ISO vs. Shutter Speed

<p>I still am very confused over the selection of shutter speed and ISO. I see the following situation a lot. In Wed. Picks there<br>

is a photo of 2 musicians in b/w. It appears to be a daylight shot. The ISO is set to 800 and the shutter speed is set at 1/800<br>

sec. The photo was taken with a 70-200mm 2.8 lens.</p>

<p> My question is what is the advantage of such a high ISO in combination with such a high shutter speed? It has been<br>

suggested to me that under most circumstances the lowest ISO is recommended to obtain the least noise. Would the shot<br>

mentioned have better results with for example, ISO set at 200 and the shutter speed set to 1/250 sec.? As always, thanks<br>

in advance.<br>

Joe</p>

<p>Hi Joe. I would guess one of:<br />

<br />

a) The photographer wanted a deliberately grainy look, or<br />

b) The camera was set up to capture fast action (which, admittedly, there doesn't appear to be in this shot - assuming you mean the first of this week's) and the settings were an accident, or<br />

c) It just didn't matter - ISO 800 is reasonably low noise on modern bodies, so maybe the camera was set to ISO 800 knowing it would be "okay" (with the expectation that photos would be taken in low light during the same session), and used in aperture priority.<br />

<br />

At ISO 200 there would be slightly less noise/better sharpness (depending on the noise reduction) if the only motion to be worried about was normal camera shake, but - especially at the size presented - whether you'd notice the difference is another matter. Maybe something <i>was</i> moving fast enough to justify a 1/800s shutter speed - if the photographer was in a moving car, the settings worked very nicely!</p>

<p>My guess is the photographer wanted shallow dof to emphasis the hand by isolation. </p>

<p>Leslie - it's not taken at full aperture, but I think the question mark is more about the very high shutter speed than the choice of aperture. I'd not read too much into it (and I like the image).</p>

<p>ISO versus Shutter Speed? I didn't know it was a fight, but my money's on Shutter Speed - he's fast!</p>

<p>Seriously; it's not a competition and there's no contradiction in having a high ISO and a high shutter speed. If you need a fast shutter speed as well as some depth-of-field and the light's not bright enough, then all you can do is raise the ISO. Besides, modern cameras like the D700 can give you an ISO of 1600 or 3200 with almost no visible noise. So ISO becomes just another control in your armoury; and if it wasn't meant to be changed there wouldn't be a button for it, would there?</p>

<p>Here's the photograph in question:<br /><img src="http://static.photo.net/attachments/bboard/00Y/00Yool-364557584.jpg" alt="" width="466" height="700" /><br /><br />The photographer in question (me!) had just been shooting a bunch of people under a very shady tree canopy, and needed enough DoF to get several faces in focus. That called for a high enough ISO to shoot at f/8 while still having a tolerable shutter speed to freeze subject motion (in those conditions, I got 1/250th or so as long as I was at ISO 800). Done with that, I turned around to get a few quick shots of the swing band playing nearby, and liked the look of the stand-up bass's sculptural headpiece, the player's watch, etc, with the sax man out in front of him ... but I didn't like the very busy background, which would have completely swallowed up those details.<br /><br />So, to control depth of field and isolate the bass player's instrument and hand, I opened the lens up to nearly its widest aperture, and used it at f/3.2. I don't mind doing that with Nikon's 70-200/2.8, because its bokeh characteristics, even with all of that bright, contrasty stuff going on, are something I know and like well enough.<br /><br />But because I don't usually like auto ISO and was working quickly, the camera stayed at ISO 800 - and no harm done with a D300 as long as things aren't underexposed. And, as a result, and because I almost always shoot in aperture priority mode, the camera's metering system pushed the shutter speed up to 1/800th in that slightly brighter light - which suited me fine, since that bass player was moving the neck of his instrument around like Fred Astaire dancing with a hat stand, and I really wanted to preserve the details of the scratches, the tuning hardware and the rest, with no motion blur.</p>

<p>I've shot some very use-able stuff accidentally on ISO 1600, even on my old D50.</p>

<p>Nice shot... who cares how you got it...</p>

<p>Matt,<br>

Very nice photo and a good explanation. I'm just starting to use my D700 more, and I'll try some higher ISO options.<br>

I'm also a bass player (not a musician, just a player), but I always take my watch off when playing, thinking it will make me "faster." Not likely.</p>

<p>Depends on what you are after. I often shoot at night, and my subjects move fast. I need a fast shutter speed and the only way to get that is to use high ISO (and wide aperture.) I typically shoot at ISO 400 in bright daytime, and ISO 800 most other times. I usually am after fast shutter speeds with some DoF.<br>

Kent in SD</p>

<p>Thanks, Matt - mystery solved! (And, again, nice image.)<br />

<br />

In case this information helps anyone: up until very recently I used my D700 mostly in aperture priority, with auto-ISO set to keep the shutter speed above 1/focal length. Due to the inconvenience of changing the minimum shutter speed in the auto-ISO settings, with a zoom lens, I quite often ended up with a shutter speed appropriate for the long end of the zoom even when shooting at the short end - my 28-200mm often ended up at 1/200s even when used at 28mm, for example.<br />

<br />

It only recently occurred to me that I was actually better off shooting in manual mode with auto-ISO enabled; that meant I could tweak the shutter speed as the focal length of my zoom changed, just by rotating a dial. What I lose is the automatic change of shutter speed once I bump off the ends of my ISO range - but unless I have widely changing light conditions or am failing to pay attention to the in-finder meter reading, it's usually more useful for me, and means I'm not wasting my ISO whenever I use a zoom lens. I'd use auto-ISO less if there was a convenient way to set ISO explicitly one-handed.<br />

<br />

I've spent all day with an Eos 300D accidentally at ISO 800 - and you can <i>see</i> ISO 800 on a 300D. But then I also spent a whole evening on astronomy exposures without realising the camera wasn't producing raw images. And I've taken quite a lot of photos without realising the camera was in manual focus mode, as well...</p>

<p>Matt,</p>

<p> As a novice, I appreciated your explanation. In no way was I objecting to your technique, just trying to learn.<br>

The comment from another photographer... "Nice shot... who cares how you got it", kind of rubbed me the wrong<br>

way. I really do care how you got it. <br>

Thanks,</p>

<p> Joe</p>

<p>It's funny, and not to get off subject but when I read the OP the first thing I thought of was "well, if it was a D300 the shooter probably realizes ISO800 is better than ISO400". Because my D300 is certainly that way. especially if there is red in the picture. So I see from Matt's explanation that it was the D300, just not for the reason I was thinking. I shoot sports more than anything and on a day where it's overcast and I need higher ISO than 200 I jump right over 400 and go right to 800 because it really does look a lot better.</p>

<blockquote>

<p>Would the shot mentioned have better results with for example, ISO set at 200 and the shutter speed set to 1/250 sec.?</p>

</blockquote>

<p>that combo probably would have worked just fine, but as matt's shot shows, the d300 handles ISO 800 pretty well. the other question is, would the shot have worked at f/8? not really, as matt explains.</p>

 

<blockquote>

<p>It only recently occurred to me that I was actually better off shooting in manual mode with auto-ISO enabled.</p>

</blockquote>

<p>i found this out pretty quickly when shooting live concerts. the lighting changes frequently, and dialing in ISO in-between every shot can hamper workflow, even with a D300 or d300s, which have top-left direct buttons (it's a bit easier on a D3/D3s, due to the lower-left ISO button, which is easier to locate with the camera in shooting position. also, the d3s goes to crazy-high ISOs so i prefer to dial in a direct value.). so if you set auto-ISO that leaves you with two settings you control: shutter and aperture. if you know where you want to be with those two, on recent cameras, you don't have to worry about ISO being too high as long as you don't go over whatever is an acceptable limit for you. the downside of auto-ISO is it can choose a higher value than what you could have got away with. but if it means the difference between missing a shot because you were tweaking settings and not missing a shot, i'd go with the latter.</p>

<p>btw--nice shot, matt!</p>

<p> </p>

<p>Hey, Joe - no worries! I didn't take it as anything but curiosity, and I'm glad you found it interesting. I care how I get 'em, too - and the more I do it, and think about things like what I described above, the more second nature it is to work through that stuff on the fly as things are happening in front of you.</p>

<p>Eric - just to clarify, I'd been using auto-ISO from very early on, having established that the default position of the ISO button on a D700 was spectacularly inconvenient if your left hand is a foot in front of the camera holding a long lens. I'd failed to register that the D3 has an ISO button in a (slighly) better position; <i>why</i> you can't set it with one of the programmable buttons I don't know.<br />

<br />

The thing I only recently realised is that I'm better off using manual (+ auto-ISO) than using aperture priority with the auto-ISO setting a minimum shutter speed. The latter is effectively what I want, but since there's no way to tweak the shutter speed limit without significant faffing around in the menu, I always ended up with a faster one than necessary. Aperture priority would still be the right option if I'm shooting in decent light at minimum ISO, but I spend so much time indoors with auto-ISO enabled anyway, I'm better off using manual mode so I can tweak the shutter speed quickly as I zoom, and paying attention to the rare occasions when I'm hitting ISO 200. It's possible that I'm the only one who hadn't realised this from the get-go.<br />

<br />

As you say, recent cameras, especially full frame ones, have made auto-ISO useful. I never missed it on my Eos 300D because you'd only ever leave ISO 100 if you had no other option. I'm not too worried if I hit ISO 6400 on my D700.</p>

<blockquote>

<p>I'm not too worried if I hit ISO 6400 on my D700.</p>

</blockquote>

<p>i see what you mean, however, i don't like to use 6400 if 2000 will suffice. with the D3s, there's a tendency to rely on the camera's insane low-light ability, rather than use high-ISO in situations where it is warranted and not when it isn't. i've discovered the camera is pretty good at base ISO w/flash too. and normally, i don't have to go super-duper high, except in situations where i need a certain shutter or aperture, like say, f/4 and 1/200 in a dimly-lit tent. it's less noisy to use a 1.4 aperture lens than boost ISO just because you can, and contrary to popular belief, the D3s isn't noise-free, it just handles it very well in the upper register.i do find the button placement helpful, especially when switching between a flash and available light shot. with the d300s, i always have to look at the button to make sure i have the right one which means moving the eye away from the viewfinder. that's just one of those subtle things that makes up for the price differential.</p>

<div></div>

<p>In reading through this a couple of thoughts came to mind. </p>

<p>- I've been around here for several years now, and I think this thread is a great example of how this site can help someone better understand certain aspects of photography.</p>

<p>- After reading about how you change ISO on the D300S and D3S, I really like the feature on my D7000 that lets me directly control ISO from the rear control dial (without having to push any buttons), while being able to adjust Aperture from the front dial. I pretty much always shoot in Aperture Priority, and not having to use 2 hands to adjust ISO is great, since I've generally got my left hand holding a heavy lens. I've set my Pentax up the same way, even those lenses weigh less than the lens caps for my Nikons. Can you not set up the D300S or D3S that way?</p>

 

<p>Eric: Oh, I agree, and that's why I'm pleased to have worked out how to change my shutter speed/auto-ISO balance quickly when using a zoom lens. But on a D700 (slightly less so D7000, slightly more so D3s) ISO 6400 is usually a usable, if not ideal, setting; on my 300D, as on colour film, you're very lucky to get anything useful at ISO 1600. Modern cameras make the difference between a slightly noisy picture and no image at all. And my problem with the ISO button placement on the D700 isn't so much that I can't see it as that, with a long lens, the only way to get at it is to balance the lens precariously in my left hand and hop my right hand over the top of the camera, hoping not to drop everything. Even then, I need press-then-rotate controls rather than (as I prefer) rotate-while-pressing. Short of sitting down and resting the lens on my knee, there's no way to put my left hand on the ISO button and the right hand on the control wheels.<br />

<br />

Frank: Well, I'll be danged - Nikon either came to the same conclusion as me, or my ranting here for the last couple of years got noticed. :-) I'd utterly failed to notice option (ironically) d3 on the D7000. I've not checked the D3s/D300s updates, but glancing at the D3/D300/D700 manuals, there's definitely no such thing as "easy ISO" - you <i>have</i> to use the ISO button (and no other button is a substitute). This might be a big reason for me to start saving up for a D800 - although not so much as if someone lets me hack <i>everything</i> I want into the BIOS...</p>

<p>I don't know, but personally, when I'm out to take certain pictures, especially black and white ones, I deliberately set a high ISO. I just don't find the perfection of ISO 100 very appealing... and I am serious when I say that. That way, I get what almost looks like grain, and at the same time, it gives me the possibility of the higher shutter speeds I prefer for handheld street shots. I almost never shoot in aperture priority, but of course, I do keep an eye on it.</p>