Help with processing M33

[Guy]

Hi

The single sub-frame looked very dark to me - showing the filter is working well but you don't have much in the way of signal.
Its histogram is well over towards the left axis so I think you need longer exposures if you are using the filter.

Since there is so little signal the stacking is not having the sort of beneficial effect you would expect.
Perhaps try taking a sequence using increasing exposure lengths - keeping the ISO the same - until the subs are definitely over-exposed - and then see which one seems the best balance.

Guy

[Arrowstar]

Hi everyone,

I've had the opportunity to come back with more data and try again at M33. I was hoping I could get some help processing this stack, as it's still a challenge. This stack includes about 1 hour of 3 min subs and ISO 400 and 1 hour of 3 minute subs at ISO 800. As you can see, I'm trying to find a setting that works for me and my awful red zone light pollution...

Here's the stacked image:
https://dl.dropboxusercontent.com/u/291 ... acked1.TIF

Here's what I was able to do with it in Star Tools:
https://dl.dropboxusercontent.com/u/291 ... rTools.tif

I'd really appreciate it if someone else could take a go at it. I realize I still need more time on the target, but between cloudy nights and very bright urban lights just below the target, 1 hour per night of usable subs is all I appear to be able to get from my location (and this is with a light pollution filter!).

Thank you.

[Cheman]

Hi Arrowstar,
I had a go at your data, what you have seems pretty good, you just,as you mentioned, need more of it. There is no substitute for photons
below is my result along with the log file.
Che

M33_20160927_20161005_stacked1 (Medium).jpg (153.85 KiB) Viewed 9264 times

File loaded [C:\Users\Che\Downloads\M33_20160927_20161005_stacked1.TIF].
---
--- Crop
Parameter [X1] set to [68 pixels]
Parameter [Y1] set to [68 pixels]
Parameter [X2] set to [4201 pixels (-89)]
Parameter [Y2] set to [2774 pixels (-82)]
--- Bin
Parameter [Scale] set to [(scale/noise reduction 70.71%)/(200.00%)/(+1.00 bits)]
Undo.
--- Bin
Parameter [Scale] set to [(scale/noise reduction 50.00%)/(400.00%)/(+2.00 bits)]
--- Wipe
Parameter [Mode] set to [Correct Color & Brightness]
Parameter [UNKNOWN] set to [Yes]
Parameter [Precision] set to [256 x 256 pixels]
Parameter [Dark Anomaly Filter] set to [1 pixels]
Parameter [Drop Off Point] set to [100 %]
Parameter [Corner Aggressiveness] set to [100 %]
Parameter [Aggressiveness] set to [75 %]
--- Develop
Parameter [White Calibration] set to [Use Stars]
Parameter [Gamma] set to [1.00]
Parameter [Skyglow] set to [0 %]
Parameter [Digital Development] set to [84.78 %]
Parameter [Blue Luminance Contrib.] set to [100 %]
Parameter [Green Luminance Contrib.] set to [100 %]
Parameter [Red Luminance Contrib.] set to [100 %]
Parameter [Dark Anomaly Headroom] set to [5 %]
Parameter [Dark Anomaly Filter] set to [Off]
--- Contrast
Parameter [Expose Dark Areas] set to [No]
Parameter [Compensate Gamma] set to [No]
Parameter [Precision] set to [256 x 256 pixels]
Parameter [Dark Anomaly Filter] set to [1 pixels]
Parameter [Aggressiveness] set to [75 %]
Parameter [Dark Anomaly Headroom] set to [15 %]
--- Wavelet Sharpen
Parameter [Intelligent Enhance] set to [Yes]
Parameter [Scale 1] set to [100 %]
Parameter [Scale 2] set to [100 %]
Parameter [Scale 3] set to [100 %]
Parameter [Scale 4] set to [100 %]
Parameter [Scale 5] set to [100 %]
Parameter [Mask Fuzz] set to [8.0 pixels]
Parameter [Amount] set to [100 %]
Parameter [Small Detail Bias] set to [75 %]
--- Life
Parameter [Detail Preservation] set to [Linear Brightness Mask]
Parameter [Compositing Algorithm] set to [Multiply, Gamma Correct]
Parameter [Inherit Brightness, Color] set to [Off]
Parameter [Output Glow Only] set to [No]
Parameter [Airy Disk Sampling] set to [128 x 128 pixels]
Parameter [Airy Disk Radius] set to [8 pixels]
Parameter [Glow Threshold] set to [0 %]
Parameter [Detail Preservation Radius] set to [20.0 pixels]
Parameter [Saturation] set to [100 %]
Parameter [Strength] set to [100 %]
Parameter [Mask Fuzz] set to [1.0 pixels]
--- HDR
Parameter [Small Detail Precision] set to [Max]
Parameter [Channels] set to [Brightness Only]
Parameter [Algorithm] set to [Optimize Hard]
Parameter [Dark/Bright Response] set to [Full]
Parameter [Detail Size Range] set to [21 pixels]
Parameter [Noise Suppression] set to [1.2]
--- Develop
Parameter [White Calibration] set to [Use Stars]
Parameter [Gamma] set to [1.00]
Parameter [Skyglow] set to [0 %]
Parameter [Digital Development] set to [87.23 %]
Parameter [Blue Luminance Contrib.] set to [100 %]
Parameter [Green Luminance Contrib.] set to [100 %]
Parameter [Red Luminance Contrib.] set to [100 %]
Parameter [Dark Anomaly Headroom] set to [5 %]
Parameter [Dark Anomaly Filter] set to [Off]
--- Color
Parameter [Cap Green] set to [To Yellow]
Parameter [Bias Slider Mode] set to [Sliders Reduce Color Bias]
Parameter [Style] set to [Scientific (Color Constancy)]
Parameter [LRGB Method Emulation] set to [Straight CIELab Luminance Retention]
Parameter [Dark Saturation] set to [2.00]
Parameter [Bright Saturation] set to [Full]
Parameter [Saturation Amount] set to [424 %]
Parameter [Blue Bias Reduce] set to [2.09]
Parameter [Green Bias Reduce] set to [1.75]
Parameter [Red Bias Reduce] set to [1.00]
Parameter [Mask Fuzz] set to [1.0 pixels]
--- Wavelet De-Noise
Parameter [Scale 1] set to [90 %]
Parameter [Scale 2] set to [90 %]
Parameter [Scale 3] set to [90 %]
Parameter [Scale 4] set to [90 %]
Parameter [Scale 5] set to [0 %]
Parameter [Mask Fuzz] set to [1.0 pixels]
Parameter [Scale Correlation] set to [6]
Parameter [Color Detail Loss] set to [12 %]
Parameter [Brightness Detail Loss] set to [12 %]
Parameter [Grain Size] set to [4.6 pixels]
Parameter [Read Noise Compensation] set to [Off]
Parameter [Smoothness] set to [75 %]
--- Magic
Parameter [Mode] set to [Shrink]
Parameter [Mask Grow] set to [1 pixels]
Parameter [Iterations] set to [2 pixels]
File saved [C:\Users\Che\Downloads\M33_20160927_20161005_stacked1.jpg].

[Arrowstar]

Thank you! I will certainly gather more photons is it were. I feel like I probably need about 4 hours work to get something decent out of it, so maybe another night or two of imaging. Appreciate the help!

[Arrowstar]

Hi everyone!

I'm back with another 2 hours of data on M33. I was hoping someone could take a crack at it as before? I feel like I'm getting close. This image includes not only another 2 hours of data, but I was able to drizzle the image with BackyardEOS, so I'm hoping that reduces the noise characteristics some. Total integration time is ~4 hours. Individual subs are 3 minutes long at ISO 800.

Here's the image, straight out of DSS: https://dl.dropboxusercontent.com/u/291 ... acked1.TIF

As usual, darks, flats, and bias frames were applied. Would definitely appreciate the help as I attempt to continue learning StarTools myself. I would really like to see if I can't bring out more detail without turning the background into a sea of red, green, and blue!

For the record, here is my own attempt at this stack: https://dl.dropboxusercontent.com/u/291 ... rTools.tif

The blue color is because I use a CLS filter in my Canon T3.

Thank you for the help!

[Cheman]

Hi Arrowstar
here's my processing of your new stack. As far as noise, and keeping in mind that I do not use a DSLR and am not familiar with their noise characteristics and such, I'm wondering if your calibration frames could be contributing to noise. You might want to try stacking without the dark frames and see if it makes a difference. Just a thought.

Che

M33_20161005_20161013_stacked1.jpg (343.04 KiB) Viewed 9220 times

File loaded [C:\Users\Che\Desktop\M33_20161005_20161013_stacked1.TIF].
---
--- Crop
Parameter [X1] set to [426 pixels]
Parameter [Y1] set to [300 pixels]
Parameter [X2] set to [3985 pixels (-305)]
Parameter [Y2] set to [2574 pixels (-282)]
--- Bin
Parameter [Scale] set to [(scale/noise reduction 50.00%)/(400.00%)/(+2.00 bits)]
--- Wipe
Parameter [Mode] set to [Correct Color & Brightness]
Parameter [UNKNOWN] set to [Yes]
Parameter [Precision] set to [256 x 256 pixels]
Parameter [Dark Anomaly Filter] set to [1 pixels]
Parameter [Drop Off Point] set to [0 %]
Parameter [Corner Aggressiveness] set to [100 %]
Parameter [Aggressiveness] set to [75 %]
--- Develop
Parameter [White Calibration] set to [Use Stars]
Parameter [Gamma] set to [1.00]
Parameter [Skyglow] set to [0 %]
Parameter [Digital Development] set to [87.23 %]
Parameter [Blue Luminance Contrib.] set to [100 %]
Parameter [Green Luminance Contrib.] set to [100 %]
Parameter [Red Luminance Contrib.] set to [100 %]
Parameter [Dark Anomaly Headroom] set to [5 %]
Parameter [Dark Anomaly Filter] set to [Off]
Undo.
Redo.
--- Deconvolution
Parameter [Image Type] set to [Deep Space]
Parameter [Mask Behavior] set to [De-ring Mask Gaps, Hide Result]
Parameter [Radius] set to [1.6 pixels]
Parameter [Iterations] set to [6]
Parameter [Regularization] set to [1.00 (optimal noise and detail)]
Parameter [Mask Fuzz] set to [8.0 pixels]
--- Contrast
Parameter [Expose Dark Areas] set to [No]
Parameter [Compensate Gamma] set to [No]
Parameter [Precision] set to [256 x 256 pixels]
Parameter [Dark Anomaly Filter] set to [1 pixels]
Parameter [Aggressiveness] set to [85 %]
Parameter [Dark Anomaly Headroom] set to [15 %]
--- Wavelet Sharpen
Parameter [Intelligent Enhance] set to [Yes]
Parameter [Scale 1] set to [100 %]
Parameter [Scale 2] set to [100 %]
Parameter [Scale 3] set to [100 %]
Parameter [Scale 4] set to [100 %]
Parameter [Scale 5] set to [100 %]
Parameter [Mask Fuzz] set to [8.0 pixels]
Parameter [Amount] set to [100 %]
Parameter [Small Detail Bias] set to [75 %]
--- Life
Parameter [Detail Preservation] set to [Linear Brightness Mask]
Parameter [Compositing Algorithm] set to [Multiply, Gamma Correct]
Parameter [Inherit Brightness, Color] set to [Off]
Parameter [Output Glow Only] set to [No]
Parameter [Airy Disk Sampling] set to [128 x 128 pixels]
Parameter [Airy Disk Radius] set to [8 pixels]
Parameter [Glow Threshold] set to [0 %]
Parameter [Detail Preservation Radius] set to [20.0 pixels]
Parameter [Saturation] set to [100 %]
Parameter [Strength] set to [100 %]
Parameter [Mask Fuzz] set to [1.0 pixels]
--- Color
Parameter [Cap Green] set to [To Yellow]
Parameter [Bias Slider Mode] set to [Sliders Reduce Color Bias]
Parameter [Style] set to [Scientific (Color Constancy)]
Parameter [LRGB Method Emulation] set to [Straight CIELab Luminance Retention]
Parameter [Dark Saturation] set to [2.00]
Parameter [Bright Saturation] set to [Full]
Parameter [Saturation Amount] set to [352 %]
Parameter [Blue Bias Reduce] set to [2.04]
Parameter [Green Bias Reduce] set to [1.95]
Parameter [Red Bias Reduce] set to [1.00]
Parameter [Mask Fuzz] set to [1.0 pixels]
--- Wavelet De-Noise
Parameter [Scale 1] set to [90 %]
Parameter [Scale 2] set to [90 %]
Parameter [Scale 3] set to [90 %]
Parameter [Scale 4] set to [90 %]
Parameter [Scale 5] set to [0 %]
Parameter [Mask Fuzz] set to [1.0 pixels]
Parameter [Scale Correlation] set to [6]
Parameter [Color Detail Loss] set to [12 %]
Parameter [Brightness Detail Loss] set to [12 %]
Parameter [Grain Size] set to [4.5 pixels]
Parameter [Read Noise Compensation] set to [Off]
Parameter [Smoothness] set to [75 %]
File saved [C:\Users\Che\Desktop\M33_20161005_20161013_stacked1.jpg].

[Arrowstar]

Hey thanks! I'll give your suggestion a try and attempt to duplicate your method on that new stack. By the way, do you think there is more detail to be gathered here or would I be wasting my time with more subs?

[Cheman]

The reason I suggested stacking w/o the darks is that I've heard dslr's these days have much lower dark current than in the past. If you stack darks that arent 1. really necessary, or 2. not properly matched to the lights, with respect to temp. I've read that this can introduce more noise. I'm not sure how much more signal can be brought out of your image, but if noise is being brought in by the calibration frames, your s/n ratio will suffer for it. At any rate, it will be an interesting experiment to stack without the darks and see what happens. I think your best bet would be to try to take longer subs as suggested earlier in this thread. For example, my image of M33

was done with( 50 ) eight minute subs and no dark frames (it is a OSC ccd camera-QHY8) so we arent comparing apples to apples, but perhaps your subs could be pushed a bit longer, again I dont know and am not really familiar with dslrs. I do know there is some point at which increasing the iso settings is counterproductive, perhaps Ivo or someone else who uses dslr camera could chime in.

Che

[Arrowstar]

Here's what I ended up with after removing the Darks and following your general approach to processing the image:

https://dl.dropboxusercontent.com/u/291 ... rTools.tif

What do you think?

[Cheman]

Looks to me like you've made some progress. did you find there was less noise in this stack? If so possibly your darks were not done at the same temp as the lights. In another thread here, someone posted about a program called darkmaster which may be of use. https://sourceforge.net/projects/darkmaster/
Che