where's the stars?, page 1
Pages: <<  1    2    3  >>
ATS Members have flagged this thread 1 times


reply posted on 28-6-2009 @ 09:07 PM by peacejet
reply to post by korath



It depends on the exposure time of the images. For example, if you take a image with a camera with a shutter time of a second during night time, you will get a black image. But, if you release the shutter and expose it for say three minutes, you will get some stars, because more light reaches the camera.

It all depends on the exposure time.

An important principle of exposure is reciprocity. If one exposes the film or sensor for a longer period, a reciprocally smaller aperture is required to reduce the amount of light hitting the film to obtain the same exposure. For example, the photographer may prefer to make his sunny-16 shot at an aperture of f/5.6 (to obtain a shallow depth of field). As f/5.6 is 3 stops "faster" than f/16, with each stop meaning double the amount of light, a new shutter speed of (1/125)/(2·2·2) = 1/1000 is needed. Once the photographer has determined the exposure, aperture stops can be traded for halvings or doublings of speed, within limits. A demonstration of the effect of exposure in night photography. Longer shutter speeds mean increased exposure.


The true characteristic of most photographic emulsions is not actually linear, (see sensitometry) but it is close enough over the exposure range of about one second to 1/1000th of a second. Outside of this range, it becomes necessary to increase the exposure from the calculated value to account for this characteristic of the emulsion. This characteristic is known as reciprocity failure. The film manufacturer's data sheets should be consulted to arrive at the correction required as different emulsions have different characteristics. Digital camera image sensors can also be subject to a form of reciprocity failure.[10]


Take a look at this image. It speaks for itself.



Source-

Wikipedia


reply posted on 28-6-2009 @ 09:14 PM by weedwhacker
reply to post by korath



What was the f-stop and exposure?

Why would you take a picture of Earth in the dark? Usually, when photographs of bright planets are taken the stars won't show 'cuz of the short exposure time.

Oh, and ignore someone who says light needs air for it to travel through to be seen --- that's nonsense.




reply posted on 28-6-2009 @ 10:34 PM by peacejet
reply to post by musselwhite



You live in the city? If so, it is because of the light pollution which blocks all the star light and making only the brightest ever objects in the sky visible.

To see the stars, go to a very remote place, like a village or the top of a mountain where there are no lights to interefere with the stars and see the sky in all its glory.



reply posted on 28-6-2009 @ 10:40 PM by RuneSpider
reply to post by peacejet


One of the things i loved about living in the country was the star gazing.

Light pollution is one of the reason why you''ll also hear birds that are normally asleep at night being active.


reply posted on 28-6-2009 @ 11:27 PM by ahnggk
reply to post by korath



Go talk to someone expert in photography. He/she will tell you it's no conspiracy and will give a perfect explanation.

I do some astro-photography myself. I tell, it's very difficult to combine a good *usable* image of say, the moon, together with the stars. Say if you try to grab the stars with the moon. You have to use longer exposure times. The resulting image will make the moon appear like the sun, and of course, some stars in the background.

Do yourself a favor, get informed, and for best results, try to do it yourself You don't have to buy expensive DSLR cameras btw, just the simple digital point-and-shoot nowadays can have long exposure times, long enough to bring out the faint stars...


reply posted on 29-6-2009 @ 12:34 PM by Sentry-
Originally posted by ahnggk
Originally posted by Sentry-
I haven't read through the posts in the thread, so I am sure someone has already gave you this reason, but I will state it anyways..


It would've been better if you actually read the other posts before replying. Because IMO, you are basing your opinion on visual observations and you might just confuse the OP. Although I'm not saying you're completely wrong.

Others gave a much better answer based on photographic observations. It's a different thing. You don't actually see this 'washed out' effect on pictures except on 'over exposed' images which are normally discarded, and never makes it to publication.

[edit on 29-6-2009 by ahnggk]


I am sorry to upset you, but im not trying to confuse the OP, the OP is wise enough to take in the general reasoning by reading all the posts, and have an understanding. There are facts to this however, it has to do with the way the light reflects as well as the specifics in terms of the cameras they are using as well as the exposure settings and so on, but I am just giving the general point on why if you were on the moon you might not necessarily see every single star out there. When I say washed out I simply mean the stars are not as visible due to another source over powering that light. Again, sorry to upset you, but there are various factors in why the photos appear the way they are, and what I said is one of the reasons.

The point is there is not really any concpiracy to be played out here, it is a matter of science that has to do with various elements of light reflection, exposure, etc...


reply posted on 29-6-2009 @ 10:51 PM by pluckynoonez
reply to post by korath



Where is the stars? Where are the stars? I do not know. Up, maybe? You are going to help me.


reply posted on 30-6-2009 @ 04:58 AM by Exuberant1
Originally posted by pluckynoonez
reply to
post by korath



Where is the stars? Where are the stars? I do not know. Up, maybe?


Check this picture - No stars in this version...:

www.hq.nasa.gov...


This one looks 'unreal' - it also has a star which can only be seen in the higher resolution images...

www.hq.nasa.gov...

Here is the Higher Res version - Note the 'star' in the top left corner, which was absent from the lower resolution version:

www.hq.nasa.gov...


*Does anyone notice anything strange about the earth in this image?





reply posted on 30-6-2009 @ 08:46 AM by Soylent Green Is People
reply to post by Exuberant1


That may be a star (or planet). Perhaps it's so small on the original photograph that it only shows up as one pixel in the higher-resolution scan, and therefore disappears at lower resolutions (i.e., it's much smaller than one pixel in the lower-resolution.)

Or perhaps it's a "spot" on the original negative itself (and was not really there when the picture was taken) that is only big enough to be resolved as one pixel in the higher-resolution scan. It could also be one-pixel error in the "jpg" file.


....and I give up -- what's strange about the Earth in that photo?



[edit on 6/30/2009 by Soylent Green Is People]


reply posted on 30-6-2009 @ 08:51 AM by weedwhacker
reply to post by Exuberant1



Yeah...what Soylent asked...what do you see that others can't??

(I really can't believe this 'no stars' baloney is still going...and going...and going....)

[edit on 6/30/0909 by weedwhacker]
Pages: <<  1    2    3  >>    ^^TOP^^



"My God, its full of stars!"
  Posted 19 days ago with 83 member flags
Newfound "super-Earth"
  Posted 8 days ago with 56 member flags
Enceladus Backlit by Saturn
  Posted 2 days ago with 50 member flags
Toronto teens send Lego man into space: video
  Posted 16 days ago with 28 member flags
Amazing new photo of Earth. The Blue Marble 2012
  Posted 12 days ago with 22 member flags
NASA Probe Captures 1st Video of Moon\'s Far Side
  Posted 9 days ago with 19 member flags