Auto ISO Help Please

[KJRusso]

Hi everyone,

I'm a little confused as to what my Auto ISO is doing. Yesterday I had a practice equine shoot at a barn. I positioned the horse at the door of the barn, facing the light. Behind him, the doors and windows were closed to make it as dark as possible. Unfortunately, there some of the stalls were painted white but in post I go in a blackout most of the background. Anyway, my question is this. For animals portraits, I usually shoot wide open at 2.8 with a minimum shutter speed of 1/500. The sky was still quite bright (I thought) but most of my photos had ISO's of 12,800 which completely shocked me. I don't think the horses look terrible and I'm going to black out the background anyway. But is this normal? I had my minimum ISO set to 100. Is there another setting I'm missing? Should I be using a specific metering mode? I shoot in RAW but exported a jpeg (no editing) to include in this post. Thanks in advance for feedback.

1/1000 sec at f/2.8, ISO 12,800, 180mm, Nikon D750, Tamron 70-200mm

You can only see EXIF info for this image if you are logged in.

 

[jbarton248]

If the lighting isn't changing I'm not too sure that I'd set my ISO to auto, I'd pick 1600 or better in a dark situation, and lower the shutter speed since nothings moving that fast. Shoot it as a portrait, even tho it's a horse.

 

[KJRusso]

If the lighting isn't changing I'm not too sure that I'd set my ISO to auto, I'd pick 1600 or better in a dark situation, and lower the shutter speed since nothings moving that fast. Shoot it as a portrait, even tho it's a horse.

Thank you that is a good suggestion. I have my maximum ISO sensitivity set to 12,800. I guess my second question is why does it only shoot at that ISO? I just went outside to take some photos of hummingbirds (bright light, middle of the day) and my camera is still using the 12,800 ISO to take the photos.

 

[JANuser]

Never seen that kind of behavior from auto ISO before, seems odd that even on a bright day it would be ramping up that high. I've done it by mistake, by accidently ramping up the minimum ISO, but never when it was set correctly. Have you tried resetting the camera to default settings? If not, backup your current settings to a memory card and then press and hold the two buttons with green dots beside them.

 

[JohnW]

Thank you that is a good suggestion. I have my maximum ISO sensitivity set to 12,800. I guess my second question is why does it only shoot at that ISO? I just went outside to take some photos of hummingbirds (bright light, middle of the day) and my camera is still using the 12,800 ISO to take the photos.

You may have set in the menu for auto iso with a max of 12,800, did you confirm your in Auto ISO and not regular ISO. It's very easy to press the iso button and then if you also move the front command dial you'll toggle between Iso and Auto ISO. Could be that you inadvertently switched it to straight ISO instead of Auto ISO. I know I've done that in the past.

 

[kimball]

Steve's latest video has two good tips that may be pertinent to you:

The first, directly linked above to 75 seconds in, has to do with how to quickly turn on/off auto-ISO. Sounds like you may want to use that to double-check you're actually in auto-ISO.

The second tip, at 1:38, concerns watching your default ISO setting while using auto-ISO. It's quite possible you've accidentally set your default ISO to 12,800 and then turned on auto-ISO with a max ISO also set coincidentally to 12,800. If that's the case, your ISO won't drop below 12,800 (or go above it). Keep your default ISO at your camera's base, which for the D750 is ISO 100.

 

[Whiskeyman]

I never set my D750 Auto-ISO to that high an ISO. I normally have it set to 3200, and only go to 6400 when I absolutely have to. IMO, the D750 high-ISO performance at these levels just isn't good enough for shots like these.

For the hummingbird shots you reference, what were the apertures and shutter speeds?

W

 

[MorganP]

In the auto ISO Setup you need to set the low ISO number as well as he high ISO number max. The reason your getting such a high ISO is because you don't have enough light on you subject. Let me say I think you have a very good photo and I would not change much. The light you have coming in from the door is providing enough light to light the horse but it's not strong enough to light the background.
This is going to sound strange but to separate your foreground from the back ground you need to add more light. By adding more light to the subject or to the back background but not both at the same time. Lighting a horse is like lighting a person you might try looking on Ytube or at books to learn the finer points from someone with more experience.

 

[KJRusso]

Steve's latest video has two good tips that may be pertinent to you:

The first, directly linked above to 75 seconds in, has to do with how to quickly turn on/off auto-ISO. Sounds like you may want to use that to double-check you're actually in auto-ISO.

The second tip, at 1:38, concerns watching your default ISO setting while using auto-ISO. It's quite possible you've accidentally set your default ISO to 12,800 and then turned on auto-ISO with a max ISO also set coincidentally to 12,800. If that's the case, your ISO won't drop below 12,800 (or go above it). Keep your default ISO at your camera's base, which for the D750 is ISO 100.

Thank you! I will watch this.

 

[KJRusso]

In the auto ISO Setup you need to set the low ISO number as well as he high ISO number max. The reason your getting such a high ISO is because you don't have enough light on you subject. Let me say I think you have a very good photo and I would not change much. The light you have coming in from the door is providing enough light to light the horse but it's not strong enough to light the background.
This is going to sound strange but to separate your foreground from the back ground you need to add more light. By adding more light to the subject or to the back background but not both at the same time. Lighting a horse is like lighting a person you might try looking on Ytube or at books to learn the finer points from someone with more experience.

Thank you this is very helpful. I was thinking that maybe for next time I will pull the horse out more from the barn and also to stand further back when taking the shot. I will research this more.

 

[DRwyoming]

Thank you that is a good suggestion. I have my maximum ISO sensitivity set to 12,800. I guess my second question is why does it only shoot at that ISO? I just went outside to take some photos of hummingbirds (bright light, middle of the day) and my camera is still using the 12,800 ISO to take the photos.

As others have posted I suspect you accidentally switched the camera back into Fixed ISO at 12,800 when in the barn. Two clues to that are the first horse image was captured with a shutter speed of 1/1000" even though you've said the minimum shutter speed is set to 1/500". Normally the camera would step down to your minimum shutter speed assuming your were shooting in Aperture Priority Auto ISO mode. Then when you went back outside the camera was still shooting at ISO 12,800 which really shouldn't happen unless you stopped the lens down substantially from f/2.8.

Maybe something strange is happening with your camera, but since all it takes is a press of the ISO button and a spin of the sub-command dial to toggle between Fixed ISO and Auto ISO, I'd suspect that somehow you switched back into Fixed ISO operation.

FWIW, for images like your horse portrait you should be able to go well below 1/500" with a 180mm lens so that you can get away with lower ISO in darker situations.

 

[SanDiegoSteve]

Are the images over exposed? That image looks about right to me. If it is exposed right, and you were in a dark barn... maybe it is what you would have needed in full manual.

Now, as others have stated, 12,800 in the sun should look all white and it isn't adjusting. I set my Auto ISO to base ISO and Max of what I'm comfortable with then use Matrix metering. Ex Comp as needed.

 

[Flyboy]

Woops! Posted on wrong photo! Apologies!

 

[Woodpecker]

Hi everyone,

I'm a little confused as to what my Auto ISO is doing. Yesterday I had a practice equine shoot at a barn. I positioned the horse at the door of the barn, facing the light. Behind him, the doors and windows were closed to make it as dark as possible. Unfortunately, there some of the stalls were painted white but in post I go in a blackout most of the background. Anyway, my question is this. For animals portraits, I usually shoot wide open at 2.8 with a minimum shutter speed of 1/500. The sky was still quite bright (I thought) but most of my photos had ISO's of 12,800 which completely shocked me. I don't think the horses look terrible and I'm going to black out the background anyway. But is this normal? I had my minimum ISO set to 100. Is there another setting I'm missing? Should I be using a specific metering mode? I shoot in RAW but exported a jpeg (no editing) to include in this post. Thanks in advance for feedback.

1/1000 sec at f/2.8, ISO 12,800, 180mm, Nikon D750, Tamron 70-200mm

You certainly didn't miss anything on the Auto-ISO apart form may be going ab it too far with the maximum ISO for a D750, because you get High ISO noise and the darker the background - and the subject itself - the more visible it will be. After testing I usually limit my D750 to ISO 6400 and have the menu option for modifying this value in the "My Menu" page so that I can change it if lighting gets difficult but I have brighter background and subject.

But something else strikes me there: Was is freezing cold in the barn to make your horse shiver or move to get warm or did you have a group of barking hunting dogs - or tourists - in front of the door ?

If not, what was the reason to shoot with 1/1000 sec. Until a couple of years ago I shot - sorry, photographed - horses quite regularly and 1/1000 or more I used if trying to nail the photo with the horse going full throttle while playing with the owner's terriers. If the horse bevaves normally I would try shooting bursts, but with considerably lower shutter speed. So I can sort out the blurred ones due to the horse moving suddenly, but I would get much lower ISO. Calulating from ISO 12800 going with 1/250 and afew more photos to be on the safe sideyou would end up with ISO 3200 which is within the comfort zoe for the D750 im terms on High ISO noise and you don't have to spend so much time on processing because you don't need to play with noise reduction.

Due to my girl friend having had a frisian stallion I had to deal with an "All Black" (horse, as opposed to a New Zealand rugby player ), which under this type of condition would have "sucked up" all the noise in the pictures and and at this time I used a camera that didn't even know what ISO 6400 is, but it worked fine by using moderate shuttter speeds. Here's part of the horse - without barn and noise - dreaming into the sunset

You can only see EXIF info for this image if you are logged in.

 

[Woodyg3]

I'm probably missing something in your question, but Auto ISO is simply setting the ISO so as to get the correct exposure with the shutter speed and aperture you have selected. To get a lower ISO you need to use a slower shutter speed and/or wider aperture.

That's a very nice looking horse. I like his white spot on the forehead.

 

[Bristolian]

Something to be aware of with AutoISO is that if you accidentally (or even deliberately) change the ISO value to a higher figure with the rear command dial then the camera will not go below that, even if you've set a lower value in the ISO sensitivity.

 

[Woodyg3]

Something to be aware of with AutoISO is that if you accidentally (or even deliberately) change the ISO value to a higher figure with the rear command dial then the camera will not go below that, even if you've set a lower value in the ISO sensitivity.

Huh, I just tried this with my D500, and the Auto ISO went below the ISO I set manually. Maybe this is not true of all Nikon models?

 

[Deleted member 115]

I'm probably missing something in your question, but Auto ISO is simply setting the ISO so as to get the correct exposure with the shutter speed and aperture you have selected. To get a lower ISO you need to use a slower shutter speed and/or wider aperture.

That's a very nice looking horse. I like his white spot on the forehead.

Exactly, the exposure looks fine the iso is high so something will have to change or not...lol

 

[Icarus]

If I'm using auto ISO, I shoot manual aperture and shutter speed. Gives me good control. I don't want two variables as in auto aperture, auto iso, or auto shutter, auto iso.
you might try that.