So the ISO will change to adjust the exposure, even in manual?
Is using Aperture priority bad?
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In Auto ISO yes. In 100% manual, no.
In Av mode, you set the ISO and the Aperture, and the shutter speed floats.
In Sv mode, you set the ISO and the shutter speed, and the aperture floats.
in Manual w/ auto ISO, you set the Aperture and Shutter speed, and the ISO floats.
Note: in the above 3 cases, the camera's metering system and exposure compensation sets the amount of light (or exposure).
In Manual, you set all 3.
Thanks for the advice on auto ISO. As stated earlier, I have never used it and did not understand how it works. Now that some of you have enlightened me, I will have to give it a try.
fcotterill
Well-known member
As we've both posted above, I'm in 100% agreement with @Butlerkid , Auto ISO works reliably with Manual.
It's one of the premium features made available in modern ILCs, particularly with ISO Invariant sensors that minimize noise.
The exposure is only changed by Aperture or Shutter Speed. ISO doesn't change the exposure. Increasing/Lowering the ISO only changes the sensor gain.
It's one of the premium features made available in modern ILCs, particularly with ISO Invariant sensors that minimize noise.
The exposure is only changed by Aperture or Shutter Speed. ISO doesn't change the exposure. Increasing/Lowering the ISO only changes the sensor gain.
Think of it as aperture and shutter priority.
As posted above, manual exposure with auto ISO is actually an automatic exposure mode but instead of aperture or shutter speed being the camera controlled floating parameter, ISO becomes the floating parameter though you can set high and low limits on ISO if desired.
After many years of shooting full manual or aperture priority I've gone to either manual with auto ISO or full manual for all of my shooting. To me manual with auto ISO is really powerful as I maintain direct control over the two most important creative settings (aperture and shutter speed) and within reason I'm fine if ISO floats up and down to achieve proper exposure taking into account any exposure comp I have dialed in.
Also small exposure errors in this mode just mean small ISO tweaks in post processing(via the Exposure slider) which with today's crop of largely ISO invariant cameras doesn't hurt image quality at all across most of the camera's ISO range relative to making the same adjustment at time of capture. In Aperture or Shutter Priority modes exposure errors will have altered either shutter speed (in aperture priority mode) or aperture (in shutter priority mode) and those can't be readily changed back in post processing the way you can when ISO is the floating parameter.
@Steve has a good blog post and video on shooting in this mode and why you might consider trying it out:
Manual Mode With Auto ISO - Backcountry Gallery
Did you know your Nikon camera has a “hidden” exposure mode? Sure, we’re all familiar with Program, Aperture Priority, Shutter Priority, and Manual – but there’s one that’s left off of the list – and that’s Manual Mode with Auto ISO. Basically, this setup allows you to adjust your F/stop and...
![backcountrygallery.com](https://backcountrygallery.com/manual-mode-with-auto-iso/\"/apple-touch-icon.png\"){kind=icon}
backcountrygallery.com
Replytoken
Well-known member
I guess the question I have is what metering mode the OP is using? Assuming its is a D500 body (as it was mentioned), the primary choices are Matrix metering, center-weighted metering and spot metering. Despite all of its amazing technology, I have found Matrix metering to be somewhat unpredictable in some situations, so I often use center-weighted as it is a bit more predictable, albeit less sophisticated. I suggest the Op switch between the two and seeing if the blown highlight issue changes one way or the other.
--Ken
--Ken
EricKlees
Well-known member
With my D500 and now with the Z9 i use full manual. I don't use the histogram in the EVF. I know the Nikon metering system so well i just use the meter in the VF/EVF instead. I just know in what scenes i needed to over or under expose. Late day low sun on eagles i may need to underexpose but as much as 2 full stops to protect the white feathers.
I suggest learning the meter and take note how to expose with it.
I suggest learning the meter and take note how to expose with it.
Old dog, new tricks
The whole thread started as a discussion on A mode vs auto ISO. Assumed you knew what's what
IMO auto ISO is the only auto exposure mode that makes any sense in this day and age. It is rather confusing that the camera companies still refer to it as "manual". I assume trying to avoid confusion during the transition from film but IMO creates more confusion. "Manual mode" isn't necessarily manual exposure. Must be some military minds involved.
Yes, this is what caused my confusion.
This is where the camera brands might vary. On Canon the evaluative (matrix) mode is the only one that uses the confirmed focus point to weigh the exposure. all the others use the the center of the viewfinder. How does Nikon and Sony handle it?
fcotterill
Well-known member
It is Manual or Aperture mode from times past to which more recent ILCs have provided Auto ISO as an option, purely to adjust Sensor Gain
fcotterill
Well-known member
A useful feature on a Nikon Prosumer DSLR is to assign Spot-metering mode to a Fn button to switch between Matrix mode. This is often quicker than press&turn Exposure compensation.
It works well on backlit subjects as the light meter tracks the focus point
It works well on backlit subjects as the light meter tracks the focus point
The problem with spot metering mode is always being able to place the spot on your subject. AND I am always confused if "the spot" is the spot under the focus point OR a central spot. I assume it is the spot being used for AF -- see extracts below.
I note that photographers of HUMANS receive the benefit of Matrix Metering with Face Detection -- and Nikon makes this clear that the faces have to be HUMAN -- Dear Nikon how about applying this to ANY Subject recognised by Subject Detection AF.
Wouldn't that be a great feature -- well it may already work that way -- but on has to dig for it -- and if the subject is small or unevenly lit 4mm may be unhelpful /need EC correction.
I'm sure you know this, but for the OP's sake in his quest to avoid blowing out bright white feathers.
Spot metering is great and can allow you to be very precise in terms of what drives the camera's exposure meter but it isn't a cure-all for blown highlights and the meter still suffers from the same built in limitations, particularly that the meter assumes the world to be mid-toned.
IOW, if you spot meter off white head or breast feathers then you'll still want to dial in some positive exposure compensation to tell the camera those feathers shouldn't be mid-tone gray. Similarly if you spot meter off a black eyeball (assuming you're filling the small spot metering area with that eyeball) or off black neck feathers you'll want to dial in negative exposure compensation to keep those dark parts dark and avoid blowing out brighter areas. If the area under the spot meter happens to be mid-toned then all is great and no exposure comp is typically needed in decently soft light.
The other issue with spot metering is during fast action scenarios where a slight slip in subject tracking or panning can let the spot meter slip off the target and hit the background or a different toned part of the subject and exposure can change wildly. Not such a big issue for static or very slow moving subjects but it can be an issue in action scenarios.
Great tip to keep spot metering handy as it can be very useful in some situations but recurring trouble with blown highlights is really a problem of understanding camera metering and the assumptions built into auto exposure and specifically when to use some positive or negative exposure compensation when shooting in auto exposure modes.
Not surpsingly, Steve has a good video covering this topic as well:
Spot Metering Crash Course - Backcountry Gallery
Wanna get the most out of your spot meter? Did you know that most people think they’re using it correctly but they really aren’t? YIKES – could that be you??? In this video, we’ll go over what spot metering is, where the camera spot meters in the viewfinder, how the spot meter thinks, where it […]
![backcountrygallery.com](https://backcountrygallery.com/spot-metering-crash-course/\"/apple-touch-icon.png\"){kind=icon}
backcountrygallery.com
eaj101
Well-known member
Just to summarize - using matrix metering, aperture priority, shutter priority, and manual with auto-ISO should give you *the exact same exposure*. (assuming the aperture, shutter speed, and ISO stay within 'normal' usable ranges).
That doesn't mean it's the *right* exposure, just that is what the camera decided. You may need exposure compensation if the scene is darker/lighter than everage or you have shadows/highlights that you want to protect.
The Nikon exposure engine is surprisingly smart when it comes to compensating for scenes, though.
That doesn't mean it's the *right* exposure, just that is what the camera decided. You may need exposure compensation if the scene is darker/lighter than everage or you have shadows/highlights that you want to protect.
The Nikon exposure engine is surprisingly smart when it comes to compensating for scenes, though.
The only other thing to be aware of is whether one needs to lock exposure after spot metering or just switch to full manual. I reserve the button that used to illuminate the top LED for that job, reassigning it to exposure lock toggle.
Some folks I've read try to spot meter the brightest object, then add 3 stops to that result to "place" the bright at the right side of the histogram. Too complicated when blinkies do the work for me.
Some folks I've read try to spot meter the brightest object, then add 3 stops to that result to "place" the bright at the right side of the histogram. Too complicated when blinkies do the work for me.
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arbitrage
Well-known member
If light on the subject is fairly consistent (full sun or full clouds) then I don't see why people still use M+AutoISO as it has the risk of ruining exposures based on the color/brightness of the background and the size of the subject in the frame. Best is to just set all 3 variables for your subject and then it doesn't matter what background it is against or how much of that background it is covering up. If you use M+AutoISO you will still need to fiddle with EC to not ruin shots.
The only time I'll switch from full M to M+AutoISO is if I'm in a situation where the sun is constantly going in and out of clouds. Auto ISO can make this type of situation a little easier to shoot especially if the background isn't changing much.
I shoot in full M 95% of the time. I set my aperture wide open (except in a few scenarios), set my SS to freeze the action and set my ISO to give a correct brightness to the image. So most of the time I'm just tweaking the ISO if the light is changing slightly OR I'm changing the SS and ISO if I'm going from a static subject to BIF (although most of the time I have a 2nd back button programmed to do a slow SS/lower ISO for perched birds so I don't have to change my main SS/ISO off of action type settings).
If you shoot in M+AutoISO you will still need to change EC and SS (assuming aperture is mostly just left wide open). So it doesn't really save you any time fiddling with settings vs full Manual.
The only time I'll switch from full M to M+AutoISO is if I'm in a situation where the sun is constantly going in and out of clouds. Auto ISO can make this type of situation a little easier to shoot especially if the background isn't changing much.
I shoot in full M 95% of the time. I set my aperture wide open (except in a few scenarios), set my SS to freeze the action and set my ISO to give a correct brightness to the image. So most of the time I'm just tweaking the ISO if the light is changing slightly OR I'm changing the SS and ISO if I'm going from a static subject to BIF (although most of the time I have a 2nd back button programmed to do a slow SS/lower ISO for perched birds so I don't have to change my main SS/ISO off of action type settings).
If you shoot in M+AutoISO you will still need to change EC and SS (assuming aperture is mostly just left wide open). So it doesn't really save you any time fiddling with settings vs full Manual.
Yes this is all correct.
Ditto all of the above. I don't understand how people shoot BIF with any auto exposure mode and come out with decent results. Bird flying against dark green trees then against bright sky/over reflective water. Unless the bird is truly filling the frame the camera is going to make some radical exposure changes. But yes, partly cloudy days can be problematic when shooting full manual mode. Still it's my choice other than rare occasions with a stationary critter.
To me it comes down to what's changing faster, light levels (e.g. clouds scuttling by or varying levels of overcast) or background tones. For the former, which is common around here with our summer cloud buildups and afternoon thunderstorms, I'll go with Manual with Auto ISO. For the latter under steady light I'll go with full Manual after metering on something mid-toned in the same light. If both lighting and backgrounds are changing a lot it's a tossup as I'll either be playing the exposure comp constantly or changing my manual settings constantly so there's no easy answer when everything is changing.
Truth is, I rarely shoot wildlife including BIF in broad daylight on a clear day so I'm usually dealing with changing light either just around sunrise/sunset or on cloudy or overcast or even stormy days when I do most of my wildlife shooting.
Lot's of ways to skin this cat, but it's worth having a good grasp on when full manual can make things easier and when some form of auto exposure can make things easier and be willing to switch between them as the situation demands.
In the case where background lighting will be changing I always stick w full manual. I use manual w/ Auto ISO when the light is constant on the subject and background. Much like in the film days when I shot Av mode when the light was constant and manual when the subject was moving between dark and light and backgrounds but was in constant light.
joe43
Well-known member
I use Aperture Priority on my D500, D850 and Z9. In fact I have been using it since I got my first camera that had a meter in it. About the only time I use Manual is when I am doing night time or moon photography. Today, it is A priority, auto ISO, and exp comp when needed. If full manual works for you use it. The key is to understand all parts of the Exposure Triangle to get the needed setting for a given image.
I think that bold part hammers the point home pretty well.Old dog, new tricks
The whole thread started as a discussion on A mode vs auto ISO. Assumed you knew what's what
IMO auto ISO is the only auto exposure mode that makes any sense in this day and age. It is rather confusing that the camera companies still refer to it as "manual". I assume trying to avoid confusion during the transition from film but IMO creates more confusion. "Manual mode" isn't necessarily manual exposure. Must be some military minds involved.
In the old days we (well at least I did
) put film in the camera and ISO was fixed. It wasn't unusual to have two cams loaded with different speed film. Then came auto ISO and now I carry two cams with different lenses.... -- It's so darn nice not to be limited to one ISO....
Exposure is the amount of light hitting the sensor.
Correct me if I’m wrong, but exposure depends on three things, not just two: Shutter Speed, Aperture and Luminance. (See Wikipedia.)
Thus, if the scene’s lighting (luminance) changes, for the same shutter and aperture settings, the amount of the light on the sensor changes and so the exposure changes,
ISO invariance means that the sensor sensitivity does not change with a change in ISO. The proportionality between the number of photons (exposure) hitting the sensor and the electrical charge generated remains invariant with the ISO setting. ISO is just a setting of the amplifier gain which makes it easier to see the signal. So, as the available light goes down, the amplifier gain (ISO) is turned up so we can see the smaller signal coming out of the sensor.
With less signal, the overall signal to noise ratio (SNR) is reduced. The SNR will change proportionally with the number of stops the light changes. Less signal means more noises images.
In Manual with Auto ISO, aperture and shutter speed are fixed in return for a trade off in SNR as determined by the camera.
Ain’t no free lunch.
Seems that there is much confusion over what raising the ISO actually does. If you are in a situation where you will be underexposed and are already using the widest aperture and you don't want to slow the shutter, you can increase the ISO. BUT that does not make the Sun make more light - that remains the same. What you are doing is, as has been said, is elecronically amplifying the signal produced by the sensor.