To find that out there is a simple experiment that everybody with a camera and a lens can replicate at home. With the camera in neutral settings, point it at a rectangular object from an oblique angle, like the table in my Figure 2, such that it almost fills the ground glass from top to bottom, and focus in the middle of it. Then use only front tilt to make the plane of focus flush with the object (and adjust focus as necessary). As you will see, the proportions of the object don't change. Set the front back in neutral position and now use back tilt to adjust the plane of focus. Consequentially, the part of the object close to the camera looks wider and bigger than before. This elementary knowledge on LF camera's is also illustrated in Simmons Using The View Camera (2nd ed) pp. 59-60. For photographs of people, it implies that when using back tilt on the horizontal axis, a face will look fatter than it is, and when using back tilt on the vertical axis, like in Fig.2, arms (or legs) will look disproportionally long. If such a distortion is not a deliberate and desired effect, like it was in Fig.2, use front movements, exactly like I said. No problem after all.
If you're still taking revisions, there is another contradiction to address:
Distribution of sharpness and lens personality
Although lenses of the same type and brand differ somewhat in sharpness across specimen and across focal lengths, they typically show up a highly similar distribution of sharpness (1) over their apertures (e.g. optimal at f16–f22), (2) over distance (e.g. optimized for short range), and (3) over the center-to-edge range (e.g. sharp almost to the edge versus only in the center); and, they have the same characteristics for bokeh, color rendition, contrast, and flare, that together determine skin tones. We may thus speak about the personality of a lens in terms of these traits.
This seems to be in conflict with:
To get great bokeh, there are much cheaper lenses than the Lanthar, among others some Tessars. Tessars have been built for over a century by many different factories, creating a wide variety of lens personalities with not many family traits that all of them share, perhaps only their bokeh, which is better than Plasmats’. Other traits, e.g. color, flare, distribution of sharpness, and contrast differ considerably, and not all Tessars are suitable for portraits, as we will see
Point taken, thanks.
I told myself I wouldn’t get drawn back into this, but I hate having people edit my words selectively.
I specifically differentiated between front movements for architectural purposes and rear movements for portraiture, something you edited out. In architecture, corrections are made with front movements when even slight distortions of straight parallel lines are critical. This comes at the expense of taking the lens off its optical axis, ie, it is no longer pointing at the center of the film, and you risk working at or beyond the edges of the image circle.
Yes, let’s look at your figure 2 as an example. You used a 150mm Sironar-S with a 231mm image circle on the 5x7 format that has an image circle of 210mm. You’ve got about 10mm, less than half an inch, for movement at each corner. By going outside the area of coverage and into just the area of illumination, you’ve sacrificed resolution to a degree obvious in even a web image, let alone a print. And that’s with a relatively wide-covering plasmat. Try it with a Ronar or Tessar, and you wouldn’t even have illumination.
The human face and figure have no grid of parallel lines to worry about. Without geometric grids, the amount of distortion that will occur from using normal rear movements is not apparent to the human eye. (What is very apparent to the eye is the spatial distortion you introduced by using such a short lens for a portrait with the hand so extended forward as to make it unnaturally large, an irony in an example of how to avoid distortions and preserve proportions...)
Trying to put it very, very simply, the concerns that are critical with straight, parallel lines of architecture are secondary to keeping a lens on axis in portraiture where there are no geometric lines to worry about.
This is one reason why dedicated large format studio portrait cameras, from the E&HT Anthony Portrait Cameras of the 1880’s, through all the Century Studio Cameras of the early 20th century, to the last of the studio cameras, the B&J Rembrandt Portrait Cameras and Master Pictorialist Cameras of the 1950’s and 60’s, were made with no front movements.
Seriously, setting all my points aside, do you claim to know more about what is necessary in a portrait camera than multiple generations of camera builders and professional portrait photographers working across the golden age of large format portraiture? (Somehow, I don’t think this will be answered…)
If someone comes from your site where you’ve linked to your article on “mostly old lenses”, they will believe that:
1.) They are learning about “old” lenses. (They are not.)
2.) If one is interested in “bokeh”, (a word your article used 51 times), a good recommendation is: “If the sitter can't stay motionless and I want to bet on the safe side, I use f16 or f22.” (There are multiple techniques to helping a subject stay motionless, and one need not sacrifice aesthetic control.)
3.) Century Studio Cameras (and others like them) are not adequate for portraiture because “you have to use mostly front movements”. (It is arguably one of the best choices one could make for studio portraiture.)
BTW, regarding your Lanthar, which you say "looks as if this lens has inbuilt yellow and green filters," and as a result, "The Lanthar’s color rendition is weird, looks like 17th century paintings, and needs Photoshop correction." The Lanthar's radioactive glass yellows over time due to radiation tracks in the glass, and can be bleached by leaving it in the sun for a few days.
"I love my Verito lens, but I always have to sharpen everything in Photoshop..."
...and to the rest of the forum, I apologize. It was a long day...
"I love my Verito lens, but I always have to sharpen everything in Photoshop..."
Multiple points to be addressed, for which I change the order.
Thanks for reminding me of bleaching the glass in UV light. I had read it years ago, then forgot about it, and will now try it. Depending on how good this works, I'll mention it in the next version.
Shift is not the first camera movement that comes to my mind for portraits (although I use it if a person is in front of a building), as the prime target is (usually) to get the eyes sharp, for which tilts are necessary. Any more back tilt than a very little I do notice, as well as disgruntled sitters did on whom I tried this. The experiment I described in my previous message everyone can replicate at home to verify the distortion I talk about. Why did those studio portrait camera's back in the fifties that you mention only have back movements? Were image circles typically small, or were only little movements used? By the way, if we would have to deal with shift only, then shifting the front up or the back down amounts to exactly the same result, so then one of them can be left off the camera.
Electrical guitars were initially not invented for rock 'n roll, and when they started being used for that new genre, some complained about the distortion and noise. We all know how that story continued. In general, finding new applications for existing materials is part of the creative process. The text in my article describes how to make portraits without distortions first, i.e. by using front movements, and when the novice knows this, (s)he can subsequently do whatever (s)he wants. For as long as some art collectors love my near-far portraits with the Sironar-S, and you don't pay my bills, I continue to use my Sironar-S beyond it's initial purposes and limitations. By the way, the 231mm image circle is at infinity, but at the close range where I work I have more.
Bokeh and focus.
The word bokeh (with some explication added) concisely summarizes what one wants for a portrait lens without going overboard on the technicalities of spherical aberration. For a portrait, even at f22, there is plenty of unsharp background that one wants it for.
In the article, there are multiple examples and mentioning in the text of portraits shot wide open before the reader reaches the sentence: “If the sitter can't stay motionless and I want to bet on the safe side, I use f16 or f22.” For sitters in difficult positions, multiple sitters who move with respect to each other (Fig 15), or non-cooperative ones, my advice makes it possible to get the eyes sharp. Additionally, many contemporary photographers want the entire face sharp, not only the eyes, and they deliberately use smaller apertures (e.g. the highly successful Rineke Dijkstra, among many others). So what's the loss of aesthetic control for you is the gain of it for others. But the world is big enough to contain a diversity of aesthetic views.
Due to your earlier remarks, I've made it clear at the start that the article is about lenses that their manufacturers mounted in shutters. Experts then know that it's about more recent lenses than those from the "brass age" of photography. On my personal webpage outside the LF-domain I can write whatever I want, though, and for that matter say that I import my lenses from Saturn and use its rings as retainers. I say there that my lenses are old not only because most people think they are, but mainly because compared to their lenses, most of mine are actually relatively old.
Well, thanks to you moderaters. I can take off my flame proof suit now!
Yes the 'golden age' folks WOULD build, and gladly use, front tilt and swing cameras - if only they had a chance....