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ISS, Saturn, APOD, 1-22-2016

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#51 KevinS

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Posted 25 January 2016 - 09:27 AM

I took this incredible picture yesterday  :lol:

 

 

 

Darn! If you were only 40 meters further North. Better luck next time.



#52 Fil

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Posted 25 January 2016 - 10:18 AM

I find it strange that each frame of the ISS can be placed exactly on top of the others, and they match pixel per pixel!

The "placing" (now I use this word) of each ISS frame is not evenly spaced, too...

If we estimate a speed of 360 degrees in 95 minutes (same as 277.4 arc-seconds per second), the frame rate would be around 6.78 fps, with some variations from 0,6 to 25 milliseconds.. video cameras are usually pretty good at keeping a stable time to within a few milliseconds, so this is unexpected for a frame rate lower than, say, 500fps .. The ISS closest to the planet also seem to be closer to each other than the other ones..

 

On the 15th of January, Saturn was 42 degrees away from the Sun, so we know how the ISS was being lit "from behind". We just need to know how it is usually oriented, to see if it matches its white areas we see...

 

Does anyone know if the ISS keeps the solar panels aligned vertical to orbital plane of the Earth around the Sun (vertical to the ecliptic)?

 

But for a planet/ISS less than 20 degrees above the horizon, they have really nice amount of detail!


Edited by Fil, 25 January 2016 - 10:27 AM.


#53 wargrafix

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Posted 25 January 2016 - 10:57 AM

I took this incredible picture yesterday  :lol:

 

ncc%201701.jpg

 

****...how did you see my ship? Thats the one I use to take my planetary and lunar shots!



#54 t_image

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Posted 25 January 2016 - 11:28 AM

I find it strange that each frame of the ISS can be placed exactly on top of the others, and they match pixel per pixel!

Sure you might expect to see variations based on noise or atmospheric distort...

but if you are expecting to see differences like in ISS rotation as you see in videos with the mount tracking the ISS,

remember the shot is less than 1 second across a small field of view.

Even though the ISS mount tracked videos are also a small field of view, the mount is tracking across a large path of sky-maybe the entire pass from maybe horizon to horizon.....

Alessandro's posted link video covers 10 seconds.

 

The "placing" (now I use this word) of each ISS frame is not evenly spaced, too...

This is a fair observation.

It is true as a satellite travels across the sky it's apparent rate of travel from the observer's perspective will vary-it will look to be moving quickly at the horizon and slower as it crosses directly overhead.

So you would see variance in frame spacing only over a long video with a large FOV [moot as you couldn't resolve the ISS unless it was a very high res photo] but the trend would have a predictable variance.

You should see a consistent spacing if the mount that is tracking Saturn doesn't do anything fancy during the short episode.

If we estimate a speed of 360 degrees in 95 minutes (same as 277.4 arc-seconds per second), the frame rate would be around 6.78 fps, with some variations from 0,6 to 25 milliseconds.. video cameras are usually pretty good at keeping a stable time to within a few milliseconds, so this is unexpected for a frame rate lower than, say, 500fps .. The ISS closest to the planet also seem to be closer to each other than the other ones..

If you mean you should see a difference in size of the ISS within the less than 1 second set of frames because there is a point where it is closer, interesting, but I don't think without a super-high resolution imaging of the ISS (like with the Canon 100megapixel camera or something) you would see the variance in such a short time period.

 

On the 15th of January, Saturn was 42 degrees away from the Sun, so we know how the ISS was being lit "from behind". We just need to know how it is usually oriented, to see if it matches its white areas we see...

?Don't understand how this tells you how the ISS was being lit. Go to Calsky.com and enter the place and date of the ISS occultation of Saturn for the given photo in question and the site should accurately give you the distance from observer, it's apparent rate of travel at the point in the pass, the apparent magnitude at the time,etc.etc.

Does anyone know if the ISS keeps the solar panels aligned vertical to orbital plane of the Earth around the Sun (vertical to the ecliptic)?

This will inform your question:

http://www.heavens-a...ed&alt=0&tz=UCT

The panels do move to track the Sun.

But for a planet/ISS less than 20 degrees above the horizon, they have really nice amount of detail!

I'm not familiar with the quality of the scope. Obviously atmospheric distortion get more problematic.


Edited by t_image, 25 January 2016 - 11:34 AM.


#55 t_image

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Posted 25 January 2016 - 11:51 AM

I'm not concerned with defending a photo that has been taken down, hinting that is was pretty sketchy....

 

 

I'm only concerned with bad science theories.

Please tell me people, you realize that given certain passes of the ISS,

that the brightness in magnitude of the ISS photographed will vary depending on numerous things...

If it is at it's orbital perigee and 100% illuminated it can be some -5 mag,

but it also can be photographed during some instances where it is exactly the same magnitude as Saturn.....

You can also photograph it going from being lit to being in the shadow:(As Jerry L shot:)

http://www.cloudynig...hl=+iss +shadow



#56 t_image

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Posted 25 January 2016 - 12:04 PM

I took this incredible picture yesterday  :lol:

 

ncc%201701.jpg

Sorry Fronk.

It only counts if you had taken a selfie with it while holding a copy of a legitimate newspaper with today's date.



#57 aaube

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Posted 25 January 2016 - 12:40 PM

I'm not concerned with defending a photo that has been taken down, hinting that is was pretty sketchy....

 

 

I'm only concerned with bad science theories.

Please tell me people, you realize that given certain passes of the ISS,

that the brightness in magnitude of the ISS photographed will vary depending on numerous things...

 

 Yes, it's quite obvious now.  We certainly all need an education.

Thanks for providing it.

 

Alain



#58 Fil

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Posted 25 January 2016 - 01:23 PM

Thank you for the link on the real-time "behavior" of the ISS! It seems as if the main structure holding the panels is roughly pointing North-South... So it roughly matches how we see it in the image (perpendicular to Saturn rings) so I cannot argue anything there.
 
1 second across (time) means roughly 25 fps, or "video-speed" equivalent!... This goes against my observation of nearly 7fps!
I compared "1 Saturn diameter" (15.6 arc-seconds), assuming this referred to the planet equatorial diameter excluding rings, and ignoring any 10% asphericity from a spinning ball of gas!! I made my speed estimate geocentrically. That is not where the observer was! So, redoing this for 1000km away from the ISS (distance to where someone at 54ºN 27ºE would see the ISS, around 7:00:00, at its highest, and thus moving nearly perpendicular to the observer), moving linearly" at 7.6 km/s of the ISS would imply moving 5 Saturn diameters in 1/20 of a second. So my new estimate for the approximate frame rate is 40 fps.
This is closer (than my previous calculations) to a plausible non-fakeness of the photo.
The time differences that would justify the non-even placing of ISS frames are now between 0.09 and 3.70 milliseconds, which "might" be expected from a video camera...
 
I still do not like the pixel-per-pixel comparison of every ISS frame, as I would expect: seeing to change it, and I would also not expect the the video camera would sample the ISS falling squarely an integer number of pixels to the side! I would expect one ISS image to be half a pixel to the side, or 0.3 pixels to the side... But not precisely aligned with pixels, all these 20 consecutive times.
 
Maybe the author observed the transit, and processed the ISS and the planet to look the best and combined the images in the places where they were, so he had best quality-looking image. It's like taking a picture of the ISS and "photophopping" it into the same picture of Saturn.
 
Another aspect I notice, is the sun should be shining on Saturn from an "East-Southeast" direction, or some give-or-take 10 degrees CCW of the long-axis of the ellipse we see the rings in.
Looking at the ISS, the panels seam to point "upwards" in the image, and not facing the Sun! Maybe they were pointing like that so they do not provide too much electricity (?) But the shading on the ISS also seems to suggest it is being illuminated from "above" in the image.
 
If I flip my interpretation East-West, the illumination 10 degrees CCW of the flipped image, becomes perpendicular to the panels...

 

kGyvz0S.png


Edited by Fil, 25 January 2016 - 01:35 PM.


#59 Alan French

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Posted 25 January 2016 - 01:35 PM

The January 22 APOD has been retracted and replaced.

 

The folks at APOD provide a valuable service, and I very much enjoy a visit every morning. They can't possibly be the "image police," so I can't fault them for the original posting. It might have taken longer than it should, but the APOD was deleted.

 

Please return to your imaging so we can see more fine, credible photos in the future.

 

Clear skies, Alan



#60 HxPI

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Posted 25 January 2016 - 06:27 PM

So would this have been an acceptable APOD if it wasn't presented in false pretenses or are they looking for something more "genuine"? Just curious....

 

Glad to see this has been resolved!

 

Ciao,

Mel



#61 t_image

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Posted 25 January 2016 - 10:40 PM

Would be interesting if APOD style contest/postings also posted the rawlike data of the capture.

(like here is one sub unprocessed:...)

Would be nice to be able to separate a little of the science of the capture from the art that comes a lot from processing.

But in a world where every magazine cover is airbrushed, what are we to do?

Props to everyone that did play CSI to out a fake!



#62 robin_astro

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Posted 26 January 2016 - 07:06 AM

In the real science world of peer review the author has to provide enough details to allow the result to be reproduced otherwise "it didn't happen"  In this case the raw frame showing the transit with the capture details was the key evidence and the APOD team would have been wise to at least have asked to see it before publication of the "pretty picture" version.

 

For me a negative result (eg the ISS  just missing Saturn) would have been potentially far more interesting as it tells us that  for some reason the calculated track was in error.

 

Robin


Edited by robin_astro, 26 January 2016 - 07:33 AM.


#63 bunyon

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Posted 26 January 2016 - 08:49 AM

The January 22 APOD has been retracted and replaced.

 

The folks at APOD provide a valuable service, and I very much enjoy a visit every morning. They can't possibly be the "image police," so I can't fault them for the original posting. It might have taken longer than it should, but the APOD was deleted.

 

Please return to your imaging so we can see more fine, credible photos in the future.

 

Clear skies, Alan

 

I just wanted to applaud this statement.  I've been following this on multiple threads over several days of travel and I know that my imaging abilities and knowledge lag far behind many who were "on the case".  I believe the imager deserves all of the criticism he's gotten, perhaps more.  However, the guys running APOD aren't doing it as their main job (I doubt they're even paid).  If you like APOD, that's great, but it isn't "peer-reviewed science".  It's a pretty picture contest that can bring some attention to cool science and drive imagination.  Expecting the guys who make the selections to be as aggressive with their evaluations as you suggest seems well off the mark.  They have other jobs that require their attention and for which they're paid.  In the end, they looked at the criticism, asked some questions and withdrew the picture.  "BUT IT TOOK DAYS!!!!" Well, geez, just because it's on the internet doesn't mean it will move at the modern speed of instantaneous.  Days is pretty fast for a retraction.

 

If the imaging community expects more from APOD, my advice to the fellow academics who are running the site would be to shut it down or at least find some sucker to take it over.  There is no way I would devote the time needed to vett every image that comes my way as carefully as I would review a manuscript for publication.  I also would not expect NASA to devote the kind of energy that would require.  They should be trying to go to space.  APOD is fun but it shouldn't prevent anyone in the agency or associated with the agency from doing "real" work. Maybe that's just me but I've never thought of APOD as "science".  No offense to those of you who have had images selected. 

 

On the other hand, it's a nice reminder, I think, to everyone submitting images that they should stand prepared to deliver details of processing and raw images, including video.  Certainly if you expect the image to be used for science - that is actual data collection - the raw data is very important. More than very important, it is essentially the only important thing.

 

Also, thanks to the many of you who took the time to go through the image and describe/discuss what you found.  It should be a helpful guide to what goes into planetary imaging and what level of detail needs to be provided when "publishing" and image (I use quotes because simply uploading to a public forum isn't reviewed publishing either).  I certainly learned a lot as I followed this thread and the ones on facebook. 


Edited by bunyon, 26 January 2016 - 08:51 AM.


#64 ToxMan

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Posted 26 January 2016 - 12:26 PM

Just imagine the guys at APOD looking over submissions, and catching this one and saying among themselves, "Oh hey, look! Someone finally got a nice shot of..." without ever thinking someone would misrepresent what they were actually able to accomplish with the digital data they collected. Thirty years ago, astrophotographers could only dream of producing a fraction of what is possible now. So, down the road, this will be forgotten.



#65 bunyon

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Posted 26 January 2016 - 12:43 PM

I'm not sure if others have seen it, or if I should post it here, but there is, incredibly, another ISS transit of Saturn video that has appeared (it was linked in Phil Plait's Slate column and the link is below). 

 

https://www.youtube....h?v=tB76_hubraI

 

That one looks pretty good to me and just as incredible as the first. 

 

I must not be using CalSky right - I never can get it to be that accurate (well, not THAT accurate, I've never tried a planet transit.  But I've missed on a couple of solar transits).  Ah, well.



#66 wargrafix

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Posted 26 January 2016 - 01:35 PM

I am going to try for saturday's transit. But its going to be hard. Why? Aside from the inherent difficulty of an ISS transit shot, ISS transit can change. Where I thought it would be yesterday changes because the orbit alters. Its moved south of my planned spot. I be tomorrow it will change again.



#67 HxPI

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Posted 26 January 2016 - 02:09 PM

The ISS Transit Prediction tool is great!



#68 wargrafix

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Posted 26 January 2016 - 02:33 PM

I use it, but you have to refresh the data since the orbit refines and moves off the first path.



#69 t_image

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Posted 26 January 2016 - 04:58 PM

Good luck in your attempt Wargrafix!
Do wait until after January 27 for the orbit maneuver rocket burn and then for them to correct the TLE's.

Some tricks that have helped me:
get 2nd and 3rd opinions.
Check the TLE's that your prediction programs are using.
Calsky, Heavens-above and n2yo all will describe what TLE's they are using.

Nasa publishes and spacetrak,etc.
http://spaceflight.n...ISS/SVPOST.html

The good news is the ISS is so tracked that there are lot of resources to consult to verify what is trustworthy.

If you find everyone agrees and is using the same TLE's---that's a real good sign.
I have seen them using TLE's that were different because the Epoch date (how recent) was different as well. Sometimes this happens.

 

What I've done that has given me success 3 times:

  • I consult calsky to see if there is a close pass (can change maximum distance to centerline and move date period out for weeks).
  • When I scroll down the ISS events I find a "close to Sun/Moon" situation.
  • I look down at the centerline, closest point >map readout....where the distance= is given.  I decide if it is worth driving to (calculates given the closest point tangent to the centerline pass).
  • I look above to the second line of the event report where it says Angular diameter=    .I then decide (anything over 25 degrees is nice, over 38 is great, 50" is amazing, ect)  if it will give me a chance to resolve it better since the higher the pass, the closer it is to the camera, plus the more square it is oriented towards the camera, the larger it will appear.
  • If it is a night pass I look to see if it is lit (will give a magnitude prediction number), or will say it is in the Earth's shadow--(better to see a silhouette against the moon).
  • I then click on "centerline".....[I have found clicking on closest point useless and confusing since it automatically decides where along the centerline you want to be (for the closest/largest shot) but may not be a location you can set up from---so I like to see the whole centerline pass map]

 

  • I then look real quick at the "age elements" that will give you a clue of Calsky's confidence based on how old the TLE's are. [The best chance is to plan ahead and consult Calsky close to the event as well to see if the TLE's are fresher and will give you more accurate calc's.]
  • Look over to the left at what the time/date setting is and what duration and time interval is defaulted to (will usually advances to the selected event date/time and gives a 10 seconds duration with .2 second interval.
  • Calsky gives you a nice google map with a plot with the red boxes (for Sun)  pointed for every interval and the line extends for the 10 second interval.....
  • If you change the duration setting it will extend the centerline....
  • I then figure where I could drive and set up as close to the plotted centerline as possible. I zoom in, look at the location-maybe a park I can set up at, etc.
  • The report gives width= to indicate how fat or wide the centerline is so that if you are within the track you may see it either at the limb or dead center if you are at any point on the line itself.
  • Then I click back (might have to start search again)....and get back to the event report list [make sure the event time/date settings are what you want]---sometimes if I click back twice to get back to the event report it is stuck on the pass time/date [which is fine for my purpose].
  • I look down to the Centerline,closest point >map ......and I click on "map"
  • Calsky will give you a google map with a house icon randomly placed along the centerline.
  • I zoom out, and drag the house icon to the location chosen from the last map that is dead on the centerline at some point (from your last map recon).
  • [Consider visual obstructions (trees/buildings,etc) and at what point above the horizon you will see it.]
  • Once happy with my location I click "click here" to use this place as observer site.
  • It will then take me to the homepage with a notification site coordinates have changed.....
  • I then start over click on  satellites>ISS...
  • The Event report then has the event with the detail "you are on the centerline of this transit!"
  • Note also a report of the time uncertainty.....the less variability the better!
  • So the icon and ISS in the event report--ISS is clickable.
  • I then Click on the ISS and it will give me an image with the Sun (and any current sunspots as landmarks) and the ISS pass line across the Sun based on how close to the centerpass line of the transit you have chosen....
  • I printscreen the image so once on site I can note the Sunspot landmarks so I can orient where the ISS will go across.
  • I consult heavens-above and set my location the same lat/long as I ended up with on Calsky.
  • I select ISS *but I have to ask it to report all passes "Passes to include:"(since a solar transit will be during the day and h-a defaults that you don't want info on a pass that will not be visible)......
  • Then with the passes list I click on the one with the period of the time/day event from Calsky.
  • Notice h-a will tell you the pass from horizon to horizon.
  • I click on the dat and it will give me a star chart (although the one during the day will not show the stars....)
  • Notice the chart is meant for you to look at it as if you were holding it above your head and pointing North towards the North.
  • This is very useful because it will confirm Calsky (with crossing the Sun, what time it will cross, what part of it's path across the sky it will transit, and from what direction it will start and what direction it will disappear (note the arrow direction).....
  • I then add this information with the image of the ISS crossing the Sun with sunspot landmarks, I can know which side it will start across the Sun and which side it will travel towards..
  • I then set up, giving myself always a larger cushion of time than I think I need.
  • As the time ticks towards the event I have done my test records and focus and etalon adjustments......
  • I start recording maybe 1 or 2 minutes before and watch with my large display connected to my camera (usually my 40" 4K tv in my car)...
  • I also notice any current sunspots and where it will cross my view given my camera and scope orientation to the Sun compared with h-a skymap and Calsky map. Stellarium is also helpful for this....
  • Mostly I don't see it happen live(latest solar transit I did see it!) ...
  • So I let it record a minute or so past the event time just in case.....
  • Afterward I consult my recording and see it go by (notice the duration is usually quick 1 second or less)--so don't expect to fast-foward and see it>it may take several times watching to see it!!!!!
  • My setup only allows me to record 30fps for 4K resolution so I settle with the blur for now...

Cheers!


Edited by t_image, 26 January 2016 - 05:01 PM.


#70 stephenramsden

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Posted 28 January 2016 - 10:35 AM

"Both of us are retired and beholden to NO ONE"

That was my favorite post out of any of this...:)  

go get'em Dan!  


(disclaimer-Rich Jakiel, Dan Llewelyn and Alan Coffelt brought this to the attention of the astro-nerd world.  I simply added my piece in and blew it up on social media)  


 



#71 gfeulner

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Posted 28 January 2016 - 11:24 AM

http://earthsky.org/...12729-394610165



#72 wargrafix

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Posted 28 January 2016 - 02:43 PM

As I suspected, the orbit is pushing it further south. Still in driving distance, but at that time of the morning? Not a chance.



#73 metrolinaszabi

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Posted 30 January 2016 - 07:43 AM

Hi everyone,

 

I was following the topic on the famous photo of the ISS-Saturn transit here and there and I must say, I was so impressed by seeing how the astro-imaging society came together as one on this subject.

 

Please allow me a brief story.

I booked my holiday a few months ago to Gran Canaria to have a winter holiday at a nice warm location for the first time. I've been in astrophotography for 3 years now and take my hobby with me wherever I can. So I was planning to take my small travel scope (Skywatcher Skymax 90/1250 maksutov) with me to do some astronomy there under that wonderful clear night sky. The scope fits into a hand luggage, that I could take with me aboard the plane and the eq1 mount was checked in into a big suitcase. My main targets were ISS close up, Tiangong, HST and OTV-4 (last three for the first time), but none of these I could manage to capture due all kinds of problems.

Before I actually travelled, double checked the app called ISS Transit Prediction just to see what if.. than realized ISS might transit the ringed planet on the 25th of Jan... But I was very sceptical (coming from London it is an obvious reaction) as always, you never know the weather and other circumstances that can ruin the careful planning....

 

But everything went fine, sky was exceptionally clear and everything was ready for a good attempt...

I mainly worked with dslr  so far and only recently bought myself an ASI 120 MC planetary camera, I had lots of doubts about my own skills, mainly about camera settings (choosing the right gain and exposure), plus to fine control an eq1 mount with an ASI on it is, well let me say not the easiest thing to do..... but my equipment was given, couldn't change it so had to deal with what I've got, still much much more that having a dslr only :)

But here is the final result, a nice video about the best astro-moment of my life. It was uplifting, rewarding and a fantastic feeling to see it actually flying through the queen of planets :)
I gave my very best to document the event as real and precise as possible.

 

I've seen here a discussion about frame rate. Well for some reason my ASI cam missed one frame after the actual transit, no idea why. I was recording at average of 40fps, normal USB 2 port so might be the data transfer or whatever technical reason... but at this fts it was absolutely feasible, no solid white line of ISS, instead individual frames and the four separate photovoltaic arrays are nicely there on most of the frames. Bit overexposed, but that's the only way this two objects can be caught in the same time, compromises on both sides.

 

So here is:

 

- a video with the original footage:
https://www.youtube....h?v=tB76_hubraI

- a time lapse video to show us, the four panets on the sky and ISS crossing Saturn as a small dot:
https://www.youtube....h?v=pGMAzWRUVWY

- a composite image of two layers, one for the ISS frames and one for Saturn, Mind that for the Saturn photo I only used the frames that were in the original, 22 sec footage, processed it in PIPP, AS2!, Registax and Photoshop. Than these two layers were merged according to their original position, no fakery involved, only enhancement of the existing data:
https://www.flickr.c...ublic/lightbox/

- and a widefield photo with a Canon 600D and a Samyang 8mm f3.5 fisheye lens of us, the surrounding area, the night sky, ISS trail and the four visible planets – only Mercury as missing due it's low position at the time, 4 degrees only... shame :)
https://www.flickr.c...ublic/lightbox/

 

- also a link from Erathsky.com:
http://earthsky.org/...llows-apod-fake

 

 - and another one from Phil Plait (Bad Astronomy) where he mentions my catch at the bottom of the article

http://www.slate.com...s_not_real.html

Now I'd like to ask your help. I've been browsing through the internet to find similar shots to mine, but I only found the ex-APOD one which does not count anymore. Are you aware of any other successful attempt on this subject? If yes would you please share it with me?  I've seen some photos of the ISS close to Saturn, but not actually covering it :)

 

Many thanks and clear skies!! :)
 

Szabolcs


Edited by metrolinaszabi, 30 January 2016 - 07:52 AM.


#74 WarmWeatherGuy

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Posted 30 January 2016 - 09:56 AM

After looking at those very cool pictures of the ISS transiting Saturn I am scratching my head about how webcams & FireCapture work. On FireCapture there is a setting for exposure time but no setting for FPS. It gives you a frame rate of 1/exposure time if possible otherwise it gives you the max frame rate. If you set the exposure time to 0.025 seconds then you get 1/0.025 = 40 FPS. My thinking is that the shutter is open for 25 milliseconds, then the integrated frame is copied to memory, and the next frame begins. I figured the time required to grab the frame was so small it was insignificant, perhaps a microsecond. This would result in a blurry streak for the ISS for each frame with almost no space between streaks. From looking at the video it appears that during the 25 milliseconds the shutter is only open perhaps 2.5 milliseconds and the other 90% of the time is spent copying the frame to memory.

 

I figured the original APOD faked image was made with two C14s. On stayed on Saturn and the other tracked the ISS. We can all see that Saturn had to have been stacked so I figured that was done with the scope that stayed on Saturn. I also figured the ISS image was stacked for a short time interval before and after the transit. Then that stacked image was photoshopped onto the stacked image of Saturn using the original video to inform where to place the ISS images.

 

Can someone confirm that when we set the exposure time to 25 milliseconds that we only get around 2.5 milliseconds of exposure in order to get the 40 FPS?



#75 HxPI

HxPI

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Posted 30 January 2016 - 10:43 AM

Why do you think the exposure should only be 2.5 ms? Does the image only "look" like a 2.5 ms exposure?? I'm not sure a 25ms exposure would cause a blurred image at the given focal lengths. However, 25 ms gives you 40fps already (1000ms / 40 = 25ms) so that seems to be the correct exposure. If that's not the case, then it seems pointless to have an exposure setting showing incorrect exposure times! Perhaps the keyword is "average" and in reality it can be more or less.

 

Thanks for the question.

 

Ciao,

Mel


Edited by HxPI, 30 January 2016 - 10:54 AM.



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