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View Full Version : I've lost the BA's description of "Bad Photos"



JackC
2003-May-27, 06:59 PM
Greetings all.

I've recently received a photo (http://www.cyberspaceorbit.com/0001919.GIF) (SOHO apparently) from a friend of a friend. The item is from CyberSpaceOrbit, which immediately puts it in woowoo territory, but in trying to comment back to my friend about the image, I tried to find descriptions of what happens in digital photos - and can't seem to today.

I also can't seem to find any reference to it here already - if there is reference here, a link (or reference) would be great.

The pixle flare bit to the left is easy to understand and explain - but I am not sure about the linear bit.

So - two questions - where is the BA's description of photo interpretation (or am I loosing it and thinking about a link to another site?) and two: what shall I give my friend as an explanation for the straight line in this image?

Thanks much.

Jack

Comixx
2003-May-27, 07:16 PM
I think the page you're looking for is here (http://www.badastronomy.com/bad/misc/planetx/soho.html). I had to go looking for it yesterday (before the bandwidth outtage :/) to reply to one of bmpbmp's posts.

Hope that helps.

JackC
2003-May-27, 08:19 PM
Comixx

Thanks! That is indeed the area I was looking for. Have to attribute not finding it to being a little pressed for time today.

I am thinking the closest explanation for the straight line trace at the left of the sun off the pixel flare may be either a comet or maybe a particle in field. I didn't see any direct reverence to these sorts of traces - though the palm fronds were nice and pretty!

Lately, I have not had enough time to read closely enough on this stuff!

Thanks again!

Jack

Comixx
2003-May-27, 08:46 PM
Pertaining to that linear streak near the pixel flare: Its really hard to tell what that might be without the previous and next frames from SOHO...the amount of time, movement (if any), particles in the area, etc are all clues that we use to decode anomolous images like that.

If I were to simply guess, based on that one image, I'd have to say the linear streak is just a data glitch running at almost a perfect 45 degree angle (perfectly diagonal across the square nature of a pixel) across several pixels. Since it seems to only be 1 pixel wide, it's apparent orange color, instead of white like other pixel defects, is due to bleed-over from the non-affected pixels around it.

JackC
2003-May-27, 09:38 PM
Brad

I was taking a closer look a bit ago and noticed that there appears to me to be a distinct brightening at the very top, left end of the trace, then again just below the flare or prominance (think it is a flare - don't have it to look at right now though) and again a third time about halfway between the second "brightening" and the sun. This brightening is very regular, if it is, indeed, a brightening at all and not an artifact of the pixel issue you mentioned.

If I were guessing based solely on this, I would say some small tumbling object of space debris within the field of the camera. But I know so very little about SOHO - such as it's exposure time, etc.

You are quite right about needing to see the prior and following shots. I think they wuold be interesting. Is it possible to find the originals on the SOHO site? Might be an interesting study.

Jack

Comixx
2003-May-27, 11:24 PM
Sure, it is possible to find the originals if we knew the date or the actual SOHO image catalog number of the one in the OP...but since that woowoo site renumbers them after they (illegally) copy them into their own domain, it makes researching them all the more difficult...which is probably one of the reasons they do it. As the BA and many others have pointed out, hoaxers hate to be debunked, so they strictly limit the available information.

I wouldn't completely discount tumbling debris near the SOHO satellite either, as you mentioned. Lots of ice and such gets blown around as the satellite maintains position...