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core
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iPhone 'SQM' app available soon ... your thots?
      #5692565 - 02/21/13 11:32 AM

Came across this soon-to-be-released app for iPhone - Dark Sky Meter.

Their reasoning being that they are coding and calibrating for a only a couple of devices (4/4s, 5?), it should work reasonably well. Does iOS allow for complete control of the camera h/w? I presume setting the focus point to an arbitrary 'near' to spread out the incoming light, and having complete control of the camera's exposure/gain settings is along the lines of standardizing a reading.

fwiw, for comparison:

SQM FOV for HWHM is 42
SQM-L FOV for HWHM is 10
iPhone 4 FOV ~60x47
iPhone 4s FOV ~56x43

No relation to the app or anyone involved, just very curious; if it works it would be a great app/equipment, and the sudden jump in crowd-sourced 'SQM' reading would be fantastic.


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wolfman_4_ever
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: core]
      #5692779 - 02/21/13 01:37 PM

I have a Unihedron SQM... I'll have to compare when the app comes out..

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microstar
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: wolfman_4_ever]
      #5692817 - 02/21/13 01:55 PM

Looks interesting! I'll be following this one. Thanks for posting.
...Keith


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Raginar
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: microstar]
      #5692879 - 02/21/13 02:37 PM

When is it going to be available? Only SQM app I found was a controller for some other one.

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hbanich
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Raginar]
      #5693034 - 02/21/13 04:12 PM

Sounds interesting but my initial thought is that looking at the screen of the iPhone, even with its screen as dim as possible, and with a red cover, will involve some loss of dark adaptation. That's one of the reasons I like the Unihedron SQM - one only has to look at the illuminated readings, not a full screen.

But my reservations are only imagined at this point and the app may have taken care of all this so I'm eager to see what it's really like.


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GlennLeDrew
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: hbanich]
      #5694021 - 02/22/13 04:47 AM

My concern is this. Can these cameras obtain an image of a fairly dark sky which is not mostly noise? The chip's pixels are awfully small, and moreover are reduced in efficiency because of the Bayer mask. One must have some minimum signal to noise ratio in order to derive a meaningful measurement allowing to discriminate brightness differences to the desired degree.

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ahopp
sage


Reged: 05/24/12

Re: iPhone 'SQM' app available soon ... your thots? new [Re: GlennLeDrew]
      #5694087 - 02/22/13 06:56 AM

I wonder if they might be binning the chip with a lot of pixels. Maybe 50x50 or more. This might do it.

Tony


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Chucky
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: ahopp]
      #5694092 - 02/22/13 07:03 AM

Wonder if this will be more of a gimmick? In the meantime, I'll just peer skyward with my good old eyes to estimate magnitude and compare results with my astro buddies. KISS principle.

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johnpd
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Reged: 04/13/08

Re: iPhone 'SQM' app available soon ... your thots? new [Re: core]
      #5695011 - 02/22/13 03:41 PM

I have been testing the app. As of the last test I ran a few days ago, it's results are under what the SQM gives you. The developer says that there is a difference between what the iPhone4 and iPhone5 camera gives you. Hopefully this evening I can try the latest release to see if its results are more consistent with the SQM.

JohnD


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starrancher
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: johnpd]
      #5695091 - 02/22/13 04:23 PM

What is a "thots" ?

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Jason D
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Chucky]
      #5695232 - 02/22/13 05:30 PM

Quote:

Wonder if this will be more of a gimmick? In the meantime, I'll just peer skyward with my good old eyes to estimate magnitude and compare results with my astro buddies. KISS principle.




Well-said

After all, these days there is an app for everything including an app for a mirror -- referring to the one that shuts off the screen so you can see your reflection.

Maybe I should consider an app for collimation!!!


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Raginar
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Jason D]
      #5695249 - 02/22/13 05:40 PM

Jason,

A collimation app would be kind of neat. You could have circles for the various rings and just line them up visually. No guess work involved?


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GlennLeDrew
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Raginar]
      #5695302 - 02/22/13 06:02 PM

Of greater interest to me is not the fact that currently this app is "under" the SQM reading, which I presume to mean is a consistently lower (brighter?) reported value, but whether the readings track reasonably closely. And whether the level of discrimination is reasonably fine. And whether the readings are reasonably repeatable. And whether results extend to at least moderately dark sky levels.

Down to about 21 MPSAS, to be useful at all the 1-sigma error should not exceed 0.2 magnitude.


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BPO
sage


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Loc: South Island, NZ
Re: iPhone 'SQM' app available soon ... your thots? new [Re: Jason D]
      #5695338 - 02/22/13 06:22 PM

Without specifically addressing the quality of the iPhone app, I would like to mention that SQM are used for many reasons. My observatory uses two SQM-LE for full-time monitoring purposes; To provide info on current conditions to active observers, and also for generating long-term records.

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Chucky
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: BPO]
      #5696113 - 02/23/13 06:46 AM

<< Maybe I should consider an app for collimation!!! >>

Seriously Jason, you really, really should consider this. It would be a great way to share your knowledge. I'll look for it on ITunes soon.


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Nop
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Chucky]
      #5708640 - 03/02/13 11:46 AM

We are developing the app. The app will hit the app store as soon as all devices with a decent camera are supported. The devices with good (close) results are the iPhone 4S and 5. We hope to support the 4's camera as well as the iPad 3rd gen and iPad mini cameras. We are working close with the IDA and will distribute a special 'lite' version soon. The lite version works like a SQM, but has not the Mag/square sec arc scale. It will be more aimed towards a broad audience, submitting as many readings as possible. This should (hopefully) generate a lot of useful readings. The app is more than a reader: it submits device position (aimed at the zenit), GPS and moon readings.
For amateur astronomers like you there will be a pro version (in app or separate build) with proper SQM readings, google like darkness map (pinpoints of you and other dark sky meter user with SQM readings) and a GFS based clear sky clock.
Currently we are testing and getting close to releasing the app. Hopefully in April.


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Raginar
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Nop]
      #5708653 - 03/02/13 11:55 AM

Norbert,

That sounds like a really good app that'll have great effects on reducing light pollution. I can't wait to try it out.


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johnpd
sage


Reged: 04/13/08

Re: iPhone 'SQM' app available soon ... your thots? new [Re: Nop]
      #5709790 - 03/03/13 12:29 AM

Hi Norbert,

I tried running a test from inside a closet but the SQM would not give me a reading. Guess it was too dark.

The latest results seem to be getting closer on my iPhone 5. Keep up the good work.

JohnD


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core
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Reged: 02/23/08

Loc: Mostly in Norman, OK
Re: iPhone 'SQM' app available soon ... your thots? new [Re: johnpd]
      #5709891 - 03/03/13 02:59 AM

Norbert,

Thanks for chiming in, and developing the app! If it isn't too much trouble or leaking 'programming secrets', could you share some insights into how you might have overcome some of the perceived issues using a iPhone's camera to do the work? I'm a little weary if the eventual results is subject to larger-than-expected variations due to iPhone H/W and iOS constraints/limitations, and all the data being fed to IDA ends up being affected.


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James Cunningham
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: core]
      #5710071 - 03/03/13 08:00 AM

What is "SQM"
Thanks.


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ahopp
sage


Reged: 05/24/12

Re: iPhone 'SQM' app available soon ... your thots? new [Re: James Cunningham]
      #5710106 - 03/03/13 08:21 AM

Sky Quality Meter

Tony


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csa/montana
Den Mama
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Raginar]
      #5710202 - 03/03/13 09:36 AM

Quote:

Norbert,

That sounds like a really good app that'll have great effects on reducing light pollution. I can't wait to try it out.




How will this app have great effects on reducing light pollution? It won't affect those that don't care about the night skies, and have bright yard lights, etc.; nor city light pollution. Just curious as to how this might benefit in reducing LP.


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ahopp
sage


Reged: 05/24/12

Re: iPhone 'SQM' app available soon ... your thots? new [Re: csa/montana]
      #5710237 - 03/03/13 09:53 AM

Awareness...

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csa/montana
Den Mama
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: ahopp]
      #5710360 - 03/03/13 10:54 AM

Sadly, I doubt a SQM appt will have very little impact on LP; those that will use it, are already aware of LP.

However, it will be a great addition for astronomers, if it's accurate!


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Raginar
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: csa/montana]
      #5710387 - 03/03/13 11:02 AM

Ahopp,

I agree. It allows me to gather data that I can put into a coherent product for the masses. For instance, I could ask to have the streetlights turned off in my neighborhood, gather some data using this tool, then get the same data points (using GIS systems) with the lights on to demonstrate what an effect it has on my skies. In addition, just from a 'neighbor' standpoint, I can show them what an effect leaving on a giant flood light has on my skies too.

You're right, the app won't magically reduce light pollution. But, it gives you easy access to data that can be used to aid the cause. And, if the app is priced right, it'll give us access to many more data points than we've had easy access to in the past. Finally, I'm assuming it's tied into some IDA database. This allows the IDA to gather local decentralized data from anyone with an Android/iOS device. That's a huge number of people these days. Even if you take into account AA's are a small number of those people, I guarantee you that the majority of us are using smart phones... ready access to volunteers to collect data is nice.

Anyways, that's where I was going with that. What do you think?


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csa/montana
Den Mama
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Raginar]
      #5710551 - 03/03/13 12:28 PM

Quote:

You're right, the app won't magically reduce light pollution. But, it gives you easy access to data that can be used to aid the cause. And, if the app is priced right, it'll give us access to many more data points than we've had easy access to in the past. Finally, I'm assuming it's tied into some IDA database. This allows the IDA to gather local decentralized data from anyone with an Android/iOS device. That's a huge number of people these days. Even if you take into account AA's are a small number of those people, I guarantee you that the majority of us are using smart phones... ready access to volunteers to collect data is nice.




Clarifying it in this manner, I agree!


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core
Pooh-Bah
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Chucky]
      #5710592 - 03/03/13 12:48 PM

Quote:

Wonder if this will be more of a gimmick? In the meantime, I'll just peer skyward with my good old eyes to estimate magnitude and compare results with my astro buddies. KISS principle.




The key here is 'estimate'; the SQM gives a repeatable, quantitative measure. And while it is related to how deep a magnitude you can see, it mainly measures the overall 'glow' of the sky. KISS is fine and well (and free!), and I've logged visual magnitude estimation for years, but a SQM reading is much more granular and objective - whether it's useful or something that perks your interest all depends on the individual.


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Jeff Morgan
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Raginar]
      #5710806 - 03/03/13 02:57 PM

When observing from the house I notice that around 11 PM the sky starts getting better, presumably as people go to bed and start shutting down lighting. One could take readings during the night to show this, and extrapolate to what could happen if the big and unneeded light sources could be shut down.

I think it will also be useful to compare observing sites on a relative basis.


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johnpd
sage


Reged: 04/13/08

Re: iPhone 'SQM' app available soon ... your thots? new [Re: Nop]
      #5711771 - 03/03/13 11:54 PM

Hi Norbert,

I tried several from a dark room inside the house. I got a number of "Invalid, Retry" errors. The skies may clear later on. Will try again outside.

JohnD


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CharlesW
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: johnpd]
      #5711803 - 03/04/13 12:29 AM

Unfortunately municipalities will not turn off street lights on a wholesale basis. Too much liability after some knucklehead kills themselves on a road and their family sues the city/county because the road was "unsafe". There are whole divisions set up to handle exactly these issues.

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Nop
Vendor (iPushto)


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Re: iPhone 'SQM' app available soon ... your thots? new [Re: CharlesW]
      #5712007 - 03/04/13 07:15 AM Attachment (15 downloads)

We made great progress with our Dark Sky Meter app. The iPhone 4S and Unihedron SQM are on par. We are finalizing the 5. Next up will be the iPhone 4 and iPads.

The pro version has a (cached!) live map view containing all valid SQM readings made by the app users worldwide.
The app uses 'facebook' style navigation.

@core
We started testing with the 4S and the results were that close to a SQM (with the SQM sometimes more 'jumpy' than the 4S)that we decided to continue the project. At daytime i am working on a spectroscopy app for the astronomy department of the Leiden University. So i'm getting an expert on iPhone sensors


@JohnPD, thanks for Testing, currently we are evaluating the results.

Edited by Nop (03/04/13 07:16 AM)


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JMW
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Reged: 02/11/07

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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Nop]
      #5712751 - 03/04/13 03:36 PM

I like the crowd sourcing potential for updating light pollution maps. It would also be a great awareness tool.

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Jeff Morgan
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: CharlesW]
      #5712796 - 03/04/13 03:59 PM

Quote:

Unfortunately municipalities will not turn off street lights on a wholesale basis. Too much liability after some knucklehead kills themselves on a road and their family sues the city/county because the road was "unsafe". There are whole divisions set up to handle exactly these issues.




It would be rather interesting to plot vehicle injury accidents and fatalities by road type. My guess is that most of the incidents are on roads already made "safe" by streetlights.


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GlennLeDrew
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Jeff Morgan]
      #5712932 - 03/04/13 05:04 PM

Testing light meters indoors with the lights off can often result in conditions rather darker than a clear, dark sky. You might be surprised at how bright your room must be made to equal, say, a 21 MPSAS semi-rural sky!

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johnpd
sage


Reged: 04/13/08

Re: iPhone 'SQM' app available soon ... your thots? new [Re: Nop]
      #5715734 - 03/06/13 01:26 AM

Hi Norbert,

We are clouded out tonight. Will resume testing Wednesday evening.

JohnD


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derangedhermit
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: johnpd]
      #5720303 - 03/08/13 11:10 AM

With the wide field of view, how do you account for the brightness of the Milky Way (or lack of same) in the field?

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Jeff Morgan
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: derangedhermit]
      #5720751 - 03/08/13 03:53 PM

Quote:

With the wide field of view, how do you account for the brightness of the Milky Way (or lack of same) in the field?




Perhaps the answer is to narrow the field.


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Raginar
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: James Cunningham]
      #5721117 - 03/08/13 08:13 PM

Jimmy,

Sky Quality Measurement. There is a manufacturer of similar devices... I think people use them to determine where it's worth imaging .


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Madratter
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Raginar]
      #5721299 - 03/08/13 10:08 PM

I'm sure hoping this will work not just on the I-phone 4 and 5 but at least the SQM part on the I-pod touch 4 and 5. I don't even care all that much if it is calibrated for it. I just want an objective measure of how good it is out any particular night. For some reason, I often can see down to about the same NELM on nights where I am pretty sure the amount of light in the sky really is quite different.

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Raginar
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Madratter]
      #5721327 - 03/08/13 10:29 PM

Madratter, I agree.

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johnpd
sage


Reged: 04/13/08

Re: iPhone 'SQM' app available soon ... your thots? new [Re: derangedhermit]
      #5721552 - 03/09/13 03:05 AM

Quote:

With the wide field of view, how do you account for the brightness of the Milky Way (or lack of same) in the field?




I know the Milky Way affects the values on my SQM. Readings give a brighter result.

JohnD


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core
Pooh-Bah
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Madratter]
      #5721633 - 03/09/13 04:39 AM

Quote:

I don't even care all that much if it is calibrated for it. I just want an objective measure




fwiw, to get a objective measurement will require a calibrated reading; an un-calibrated reading gets you subjective reading - if using the same device, then you can get a subjective night-to-night difference in reading, but you can't give it an objective visual magnitudes per square arcsecond.


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dan777
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: core]
      #5721924 - 03/09/13 10:06 AM

Quote:

an un-calibrated reading gets you subjective reading - if using the same device, then you can get a subjective night-to-night difference in reading



Not really. If you have an instrument with good repeatability but a DC offset, you will get objective data. As long as you don't care about absolute accuracy, you can use it to compare tonight's sky with last night's sky and get objective data. Using your naked eye to compare tonight's sky with last night's sky will give you subjective data.

BTW, thanks for the heads-up on this app.


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core
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: dan777]
      #5722165 - 03/09/13 12:00 PM

Might be a matter of semantics on my end , but say if a measuring tape is off by +0.5", I couldn't measure my mirror and say objectively that my mirror is 8.5" diameter (and likewise "my SQM reading at my backyard was 19.9 last night"). There might be the issue of linearity as well, perhaps something on the hardware end (gain/AGC) that imposes a non-linear transfer function.

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Madratter
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: core]
      #5724649 - 03/10/13 08:04 PM

I think there is some confusion going on here between accuracy, precision, and objectivity.

Objective would normally mean that the reading does not depending on the person using the tool.

http://wiki.answers.com/Q/What_is_the_meaning_of_the_scientific_word_objective

"Scientific objectivity means that independent observers, using the same procedures, will come to consensus regarding the phenomenon they are studying. In other words, personal opinions, values, and biases will not change observations recorded with scientific objectivity."

Precision is how many digits are reported in a measurement.

Accuracy is how much error there is in a measurement.

In this case, I want the app as long as it is objective and repeatable, even if it isn't particularly accurate.


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derangedhermit
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: johnpd]
      #5725178 - 03/11/13 03:27 AM

Quote:

Quote:

With the wide field of view, how do you account for the brightness of the Milky Way (or lack of same) in the field?




I know the Milky Way affects the values on my SQM. Readings give a brighter result.

JohnD



Yes, the SQM-L lets you point outside the Milky Way for readings, since it has a narrow field of view. Maybe the app lets you pick a portion of the image for the measurement, or to exclude. Otherwise I think it would be of little value.


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dan777
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: derangedhermit]
      #5725391 - 03/11/13 08:55 AM

Quote:

Otherwise I think it would be of little value.



What if you can't see the milky way?


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Nop
Vendor (iPushto)


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Re: iPhone 'SQM' app available soon ... your thots? new [Re: dan777]
      #5727410 - 03/12/13 03:49 AM

FYI: We don't use the full frame in the app. The FOV is about 20degrees. We are still testing and adjusting.
We could substract the milky way influence by a formula. If the skies apppear to be dark, and the brightest parts of the milky way are in the Zenit, and the device is pointed at the Zenit. a correction value can be applied. But that can be tricky..


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core
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Madratter]
      #5727792 - 03/12/13 10:17 AM

Quote:

I think there is some confusion going on here between accuracy, precision, and objectivity.




Succinct and to the point, thanks for clearing it up!

Dan, I'd suppose if you can't see the Milky Way (assuming it's there and skies are clear) - that would probably mean the local LP levels are above the glow of the MW - in that case the SQM reading will be reading that glow signal which is above that of the MW's.

Norbert, thanks for the update on the app's FOV spec - a concern might be a confusion when users are reporting back SQM readings (especially to IDA) - the current SQM and SQM-L have fixed FOV and calibrated/temp compensated readings. Also, having the app take into account any Milky Way glow reading would skew the results, considering 1) the SQM meter does not do that 2) MW glow is not consistent across FOV.


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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Nop]
      #5728762 - 03/12/13 06:36 PM

Last night's numbers were above my SQM readings for the first time. Usually the app's numbers were lower. If we can find the happy medium, we are in business.

JohnD


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dan777
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Re: iPhone 'SQM' app available soon ... your thots? new [Re: johnpd]
      #5728846 - 03/12/13 07:21 PM

Quote:

Last night's numbers were above my SQM readings for the first time. Usually the app's numbers were lower. If we can find the happy medium, we are in business.



But was each device measuring the same FOV (not just total area, but same length and same width)?


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Re: iPhone 'SQM' app available soon ... your thots? new [Re: dan777]
      #5729727 - 03/13/13 06:04 AM Attachment (18 downloads)

@JohnD
I've updated the 5's algorithm.
FYI
We have provided a little 'tweaking' setting in the iPhones settings menu (look for dark sky meter). That can compensate structural differences between camera's. It's a kind of calibration. Say, the structural difference between your sqm and the dark sky meter is 0.1, just set the value (positive or negative) in the settings field.

Edited by Nop (03/13/13 06:26 AM)


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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Nop]
      #5730899 - 03/13/13 06:50 PM

Nice job Norbert. I will test the latest version (#38) tonight and see if I can come up with a good offset if needed.

JohnD


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Re: iPhone 'SQM' app available soon ... your thots? new [Re: johnpd]
      #5761793 - 03/28/13 06:47 AM Attachment (17 downloads)

A little heads up. This is a screenshot of the free Public Outreach 'lite' version aimed at a broad audience with the goal to provide tons of measurements worldwide.. It uses an approximate scale, no output in SQM/NELM and lacks the maps and weather features of the pro version. But this version will submit detailed measurements to researchers and the folks at the IDA.

Edited by Nop (03/28/13 06:47 AM)


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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Nop]
      #5763612 - 03/29/13 04:00 AM

Hi Norbert,

You say that the Lite version does not give a SQM value? I know the last one I tried just gave a poor/good/etc value. I am thinking of its value for submitting readings to the Globe at Night site. School kids could use the Lite version for that if a SQM value was available or there was some way of sending that value to the site.

JohnD


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Re: iPhone 'SQM' app available soon ... your thots? new [Re: johnpd]
      #5763614 - 03/29/13 04:05 AM

Hi John,
The SQM / NELM user feedback is in the Pro version. But in the lite version it's under the hood. The lite version submits these values as hi precision SQM values, along with position, pointing etc. The only difference is that these values dont show up in the user interface. These values can and will be used by the IDA and other parties. For instance Globe at Night. The added value is in the data. Therefore the app should be as simple as possible, attractive, free for the masses. Like we did with the VenusTransit app. More than 130.000 downloads in 2 weeks generating lots of useful data and raising awareness worldwide.

A sample of the data submitted:

datetime latitude longitude moonperc device deviceangle devicesqm
28-03-13 50,8 5,8 99 iPhone5,2 89 20,82

You can see that even the moon percentage is calculated, and if the device is correctly pointed towards the Zenit.

Edited by Nop (03/29/13 04:14 AM)


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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Madratter]
      #5763749 - 03/29/13 07:25 AM

Quote:


"Scientific objectivity means that independent observers, using the same procedures, will come to consensus regarding the phenomenon they are studying. In other words, personal opinions, values, and biases will not change observations recorded with scientific objectivity."




How about the biases in the procedures themselves? Any errors in the procedures, systematic or otherwise will be propagated. That would seem to be the problem here. It would seem that understanding a phenomena requires the use of multiple procedures/techniques that then converge on an understanding/consensus.

Myself, I would want an app that is reasonably accurate...

Jon


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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Nop]
      #5765710 - 03/29/13 08:44 PM

Hi Norbert,

Where would this data be submitted to so that a person could get at it and then use it to fill out the Globe at Night Reporting page?

JohnD


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Re: iPhone 'SQM' app available soon ... your thots? new [Re: johnpd]
      #5765920 - 03/29/13 11:19 PM

Hello Norbert, any news on the release date?

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Re: iPhone 'SQM' app available soon ... your thots? new [Re: crazyqban]
      #5768003 - 03/31/13 01:31 AM

I suppose it's a kind of catch-22. For the 'free' version, the user doesn't get any SQM or NELM numbers displayed; however this SQM reading is transmitted to IDA (with user's permission). The user only gets a descriptive "The sky is X time brighter ..." You can't check or calibrate the SQM app to an actual SQM device with the free version - for that you will need the paid version, which will then allow you to see the actual numerical SQM acquired. If there is enough device-to-device variation, I can foresee some issues with regards to the quality of data submitted to IDA via the 'free' version, especially since one would expect that there would be a lot more of those running compared to the paid version. In that case, perhaps another piece of data that should be submitted by the app to IDA is the calibration offset, and paid/unpaid status.

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Re: iPhone 'SQM' app available soon ... your thots? new [Re: core]
      #5768072 - 03/31/13 04:29 AM

The release is medio/end april. Depending on Apple. @core i couldn't say it better! There is an indicator (free/pro) in the database. And since it will be a mass product, i expect that measurements will not be at 'pro' level. But we hope to get a *lot* of measurements reducing possible errors. As we did with the VenusTransit app (15.000 good measurements out of 50.000, stil a lot!) But i'll leave the interpretation and reduction to researchers. @John, the data will be available on a website similar like this one: sqm.waarnemen.com . So it will be possible to lookup your own measurements and submit them to other sites/organisations.

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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Nop]
      #5808454 - 04/19/13 10:46 AM

The Dark Sky Meter app is now available in the App Store. Maybe I'll get a chance to try it out tonight.
...Keith


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Re: iPhone 'SQM' app available soon ... your thots? new [Re: microstar]
      #5809072 - 04/19/13 05:02 PM

I think I may have made a mistake , I downloaded this one , I think it requires an SQM-LE ( whatever that is) it cost me 6.99 ,
Is there a link to the proper one as this is the only one I can find.
[image]http://[/image]


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Re: iPhone 'SQM' app available soon ... your thots? new [Re: nevy]
      #5809085 - 04/19/13 05:06 PM

oops , I found it but its not available in the UK App Store , bollox , I've gone and wasted 7 lol.

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Re: iPhone 'SQM' app available soon ... your thots? new [Re: nevy]
      #5810542 - 04/20/13 10:32 AM

Downloaded. 5 bucks is a bit pricey for something that requires additional hardware to calibrate.

You ever think of making the 'lite' version pay and donate it to the dark sky association? That would be darn cool.


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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Raginar]
      #5816671 - 04/23/13 12:42 AM

I can borrow a SQM from our Planetarium so I hope to calibrate my iPhone 5 soon. I think $5 is a great price. I love that there are so many good Astro apps available for the price of a fast food lunch.

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Re: iPhone 'SQM' app available soon ... your thots? new [Re: JMW]
      #5816965 - 04/23/13 08:14 AM

I just downloaded the free version for evaluation purposes. Can I propose a product enhancement request for the Pro-version: next to the cloud prediction, why not incorporate seeing and transparancy forecast info. I would like to refer to "Sky Harbinger" in the App store in order to illustrate what I mean. This app gets its info from the 7timer website.

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Re: iPhone 'SQM' app available soon ... your thots? new [Re: Nop]
      #5843875 - 05/06/13 03:58 PM

Quote:

A little heads up. This is a screenshot of the free Public Outreach 'lite' version aimed at a broad audience with the goal to provide tons of measurements worldwide.. It uses an approximate scale, no output in SQM/NELM and lacks the maps and weather features of the pro version. But this version will submit detailed measurements to researchers and the folks at the IDA.




Hi, I can't download the app from the UK AppStore. Is there some issue with UK distribution?


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