Xpatch Loc: New York, Antigua, GT.

Ifi set the flash output manually i try to, I think auto iso may affect it but i will have to try i usually set my iso at 400 and decide to use shutter speed or f stop to get the final combination as not to advanced but it’s Ok.

selmslie Loc: Fernandina Beach, FL, USA

I understand what you are saying but there is a fundamental difference.

You need to use EC to control the ISO. Most cameras make it easier to change the EC than to change the ISO directly. But you are still relying on the camera's meter to complete the relationship between aperture, ISO, shutter speed and light value (LV).

LV is the actual determinant of whether the JPEG looks right and if the raw file records useful values.

The fundamental problem with reflected light reading is that it tries to derive the LV from the light being reflected back to the camera, not the light actually striking the subject.

For example, direct sunlight shining on a scene that is predominantly dark, gray or light (reflectance) will try to make all of them look gray. Is that what you want? Of course not so you have to take a SWAG at how much EC will render the scenes correctly.

By using Sunny 16, an incident light meter or a simple table of LV assumptions you can cut out the guesswork around determining EC or ISO.

Pixeldawg Loc: Suzhou, China

Hmmmm... on here, your shots are underexposed. I'd say your technique is suspect and the post work as well. I take my students for a "photo walk" third week of class, and we actually disprove this technique. If you don't believe me, walk around a large pillar and take about 4 different light readings and you're going to see that they are not all the same. Angle, reflectivity, light intensity all play into the final exposure and if it was as cookie-cutter as you're implying, you wouldn't need all of the options for exposure that you're given on your camera.

BebuLamar

If you put it that way I can say in P mode it's manual too. I can make the camera to assume any settings I want in P mode. Using EC, AE-Lock and P shift controls.

selmslie Loc: Fernandina Beach, FL, USA

Where is "here"? This thread, this site?

You haven't looked at many of my images. I suggest that you take a look at my web site. All of my car show images taken in full sun were exposed at LV 15.

You should also look at Highlight warnings - the rest of the story where each image was exposed at LV 15 regardless of which direction I was facing.

Overexposure with blown highlights can't be fixed.

But don't disparage underexposure. It's easy to correct with today's wide DR cameras so long as you stay close to base ISO. Even in broad daylight you can miss the exposure by +/- a full stop and recover a great image. Take a look at https://www.uglyhedgehog.com/t-659116-14.html#11474138 and https://www.uglyhedgehog.com/t-659116-14.html#11473400

R.G. Loc: Scotland

What I'm saying is nothing like as complicated as what you're making it out to be. I use the EC control to control EC (as required), I use the aperture control to control aperture and I use the shutter speed wheel to play off ISO against shutter speed.

The main implication of that last point is that I'm seeing ISO as the most compromisable variable and shutter speed as the second most compromisable variable (for landscape), so if the need for compromise arises I can address it firstly with the shutter speed/ISO control, and if that isn't sufficient I can re-adjust aperture.

Using the EC control to deliberately under-expose is an option in tight circumstances, but I don't see any advantage in doing that as opposed to letting ISO go high.

SuperflyTNT Loc: Manassas VA

As opposed to your website of mediocrity?

selmslie Loc: Fernandina Beach, FL, USA

You are correct that it's not that complicated. As I said in my post on latitude, if you plan to develop from raw you can be off +/- one stop and it would not matter. It's only important if you want the image SOOC to be just right or if you want to avoid blowing the highlights.

But it really a question of priorities. That's why two of the options are Aperture priority and Shutter or Time priority. You need to pick the most important one first, give it priority.

Those of us who are shooting film tend to think of ISO priority because we feel that noise, grain and DR are the most important considerations.

Anyone who shoots Manual+Auto ISO gives ISO the lowest priority. When they do so they should not be surprised by the consequences.

R.G. Loc: Scotland

Compared to letting ISO go too high, letting shutter speed go too slow or letting aperture go too wide are far more likely to have uncorrectable consequences. We have aperture priority and shutter priority - why do we not have ISO priority? And why do most cameras have a wheel for direct control of shutter speed and (when they have it) another wheel for direct control of aperture, but no direct control of ISO?

ASA or ISO may have had a major significance with film, but digital cameras are moving towards ISO indifference.

selmslie Loc: Fernandina Beach, FL, USA

We always had ISO priority, we just never called it that. It's just that the word "priority" was not applied until we had auto exposure. And my Df has a wheel to set the ISO directly. Simpler amateur cameras just don't make it as easy to change.

We still have ISO priority. It's whenever we are not using Auto ISO which was the last of the autos to show up.

But a deviation of one stop for any one of the three variables actually has minimal effect with digital when you are capturing raw daylight images near base ISO. For example:

ISO - the difference between ISO 100, 200 and 400 is virtually impossible to see.
Speed - The difference between 1/500, 1/1000 or 1/2000 is almost impossible to detect.
Aperture - The difference is DOF between f/5.6, f/8 and f/11 can be calculated but otherwise virtually impossible to detect in a real image, even at 100%.

Someone might go to extremes to demonstrate the difference, which is real, in a lab environment. But it cannot be reliably measured in a real image.

There is no such thing as ISO indifference. If you are thinking of ISO invariance that's a totally different concept and it has nothing to do with what we are discussing here.

R.G. Loc: Scotland

ISO is becoming less and less significant. I'm not suggesting that ISO will become irrelevant, but the upper limit of usable ISOs is rising. The effect on dynamic range isn't going to go away, but the point I was making is that ISO is becoming less critical. In the post that I was responding to, you were implying that Auto ISO was a liability, and I was suggesting that ISO is one of the lesser liabilities and it will continue to be less and less of a liability.

bleirer

Canons, at least mirrorless, have the equivalent of ISO priority. They don't call it that, though. I imagine every brand has a way to do it. Setting the lens control ring or multifunction button to iso while in program mode, for example.

SuperflyTNT Loc: Manassas VA

Essentially most cameras that offer the ability to control aperture, shutter speed and ISO also offer different combinations. If you shoot aperture priority you generally also set ISO, so in essence it’s aperture AND ISO priority. The same with shutter priority You can also shoot those modes with auto ISO. So really shooting in auto or Program mode with a fixed ISO could be called ISO priority.

donspang

This thread has gone NUTS. A lot of wrong info . Given the correct exposure the only thing that effects noise is ISO. Shutter speed and F stop do NOT effect noise unless you are using outo ISO. period

donspang

Given the correct exposure ( f stop and shutter speed) the ONLY thing that effects noise is ISO. period! Shutter speed and F stop do NOT effect noise unless you are using auto ISO
donspang