These two photos were taken in 1988 at the Hotel Vierjahreszeiten in Maurach, Austria. Several vacationers gathered for a farewell party at the hotel and decided to take a group photo.  

One of the party, Mr. Todd, set up is Canon film camera on a nearby table and pointed it at the group. (The table is the white band at the bottom of the photos.) He set the self-timer on the camera and hurried back to the table. The shutter clicked and the film wound forward, but the flash did not fire. So Todd set the camera for a second shot. This time the flash fired. 

The film was later developed, and it wasn't until one of party members was viewing the photos that it was noticed that the first (non-flash) photo showed a somewhat blurry extra head! (In the sequence above, the second (flash) photo is actually shown first for the sake of comparison.) 

No one recognized the ghostly woman, and they could not imagine how her image appeared in the picture. Besides being a bit out of focus, the woman's head is also too large compared to the other vacationers, unless she is sitting closer to the camera, which would put her in the middle of the table.  

The photo was examined by the Royal Photographic Society, the photographic department of Leicester University, and the Society for Psychical Research, all of which ruled out a double exposure as the cause 

2008 - JSPR (Guy Lyon Playfair) 

Even when we do have sufficient information, the best we can do is try to eliminate all possible normal causes of the apparent anomalies. Probably the most thoroughly investigated picture in this book is that of the mystery guest at the table of a group of holidaymakers in an Austrian hotel, who was visible on only one of several pictures taken at the time (pp. 104-105). 

Three SPR members, Maurice Grosse, Vernon Harrison and this reviewer, spent a good deal of time examining the original negative and interviewing eight of the eleven witnesses unusually large number all of whom gave verbal statements or signed written ones to the effect that they had no idea who the extra woman was, and did not see her at the time the picture was taken. 

The photographer also signed a notarised affidavit stating that the account I gave of the incident (Playfair, 1993) was true. Dr Harrison, a former Principal Scientist at Thomas de la Rue and specialist in detection of forgery, made a careful study of the original negative, and described the print as one of the most mysterious photos I have seen. I can't think of any plausible explanation." (written statement in SPR archives) Nor to date can anybody else. I can, however, clear up a minor mystery. As Willin points out in his commentary (p.104), the women next to the phantom seemed to have moved their seats as if to allow the extra face to appear between the two. Many have found this suspicious, so I questioned both women separately and each explained that they could not have moved their seats as they were jammed together, but one of them had leaned forward to relieve the pressure on her shoulders. 

Yet, sadly, we remain none the wiser as to who the woman was, or whether she was a genuine ghost, spirit or (my preference) a Doppelgänger of the woman on her left, who, incidentally, told me she thought it was her guardian angel. There is definitely an extra figure in this picture, but all we can establish, at least to our satisfaction, is what she was not; for example, a cardboard cut-out (the wall covering can be seen through her hair).

References

Playfair, G. L (1981) A ghost hunter's guide. The Unexplained 34, 678-680.

Playfair, G. L. (1993) The mystery woman of Maurach. Fate (October), 65-70.

One day in the summer of 1988, David and Carol Agnew dropped in to see George and Ella Todd, whom they had met on their Easter holiday trip to the Austrian village of Maurach. George had taken along his Canon T50 camera, and shot several rolls of film. When they were developed, he took a quick look through them and put them away in a drawer, never giving them another thought, until Carol asked if she could see them.

She began to go through the film George had taken on their last night at the hotel, where a group including the Todds, the Agnews, and seven other tourists had put a couple of tables together for their final meal, after which they ordered some drinks and waited for the floor show to begin.

She came across the picture George had taken of the whole group and saw that it was darker than the others. This was because the flash had not gone off, he remembered, so he had recharged it and taken another photo which came out perfectly. There was something strange about the one before, though. There were too many people in it.

Even without the flashlight, there had been enough light in the room for the automatic camera to take a slightly longer exposure, and come up with a picture in which all members of the group except one, who was just out of Frame, could be easily identified. But who was that in the middle of the group?

It was a woman dressed in white who seemed slightly larger than the others, and was also slightly out of focus. This was hard to explain in itself, as everybody else in the picture was in perfect focus. Even harder to explain was: who on earth was she?

“I felt cold and goose-pimply” Carol told a researcher later. “That,” she had said to George, “is a ghost”. And today, more than ten years later, that is also the conclusion of a good many of those who have seen the picture reproduced in several newspapers and shown twice on television. The print and the negative have been scrutinised by Dr Vernon Harrison, former chief scientist with the De La Rue banknote company and one of Britain’s most experienced forgery detectives. His opinion: “One of the, most mysterious photos I have seen. I can’t think of any plausible explanation.” Nor can anybody else, it seems.

Eight members of the group have been tracked down by members of the Society for Psychical Research and questioned at length. They have all signed statements to the effect that they were not up to any trickery, they haven’t a clue who the mystery woman is (or was), and they had not seen her at the time or before, or since. The only possible solution so far was suggested by one of the SPR investigators.

“It looks to me Like Ella Todd’s doppelganger, or double,” he told me. “Her hairstyle and general features are similar to Mrs Todd’s, although her dress is white and Ella’s is dark. This may be the first time anyone has photographed a double since William Mumler a century ago, but several people have seen them, including Goethe and Maupassant who saw their own doubles. Then there are at least five Roman Catholic saints who were quite reliably reported as having, been seen in two places at once.”

Source: http://www.urigeller.com/uri-gellers-extended-reality/ 

1 - L'apparition émet de la lumière visible å l'appareil et invisible pour les témoins

2 - Le rendu physique est parfait sauf pour le flou

3 - Il y a clairement le signe de la volonté de "participer" 

Discussion : http://everythingghost.co.uk/forum/viewtopic.php?f=15&t=835&sid=fa1bb20b32922338e10f0f94ba2814f8