Pls show examples where increasing brightness in post better than increasing ISO.

Started 9 months ago | Discussions thread
bobn2
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Re: Preferred compromise
In reply to Steen Bay, 9 months ago

Steen Bay wrote:

bobn2 wrote:

Steen Bay wrote:

bobn2 wrote:

In any case, even if it does, the rigmarole that they have gone through to get there is a whole lot longer than the simple route, set the aperture and shutter for the largest exposure that your pictorial constraints allow, set the ISO to get the brightness, according to your usual methods for 'nailing the exposure brightness' (mine are do it at my leisure on a nice big computer screen).

Don't think it works like that.

Yes it does.

It's always a compromise involving all three variables (DoF/diffraction, shake/blur and noise, represented by the f-stop, shutter speed and ISO),

No it isn't.

not just two of them.

Yes, just two.

OK, guess that's how it is then. Nice that we got that settled.

Glad you're learning, finally.

I wouldn't just choose a f-stop and shutter speed, and then let the noise in the final image be whatever it turns out to be.

Why would you not, when you know that the noise is the lowest that you will get with your other constraints.

Why are two of the constaints more important than the third?

Because the third is nothing, it's just the other two remixed. It gives you nothing extra.

Let's say that in low light I really don't want to use a slower shutter speed than 1/60 sec, but maybe that'll require ISO 3200 to get a 'properly exposed' image with the correct/preferred brightness, and then I'll maybe choose 1/30, ISO 1600 as the preferred compromise instead.

Why would you? The extra camera shake will damage your image more than the extra noise, guaranteed.

Didn't mention which camera. Things don't look pretty at ISO 3200 with e.g. a 5.6x crop compact.

Doesn't matter, when you trade a stop of shake versus a stop of noise, the stop of noise is always better, because it's always easier to remove. So, if you say 3200 is not pretty, it is prettier than 1600 with the shake. In any case, if you really were that picky about quality, why'd you be shooting at 1600 with a 5.6x compact in any case? That's 50k on a FF. Frankly, if that's where you are, stick it in 'Party' scene mode, snap and see what you get.

If you don't take the ISO into consideration when choosing the f-stop and shutter speed, then you don't know how high the noise will be in the final image, because it's the ISO that tells you how high the exposure (strict definition!) actually is with the chosen f-stop and shutter speed.

Wrong. What tells you how high the exposure is, is measuring the exposure. Where you're getting confused is that the modern camera UI makes you measure the exposure in terms of ISO, rather than any other unit. But all that means is that you're measuring the exposure in ISO units. If your meter was calibrated in lux seconds, it would do quite as well.

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Bob

Sure, but we'll have to settle for the units that our cameras use.

You, but you're still just using it as an exposure meter. And if you got a phone, you don't even have to do that.

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Bob

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