Strange on camera image

Yesterday I finally got the Christmas tree taken down, reboxed and brought upstairs. The tree is kept in a small (use to be trunkroom) at the end of the upstairs western hallway. The room is rather small, about 10ft by 10ft and is rather crowded with seasonal (mostly Christmas) decorations. As I was manuvering the tree box into place I heard a loud noise from something hitting the floor. Looking around I spied an old spy camera I had placed in that room looking down the upstairs hall. I had forgotten about the camera completely until I saw it on the floor. Picking it up I immediately noticed the batteries were dead. I honestly do not know how long ago I placed that camera; but it has had to be a year or more. I opened the battery compartment and saw the batteries had leaked and I had corrosion. I discharged the bad batteries and hoped I could clean away the corrosion. Upon reentering the upstairs bedroom that is just off the hall, next to the Christmas room, I saw, in the middle of the floor, the dark outline of of I thought was one of my dogs that had found his/her way upstairs around the gate. Just as I said,"How did you get up here" the image vanished. The day was dark, dreary, and rainy. The bedroom is not overly bright even on a sunlit day and today it was dark as I hadn't as yet turned on any lights. The outline of a dog looked very much like a floppy eared schnauzer. I have had four floppy eared schnauzers since I moved here over 30 years ago. I have had one schnauzer with the cropped short pointed ears and two that had uncropped ears the stood up (or at least one ear did). I have had these sightings of dogs before; not always schnauzers, so I was surprised but not surprised when the image vanished. Getting back to the spy camera. The camera looks like an air freshner but is digital and takes pictures when movement is detected/ I took the camera downstairs to try and clean the terminals and get it working again. As I sat scrapping the terminals, I noticed the cameras chip. Out of curiousity I removed the chip and put it in my HP photo printer to see if it had anything on it. I was startled to see it registered "Full". In this case "Full" means 70 pictures. Remember I said the camera was only activated by movement. The first 30 or so shots were taken down the hallway and the last 30 or so shots were of the upstairs masterbedroom door. Obviously the camera had been knocked or moved sideways and was pointed at the door. I do not understand these door pictures as only two of them show any movent like the door being opened or shut. Anyway, its the upstairs hall pictures that could be interesting. Some appear to be totally black; so I don't understand what could have activated the camera in a totally dark hall. Some of the pictures show points of light where there are no light sources. Two show what appears to be vaporous or smoky forms. These last two really got my attention but they would not print out. They are very obvious on the monitor but nothing shows on the printout. They probably have a logical explaination; but the sheer doubt makes then intriguing. I do not know enough about digital cameras or printing proceedures to know how, or if, these can be brough out.