Date   

Re: Mount Status Not Updating in MaxIm DL Observatory Control Window

Dale Ghent
 

On Nov 23, 2021, at 11:14, Brian Valente <bvalente@...> wrote:

I would just add that when I process my ASI6200 OSC files in PixInsight, each debayered file is around 850mb. That doesn't include the other interim files (calibrated, cosmetized, etc.). They are huge

I also try for the longest subs i can to reduce the number of files i have to integrate.
Ah yes, I forgot he as the color version. Yeah, debayering is going to blow that footprint up a bit earlier in the processing chain of events.


pull it out on the rare occasion that I need it, which is usually just to rip a music CD.
You still use Music CDs?? :-)
The music labels for the genres of music that I (used to) DJ for still release a bit of music on non-downloadable formats. Streaming and file downloads are by far typical now, but remixes and some limited edition tracks with art occasionally pop up only in CD or 12" EP only. Back in The Day(tm), before everyone had broadband and MP3s were still a twinkle in MPEG's eye, producers and DJs would mail or trade you a DAT or Sony Minidisc because the bandwidth of those in the first class or international postal mail was still better than dialup modem at the time :V


Re: Eltima Virtual Ports

hawkp60@...
 

Thanks for the information, Bob. The program (APCC and AP V2 Driver) was working fine on Win 11. I'm going to rule out the physical ports as an issue since it's the same computer.

David Burrell


Re: Eltima Virtual Ports

Ray Gralak
 

You can try this BETA version of APCC Pro, which has a newer version (V10) of the Eltima ActiveX control and drivers:

https://www.apastrosoftware.com/apcc_download/APCC_Pro_BETA_Setup_1.9.2.3.exe

-Ray

-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of hawkp60@...
Sent: Tuesday, November 23, 2021 8:57 AM
To: main@ap-gto.groups.io
Subject: [ap-gto] Eltima Virtual Ports

Last week I spoke with Howard about the issue with Eltima. I am posting my issue here to see if anyone else
has this issue and maybe has a work around?

I have a GTOCP5 with APCC pro version 1.9.0.11. Everything was working fine until upgrading to a new
computer that runs windows 11. APCC was working fine but I had problems with my camera driver on windows
11. I uninstalled windows 11 and installed windows 10 thinking maybe that would fix the camera issue. During
the uninstall of windows 11 all the programs were deleted and I had to download APCC Pro again. The
problem is the Eltima Virtual port software is not loading (at least that's my understanding). I have uninstalled
and reinstalled APCC Pro as late as today. The Eltima is still missing. I saw a recent post where Ray said that
the Eltima drivers were updated for v1.9.0.11 - but like I mentioned the download (v1.9.0.11) doesn't appear to
be installing Eltima. Maybe I am not understanding the difference between Eltima software and the driver.


Re: Eltima Virtual Ports

Bob Enouen
 

I had this problem on a Beelink U57 with Windows 10 Pro on my GTOCP4. It did not have any physical serial ports and that may have been the issue.  I switched to a Shuttle XPC DH 110 that had a real port and that solved it for me.

Thanks, Bob


Robert J. Enouen
Cell 513-504-4410

On Nov 23, 2021, at 11:59 AM, hawkp60@... wrote:

Last week I spoke with Howard about the issue with Eltima. I am posting my issue here to see if anyone else has this issue and maybe has a work around?

I have a GTOCP5 with APCC pro version 1.9.0.11. Everything was working fine until upgrading to a new computer that runs windows 11. APCC was working fine but I had problems with my camera driver on windows 11. I uninstalled windows 11 and installed windows 10 thinking maybe that would fix the camera issue.  During the uninstall of windows 11 all the programs were deleted and I had to download APCC Pro again. The problem is the Eltima Virtual port software is not loading (at least that's my understanding). I have uninstalled and reinstalled APCC Pro as late as today. The Eltima is still missing. I saw a recent post where Ray said that the Eltima drivers were updated for v1.9.0.11 - but like I mentioned the download (v1.9.0.11) doesn't appear to be installing Eltima. Maybe I am not understanding the difference between Eltima software and the driver.  


Re: APPM Will Not Connect to NINA Camera

Sébastien Doré
 

Interesting. I don't know what could've happened. I don't use any "cleaning" software on any of my PC (unless Win10 has one built-in that I am not aware of).

Besides, I just tried upgrading from beta 4 to 6 and indeed it stayed enabled this time around. 

I didn't report that issue at the time because, well, it was a very minor one (once cause was known) and I figured I'd stay more on known ground (not upgrading) for a while as I have less and less clear nights to test at this time of year.

Anyway, thanks for the insight Dale. Hope this helps the OP too.


De : main@ap-gto.groups.io <main@ap-gto.groups.io> de la part de Dale Ghent <daleg@...>
Envoyé : 23 novembre 2021 11:48
À : main@ap-gto.groups.io <main@ap-gto.groups.io>
Objet : Re: [ap-gto] APPM Will Not Connect to NINA Camera
 

The Enable Server setting (and a few other things that need to get loaded early after app launch, such as font selection, etc) is stored as a Windows/.NET application level setting and not as part of the active NINA profile, which gets loaded in much later.

The app settings file itself is in %LOCAPPDATA%\NINA, where you'll find a subdirectory called "NINA.exe_<hash>", and in there will be a user.config XML file. If that subfolder and file get wiped, perhaps by a utility that tries to be "helpful" and cleans up after uninstalled apps, then that can be a reason why settings don't get migrated across an upgrade.


Eltima Virtual Ports

hawkp60@...
 

Last week I spoke with Howard about the issue with Eltima. I am posting my issue here to see if anyone else has this issue and maybe has a work around?

I have a GTOCP5 with APCC pro version 1.9.0.11. Everything was working fine until upgrading to a new computer that runs windows 11. APCC was working fine but I had problems with my camera driver on windows 11. I uninstalled windows 11 and installed windows 10 thinking maybe that would fix the camera issue.  During the uninstall of windows 11 all the programs were deleted and I had to download APCC Pro again. The problem is the Eltima Virtual port software is not loading (at least that's my understanding). I have uninstalled and reinstalled APCC Pro as late as today. The Eltima is still missing. I saw a recent post where Ray said that the Eltima drivers were updated for v1.9.0.11 - but like I mentioned the download (v1.9.0.11) doesn't appear to be installing Eltima. Maybe I am not understanding the difference between Eltima software and the driver.  


Re: APPM Will Not Connect to NINA Camera

Dale Ghent
 

The Enable Server setting (and a few other things that need to get loaded early after app launch, such as font selection, etc) is stored as a Windows/.NET application level setting and not as part of the active NINA profile, which gets loaded in much later.

The app settings file itself is in %LOCAPPDATA%\NINA, where you'll find a subdirectory called "NINA.exe_<hash>", and in there will be a user.config XML file. If that subfolder and file get wiped, perhaps by a utility that tries to be "helpful" and cleans up after uninstalled apps, then that can be a reason why settings don't get migrated across an upgrade.

On Nov 23, 2021, at 11:20, Sébastien Doré <sebastiendore1@...> wrote:

In NINA, did you go to Options > General and turn on Enable Server? This turns on the API service that APPM must use to access the camera via NINA.

I had the same "problem" and have found that in recent NINA 1.11 updates, that specific setting isn't stored in the profile anymore or at least seem to be reset to default (=disabled) with each re-install even without uninstallling NINA first.

I don't recall having to do so with every update when I first started using NINA last summer. I suppose there's a reason for that but haven't inquire about it on the NINA discord.



Re: Mount Status Not Updating in MaxIm DL Observatory Control Window

W Hilmo
 

It's actually a bit rare for computers to be replaced due to failure.  Most of the time, it's due to obsolescence.  And most of the failure cases that do occur, like yours, are due to some kind of damage.

I have two rules of thumb for replacing computers.  They apply to both desktops and laptops:

1) There is a price to performance curve.  You can get generally get low performance machines quite cheaply.  These are good for email, browsing, etc., but not so much for gaming.  In terms of astronomy, cheap machines are good for image capture, but not so much for processing, with the caveat that if you are doing anything with video (planetary imaging), the performance requirements climb rapidly with larger sensors.  To get the maximum performance, you will spend a whole lot of money.  But the curve is not linear.  There tends to be a place where you can get most of the performance for significantly less cost than the top of the line.  For most uses, I like to shop at the point in the curve where the price just starts to climb rapidly.

2) I start thinking about replacing a machine when the machines in that sweet spot are 4x to 5x faster than the machine that they are replacing.

That is the strategy that I've used for the last 20 years.  I have to admit, though, that it may need some updating.  The reaspon is that computers are getting very, very fast for most tasks.  An older machine that is 4x slower than the current "sweet spot" may still have plenty of horsepower for most tasks.  Now that I am retired, I'm much less likely to replace a computer just because it's old.  Lately, I find that I don't give any thought to replacing a machine that's doing its job well.  Once I notice that a computer needs my attention, that's when I apply the two above rules of thumb.

Specifically for image processing, I'm migrating away from laptops.  Until fairly recently, my most used machine was a Dell XPS 13 with 16GB of RAM, a 1 TB SSD and the fastest Core i7 processor that was offered at the time.  It was running Windows 10.  I used this machine for everything.  At my desk, I docked it so that it had a regular keyboard and mouse, plus 3 monitors.  I recently added a new desktop machine.  It's a Dell OptiPlex 7080, purchased using the above rules for about 30% of the cost of the current top line mini desktops.  It's got one generation back Core i7, 32GB of RAM and a 1TB SSD.  Instead of Windows, I have moved to Linux for my desktop.  This new machine runs PixInsight much more efficiently than the laptop did.  I keep the laptop for exclusively portable use.  I still do image processing on it when I am out at dark sky sites, but the new desktop works much better.

Oh, and I would add that the 1TB drives are too small to be my only storage.  I tend to just keep active projects stored on the SSD's.  I have a NAS at home for long term storage.  It's currently got 12 TB of storage.  When that gets to be insufficient, I'll either upgrade the drives to larger ones, or (more likely) add a second NAS.

-Wade

On 11/22/21 7:51 PM, Roland Christen via groups.io wrote:
At Ray's suggestion I plugged the mount into a USB socket on one side of the laptop and the camera into the opposite side (USB ports separated). That seemed to have fixed the issue. Normally I plug them in to the 2 adjacent USB ports, and that's where the trouble occurs.

I plan to get a new laptop now that I have hosed this one in the rainstorm. Any suggestions for a laptop that can process the ZWO 6200 full frame color images that are of enormous size? Right now the laptop cannot combine more than 4 of them before giving up the ghost. Not enough memory apparently.

Rolando



-----Original Message-----
From: M Hambrick <mhambrick563@...>
To: main@ap-gto.groups.io
Sent: Mon, Nov 22, 2021 8:19 pm
Subject: Re: [ap-gto] Mount Status Not Updating in MaxIm DL Observatory Control Window

I finally got to test my system outdoors last Friday night to see if I could duplicate the original problems that I experienced on November 8 when the mount status and position stopped communicating to MaxIm DL, locking everything up.

I had everything set up the same way as I did for my previous indoor test. I put the mount through several slews to different objects with no issues. At each object I started autoguiding with the guide camera while taking images through the main imaging camera. I took several autosave sequences as well as a number of individual images. Throughout the evening everything behaved normally.

I have run out of ideas for things to check, so for now I will just assume that it was some kind of anomaly.

Mike

--
Roland Christen
Astro-Physics


Re: APPM Will Not Connect to NINA Camera

ap@CaptivePhotons.com
 

Sébastien Doré wrote:

 

In NINA, did you go to Options > General and turn on Enable Server? This turns on the API service that APPM must use to access the camera via NINA.

 

  • I had the same "problem" and have found that in recent NINA 1.11 updates, that specific setting isn't stored in the profile anymore or at least seem to be reset to default (=disabled) with each re-install even without uninstallling NINA first.

 

  • I don't recall having to do so with every update when I first started using NINA last summer. I suppose there's a reason for that but haven't inquire about it on the NINA discord.

Are you sure it was the same profile?

 

We are on 2.0 Beta 06 now, and I just did that update and checked before and after and my server enabled setting is still on.

 

Next time you update please double check, I suggest if it fails raise it as an issue on Discord or Bitbucket.

 

Linwood

 


Re: APPM Will Not Connect to NINA Camera

Bob Enouen
 

Awesome - that fixed it!

Thanks, Bob


Robert J. Enouen
Cell 513-504-4410

On Nov 23, 2021, at 11:07 AM, Dale Ghent <daleg@...> wrote:


In NINA, did you go to Options > General and turn on Enable Server? This turns on the API service that APPM must use to access the camera via NINA.


On Nov 23, 2021, at 10:58, renouen@... wrote:

Hi All!

First post from a newbie, but I've been following these helpful posts for a few weeks. I had my first successful imaging session last night with my observatory based RC 16" / AP1600 non-encoder / ASI 6200MM setup on 120 second subs unguided. I was hoping to taking it to the next level by adding an APPM file, but got ejected from the program each time I tried to connect APPM to the Camera with NINA selected. I'm able to plate solve in NINA directly and the 6200MM is working fine so I figure I must have missed some selection in APPC or APPM. I'm using the latest Beta NINA and the latest APCC Pro. Here are a couple of screen shots on the setup and the error report that shuts down the program. Any advice would be appreciated!

Bob

<2021-11-23 _3_.png><2021-11-23.png>





Re: APPM Will Not Connect to NINA Camera

Sébastien Doré
 

In NINA, did you go to Options > General and turn on Enable Server? This turns on the API service that APPM must use to access the camera via NINA.

I had the same "problem" and have found that in recent NINA 1.11 updates, that specific setting isn't stored in the profile anymore or at least seem to be reset to default (=disabled) with each re-install even without uninstallling NINA first.

I don't recall having to do so with every update when I first started using NINA last summer. I suppose there's a reason for that but haven't inquire about it on the NINA discord.



Re: Mount Status Not Updating in MaxIm DL Observatory Control Window

 

I would just add that when I process my ASI6200 OSC files in PixInsight, each debayered file is around 850mb. That doesn't include the other interim files (calibrated, cosmetized, etc.). They are huge

I also try for the longest subs i can to reduce the number of files i have to integrate.



>>>pull it out on the rare occasion that I need it, which is usually just to rip a music CD.

You still use Music CDs?? :-)



On Tue, Nov 23, 2021 at 8:05 AM Dale Ghent <daleg@...> wrote:


Taking your 16200 chip, 4500x3600 pixels = 16,200,000 pixels at 16 bits per pixel. That's 32.4MB of pixel data, or 30.8 Mebibytes. Add in another however little bit more for header data, and you arrive at your observed 30.9MiB file size.

For Roland's ASI6200, that's ~61 million 16 bit pixels. That's 122MB, or 116MiB of pixel data per image. Capturing these kinds of images doesn't take much, just hdd/ssd storage. Processing them requires a large working set in memory which, in practical terms, means a system with 16GB (or more) of memory to be comfortable.

Laptops can last for quite a long time on average and seeing a consumer-grade one kicking around after 8 years is not uncommon provided it's not used as a frisbee. The reason why companies tend to refresh their fleets of devices every 3-5 years is because that's how long the typical service contract and warranties last, and maintaining 5 year old models that are used daily takes more effort and toil than it would for a new system.

USB port count has tended to stay the same across the same model lines, and I think in some cases has gone up as the move to USB-C has afforded more physical space to fit additional ports. My 2019 MacBook Pro has 4x USB-C ports where my previous MBP had 3x USB-A ports. USB-C also has brought a wider adoption of "docking hub" style accessories, where a small, compact box that has power, video, ethernet, oodles of USB ports, and even SD card readers will connect to the laptop with a single cable, a cable that carries both data and high wattage power to the laptop.

If I need a CDROM drive, I keep a USB one squirreled away in a drawer and pull it out on the rare occasion that I need it, which is usually just to rip a music CD. I see no reason for these to continue to be integrated into laptops where they only add bulk to the thing for only occasional use; plus they're mechanical animals and thus prone to breaking on their own. It's much easier to sell off a working laptop without a CD drive vs. selling one that works but has a broken CD drive.

> On Nov 23, 2021, at 09:34, M Hambrick <mhambrick563@...> wrote:
>
> Great question about laptop specs Roland.
>
> The FITS subframe images from my STXL16200 camera are each 30.9MB, and the stacked LRGB images are 185 MB. What size are the images from your ZWO camera ?
>
> What is the typical life expectancy of a laptop (or any) computer these days ? That is assuming that it has not been damaged. When I was still working they used to replace our company laptops about every 3 - 5 years. My personal laptop is an ASUS Q552U that I bought at the end of 2015. I wanted to find a laptop that had a built-in CD-ROM, and this was one of the only models that had one. It's got the Intel I7 core with 12GB RAM and a 1TB hard drive. I have had pretty good luck with it for imaging and processing, but I have never tried to process a really large stack of images.
>
> I have noticed lately that they are not putting very many USB ports in the new model laptops.
>
> Mike
>








--
Brian 



Brian Valente


Re: APPM Will Not Connect to NINA Camera

Dale Ghent
 

In NINA, did you go to Options > General and turn on Enable Server? This turns on the API service that APPM must use to access the camera via NINA.

On Nov 23, 2021, at 10:58, renouen@... wrote:

Hi All!

First post from a newbie, but I've been following these helpful posts for a few weeks. I had my first successful imaging session last night with my observatory based RC 16" / AP1600 non-encoder / ASI 6200MM setup on 120 second subs unguided. I was hoping to taking it to the next level by adding an APPM file, but got ejected from the program each time I tried to connect APPM to the Camera with NINA selected. I'm able to plate solve in NINA directly and the 6200MM is working fine so I figure I must have missed some selection in APPC or APPM. I'm using the latest Beta NINA and the latest APCC Pro. Here are a couple of screen shots on the setup and the error report that shuts down the program. Any advice would be appreciated!

Bob

<2021-11-23 _3_.png><2021-11-23.png>


Re: Mount Status Not Updating in MaxIm DL Observatory Control Window

Dale Ghent
 

Taking your 16200 chip, 4500x3600 pixels = 16,200,000 pixels at 16 bits per pixel. That's 32.4MB of pixel data, or 30.8 Mebibytes. Add in another however little bit more for header data, and you arrive at your observed 30.9MiB file size.

For Roland's ASI6200, that's ~61 million 16 bit pixels. That's 122MB, or 116MiB of pixel data per image. Capturing these kinds of images doesn't take much, just hdd/ssd storage. Processing them requires a large working set in memory which, in practical terms, means a system with 16GB (or more) of memory to be comfortable.

Laptops can last for quite a long time on average and seeing a consumer-grade one kicking around after 8 years is not uncommon provided it's not used as a frisbee. The reason why companies tend to refresh their fleets of devices every 3-5 years is because that's how long the typical service contract and warranties last, and maintaining 5 year old models that are used daily takes more effort and toil than it would for a new system.

USB port count has tended to stay the same across the same model lines, and I think in some cases has gone up as the move to USB-C has afforded more physical space to fit additional ports. My 2019 MacBook Pro has 4x USB-C ports where my previous MBP had 3x USB-A ports. USB-C also has brought a wider adoption of "docking hub" style accessories, where a small, compact box that has power, video, ethernet, oodles of USB ports, and even SD card readers will connect to the laptop with a single cable, a cable that carries both data and high wattage power to the laptop.

If I need a CDROM drive, I keep a USB one squirreled away in a drawer and pull it out on the rare occasion that I need it, which is usually just to rip a music CD. I see no reason for these to continue to be integrated into laptops where they only add bulk to the thing for only occasional use; plus they're mechanical animals and thus prone to breaking on their own. It's much easier to sell off a working laptop without a CD drive vs. selling one that works but has a broken CD drive.

On Nov 23, 2021, at 09:34, M Hambrick <mhambrick563@...> wrote:

Great question about laptop specs Roland.

The FITS subframe images from my STXL16200 camera are each 30.9MB, and the stacked LRGB images are 185 MB. What size are the images from your ZWO camera ?

What is the typical life expectancy of a laptop (or any) computer these days ? That is assuming that it has not been damaged. When I was still working they used to replace our company laptops about every 3 - 5 years. My personal laptop is an ASUS Q552U that I bought at the end of 2015. I wanted to find a laptop that had a built-in CD-ROM, and this was one of the only models that had one. It's got the Intel I7 core with 12GB RAM and a 1TB hard drive. I have had pretty good luck with it for imaging and processing, but I have never tried to process a really large stack of images.

I have noticed lately that they are not putting very many USB ports in the new model laptops.

Mike


APPM Will Not Connect to NINA Camera

Bob Enouen
 

Hi All!

First post from a newbie, but I've been following these helpful posts for a few weeks.  I had my first successful imaging session last night with my observatory based RC 16" / AP1600 non-encoder / ASI 6200MM setup on 120 second subs unguided.  I was hoping to taking it to the next level by adding an APPM file, but got ejected from the program each time I tried to connect APPM to the Camera with NINA selected.  I'm able to plate solve in NINA directly and the 6200MM is working fine so I figure I must have missed some selection in APPC or APPM. I'm using the latest Beta NINA and the latest APCC Pro.  Here are a couple of screen shots on the setup and the error report that shuts down the program.  Any advice would be appreciated!

Bob


Re: [ap-ug] Leo Galaxy Tour

Pete Lardizabal
 

Nice snapshots Roland!

👍🏻👍🏻👍🏻

Pete

On Nov 22, 2021, at 10:46 PM, Roland Christen via groups.io <chris1011@...> wrote:


Hello Astronuts,

While visiting Hawaii in the spring of last year I had a few clear nights and did a galaxy tour in Leo. Here are some of the images. All were short exposures, snapshots if you will, and I was mainly concentrating in resolving the cores of these galaxies at the expense of the deeper field. Thus the short exposures of 300 to 600 seconds in order to prevent saturating the cores and blowing up the detail. I only had a few days that were suitable for imaging these cool galaxies. All were taken with the 175 EDF on the 1600 Encoder mount, unguided.

https://www.astrobin.com/um0g02/
https://www.astrobin.com/fwk2ce/
https://www.astrobin.com/g34h6r/
https://www.astrobin.com/aj8xuq/

They are in my staging area, I'm too embarrassed to show them to the rest of the Astrobin crowd Grin

Rolando


Re: Upgrade to APCC Pro 1.9.0.11

Ray Gralak
 

Ray, I assume if I have version 1.9.0.11, it is not necessary to uninstall first. Correct?
Larry, I am not sure what you mean. If you already have 1.9.0.11 installed, then you don't need to uninstall and reinstall it.

-Ray


Re: Mount Status Not Updating in MaxIm DL Observatory Control Window

M Hambrick
 

Great question about laptop specs Roland.

The FITS subframe images from my STXL16200 camera are each 30.9MB, and the stacked LRGB images are 185 MB. What size are the images from your ZWO camera ? 

What is the typical life expectancy of a laptop (or any) computer these days ? That is assuming that it has not been damaged. When I was still working they used to replace our company laptops about every 3 - 5 years. My personal laptop is an ASUS Q552U that I bought at the end of 2015. I wanted to find a laptop that had a built-in CD-ROM, and this was one of the only models that had one. It's got the Intel I7 core with 12GB RAM and a 1TB hard drive. I have had pretty good luck with it for imaging and processing, but I have never tried to process a really large stack of images. 

I have noticed lately that they are not putting very many USB ports in the new model laptops.

Mike


Re: Upgrade to APCC Pro 1.9.0.11

Larry Phillips
 

Ray, I assume if I have version 1.9.0.11, it is not necessary to uninstall first. Correct?
Larry


Re: Leo Galaxy Tour

Howard Ritter
 

Detail in dust lanes that would do credit to a scope of only 2 or 3 times the aperture, not 10x? Yeah, I feel your embarrassment!

The NGC 2903/2905 designations are interesting. I don’t think I’ve ever seen the NGC (wrongly) designate a feature in a galaxy as a second galaxy in its own right. The visual observations on which the catalog was based evidently didn’t go deep enough to show both the nucleus and the knot of 2903 as part of a single galaxy, and the observer took them for the nuclei of two galaxies.

Thanks for posting. They’re very elegant images.

—howard

On Nov 22, 2021, at 10:46 PM, Roland Christen via groups.io <chris1011@...> wrote:

Hello Astronuts,

While visiting Hawaii in the spring of last year I had a few clear nights and did a galaxy tour in Leo. Here are some of the images. All were short exposures, snapshots if you will, and I was mainly concentrating in resolving the cores of these galaxies at the expense of the deeper field. Thus the short exposures of 300 to 600 seconds in order to prevent saturating the cores and blowing up the detail. I only had a few days that were suitable for imaging these cool galaxies. All were taken with the 175 EDF on the 1600 Encoder mount, unguided.


They are in my staging area, I'm too embarrassed to show them to the rest of the Astrobin crowd Grin

Rolando

--
Roland Christen
Astro-Physics

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