I am by no means an expert on the camera lens, and in many cases, the use of a view camera lens versus a modern lens used on a conventual fixed focal plane camera such as an SLR style camera, one needs to take in a few different aspects, such as the area covered on the focal plane as well as the focal length between the center of the lens to the focal plane. then before the invention of the iris type aperture, the lens was generally used as we now call it wide open, that is until it was realized that you could increase the depth of field by decreasing the size of the opening, through which the light traveled, this was accomplished through an action called stopping it down. however, this also increased how long it takes the light to travel through the lens, effectively increasing the exposure time by a stop. The 1st basic stops were nothing more than a washer-like disk that one needed to disassemble the lens to insert, later, slots were added to the lens to allow the user to insert the stops, rather than taking the lens apart. this later style was named after the inventor, a British astronomer John Waterhouse. AKA the Waterhouse Stop.
Using a combination of continuous lighting and strobe lighting, along with fresh collodion, I was able to take some, in my opinion, wonderful photos at the Tanners antique and craft show, this last weekend. I also got to show off, some of the neat aspects of using a Petzval formula portrait lens. The lens historically, was a purely mathematically purpose designed lens, to increase the speed of how the light traveled through the lens to allow the photographer to use nearly instantaneous exposures times to take portraits. However, the lens also had some artifacts. Those artifacts were very narrow focal area and shallow depth of field. Forcing the photographer to use large and heavy lenses, for very small sized images, those artifacts also helped expanded upon the argument as to what photography was, such as was it a science, was it art, or was it simply something to record history, creating multiple camps and ideas of what photography is or was, even today 178 years post the introduction of the daguerreotype, photography is still evolving, creating a greater separation between the artist and the technician, while adding digital artist, that digitally create new images based upon photographs
one of my more favored photographers from the 19th century, Julia Margaret Cameron, who was often frowned upon by the greater photographic societies, because she focused on using the tools that she had to manipulate light and focus, to express feelings and emotions, rather than creating a technical replica of the subject. As part of that, she, in my opinion, exploited one of the more difficult artifacts from the Petzval lens, bringing portrait photography to a new level of art while helping to create the portrait photographer.
The other artifact, from the Petzval lens, that is not something commonly seen in classic portraiture, as it was often considered distracting while marring the technical details of the photo, is what we call today as swirly bokeh. The effect is created by pushing a combination of the focus area and depth of field. It typically shows up at extreme edges of the focus area and near the infinity depth of focus, outside of the depth of field, beyond the focal point. In a studio like setting with a backdrop, the swirly bokeh doesn’t show up. However, this effect was occasionally used to enhance a focal point, or as an artifact, in some photos from the mid 19th century. most commonly when the photographer needed a very fast exposure, as compared to using a much slower lens such as a single aplanatic or the near pin-hole, wide angle lens.
That swirly bokeh effect, was considered more as an artifact of the lens, but it was also a signature of how the glass was ground and spaced, causing lens manufacturers to try a number of different experiments using similar element configurations to keep the speed, while eliminating the artifacts, thus making it very difficult if not impossible to recapture those effects using a modern lens. That is until a company called Lomography created what they call a modern Petzval, which is specifically to exploit the swirly bokeh effect, and in my opinion failing to understand the true nature of the lens.
here’s a review of the Lomography Petzval by Richard Wong
starting, in, I believe the 1860’s lens manufacturers such as Dallmeyer started allowing the photographer to adjust focal area, through the ability to unscrew in the rear element of the Petzval designed lens, effectively increasing or decreasing the air spaced gap between the rear elements of the lens. This effect allows the photographer to soften the focus, by decreasing the focal area, this effectively allows the photographer to focus on a specific point, keeping that point in perfect focus while throwing everything else out of focus. This effect turning about to be a wonderful effect principally used by portrait photographers such as Julia Margaret Cameron.
I truly enjoy using my Dallmeyer 2B, Patent Portrait lens, a lens made in 1876, using the Petzval formula, unfortunately, unless I get a volunteer, I don’t often get a chance to really play and work on doing much more than the generic, almost passport-like photo on a tintype
here are the two half-plate sized tintypes of twins taken using my Dallmeyer 2B, – while capture some neat lighting and soft focus effects, creating wonderful portraits.
The images seen here of the tintypes were taken using my cell phone prior to being varnished, and while still wet, as a result, the there are some weird reflections and exaggerations of the actual tones of the image.
please note, due to the particular fixer along with the developer formula I use, my images provide a little warmer brown tone, rather than the cold contemporary blue toned black & white images. This is compounded by the nature of tintype images, their true beauty is often visually impaired by the ambient light and its tones, remember artificial light, often has more red and brown tones in it, rather than being full spectrum. its then digitally flattened, removing the reflective qualities of the silver and varnish, while picking up color tones from the lighting that the image was rephotographed in using whatever camera was convenient in. please do not mistake using words such as it’s dark or very brown when comparing to images that have been scanned and digitally manipulated.
note, the video I shared on facebook of the video, of the tintype of my 1909 safety bicycle. the actual tones are the same.