Metering Blacktop

Discussion in 'Casual Photo Conversations' started by denny_rane, Sep 20, 2021.

  1. For some reason i have never done it.
    I have metered cement, my hand, a few different pairs of shorts that are virtual gray-cars, but never blacktop.

    For "Typical" blacktop that is a few years old, like in a parking lot, what Zone does it seem to fall in, 3...4...5.?
    Thank You
  2. Wet? Dry? Lit at a high angle? Or a low one? All these factors, and more, will change its reflectance by a factor of 10 or more. It has no standard Reflectance.

    And surely the whole point of the Zone system is to place an object's tone exactly where you want it to be? Otherwise you might just as well take an incident reading and be done with it.
  3. Digital camera? Just take the photo and adjust exposure to taste. If film, you could apply the "Sunny 16" rule. Worked well enough for slides.
  4. Unless you're shooting transparency films, film latitude and sunny-16 will almost always produce adequate images, especially if you're scanning them in.
    Digital? forgedaboutit. Use the sliders in post processing.

    rodeo_joe asks the right questions, as he often does.:rolleyes:
  5. But like many gurus, mystics and wise men on top of the mountain, his questions probably have no answers. :) I've seen blacktop in just about every shade, from bleached to very black. Whether it's been sealed recently will make a huge difference. Put it in any Zone that works.
    AJG and Ed_Ingold like this.
  6. Asphalt can range from dark (5) to light gray (8). Do you care what it is? Asphalt makes an uninteresting subject. When in doubt measure the palm of your hand (8) or use an incident meter.
  7. I was just, simply, curious.
    I shoot 35mm film but that is meaningless.
    Blacktop top "during the day" compared to a gray card.
  8. Green foliage (grass, tree leaves, shrubs, etc.) is a good grey card substitute.
  9. r_ j has a very lucid response for day or night.
  10. As was mentioned, "blacktop" has MANY different shades, from very faded light grey to BLACK. Age, the other "stuff" in the blacktop, and the amount of visible asphalt affect how light or dark it is. What shade of grey/black is YOUR blacktop?
  11. Not sure if that's a compliment or a sideways insult. I don't mind either way Conrad, but I lay no claim to anything more than a (hopefully bit less than) lifetime's involvement with photography.

    If you want some more mysticism - The best answers make you question your own question.
  12. Wow.!
    You guys have some REALLY F'd Up blacktop where you live.
    We have 100s of miles of highway, county road and strip-mall pavement that is 97% the same color.
    Took several readings all hits about Zone-4.
    Well, now i know. :)
  13. @rodeo_joe|1 - Hey, nothing but the greatest respect here. We fossils have to stick together.

    As for our blacktop, this is the northeast, where everything gets weathered, not to mention it's salt country. The sealer guys have all been out in force the last few weeks, getting driveways ready for winter. I wanted to say guys & gals but I've never seen a gal sealing a driveway. Ever.
    denny_rane likes this.
  14. "Black" top can really be a range of tones as Rodeo_Joe and other stated. But if you want a rule of thumb of where it might be, take a tonal Zone chart in your bag, and just eyeball it and meter accordingly. If you just want a decent exposure you can use and averaging meter or just use the sunny 16 rule. I agree with JDM, with most film lattitude, especially b/w as long as its decently close it will be fine. When shooting digitally, you can, if your camera lets you, set your exposure mode on spot and use your wysiwyg finder and you can just move it around and set the exposure wherever it looks good to you, sort of an instant visual zone system. If you are using medium format or large format, especially large format, using the zone system is the way to go, I would say.
  15. Not to labour the point... But.
    There aren't many real life objects that even get close to being true black - i. e. having zero or very little Reflectance.

    Closest you're likely to get 'out in the wild' is probably something like 2% reflectance (maybe an animal with black fur or someone's black woollen coat). Which is just under Zone 2, taking 18% Reflectance as Zone 5. So Zone 4 makes it "Darkgraytop", rather than Blacktop.:cool:

    However, a rainy day will soon change all that, and reflections from a wet and shiny surface can have almost any possible Zone value.

    Just stick to TTL or incident metering. Even Saint Ansel couldn't get his Zone number sums to add up straight!
    Last edited: Sep 23, 2021
  16. I am pretty much a "Street Photographer".
    And yeah, i use the camera meter 99% of the time.
    Generally speaking, i am either in some type of sun or some type of shade. I meter both and usually do not take another reading unless the light changes pretty drastically.

    The "Blacktop" question was merely academic. It is so ubiquitous, i was surprised i had never metered it before.
    I carry an incident meter, but i rarely use it.
    In the right situation though, i am glad to have it.

Share This Page