Blanquart-Evrard is famous because he invented the first commercialy popular photographic print process. This was called the albumen print which he created in the 1847. This process was made by putting a piece of paper in egg white and then drying under uv light and then is put directly under a negative image and you put i under direct light to get the image to go onto the paper.
After this process this is the type of image you would get.
This process was the starting point to lead on to more accessible photography.
Julia Margaret Cameron was seen as less scientific than most photographers of the time. She used a lot of soft-focus photography and saw photography as an art as well as a science. Because she manipulated the Wet Collodion process which made her photo be viewed as bad photography after it was finished with the albumen process.
Cameron these days is seen as a women who was ahead of her time because she photographed women and showed them as who they really were. These are some of Julia Margaret Cameron photo's.
To bring these type of photo to now you could use photoshop. This is a tutorial of how to make new picture look like this.