Two things are infinite: the universe and human stupidity; and I'm not sure about the the universe.

Started Sep 19, 2013 | Discussions thread
Flat view
bobn2 Forum Pro • Posts: 56,095
Two things are infinite: the universe and human stupidity; and I'm not sure about the the universe.

So said Albert Einstein. Thanks to his ghost for a practical demonstration of the principle. Anyway, the 150 post limit unfortunately interrupted him in full flow in this thread, but we can always carry on in a new thread, so here goes:

EinsteinsGhost wrote:

bobn2 wrote:

EinsteinsGhost wrote:

I can't tell. I'm curious to see it in practice because talk is cheap.

So, you prefer to fill a grid with EV values and try to interpret a scene from that? The reason the camera doesn't generate the image going through an intermediary calculation of EV values is that it is a complete waste of time and effort, one that I don't intend to do myself. Conversely, a lightmeter that gives its output in arbitrary 'ADU' is also a waste of time. So, a camera is not a lightmeter and a lightmeter is not a camera. Case closed on that bit of your obfuscation, I think.

Nobody has suggested that light meter is a camera or a camera is a light meter.

Except for you 'BTW, your camera works like a light meter.'

So if there is an issue of obfuscation, you might first want to check into your own self.

Had a look. Let me see. No, it was you.

Why do you have this obsession with light meters? We're thinking about taking pictures here, not going around measuring the light. A light meter is simply a tool to assist photography, it isn't the thing that takes the picture. So what matters is how a camera works, not how a light meter works.

Aah, so now you want to avoid having a discussion on metering because your argument falls flat on the ideas you have been believing in for quite some time (obviously).

No, I want to avoid having a discussion about irrelevancies. We are talking about how cameras work, not how light meters work.

Why are light meters used? Does your camera not have one?

Most of my cameras have light meters and I also have several hand held ones. What you use them for is measuring the level of illuminance from the subject in order to help you select an exposure, did you think that they were used for anything else? Taking photographs maybe? Just a little hint, an instrument that does that is called a 'camera'.

And after the attempted obfuscation and pointless argument comes this. Okay, so you measure light and take photographs. Who knew that? The key to discussion is, how you use your light meter (or camera readings) into taking photograph. You didn't want to address that. Unfortunately, you will also be getting away with it in this thread as it has been filled with a lot of non-sense.

Mostly you were the author of it. Seems a bit rich to be complaining now. Anyhow, I have a solution. Still, you wanted to know how I use the light meter. Well, simples. I use it to check the light level which helps me judge my exposure settings. generally I'm aiming for maximum exposure, so generally it comes into play when the lights bright and I'm risking blowing the bright bits. Then I reduce exposure - in general by using a faster shutter speed, unless I'm going for motion blur, when I'll close down the aperture.

BTW, your camera works like a light meter. But you don't want to hear that, right?

Because it is not true. True is that both instruments measure luminance. There the resemblance ends. And the equivalence that you wish to assert is far beyond that divergence. What you try to assert is that 'exposure' measured by way of ISO and EV is fundamental to photography. Well, it isn't. There are many units you could use for exposure as well as the aforementioned ISO/EV or the APEX brightness units, such as stilb hours, foot-lambert centuries or lux seconds (which is what you;d use under the SI system). None of those units is 'fundamental'. What is fundamental is that exposure is the illuminance at the image plane integrated over the exposure time. The exposure meter becomes an exposure meter by measuring that and expressing it in units familiar (but not fundamental) to photographers. A camera samples that, producing and array on measured illuminance/time values (also sorted according to spectral distribution) which it stores as a set of arbitrarily scaled values in a raw file. Those values may be used to produce and output image with a desired distribution of tonal values (remembering that a tonal value is not the same thing as 'exposure'). What the ISO exposure index does is map exposures to tonal values - the ISO understand both what exposure is and what exposure index is. You seem from what you post to understand neither.

Cut the crap and tell me how you compose and set up your exposure. It would help if you posted couple of samples in different modes.

I compose and set up exposure in order to capture as much information from the scene that I'm capturing as I can. That generally means getting the bright bits just to the point of clipping. For instance for a shot like this...

Appreciate your examples, but useless to the discussion at hand: exposure variables.

Choice of exposure played rather a big role in both those shots, for the reasons stated. Still maybe you need to learn a bit more before you realise just how pertinent they are.

I would distinctly care for auto ISO. The thing is though, I have three cameras with decent auto ISO functions, but none needs it. I have one in dire need of auto ISO but it doesn't have it.

Because? (that needed to be the key to your response)

Presumably because the manufacturer (Canon in this case) didn't see the need. They were wrong, but then Canon has never quite got auto ISO.

No I don't (never had the opportunity, and I find basketball one of the most boring sports around). I do shoot motorcycles, however.

Even though photography has been merely a hobby of mine, I seem to have a different take on the situations it can present. Its not about whether you find something boring or not, as long as you're enjoying (or making money doing so) and taking advantage of a situation. But, I might be getting carried away... so back on track: since you have not cared for photography at NBA game, I can't expect you to know the basic settings much less rely on them with some experience to go with it.

So the premise here is unless you shoot NBA, you don't know anything about exposure. Interesting idea, but can't see how you arrive at it.

If you do, what settings did you use? And why? Knowing what and why YOU do something might help you understand why others might.

As I remember, the shutter speed was about 1/60 - to get a decent amount of background blur as I panned. The f-number was f/5.6. It was an f/4 lens with a 1.4x TC and I used it wide open - trusting the AF to focus well enough that I wouldn't need any more DOF. I used it wide open because the light wasn't so good and I wanted to maximise exposure. then I shot away.

And Auto ISO? Manual ISO? Or did you have camera sensitivity turn off magically?

I used the sensitivity the camera was made with.

And what led camera to decide on 1/60s?

The camera didn't decide on 1/60s. I did. The manufacturers thoughtfully endowed my camera with a little wheel on the back. Turn it, and the shutter speed changes. Maybe you should think of getting a camera with one.

-- hide signature --


Flat view
Post (hide subjects) Posted by
(unknown member)
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow