trouble shooting help, please.

[forestgnome]

This is a Perseid meteor flashing through Big Dipper. The streak looks like that of a plane's blinking lights, but it's a meteor. Why is the streak broken into pieces? Could it be that my 80x CF card is too slow? Thanks for any help.

 

[forestgnome]

Hmmm... Now that I view this thread, the image is less broken. Is it because the image is displaying only a fraction of the original pixels? When I view this from "My pictures" on my computer, the streak is even more choppy. This image is only 16kb.

 

[kmorgan]

This is a Perseid meteor flashing through Big Dipper. The streak looks like that of a plane's blinking lights, but it's a meteor. Why is the streak broken into pieces? Could it be that my 80x CF card is too slow? Thanks for any help.

I'd have to see the original image in full size, but you have to consider that most of the meteors you see are particles the size of a grain of sand. I would imagine they are flaring up and down in brightness as they burn up and material ablates from the surface.

Kevin

 

[David Metsky]

It has nothing to do with your memory card, it can't affect an image like that. Looks like a normal meteor image to me, and a good one at that.

 

[MichaelJ]

I believe you're seeing a dichotomy in how this picture is displayed in different software due to its dpi setting.

If you view it pixel for pixel, it looks fine. This is probably how it appears in your web browser having been posted here.

If you view it in Photoshop or other editing software at "original size" it looks choppy because the jpg file has a 100dpi (dots per inch) resolution setting, so when this 700x440 image is displayed on a monitor (which almost always are 72 or 75dpi), it gets shown with proportionally smaller dimensions to try to appear its true size in inches, and being shown smaller causes the artifacts you're describing.

 

[DougPaul]

CF card speed will not affect the image. (It only affects the rate at which you can take pictures).

I agree with Dave--it looks like a normal meteor image to me. It would be best to see the original image--resampling (to change the size) can introduce artifacts.

Doug

 

[forestgnome]

Thanks for all responses. I beleive it is indeed not the cf card speed, but the way the pixels show on my screen. I zoomed in on my camera display and it looked right, so I loaded a larger file of the image. There are some hot pixels to clean up, but there's no problem with the meteor flash. Click "full screen" for a better view.

 

[David Metsky]

The ONLY thing that card speed can affect is how many shots you can take in a row in burst mode without delay, and whether you can keep shooting video in the fastest modes. It can't have any impact on the images in any way.

 

[JohnL]

Since we are talking about celestial objects, Mars will be closer to earth than at any other time in thousands of years on Aug 27 5:51ET. See here. We should see how this will photograph.

JohnL

 

[Tom Rankin]

http://www.space.com/scienceastronomy/mars_history_030826.html

JohnL

Check the date of the link!

 

[JohnL]

Ooops, I should have been wearing my reading glasses.

JohnL

 

[4000'er]

Since we are talking about celestial objects, Mars will be closer to earth than at any other time in thousands of years on Aug 27 5:51ET. See here. We should see how this will photograph.

JohnL

The Mars Hoax does surface each year about this time.

Two sites I like:
for general astronomy info is:
http://spaceweather.com/

Specific info like when the ISS will be overhead. can be found at:
http://www.heavens-above.com/

 

[ajtiv]

Dreamy Lunar eclipse Aug 28
Lunar eclipse

 

[darren]

Specific info like when the ISS will be overhead. can be found at:
http://www.heavens-above.com/

Very cool. I just used that site and the ISS won't be overhead here for a while, so I used the chart to find Jupiter:

Looks like you can see 3 of the moons. Ihave no idea, but thats what it looks like. It would be really cool if they were moons. I blew the exposure on Jupiter, but if I had a shorter shutter speed I think the moons wouldn't have shown up. So cool mistake I guess. It has now clouded over so I cant take any more.

I also used that site and managed to find the moon:

ha ha

- darren

ps: both shot at 400mm, so with the 1.6x crop they are 640mm equiv.

 

[darren]

Just found this site and it looks like those are 3 moons:

http://www.helmnet.com/astronomy/images/Jupiter/index.htm

Very cool.

Like I had guessed, the moons disappear when you expose for jupiter. Good thing I messed up.

Anyone have a 600mm and a 2.0x tc I could borrow?

- darren

 

[4000'er]

Looks like you can see 3 of the moons. I have no idea, but thats what it looks like. It would be really cool if they were moons.

They are called The Galilean moons: Ganymede, Callisto, Io and Europa. These are the ones Galileo Galilei discovered with his newly built telescope on January 7, 1610.

What is cool is that you can see their position change throughout the night, days and weeks.


More info

 

[darren]

Yah, I did some quick research and that is what I found. I remember now learning that stuff in grade school. I had no idea I could see those moons with my camera though. That is crazy.

This page is very cool. You can see Galileo's original observation sketches put into animation and then overlayed with telescope images. Click on the panoramic movie:

http://strangepaths.com/observation-of-jupiter-moons-march-1613/2007/04/22/en/

- darren

 

[darren]

Yup, the laws of physics still work. The moons do move. This is from tonight:

Very cool.

- darren

 

[forestgnome]

Darren, very cool work. Those moons can be seen in binoculars. Since you are viewing Jupiter lately, and since this thread has also mentioned the now perennial "Mars hoax"...

Jupiter is now in Scorpios, very close (from our viewpoint) to where Mars was a few years back, when it was at a point as close to Earth as it can get. This happens once in 17,000 years (or something like that). Earth passes Mars every 2 1/2 years, but each pass is at a different distance, due to our non-circular orbits.

Here is a shot from the summer(2002?) when Mars was at it's brightest as any of us will ever see. Hope you didn't miss it because it was stunning. It was technically just dimmer than Venus at her brightest, but the disk size was HUGE!!!. here, Mars floats above Scorpios over Mt. Passaconaway. This image is recommended with cognac, Enya and incense...

If you know the stars, you can see Antares, the heart of the scorpion, to the right of Mars. Antares is one of the brightest and largest stars we can see. Mars is usually nowhere near this big. It was wonderful to have another huge wanderer that rivals Venus and Jupiter.


happy Trails