Hyperfocal distancecalculator

Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Equivalentfocallengthcalculator

In older images, another factor may enter into a "soft contrast" image: lens flare. Prior to the early 1940s, lenses did not receive anti-reflection coatings (the process hadn't been invented yet), so each glass surface interface resulted in light scattering, which (especially with a bright area in view relative to the main exposure) tended to fill in shadow areas and reduce overall contrast. This is also why pre-War lenses were usually designed to avoid high element counts -- triplets, 4-element Tessar types and 5-element Heliars, the largest element count that was at all common before 1945 was the six-element Xenon (I have one, it's an awesome lens, but it does flare some against the light).

Lens calculator

Copyright 2023, Edmund Optics Inc., 14F., No.83, Sec. 4, Wenxin Road, Beitun District , Taichung City 406, Taiwan (R.O.C.)

Focallength to angle of viewcalculator

Any particular suggestions, explanations on what went on to achieve the images, or aid would be greatly appreciated. Thank you!

Relate optical and mechanical parameters of simple lenses in order to ease integration into application assemblies. Select index from list of Edmund Optics' own optical substrates to help calculate focal lengths and principal points of any standard lens.

Focallength estimation

I'm new to film photography (~4 months in) and happened to have questions regarding on how to achieve a particular look. I'm not necessarily looking to emulate the look, rather, understand what went into it and how those particular choices influenced the outcome of the images. Here are a couple of examples:

I remember reading somewhere how, for the Edward Weston one, one could achieve the "soft focus" look through the means of a pantyhose or a bit of vaseline rubbed around one's lens, but as for the other ones, I have no clue.

Going along with this is the need to expose more in order to provide correct high values in the positive (print or scan). Together, exposing more and developing less are referred to as a "pull" -- the opposite of "push" in which film is knowingly underexposed and overdeveloped to compensate (perhaps because the light level is too low for the available film and lens combination, or perhaps in order to boost contrast on a low contrast scene).

How does one achieve that hazy, soft, low-contrast, but, at the same time, somewhat overexposed look? Is this something that one would achieve while shooting? In the darkroom?

Reduced contrast is generally achieved with film by developing less than "normal" -- this produces a lower slope on the linear portion of H/D plot (that is, less increase in negative density for a given increase in log exposure), which we see as less contrast. In Zone terms, by developing less, you keep the low zones nearly the same, but the higher exposure zones develop to lower values.

One relatively common application of pull processing is to produce a "high key" image -- low contrast development combined with higher than normal exposure, then printing at high contrast to bring out only selected features of the image.