Not much is revealed about Fritz's personal life in any of the Say Cheese and Die canon, other than he assisted in building 'The Camera' in his 'youth', and that he is considered to be old by the time the events involving Greg and his friends occur (though his exact age is not revealed, he is initially estimated by the children to be '50 or 60', and at the end of the book 'Say Cheese and Die' Greg and Shari describe him to be 'much older' than 60, though they judge this solely by his face and admit his voice to sound 'younger than he looked'). At some point he must have attended both College (for an advanced level qualification) and University (to attain a degree, Masters level, and then a Doctorate), though what field he is a qualified doctor in isn't revealed (it is likely to be scientific in nature, potentially in Mechanics or Photology). He was likely born in at least the 1920s, going by Greg and Shari's final estimation. At the beginning of 'Say Cheese and Die', the children describe having seen him 'around town' from a distance. Based upon viewing his appearance from some distance, they suspect him of being between '50 or 60' years old, stating that many others in the town hold this to be true. When Greg and Shari are trapped by him at the book version of 'Say Cheese and Die's' climax, him blocking their escape from his basement dwelling in the Coffman House, he removes his 'black baseball cap' and thus reveals his previously shadowed face. Being the first two people in Pitts Landing to see his face (the earlier statement that others in Pitts Landing think Spidey is between 50 and 60 suggests no one has seen his face close before) Greg and Shari both decide that he is older than 60. He was potentially in possession of some financial means in 1968, as the children find clothes in a wardrobe in the basement of Coffman House which appear to them to be 'at least 25 years old'. If the year of the events in the book 'Say Cheese and Die' are taken to occur when it was first published, 1993, then this dates the clothing to 1968. The clothes however, may have initially belonged to another person or people e.g. theatre cast offs, the Coffmans clothing etc... but nothing is clarified.
Dr. Fredericks is often referred to as 'Spidey' by those living in Pitts Landing. The nickname was apparently applied due to him appearing spider-like to many townsfolk, with 'spindly legs carrying him about' and him only ever being 'dressed in black'. The name seems to only have been used since he settled in Pitts Landing, and may have been catalyzed into use by the effect aging has had on him (his body is described to show striking evidence of what could be the aging process e.g. spindly, thin legs, and it possible that other parts of him look dilapidated and strange). It is also possible that due to him living in abandoned buildings (The Coffman House in the book 'Say Cheese and Die' and an industrial warehouse in the television episode of the same name) his behavior is considered to resemble that of a spider, as they are know to live in the most unpopulated areas. He also could be considered spider-like in his movements, moving sporadically in the television episode 'Say Cheese and Die', and seeming to scuttle out from nowhere obvious at times during both the book and television episode. He also has a habit of observing others, especially Greg Banks, from secluded areas. Whether or not he looked spider-like in his youth is unknown, as no one in the town seems to have known him then (He appears to have moved to the town simply hoping to live the remainder of his life quietly, concealing 'The Camera' from others, therefore perhaps has intentionally made sure no one knows anything about him).
Involvement with the camera
From what is revealed in the Say Cheese and Die canon, Dr. Fredericks is indirectly responsible for triggering much of the events of the first book, 'Say Cheese and Die', as well as those occurring in the television episode of the same name. At some point 'in his youth', Dr. Fredericks obtained employment in a laboratory with another man, who was currently working on a Camerology project. The man was constructing a camera (later to become 'The Camera') which Dr. Fredericks was hired to assist with the development of. Whatever the cause (Dr. Fredericks may have been angry that he had been hired simply to provide what he likely thought of as 'insignificant graduate-level support' to the Camerologist) Dr. Fredericks ill feeling towards his work in the lab led him to covet this device, which he interpreted as 'the best camera ever made'. Likely excited by the prospect of fame and fortune that was almost certain to be awarded to its creator, Dr. Fredericks waited until the camera was finished, and then immediately stole it at the best opportunity available. Once Dr. Fredericks had the camera in his exclusive possession, he likely plotted how to present it to the world, claiming himself the sole inventor. The real creator was angered by Dr. Fredericks actions and so placed a dark magic curse on the device, transforming it into 'The Camera'. Dr. Fredericks somehow knew that The Camera's creator had done something to taint The Camera, but he apparently did not understand the nature of the taint until after he had tested its image definition by photographing 'people he loved'. Sadly, those he photographed either died or were severely harmed, leading him to leave his life and become a vagrant, wandering America filled with guilt. Evidently, wherever he tried to settle, The Camera led him into further misfortune, until he eventually arrived in Pitts Landing, which was to be his last home in life.
It appears that Dr. Fredericks involvement with 'The Camera' has taken its toll on his mind. Specifically, he suffers from paranoid and depressive symptoms (depression is evident when he speaks of the punishment he feels the camera has laden on him, by killing those he loved, and the paranoia appears when he considers it reasonable to keep Greg and Shari locked up in his dwelling, so they will not 'blab about the camera'. This is paranoid because they haven't suggested at any point that they will tell others about its powers, and keeping children prisoners is a serious action).
The fate of Spidey differs depending on which source is engaged. In the book "Say Cheese and Die", Spidey is accidentally killed by Shari in the Coffman House, who he fights with for possession of the camera. During the skirmish, Spidey's picture is unintentionally taken, causing him to 'die of fright' as the book states it (it is likely to be the case that his exact cause of death was myocardial infarction, better known as a heart attack, and it is likely that the camera caused it).
The television adaptation of "Say Cheese and Die" differs, in that when Spidey's picture is taken, he gets transported inside the camera and then accidentally released by the two bullies when they find the camera. Consequently, he is still alive at the end of the episode. Despite this, he doesn't appear in "Say Cheese and Die - Again" except in flashback, though he may have gone off searching for a new hideout as the warehouse was about to be occupied.