What a 600,000-megapixel-wide picture looks like • Hacker News Board

Re: What a 600,000-megapixel-wide picture looks like

#91

Post by treenyc » Mon, Aug 05, 2013, 1:27 AM UTC

nakedrobot2 wrote: post #67

Hi, I'm the photographer who made this image. Thank you for all the attention :-) Let me try to answer some of your questions, in no particular order: 1) Here is the original page: http://360gigapixels.com/tokyo-tower-panorama-photo/ also here is a youtube screen capture showing a few highlights, if you are feeling lazy ;) https://www.youtube.com/watch?v=NboCijiLwmI 2) it is not 600,000 megapixels. It is 600,000 pixe…

Hi nakedrobot2 , I was wondering if there is any way for us to use the technology that you used to make this photograph. Let me know how we can contact you.

Re: What a 600,000-megapixel-wide picture looks like

#92

Post by tripzilch » Mon, Aug 05, 2013, 2:55 PM UTC

nakedrobot2 wrote: post #67

Hi, I'm the photographer who made this image. Thank you for all the attention :-) Let me try to answer some of your questions, in no particular order: 1) Here is the original page: http://360gigapixels.com/tokyo-tower-panorama-photo/ also here is a youtube screen capture showing a few highlights, if you are feeling lazy ;) https://www.youtube.com/watch?v=NboCijiLwmI 2) it is not 600,000 megapixels. It is 600,000 pixe…

To anyone else having problems with the controls: using the keyboard works very well! (arrow keys + shift/ctrl to zoom in/out).

Re: What a 600,000-megapixel-wide picture looks like

#93

Post by maaku » Mon, Aug 05, 2013, 7:01 PM UTC

Someone wrote: post #90

maaku wrote: post #61

Earlier quoted context omitted.

Atmospheric effects. Atmospheric refraction adds significant noise, fully obscuring features smaller than about 0.25 m. Yes, ground telescopes have ways of cancelling out atmospheric effects, but the required calibration and long exposure is impossible with the orbit of spy satellites.

I don't think it takes long exposure. Ground-based telescopes can make the simplifying assumption that they are looking at static point sources. That makes it easier to correct for camera movement and for optical defects from the lense and the atmosphere. On the other hand, looking down is a bit easier than looking up because the atmosphere will converge rays looking down, but diverge them looking up. See http://what…

Adaptive optics is far too complex to summarize in a HN comment: http://en.wikipedia.org/wiki/Adaptive_optics

Hubble is of the best spy satellites. It was built by the same team that builds spy satellites, using all the same parts and equipment, tested in the same facilities, etc. It just has a slightly different secondary mirror setup and a very different set of instruments and control mechanisms, since it's meant to point at galaxies and do astronomy, not at the Earth doing surveillance.

Seriously, one of the hardest parts of the Hubble program was figuring out how to do it in the view of the public without revealing the underlying surveillance programme.