. While I think my latest version is my best. It doesn’t compare to yours. I just figured out that my flats dong work because of mirror flop. The mirror is locked down and I focus with a crayford. But the focus star still shifts when I focus. Flats will never work and this scope is doomed unless I fix it. Not sure how

Well, I already know there is mirror flop. I see it when I focus. The focus star shifts. The mirror is locked down using 3 mirror lock knobs. I added a focuser to the back. I focus using a crayford shorty and the mirror remains locked. Not sure why there is flop. But it’s definite. Not sure what the fix is, seeing that I already use the fix. But the fix doesn’t work

It’s probably mirror flop. Even with the mirror locked down with the mirror lock knobs and focusing with crayfish at back of scope I see movement of the focus star when I focus. I thought the mirror locks were suppose to lock down the mirror. How to fix this?

The panel must be perpendicular to the axis. It has to be flat. The only way that I can do this is to put it on top with the scope pointing at zenith. I just don’t see how I can do it otherwise unless I build a wall and hang it.

I tried sky flats. Terrible. They work well with fsq but not c11. Maybe I need a diffuser

I am into planetary and lunar. But an exoplanet? Not so much. It is interesting, but I like imaging the m42s of the galaxy. The image of an exoplanet, or graph more likely, would not be too impressive above the mantle

I don't think so. The panel forms a tight seal with the tube. Could be internal reflection-but it doesn t seem to be that--dust particles are not being canceled out--but there is no streaking or flares that would suggest a light leak

Not really possible to put it far away. It is designed to sit on top of the tube. I don't have a an observatory wall to hand it on. Besides, then I would need a panel 3x the size.

I am getting so tired of flats not working. Yes, dust specks can move between the light frames and the flat frames invalidating the flats....but every time? This is getting tiresome. I have tried flats with the histogram about1/4, 1'3 and 1/2 and none work--there is ALWAYS dust motes or partial dust motes that remain. Why? I use 50-100 flats ranging from .5 sec to 2 sec. So far the .5 sec ones work the best. But others say its best to use 2-10 sec. I use flat darks of the same temp and duration as my flats. What is the secret? I am not referring to false IFN cloud like blemishes. I think they are from hazy sky (high clouds, poor transparency. Its the dust specs that are infuriating. How can they move EVERY time? I shoot flats immediately after collecting lights. I don't know what else to do This is NGC 5905 and 5908--only the red and green channels. It is an RGG image. The FWHM of the green stack is 1.6. I used all 161 subs. A very consistent night. Guiding errors remained .39-.42" But the green flats did not work. I had to do a lot of work to clean this image up. I made it to see if I could salvage the data--or if I had to throw it out. Imagine throwing out 5.3 hours of subs with FWHM of 1.8. Its rare that seeing for me allows this. The red stack has a FWHM of 2.6--and I was lucky to achieve this...it was a blustery night and I threw out 50% of the data. Though far from a good background, based on this image, I think I will keep the green and proceed with blue then Lum. But I am really getting fed up with flats. I was lucky that none of the dust motes were in the galaxies. I use a Flatman panel. Histogram levels are 1/4-1/2. I use flat darks of same temp and duration. What could it be? C11 Edge with .7x reducer and ASI 1600 red: 158 120 sec; Green: 161 120 sec. About 11 hours Here's with a bit more red. Cant decode which is better

Last night I was pulling down fwhm of 1.6. My best. What you say is true. Not much to do about seeing. That is why I am looking by to remote operations