jerrypoller Loc: Huntington, NY

I am a enthusiastic amateur who's been reading this forum and working on my skills for the past year. My setup yesterday was a Nikon D610 with a Nikon 35-70 f/2.8 lens in manual mode with auto ISO - it's become my default lens unless I need a wide angle (Nikon 20-35 f/2.8) or sports zoom (Nikon 80-200 f/2.8). I was photographing several of my grandchildren outdoors yesterday evening. I usually set the aperture to f/2.8 or f/3.3 to keep the [auto] ISO as low as possible for maximum sharpness (e.g. minimum grain/noise). Yesterday, they were posed/stationary - a rarity - so I could set the shutter speed at 125th, the focal length at 70mm, and the aperture at 5.6 - the camera selected the ISO at 450.

I should have known better from all the comments from more experienced UHHers, but I was still very pleasantly surprised by how much sharper the photos were at f/5.6 than at f/2.8. Obviously, the depth of field kept everyone in perfect focus, and I guess f/5.6 is at/near the sweet spot for my lens. Needless to say, I will be using the smaller apertures whenever possible from now on when the light allows reasonably low ISO settings and relatively slow shutter speeds (at least 2X the focal length of the lens).

Long way of saying I'm working on understanding the exposure triangle better and learn something new each time I take my camera out or read another post.

rook2c4 Loc: Philadelphia, PA USA

Why not take the camera off auto ISO, and instead simply select a reasonable ISO value yourself? I think that would make things less complicated, as you then won't be forced to select an aperture value specifically to manipulate the behavior of the auto ISO function.

CaptainC Loc: Colorado, south of Denver

You evidently have a film mentality. With your camera, an ISO of 400 or even 800 will be fine and 1200 or 1600, while it will show some noise, will be perfectly usable.

But I certainly agree with rook2c4 that the selection of Auto ISO for this purpose may not be the best approach. It is not a BAD approach - just not needed.

Apaflo Loc: Anchorage, Alaska

Experience is a great teacher! It's one thing to read about it, but what it really means becomes so much more clear about the time that a dose of reality slaps us in the face! Then the little nuances that actually were mentioned but didn't seem so important all of a sudden fit right into the perspective!

Exposure is time and intensity. The shutter speed sets time and the aperture sets intensity. ISO does not change exposure, but it does adjust brightness of the recorded data for whatever exposure was selected. Thus the triangle.

With a full frame sensor and 24 MP the sharpest aperture on most lenses is from f/5.6 to f/8. Higher than that begins to see the effects of diffraction, and lower shows effects of lens design and manufacturing aberrations.

Since your monitor, or a print, can only display maybe 6 or so fstops of dynamic range if you expose very carefully to get at least 6 fstops of dynamic range, and set the black level for exactly that... all images appear to have no noise! (The devil is in the details, because if the shot is underexposed and/or has to be pulled up by a couple f/stops for any reason, there will be copious noise.)

Your D610 provides 6 f/stops of dynamic range at ISO's up to about 6400. If you can nail exposure there won't be noise. If you shoot at ISO 1600 though, you have 2 f/stops to play with. At ISO 800 there are 3 f/stops of "slop factor"! It isn't just missed exposure, but compensation for excess dynamic range in the scene that you want to be visible in the photograph, that can make use of that 3 f/stops. So do take ISO into account, or at least the eventual processing that will be done with the RAW data, when setting exposure. It's just a lot easier to process a low ISO RAW file.

I absolutely agree with using AutoISO and manually setting exposure for artistic effect. Also turn on the display of blinking highlight alerts and the RGB histogram. Make sure you push exposures right up to where highlights are at the maximum. For shooting in JPEG don't allow blowing out the highlights, but if shooting RAW it is safe to let almost every shot have something blinking. Pick apertures for DOF, and if possible stay close to f/5.6 or f/8. Pick shutter speed to stop or blur motion as desired.

Let the ISO fall where it may, because within a fairly wide range it won't make any difference as long as the exposure is correct.

jerrypoller Loc: Huntington, NY

I've tried shooting in A, P, and S modes, but found M most satisfying. I usually have a shutter speed in mind to catch action, and a depth of field need to keep everyone/thing in focus, so I let the camera select the lowest ISO that corresponds with my S/A settings. Using the built in exposure meter tells me whether I have to compromise either my A or S to regulate the ISO. It seems to work best for me since I can, if necessary command all three elements per the exposure meter (although I sometimes get a "perfect" exposure on the meter and then the picture isn't exposed properly). As I said in my post, it's a learning experience. Glad I have this forum to help educate me.

imagemeister Loc: mid east Florida

f5.6 not only allows better IQ from the lens, but it also covers up any focusing errors - in relation to f2.8

Apaflo Loc: Anchorage, Alaska

That is very well stated!

One thing that hasn't been mentioned, though from what you've said I'm sure you must be using with regularity, is Exposure Compensation.

With Manual Exposure mode and Auto ISO enabled, EC becomes the adjustment mechanism for the "ISO leg" of the Exposure Triangle. Adjusting EC doesn't change exposure (because that is in Manual mode) but directly causes the ISO to be biased up or down to make the recorded image brighter or darker. Generally, all things being equal, if the right edge of the histogram (or the blinking highlight alert) is not in the desired place, Exposure Compensation is the knob to twist first.

jerrypoller Loc: Huntington, NY

THANK YOU, THANK YOU. This is why I keep coming back to this forum - I become a better photographer by listening to you.

Actually, I hadn't been using EC because I had read/been told that it doesn't work in M mode. I never made the connection between its affect on ISO. So, I just took three shots - all at 125 and f/5.6. The non-EC shot had just a smidgen of blinking highlight at ISO320. Then I shot one with +2 EC, which blew out most of the white with ISO1250, and one with -2 EC, which was just uniformly darker (underexposed) at ISO 100.

New lesson learned - please keep them coming.

Apaflo Loc: Anchorage, Alaska

I'm glad I mentioned it!

Not all manufacturers do it right. Nikon does.

Exposure Compensation is nothing more than a way to "calibrate" the light meter. Dialing in +1 will require 1 EV more exposure because it makes the meter read 1 EV lower. Dial in -1 and it reads 1 EV higher. (It changes where "zero", for correct exposure, is.) And as a consequence, whatever the light meter controls is affected.

With Manual Exposure mode enabled, and Auto ISO off, all the light meter controls is the indicator showing under/over exposure. If P mode is on, it controls both aperture and shutter speed... and so on for other modes. With Auto ISO it controls ISO!

There is then the confusing factor of what gets changed first if all of those are enabled. ISO is at the bottom of the priority list. So if Aperture Priority mode is enabled, the meter controls the Shutter Speed first, and only when at the upper or lower limit for shutter speed will it change ISO.

There are some logical, but "unexpected" effects too. If you are shooting in manual ISO, with ISO set to say 3200, and then switch to Auto ISO, that 3200 becomes the default ISO for Auto ISO. With Aperture Priority enabled that means the shutter speed will be increased to maximum before the ISO is reduced. So you end up with a lot of shots at ISO 3200 and with very high shutter speeds rather than the reasonable shutter speeds and the nice low ISO that you might like and were expecting.

That is one very good reason to just use Manual Exposure mode, with Auto ISO, whenever it is reasonable. And always make sure to set the default ISO to a low value such as 100.

jerrypoller Loc: Huntington, NY

What I found (and still do I guess) was that when I dialed in a lot of + EC - say 4 or 5, the exposure "needle" would move to the left of the scale, indicating underexposure. The opposite would occur when I dial in lots of - EC - the meter would begin to show overexposure. It looked to me like it was doing just the opposite of what I was expecting. Then I was told that EC doesn't work with M mode, so I just figured the exposure meter was having heartburn since it wasn't expected to work under these settings. That's when I stopped using EC. Now that I'm aware of how it works, I should have far fewer under/over exposed images.

imagemeister Loc: mid east Florida

If you were using a Sony, you could see how it is working in the VF !

speters Loc: Grangeville/Idaho

Maybe you need to rethink a little bit your approach and consider first what DOF you would like in your picture. It doesn't matter what's in front of your camera, but to know what DOF is important to you, that's a good starting point and everything else just falls in place from there! I like to make another suggestion, get away from that hideous Auto ISO (that's just total crap in my opinion). That is one of the fundamental settings ( just like DOF), that should be set first, before thinking about anything else for an image!

jerrypoller Loc: Huntington, NY

Because I'm a novice photographer and a newbie here, I feel uncomfortable challenging a "regular here", but I'm not on the same page with you about your "hideous Auto ISO" comment. I'm thinking that DOF (keeping everything important in the photo in clear focus), and shutter speed (to freeze or intentionally blur the subject) trump ISO, inasmuch as today's cameras handle the noise(grain) so well. Unless your argument is that the camera's computer does a poor job of deciding what the appropriate ISO is for a given S/A combination, I don't understand your dislike for Auto ISO. I'm always open to correction though, if my logic is faulty.

Apaflo Loc: Anchorage, Alaska

Here are a couple thoughts to keep in mind...

Not all photographers of course shoot in the same style or have the same goals, and further we don't all have the same equipment.

A Studio Photographer certainly will have a different set of priorities than a Landscape Photographer, and even more different will be a Street Photographer. I tend toward the Street style, and that fit in fairly well with things you've said.

Camera's are another matter. A decade ago when the Nikon D2X came out I didn't see just a whole lot of use for Auto ISO. The darn camera could barely go above ISO 800 anyway! But one day a D3 showed up and eventually I rediscovered Auto ISO with great delight! And even more so with more recent cameras as the dynamic range became even higher.

But not everyone uses cameras with Sony sensors. There are lot of popular DSLR's that just don't have that kind of dynamic range. And without having experienced it many people just cannot imagine something that does them nothing of value might actually be very useful to others...

So let them rant. But take full advantage of your advanced equipment and you understanding of how it works.

jerrypoller Loc: Huntington, NY

You are a breath of fresh air here Apaflo. Sometimes I wonder if the "ranters" would be as ornery if they were giving their advice face to face, rather than through the www - somehow I doubt it. Anyway, like my golf swing, I want to improve it, not rebuild it - same thing with my photography skills. Thanks for your encouragement.