Manual vs. Aperture Priority mode

[LungFish]

Whatever effect you're trying to achieve with auto-iso, i wouldn't trust the camera to achieve it. The only time the camera can think properly is when there is only one possible answer.

I don't like your example anyway because it sounds like a job for flash.

 

[ralphh]

*sigh*

ok, on your D5000, on the auto-iso menu, you can set a minimum shutter speed, as well as max iso.

So you can say "never set the shutter below 1/60th" and it won't. The 5D2 doesn't have this (5D3 does tho) and it's a pain to go back to a camera that doesn't have it. That's the only point I was making.

Sheesh, I can't believe I'm getting flamed for thinking that a feature that pretty much every camera has these days is good idea.


As for using flash, it's not unreasonable to use a fast prime wide open, then want to close down a little and need to bump up the ISO a stop but not attach a flash, but not want to be shooting there all the time if it's not needed.

 

[TCampbell]

Ha, guess Canon weren't just sat on their @rses for 4 years between the mk2 and mk3

Actually, you should be fine with ISO 6400 on your 5D Mk II.

This was shot with a 5D II at ISO 6400:


Chris Koza in Concert by Tim Campbell1, on Flickr

Is there noise in it? Yes... the next image over in the Flickr "set" is a 100% crop on his face (from the same photo as this one) and at that resolution you can definitely see the noise. At web resolutions the noise is still pretty tame. At ISO 800 you should have great difficulty detecting noise in your images.

Note this is because you own a 5D II. I can think of lots of cameras that would have obvious noise levels at ISO 800. Most newer cameras don't have a problem. Older cameras will struggle. I was just reading a review of the Pentax K-30 in an issue of Pop Photo on a plane flight and was pretty surprised to see that ISO 800 is pretty much as high as it gets. Any ISO above that was rated "unacceptable" by the reviewers. In comparison, they gave the 5D III the same moderate score at ISO 25,600 and it didn't become "unacceptable" until 51,200.

Meanwhile back to the original discussion...

When I approach any shot, what I WANT is the luxury of using any ISO, any aperture, or any shutter speed. That's what I want ... but I don't always get what I want.

Here's my thought process & preference for what modes I use and why.

1) If I'm not shooting action and I have plenty of light, my preference is to use aperture priority mode (Nikon "A", Canon "Av"). That's because I now have the luxury of controlling the depth of field to anything I want. I'm not so much thinking of this as setting the aperture just arbitrarily... I'm setting it for depth of field purposes. The "plenty of light" stipulation I mentioned says that I don't have to worry about shutter speeds that are too slow for a hand-held shot (BTW, mini-rant here... I am NOT averse to carrying a tripod around... something I do quite often. As a photographer, be willing to do what you need to do to get the shot right. No being lazy about hauling gear or walking to the right location, etc. and then blaming the camera or conditions later. If it was _possible_ to get the shot by any means, and you didn't get the shot, then that's _your_ fault. Not the equipment. The equipment is, for the most part, not allowed to vote on how you take the shot. You make the decisions... you take the responsibility. )

2) If I am shooting action, then I don't necessarily have the luxury of shooting at any speed. Now we've got a minimum shutter speed limit. I switch to shutter speed priority (Nikon "S", Canon "Tv") and set the speed to whatever it needs to be... whether I'm trying to create deliberate motion blur or freeze action.

3) If I don't trust the light meter (high key and low key shots are good examples) then I pull out the incident light meter and find out how much light I _really_ have. I have two of them... a small compact incident meter, and a larger full-function meter.

There are lots of nuances to this. At event photography I often use aperture priority but set an exposure compensation bias. There's a lot of low-key conditions. The camera wouldn't naturally get the exposure right, but since I know that it'll probably consistently over-expose by about 1-1/3rd stops, I can just dial in the compensation rather than follow rule #3. This is especially important since, at a concert, the lights are often varying rapidly and I'd _never_ keep up with the rapidly changing conditions if trying to shoot entirely in manual mode.

Most of the time, I use Av on my camera.

 

[ralphh]

What I want is the luxury of jus t picking an apeture and forgetting the rest because I set my shutter speed once, on the auto-iso menu, not every shot. Because that's what I've been used to recenly. I'm happy to set it as needed, but sometimes I forget and it's annoying. End of story.

If you bought an old manual exposure camera and occationally forgot to set the shutter speed because you're used to apeture priority, you might say "wow, didn't realise how good semi-auto was, sometimes I forget to set shutter speed when I'm mid-flow, and it's annoying that I do that".

Same thing here. I'm fully understand how exposure, and the camera works. I just sometimes forget that it's less automated on the 5D2 than on the cameras I've owned for the last 4 years.

What makes it doubly annoying that it's lens length speciffic - the 5D auto iso works fine for long lenses, but pooly for wide ones for shooting portraits. I don't own a zoom luckily - it'd be even worse with zooms; if you have a 24-70, you'll get sharp shots at 70mm, but zoom out and you'd get blurry ones at 24mm.

It's tripply annoying because it's exactly the same as (or better than) the cameras I owned for 6 years before that, so it shouldn't be as hard as it is to get back into the habbit of keeping an eye on shutter speed again as it is.


Ironically, when this started, I said I was considderig going full Manual mode (which I am perfectly comfortable using), just to help be get back into the mindset of keeping an eye on shutter speed, and now I'm being told I shouldn't let the camera pick things for me by people who are using Apeture priority :waiting:


For those not using Auto-ISO on a more modern camera, I suggest you try it - you can set minimum acceptable shutter speed, max ISO, and then the camera will either use 1/focal length, or your minimum shutter speed, which ever is greater. Some have even more options. You'll always get sharp results if you've set you minimum shutter speed correctly, and you'll always be using the minimum ISO you need to get it.

 

[TCampbell]

What I want is the luxury of just picking an apeture and forgetting the rest because I set my shutter speed once, on the auto-iso menu, not every shot. Because that's what I've been used to recenly. I'm happy to set it as needed, but sometimes I forget and it's annoying. End of story.

If you bought an old manual exposure camera and occationally forgot to set the shutter speed because you're used to apeture priority, you might say "wow, didn't realise how good semi-auto was, sometimes I forget to set shutter speed when I'm mid-flow, and it's annoying that I do that".

Same thing here. I'm fully understand how exposure, and the camera works. I just sometimes forget that it's less automated on the 5D2 than on the cameras I've owned for the last 4 years.

What makes it doubly annoying that it's lens length speciffic - the 5D auto iso works fine for long lenses, but pooly for wide ones for shooting portraits. I don't own a zoom luckily - it'd be even worse with zooms; if you have a 24-70, you'll get sharp shots at 70mm, but zoom out and you'd get blurry ones at 24mm.

It's tripply annoying because it's exactly the same as (or better than) the cameras I owned for 6 years before that, so it shouldn't be as hard as it is to get back into the habbit of keeping an eye on shutter speed again as it is.


Ironically, when this started, I said I was considderig going full Manual mode (which I am perfectly comfortable using), just to help be get back into the mindset of keeping an eye on shutter speed, and now I'm being told I shouldn't let the camera pick things for me by people who are using Apeture priority :waiting:

I don't believe it was anyone's intent to "flame" you (perhaps I'm wrong).

I am concerned about a couple of points you mentioned above.

You mentioned that ISO and auto-ISO are lens focal-length specific. That's not true. Exposure is exposure. The lens has nothing to do with it. If you use an incident light meter and it says you can take a shot at ISO 400, f/4, and 1/125th of a second... then you can take that shot using that exposure with ANY CAMERA and ANY LENS as long as the camera and lens can accommodate those settings (the light meter has no idea what camera and lens you own.) If I take off my 24-70mm lens and attach my 70-200mm lens, the exposure choices available to me don't change (in my case both lenses can provide f/2.8). Only the focal length choices change. Since focal lengths affect the depth of field, the depth of field changes as well.

Long focal length lenses are generally preferred for portraits because they do several flattering things... (a) they don't create wide-angle distortion and (b) the compression effect on the lens also compresses the depth of field which makes it easier to get a pleasantly blurred background when using a long focal length lens.

If you're getting sharp focus at 70mm you should definitely not get soft focus at 24mm. That's because the wide-angle focal length stretches the depth of field. Anything that could be in focus at 70mm also be in focus at 24mm... and in fact quite a bit more will be in focus. It's harder to create a deliberately blurred background at 24mm. The lower the focal ratio, the greater the depth of field. I have a 14mm f/2.8 prime. It's pretty much impossible to get a pleasantly blurred background with that lens no matter what you do. In fact the depth of field is so generous that you can pretty much just dial the focus ring to 3' and forget it for the rest of the day... everything will probably be in acceptable focus (or at least very close to it.)

I don't believe anyone took issue with you preferring to use the Av mode. I use the Av mode myself.

Where I think you ran into opposition was when you said that if you used Av and changed your aperture down by a stop then you'd need to remember to go set your ISO up by a stop to compensate. The whole point of the semi-auto modes is that you set one thing and the camera does the rest for you.

You later described that if you did not do this, then you'd end up with unacceptably slow shutter speeds for hand-held photography. We would suggest that if you are shooting subjects that don't sit still and require a fast enough shutter speed, then perhaps you should consider shooting in shutter speed priority mode.

If you set auto-ISO and have a low-focal ratio lens, and use shutter priority mode (Tv) then the computer will use the shutter speed you require, and it will first go for a low focal ratio and THEN start boosting ISO (automatically). In other words... the camera will do exactly what you want and have been doing in Av mode... except you mentioned you are frustrated with having to remember to keep an eye on the shutter speed and ISO when in Av mode. The 5D II avoids going over ISO 3200 when in "auto ISO" mode (even though you can manually set a higher ISO.) On many cameras you can set the auto-ISO limit. I can do this on my 5D III. I cannot do this on my 5D II.

The 5D II body is designed to let you do everything without taking your eye away from the viewfinder. Make sure the on-off switch is in the position that points to the rear selection dial (so the dial is enabled). In manual mode you can control the shutter with your index finger, the aperture with your thumb, and remember that the ISO is on the top of the camera next to the LCD backlight button (it's the right-most button out of the three large buttons on top.. the backlight button is to the right but it's a tiny button. On the 5D III those buttons all have flat tops except for the ISO button, which has a dimple sticking up (like the F and J keys on a typewriter keyboard) so that you can find the button without even looking. On a 5D II you have to remember which button it is, but with practice it becomes automatic to find it.

So the bottom line is: We agree... that would be frustrating. But I think you may find there's a mode to do what you want. Try shooting in Tv mode and see if it doesn't get you the results you are looking for with less fuss than you are currently experiencing.

 

[ralphh]

Really, none of that answers any of it, so i'll try and break it out one last time... after that i give up this really wasn't worth this much discussion

When i say auto iso is lens speciffic, what i mean is it will aim for 1/local length.. So for a 200mm lens it'll pick 1/200 and for a 30mm lens it'll pick 1/30

This is designed to prevent camera shake.

The trouble with that is it doesn't necessarily stop subject movement; you generally need around 1/60 for a portrait - it depends on
your subject and how still they can sit - kids more, adults less normally.. A similarly framed shot at 35mm is just as prone to subject movement as a 200mm.

So with auto iso, if you put on a 200mm lens you'll get a shutter speed that can freeze your subject, if you put on a 35mm one, you wont.

Camera manufacturers know this and have added the minimum shutter speed option. Nikon about 4 years before canon, at least on the higher end models.

Regardless of whether you use Tv or Av you'll need to adjust your iso up from base to keep the shutter speed above 1/60th (for example) when taking a portrait if light is lower than the point where every aperture you want to use gives you a good shutter speed at base iso, and you can either change your iso a lot so you're always using the lowest iso you can get away with, or go with the approach of set it high enoug to cover the apertures you want to use and leave it there. I prefer to change it. What i prefer more is to be able to set a minimum shutter speed and have the camera change it.

Wasn't asking for help, just saying it's frustrating taking a step back in terms of camera automation and not being able to remember to do something i used to do without thinking about. It's amazing how dependent you get on these aids. If i went back to a film camera now my head would probably implode. Or i'd actually do me some good lol.

I'm certainly not going to shoot Tv and decide not to go below a certain shutter speed as that limits my aperture options - i do actually care what my aperture is beyond the effect it has on exposure. Any anyway, I'm so set in my ways with how I shoot after 15 years on Av, i'd just be looking at the aperture change as i turned the dial, regardless of whether the camera was in Av or Tv :lmao:

I should have gone straight from 1Dmk2 to 5Dmk2, without a trip over to D700 in the middle - damn nikon and their well thought-out firmware!!

One day when the 5D3 is a reasonable price second hand this issue will go away again lol

Part of the problem is region and season specific - I'm needing to use iso 1600 at f2.8 in the middle of the afternoon indoors at this time of year in England - even right next to a south facing window if i hop up to f5.6 i need iso 6400, but i don't want to leave it there when i go back to f2.8.

 

[EIngerson]

Well, I give up.