Ghost, or ???

posted November 16th, 2012
Please check out these three pictures and tell me your opinion on what the anomaly is on the left side, covering St. Peter's right foot? I have the original unedited photo, a lighter version of it, and a lighter cropped. Explanations are on the photos on my project.
Thanks!





posted November 16th, 2012
Oh my goodness. How fascinating. There's either some fancy editing going on or there was a person there that didn't turn out clear in the shot or you might have a ghost.
posted November 16th, 2012
@mittens The only editing is making the original photo lighter. The unedited version is the top one that is darker. At first, I thought it was just someone walking in front of the foot, and that's why I couldn't see it. When I lightened the photo, this is what I saw.
posted November 16th, 2012
camera info please? Like shutter speed etc...
posted November 16th, 2012
It's because you used handheld twilight mode. The camera takes six exposures and combines them into one HDR'd, low(er) noise final image. The person on the left was moving through the frame during the six exposures, and the camera has chosen to use some parts of the image where she was standing in that location to make the final photograph.
posted November 16th, 2012
Ghosts? lol. Nah, there's clearly some double exposure going on.
@abirkill that is more than plausable.
posted November 17th, 2012
@bobfoto Camera: Sony SLT-A65V
Exposure: 0.0167 sec (1/60)
Aperture: f/4.5
ISO Speed: 1600
Focal Length: 26 mm
Date Taken: 2012-10-13 13:52:14
Date Uploaded: 2012-11-16 12:57:49
File Name: DSC01843.JPG
File Size: 7.13 MB
Image Width: 6000 px
Image Height: 4000 px
X Resolution: 350 dpi
Y Resolution: 350 dpi

@abirkill It's definitely possible; I'm not sure I used hand held twilight: I'm thinking now that if I had used it, the resulting picture shouldn't have been so dark. But I think I'll do some experimenting and see if I can duplicate the result. None of my other pictures that I took (more than 2600) came out like this, and I used multiple settings. Also will look around online to see if anyone has had weird hand held twilight results.
@intymalcolm Some people believe, some people don't. I've had enough weird and unexplained experiences (as have my mom and aunt) that I DO believe! Never say never... =-)
posted November 17th, 2012
@2thgirl The artifacts in the photo are entirely characteristic of HDR processing that isn't eliminating ghosting, which is exactly what handheld twilight mode does. If you want to eliminate ghosting from your images, Sony suggest that you use anti-motion blur mode, but bear in mind the image quality will be lower.

The original photo's EXIF data will have recorded whether it was taken in Handheld Twilight mode. You can confirm this by uploading the original image to this website:
http://regex.info/exif.cgi

It'll bring back a large amount of data, but if you search for 'Release Mode 2' and 'Exposure Mode' you'll be able to confirm what setting the camera was on.
posted November 17th, 2012
Here's my ghost:
posted November 17th, 2012
@abirkill Oh, cool! I'll check it out!
posted November 17th, 2012
@abirkill Holy cow, that DOES give a lot of info!! In sifting through it all, I see that it WAS in handheld twilight, and the anti-blur is also ON. So it appears someone somehow walked fast enough out of the frame that it only caught part of them on the sensor? How does this type of anomaly occur?
And, thanks for the link! that's pretty cool!
posted November 17th, 2012
@2thgirl It's quite scary how much hidden info is in the files, isn't it! Especially with more and more cameras having GPS built in -- a lot of people aren't aware that their photos often contain location information accurate to within a few metres!

Basically, when in twilight mode, the camera takes six exposures at different settings, and combines them to form an HDR (high dynamic range) image, picking areas from each photo with the most detail and least noise. This single, combined image is what you end up with when you download the photos from the camera.

At least some of the six images would have had the mystery person in them as she walked past. Because the camera is trying to maximise detail in the image, it will pick little bits of the person in different places to incorporate into the final photo. Bits with high detail, such as the bright red bag, scarf or similar item we see at the bottom of the frame, will be particularly favoured by the camera's algorithm as it thinks that they are highly detailed, whereas bits with little detail, such as dark clothing or hair, will be ignored if there is another photo with more detail in that area. This patchwork-type ghosting is not uncommon when creating HDR images with movement in them.

HDR software typically has an option to reduce ghosting when processing the images, where it will attempt to identify objects which move or disappear between the different component frames, and compensate for them (typically by adjusting a higher or lower exposure image to fill in the suspect area). However, this is quite a complex procedure, which can take several seconds to complete on a modern PC, so to do it in camera is usually either not attempted, or has limited success.

The photo from @pengu1n shows more typical ghosting as you see with a single long exposure -- the person was stood in that location for approximately half of the length of the exposure, and was moving quickly enough during the other half of the exposure not to show up. Because the camera isn't doing any processing -- it's just capturing the light over a prolonged period -- the result has none of the patchiness of the HDR ghost image.
posted November 17th, 2012
@abirkill Thanks for the explanation! I am new to anything beyond point n shoot photography, and have little abilities in editing, so my knowledge base is very limited here! This is why I posted the pic here, knowing I'd get a fair amount of juvenile criticisms/jabbing and hoping somewhere along the way someone would give me a viable explanation! Thanks again! =-)
posted November 17th, 2012
@abirkill Oh, and I normally have the GPS turned off because I heard how the info can be extracted and people can find out where you live. I turned it on before I went to Italy so I'd know exactly where each pic was taken. The GPS didn't always register (ie, the satellite couldn't "see" me), but most of them did. But it also reminds me to turn it off again!
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