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Support (Please note, this is primarily a user forum, for direct Atik support, please email support@atik-cameras.com) => Atik Horizon => Topic started by: bwa on April 23, 2018, 02:22:33 am

Title: Horizontal Banding - Color Horizon - Still a problem!
Post by: bwa on April 23, 2018, 02:22:33 am
Version 4.2.2.1 of the core software has partially resolved my horizontal banding problem, i.e.: the banding is less severe, but it is still present when one does a strong image stretch!

The attached image is of the Leo Trio of galaxies, M66+: 21x60 sec., Med Gain setting, 4x4 binning (Normal), aligned and stacked from captured subs.  The banding gets considerably worse as the exposure time goes down and is present in all bin modes and all gain settings.  And it doesn't make any difference if an image is live aligned & stacked or processed from subs.

bwa
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: Edwardnut on April 23, 2018, 03:37:37 am
I want to know Can I fix this? Or wait for it to return to normal.
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: bwa on April 24, 2018, 08:51:57 am
Spent another night imaging with exactly the same setup as previously; no banding and no idea why!?  It is rather frustrating not knowing how everything is going to work from one night to the next.
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: bwa on May 28, 2018, 01:50:45 am
I think I've found the problem with horizontal banding, at least for my color Horizon; others might be different.

The banding seems to tie to the Offset used.  The fault Gain/Offset values, per ATIK support are:
...Low: Gain 1, Offset 17
...Med: Gain 6, Offset 29
...High: Gain 30, Offset 139

When I enter the above values in the Custom selection I get distinctly different results than when I select Low, Med or High.  It almost appears the Offset being applied by the Low, Med and High is not being used or is lower than stated; thus, giving rise to horizontal banding of various degrees. 

This is an instance where light pollution is actually a benefit by setting an artificial Offset; thus, imagers with lots of light pollution will probably have no problem with horizontal banding.  However, imagers in a dark site may see banding!

Until this problem is resolved by ATIK Support I would suggest using the Custom selection and setting your own Gain and Offset values.  You can use the ones above or select them from the graph (PDF file) I've attached.

Enjoy!

bwa
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: dpaul on May 31, 2018, 01:03:42 am
Hi BWA,

I believe banding is quite common with various types of ''cooled'' CMOS cameras (not just Atik). I'm no expert but on some nights I get it and others less so (I'm mainly using the Horizon mono). Maybe its a certain combination of cooling level, gain, etc. I wanted to share details of an amazing tool in Pixinsight - I do all my processing with this software.  The method is called ''canon banding removal'' and can be found as one of the ''script tools''.


Attached is your original frame that you posted in April and in only a few seconds this tool removed all evidence.
I use is much of the time so no issues at all with banding. There are many other reasons for using Pixinsight

Hope this helps.

Dave
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: Astrogate on May 31, 2018, 06:08:11 pm
I guess this is okay if you are using the Horizon for imaging along with post processing but why I held off from buying one of these cameras is it EAA usage. This camera what developed also to be use with the Infinity software for EAA or near real-time observing and if the banding is this bad then I do not see this as a successful EAA device unfortunately. Both my ZWO ASI 183 mono and ASI 1600 color has no banding at all!!

Chris
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: bwa on June 04, 2018, 03:38:00 am
I guess this is okay if you are using the Horizon for imaging along with post processing but why I held off from buying one of these cameras is it EAA usage. This camera what developed also to be use with the Infinity software for EAA or near real-time observing and if the banding is this bad then I do not see this as a successful EAA device unfortunately. Both my ZWO ASI 183 mono and ASI 1600 color has no banding at all!!

Chris
If you saw my previous post, there is no banding if the Gain/Offset are set properly.  As I said, set the Gain/Offset in Custom.  Using the Low, Med or High defaults can result in banding.  ATIK Support has been notified of the problem BUT has not responded!!

And yes, PixInsight does has a script to reduce/eliminate the banding BUT I would prefer not to have the banding in the first place...

bwa
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: Astrogate on June 04, 2018, 06:07:23 pm
Sorry Brian but I am talking about EAA and not imaging. I am sure Atik will resolve the gain/offset issues so one does not have to manually select the proper matching.

Chris
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: CraigG on December 31, 2018, 04:56:38 pm
bwa-

Any new updates on the banding issue from either your experience or from Atik? I'm also noticing horizontal banding in my images from a Horizon OSC. I've attached a way overexposed image to highlight what I'm seeing with regular stretches in most images with light or nebulous areas. As I am trying to stay as close to simple EAA as possible, I'm not interested in using post processing tools to remove them! This image is 2x2 binned with the stock Medium gain setting (not set in Custom yet as you suggested).

Thanks...
Craig
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: dpaul on January 02, 2019, 11:51:11 pm
Hi Craig,

With the Horizon mono camera how many frames are you taking for each Red, Green, Blue and Luminance filters?
Also wondering if you are taking Bias and Dark frames to calibrate each of the light frames?
Usually I take a minumum of 12 frames per filter and ideally 20, this makes a big difference to the signal/noise ratio of the final integrated image. This won't necessarily get rid of all the banding but proably reduces it.

As per my previous note, horizontally banding seems to be a common feature of CMOS cameras from various manuafucturers.
I haven't played around with the gain setting that BWA suggests (which may indeed be useful) but because they can easily be removed in post processing, its a non-issue for me.

Over the last 18 months I've changed from hating any type of imaging (visual only was my interest). Then I got into semi-real time video and soon realised there was a lot more data in the image if it was post processed. A year ago I then bought an Atik Horizon mono camera and started playing around with post processing. Even simple processing with Pixinsight gives amazing results. I now get equal satisfaction out of the processing as I do the capturing - never thought that would happen.


Just wanted to share my experience as someone that was 100% against post processing but now now my interest in deep sky objects is way higher.

Regards

David
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: CraigG on January 03, 2019, 01:00:01 am
Hi David!

Thanks so much for sharing your journey to this point. It really helps! I guess we should never say that we're 100% committed to enjoying this hobby in only one way with all of the options that are available. Since my last post, I've read comments from other imagers suggesting using the PI tool  to remove the banding just as you suggested. Although I'm waiting to hear back from Atik, I'm already moving toward...however reluctantly...to the post-processing camp. I was hoping that the promise of EAA would satisfy my needs for the foreseeable future after a few years of less than satisfying results from processing images from my SBIG 8300c.

To answer your questions, I have been using my Horizon OSC strictly stock with no filters or adding bias/dark frames. The Horizon was a next step up from my Infinity OSC and I'd hoped to use it in the same way.

Anyway, thanks again for your counsel and I may be picking your brain a bit when I start working with PI.

Out of curiosity, would you be able to use the Canon tool on my attached image of Pleiades so I can see the improvement? I would be grateful!

Best wishes,

Craig
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: dpaul on January 06, 2019, 11:50:00 pm
Hi Craig,

The debanding tool is meant to be used on the linear image before histogram stretching. I have however tried on your image and it made 'some' difference (see attached). The tool can add lines if over-used so its a fine balance.

David
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: dpaul on January 06, 2019, 11:51:03 pm
Sorry Craig

Forgot the attachment.

Here it is

David
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: bwa on January 07, 2019, 12:47:13 am
Hi David!

Thanks so much for sharing your journey to this point. It really helps! I guess we should never say that we're 100% committed to enjoying this hobby in only one way with all of the options that are available. Since my last post, I've read comments from other imagers suggesting using the PI tool  to remove the banding just as you suggested. Although I'm waiting to hear back from Atik, I'm already moving toward...however reluctantly...to the post-processing camp. I was hoping that the promise of EAA would satisfy my needs for the foreseeable future after a few years of less than satisfying results from processing images from my SBIG 8300c.

To answer your questions, I have been using my Horizon OSC strictly stock with no filters or adding bias/dark frames. The Horizon was a next step up from my Infinity OSC and I'd hoped to use it in the same way.

Anyway, thanks again for your counsel and I may be picking your brain a bit when I start working with PI.

Out of curiosity, would you be able to use the Canon tool on my attached image of Pleiades so I can see the improvement? I would be grateful!

Best wishes,

Craig
Craig,
You stated: "As I am trying to stay as close to simple EAA as possible".  This is NOT possible with the Horizon camera / Infinity software at its current state of development, at least from my experience.  In fact it takes additional effort to get rid of the horizontal banding from Horizon images regardless of the postprocessing you undertake!!  And yes, the Canon script in PixInsight does work most of the time (not always); however, a good astronomy camera should not require this additional step.

I've downloaded and installed the most recent version of the Infinity software in hopes it did something WRT the banding problem; no improvement, sadly!

Some people have said this is a problem with all CMOS sensors.  Personally I think it is solely an ATIK problem.  As I've mentioned previously I would have purchased a mono Horizon if the OSC Horizon banding had been resolved.  It wasn't and I purchased a QHY 163M which uses the same CMOS sensor as the Horizon.  I can stretch subs off the QHY 163M to the extreme and get NO banding.  I also image with a fellow using a ASI1600MM Pro camera which has the same Panasonic sensor and have never seen banding in his images, some of which I've processed.  I'm quite sure the banding problem comes right back to what ATIK is doing in hardware/software with the Horizon cameras!?  I suspect ATIK support has not addressed the problem because they have no cure without redesigning the Horizon camera...

The poor man's resolution to the banding problem is 1) don't shoot subs requiring a stretch, 2) use the Canon script in PixInsight to reduce/eliminate the problem.  Not ideal, but at least a partial solution.

bwa
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: CraigG on January 08, 2019, 08:19:11 pm
David...thanks so much for processing that image!

I do see some improvement and I understand that the PI tool is better utilized before stretching. I still have a service ticket pending with Atik so we'll see what they say about the banding. Maybe they are working on something they can fix in Infinity? In the meantime, I'm reading up on PI before taking the plunge!

Best wishes,
Craig
 
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: CraigG on January 08, 2019, 08:48:24 pm
bwa,

Thanks so much for your comments! I'm still holding out hope that Atik can implement a software fix for this banding issue however your experience with other 1600 cameras doesn't bode well at this point. Before your positive comment about the ASI1600MM Pro I wondered if one of the reasons that ZWO discontinued their 1600MC Pro was in part due to banding. Anyway, as I commented to David, I'm communicating with Atik on the issue and my fingers are still crossed that a EAA friendly fix can happen! I've found Atik to be VERY responsive to my questions so far. Maybe our shared concerns will prompt a successful outcome!

Best wishes,
Craig
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: atikuser on July 29, 2020, 06:40:11 pm
I'm and electrical engineer, and I helped a friend by repairing the power connector on his Atik Horizon.  The power cable was pulled sideways during a mount slew and one of the connector pins was sheared off at the pc board interface.  Replacing the connector solved that problem.

To the thrust of this post.

When I had the Atik Horizon disassembled, I took pictures.  One bad thing I noticed is the heavy power leads to the Peltier cooler run right above the flat cable connecting to the sensor.  This situation is a perfect setup for electromagnetic coupling from the Peltier drive signal into the video signals.  Please see the attached pc board photograph.

In all likelihood, the high-current, low-voltage Peltier drive is obtained via pulse-width modulation of the 12V supply.  Note the power transistor and inductor near the pc board termination of the Peltier drive wires that could form such a low-loss high-current low-voltage down converter.

Pulse-width modulation involves high frequency square-wave switching between the 12V supply and ground.  Square waves are rich in harmonics, which can wreak havoc on other circuits if not properly managed, shielded, and/or filtered.

At a very least, the Peltier drive wires should be twisted.  Ferrite beads placed on these wires will also probably help, as will filtering on the prime 12 volt power.

I no longer have access to the Atik Horizon, as we now live an 8-hour drive apart, so I can't test this hypothesis or do spectrum analysis using a small "sniffer" pickup coil held above the operating pc board to search for problematic electromagnetic signals.
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: atikuser on July 29, 2020, 06:49:23 pm
I'm and electrical engineer, and I helped a friend by repairing the power connector on his Atik Horizon.  The power cable was pulled sideways during a mount slew and one of the connector pins was sheared off at the pc board interface.  Replacing the connector solved that problem.

To the thrust of this post.

When I had the Atik Horizon disassembled, I took pictures.  One bad thing I noticed is the heavy power leads to the Peltier cooler run right above the flat cable connecting to the sensor.  This situation is a perfect setup for electromagnetic coupling from the Peltier drive signal into the video signals.  Please see the attached pc board photograph.

In all likelihood, the high-current, low-voltage Peltier drive is obtained via pulse-width modulation of the 12V supply.  Note the power transistor and inductor near the pc board termination of the Peltier drive wires that could form such a low-loss high-current low-voltage down converter.

Pulse-width modulation involves high frequency square-wave switching between the 12V supply and ground.  Square waves are rich in harmonics, which can wreak havoc on other circuits if not properly managed, shielded, and/or filtered.

At a very least, the Peltier drive wires should be twisted.  Ferrite beads placed on these wires will also probably help, as will filtering on the prime 12 volt power.

I no longer have access to the Atik Horizon, as we now live an 8-hour drive apart, so I can't test this hypothesis or do spectrum analysis using a small "sniffer" pickup coil held above the operating pc board to search for problematic electromagnetic signals
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: vince on July 30, 2020, 04:07:09 pm
Hello Bruce,

Thanks for the feedback which is of course always welcome :)  I believe Andrew has got back to Richard about this.

Vince



Hello Richard,

Thank you for your email, Vince did mention that he had recently read Bruce's original forum post.

The signal coming out of the Horizon's CMOS sensor is at a frequency that is of orders of magnitude greater than that used to control the peltier module. Therefore, its affect on the quality of the final image is relatively small. However, because we are always trying, where possible, to reduce all sources of noise, we have tackled this issue in a novel way.

During the period when the image data is passed from the sensor to the main PCB, the dynamic cooling control is momentarily suspended so that what was a small issue is now completely removed.

One of the main sources of noise in such complex and compact designs, is crosstalk between the very high speed clocks operating in different parts of the circuit. One of the principal concerns of a camera designer, is to prevent this sort of problem becoming a significant issue. In fact, it is almost an obsession, and requires a great deal of experimentation. Sometimes, a seemingly logical solution actually generates unexpected or undesirable results.

The original Horizon camera was our first foray into designing a CMOS based camera, as opposed to one utilising a CCD. We believe that we did a very good job, Inevitably, since that time, we have gained more experience and have developed new ideas, some of which have been introduce into the Horizon II camera. This is all part of the gradual evolution of  hi-tech products.

I hope that you find my explanation useful

Best Regards,

Andrew

Atik / QSI / Opus Service
Unit 8 Lodge Farm Barns
New Road
Bawburgh
Norwich
NR9 3LZ
UK
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: susan-parker on August 01, 2020, 02:23:49 pm
The problem here is that the ADCs are in the CMOS sensor, not separate like with a CCD, so any high-frequency punch-through will be from the Peltier to the sensor.

Additionally, Peltiers are non-linear devices and really don't like to be switched with a PWM signal - although obviously it does mostly work if it's kept within a tight temperature feedback loop.

There is an inductor (marked 2R2) which is next to the MOSFET transistor however I don't think it is part of the Peltier supply (despite being a lot chunkier than the other regulators) as there is a test-point marked 1V.

If it isn't already implemented in the Horizon (I can't see what might be on the other side of the board) my recommendation would be to introduce an LC filter the same way as one does for Class-D audio amplifiers, to smooth out the switching waveform to something more resembling DC. It doesn't have to be super smooth, just not switching the full 12V.
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: atikuser on August 01, 2020, 04:37:35 pm
Susan,

Thanks for the response.  I didn't trace out the circuitry, but obviously could.  Here is a picture of the PC board backside; resolution reduced for manageable file size.  The heat sink pins obscure part of the PC board. 

I've designed Peltier cooler controls, and did use switching power supplies.  There are simple tricks to separate the high frequency feedback from the regulated output feedback, so the Peltier device only sees DC.

This system has a very wide range of signal voltages, from the PWM power supplies, to the low level signals compromising the 12- bit precision video signals.  The banding occurs in the darker areas of the image.

Regards

Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: atikuser on August 01, 2020, 04:57:58 pm
Andrew,

Thank you for a useful and informative explanation.  Yes unexpected experimental results can be startling, but also informative.  I wish you luck in your quest.

As I said, I am an electrical engineer who worked for a General Motors advanced research facility for 37 years.  In the last 15 years of my tenure, I was sent all over the corporation to solve electronic problems, many of which involved frequencies and interference like those under question.

Sometimes, problem solutions are very obscure.  A case in point was a piece of military electronics on a light armored vehicle (LAV) that malfunctioned sporadically and randomly when the 25mm cannon was fired.  I studied that problem for many months, attending firing exercises all over North America. 

I finally found the problem was direct sunshine illuminating a laser sensor created a photodiode bias voltage, which was blocked by a coupling capacitor, so the bias voltage was blocked into further electronics.  It turned out that shock from the cannon firing compressed the glass-epoxy pc board enough to change its capacitance and create a voltage: I = d/dt(CV).  This displacement current created a voltage in the associated circuitry.  Changing and thickening the pc board material solved the problem.

Yes, I would expect the Peltier module control switching frequency is significantly lower than the CMOS sensor scan frequency.  With pulse width modulation (square wave) used to control the switching regulator for the Peltier cooler drive wires, high frequency harmonics are present, albeit somewhat filtered.   As you know, inductors have capacitance, and they only function as inductors below their self resonant frequency.  Short high frequency current paths are also very important.

I would agree that the Peltier PWM switching frequency is probably many orders-of-magnitude below the video clock frequencies.  You also have the opposite orders-of-magnitude difference between the switching regulator waveforms and the video output signals (before on-chip A/D conversion).

Since the banding is somewhat suppressed, i.e, only affects lower level signals, even more attenuation of interfering signals to the video signals may be needed.

When I see a potentially problematic electromechanical design, like the Peltier drive wires in a big open loop directly above low level video signals, I get concerned.

There are simple tests that can be done to prove or disprove this conjecture.  The simplest of which is to raise the Peltier drive wires away from the video flat cable and press them together to minimize coupling area.  Compare the banding in before and after photos.

Subsequently, add a shield over the video flat cable area.  Such a shield can be a small piece of single-sided 0.31" PC board material. The ground connection should be as short as possible.   Retest, as before.

If there is an improvement, then the above conjecture is valid.

You have a tiger by the tail, judging from the blogs complaining about the problem, i.e., disappointed customers who  bought an expensive camera.

I hope you find a solution soon.

Regards,
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: susan-parker on August 01, 2020, 09:35:44 pm
Hi,

Just to repeat, the CMOS sensors have the ADCs on the chip, so there are no analog signals coming out of the sensor, so the banding cannot be coming from this.

However there are analog signals going into the sensor, in the form of the various power supplies. Modulation on the power might cause an artefact in the chip, particularly something that affects the ADCs reference levels.

Or the banding may be simply differences in the ADCs and gains of the sensor as there is stuff going on in the chip doing analog twiddling things.

I know that overloading a full well causes banding from brightest stars, which is obvious full width streaks.

As an aside I would note that I am imaging with strong background light pollution (Bortle 8+), which apparently is masking this effect to some degree. I usually ruin at high-gain in Dusk and my images come out of stacking with high background levels.

Taking a look at the Panasonic sensor specifications there is a lot going on in the chip, unlike a CCD sensor:

https://industrial.panasonic.com/ww/eol/semiconductors/imagesensors/broadcasting-digital-still-camera/models/MN34230

... and the character of the CMOS sensors will be similar to other parts.

To get the best out of the Horizon one should really do white-light calibration, which should sort out some of these issues. I have a flat-light box, need to get round to using it!

Best,
Susan.
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: atikuser on August 02, 2020, 10:02:26 am
Susan,

Twice now you have related that the CMOS sensor has the ADC on chip.  If interference is being injected, it really matters in what way it evidences.  Yes, noise on digital lines, if low, can be ignored.  Noise on other lines may not be able to be ignored.  One must look at all possibililties.

Atik recognized the noise in the Peltier switching power supply was causing problems, and the solution was to gate off the PWM switching during some CMOS sensor operations.  What about transient die downs, and switching noise from other power supplies?

The Peltier cooler is directly in back of the sensor.  The banding problem is a low-level phenomenon, i.e., affecting dark image areas.  I think EMI interference is related to the problem. 

The Panasonic MN34230 16 MP CMOS sensor requires three supply voltages: 3.3, 1.8, and 1.2 volts.  This product is being discontinued, so I can only find a cursory data sheet.

How are these voltages being generated?  What is the effect of ripple on them (synchronous, non synchronous).  As I said in a previous post, the devil is in the details.

Atik has now introduced the Horizon II.  Does it have the banding problem?  Does it use a newer sensor?

Atik has disappointed customers who bought an expensive camera.  Don't ignore them.
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: susan-parker on August 02, 2020, 03:31:27 pm
Hi,

I am not ignoring the Atik customers, I am one myself with an original Horizon so I do have skin in the game.

I have been doing electronics for over 50 years, including analogue and digital design profesionally for instrumentation as well as a few switching power supplies - mainly for HV generation for flashlamps and that sort of thing. I am more of a generalist than a hyper-focused specialist so I am perfectly aware that there are lots of things I don't know in depth or have direct experience of. I am also aware I have forgotten a lot of stuff too... what was that you were saying?

I am making the point that in CMOS that the ADC and the analogue circuitry is all on chip, so outside of Atik's control, compared to a CCD where that is all up to the designer. I am currently working on a 1Khz rep rate CCD line array spectrometer, so I am aware of the differences.

Yes, one can clearly see three switching supplies in SOT-23 packages, as well as the bigger one, in the middle of the board which power the digital sensor controller circuitry. There are also five linear regulators which I assume power the sensor. And yes, noise induced into the linear supply rails/ground could impact the ADCs and analog side as I previousl mentioned.

How is the dark-level banding showing up?

1. Does it move around, randomly on a frame by frame basis?
2. Does it move, but aligned with brighter stars or light sources?
3. Is it static and always on the same lines irrespective of the image?
4. Or... ???

I need to do some testing, but unfortunately don't have the time this weekend to do so as I have some work deadlines to deal with.

Best,
Susan.
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: atikuser on August 02, 2020, 05:02:57 pm
Susan,

Thank you for a cogent reply.  I await your further investigation and comments.

I don't own an Atik Horizon, so I can't do any electronic testing.  As I said in my initial post, I repaired a friend's Horizon which had a broken power connector.  My friend has moved away, and is now an 8-hour drive away.

Atik was less than friendly to him regarding troubleshooting and repair.  I think the power connector, and its mounting are inferior, especially if the connector tabs can be ruptured so easily. 

I have had problems with pin-and-sleeve connectors on Orion SkyView Pro mounts.  Not outright breakage, but intermittent connections that cause mount reset when the power cable gets moved.  I also had a problem with bad power connector solder joints on one of the SkyView pro mounts.

On my Orion Atlas Pro mount, the power connector is an all metal threaded-together connector, and is not disrupted when the supply cable gets pulled.

Now, all power and data connections to the mounts are through coiled cords, which are easily made by winding the cable around a 1/4" wood dowel, then heating it with hot air gun until the cable insulation just starts to get shiny, then letting it cool.  I did this modification on my friends Horizon power cable.  See photo.  The transition from coiled to straight cable is fixed to the mount leg with Velcro.

I have 61 years experience as an electrical engineer, and now have an engineering consulting business.  Like you, I have seen it all, and have experienced difficult to solve problems.

Again, I await your engineering investigation results.  I hope this problem has an easy solution.

Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: susan-parker on August 02, 2020, 09:14:12 pm
Thanks, when I get the time I will give an update.

Meanwhile I would note the same sensor is used in the ZWO ASI 1600MM/MC series:

  https://astronomy-imaging-camera.com/product/asi1600mm-cool

So probably worth looking at their forum chats to see if there has been a similar issue reported.
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: atikuser on August 03, 2020, 11:52:40 am
Susan,

Thank you for the information that the ZWO ASI 1600MM/MC camera uses the same Panasonic sensor.

Oh ZWO's forum, there also are comments about horizontal banding.

Sam, who lists his title as 'ZWO Founder' blogs 'We saw this problem sometimes and we suspect this is because of magnetic field effect caused by power supply cable'.  Moreover other bloggers relate the banding is worse when the Peltier cooler is cooling down (high current drive), and gets les when the cooler reaches set temperature.

Magnetic field coupled noise is another way of saying EMI.

Aluminum is a poor magnetic shielding material for low frequencies.  If indeed the coupled interference is coming from the power supply cable, then the aluminum camera housing is not providing enough shielding.
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: atikuser on August 13, 2020, 06:43:43 pm
nikkinemo95, interesting comment. 

You can use Photoshop's magic marker tool to separate the sky from the foreground.  You probably will have to experiment with the tolerance level.  You may have to modify the transition line, which you can do by holding down 'shift' while using the 'lasso' tool to add to the selected area, or hold down 'alt' while using the same tool to subtract from the selected area.  I generally have 'anti-alias' turned off.

How does your comment relate to horizontal banding?  Do you see horizontal banding that is related to the sky/foreground transition?

On the subject of banding, Atik might investigate what sensors Nikon and Canon use.  Their latest cameras use CMOS sensors.  I take astrophotos with either a Nikon D5200 or D500, principally the D500 now.  I have never seen banding in images taken.  Attached is a recent D500 image of M81 (30-second, iso 25600) on a C11, Orion Atlas Pro mount.  Unguided.

Atmospheric turbulence is an ever present problem.  It smears out star images from pinpoints in time exposures, as can be seen in the M81 image.
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: Moonrider on March 27, 2021, 03:03:43 am
Yep, it is not only a problem for the color sensors...
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: Noah4x4 on March 27, 2021, 07:37:36 am
I ceased using Infinity and it's Low, Medium, High presets and switched to Sharpcap Pro for EAA largely because it offered flats/darks on the fly and other advanced features. However, Infinity is great for beginners as it is so easy and Sharpcap is comparatively difficult. So please don't view my comments as criticism of Infinity.

However, using SharpCap Pro's custom exposure/gain sliders I can remove any unwelcome banding, which I also see with my ZWO ASI294, so this issue isn't unique to the Horizon.  I think it is an issue with Infinity's too narrow inflexible software presets.

So, if suffering from banding, instead use Custom Gain to find the right combination. The learning curve is steeper with custom gain settings, but I don't think there is any problem with the camera, nor with Infinity if prepared to use custom Gain.
Title: Re: Horizontal Banding - Color Horizon - Still a problem!
Post by: Moonrider on March 29, 2021, 02:35:17 am
That is my understanding too, more of an issue with the presets. I presently use custom and like you, can mostly eliminate the banding. Also it is important to have the "Even illumination" option selected.