Auto ISO or Fixed ISO-- Opinions needed

[Braineack]

I've also learned that if you don't properly expose images, and use the DynamicRange to pull exposures up, you can introduce noise. So it's better to get the exposure correct in camera, rather than pull it out in post.

Pretty certain if you shoot at 100 ISO and underexposed the shot by 5EV, and then recover in post, there would really be no difference, IQ wise, if you had shot it the same at 1600 in the first place.

go test it sometime.

When/if we ever get intelligent auto-ISO that doesn't crank up to maximum in dim light when you are using flash I might use auto but for the time being since auto-ISO is so dumb I'll stick with the manual ISO mode.

Auto-ISO with flash is balancing the ambient and flash exposure by jacking up the ISO. With TTL and based on your metering, without a high ISO you probably won't have enough flash power to fully light the entire room and subjects, so it brings up the ISO so the room lights come into play with the exposure. otherwise with a low ISO the flash will be unable to get a good exposure on both the subject and background to make your meter happy. Or you just deal with the dark background in shots and bright subjects. or drag the shutter and get cool light trails. This also keeps the flash power in check so you're not dumping full power blasts and depleating the battery fast.

One way around this is to use more than one tiny little light to light up an entire room and subjects.

 

[Peeb]

Took these for another thread, but in hindsight they were shot on M at 1/1000 f/8 and auto ISO (camera selected 320).

 

[Didereaux]

Took these for another thread, but in hindsight they were shot on M at 1/1000 f/8 and auto ISO (camera selected 320).
View attachment 115588

" M at 1/1000 f/8 and auto ISO" ....the bird shooters holy Grail! lol

 

[Ysarex]

I've also learned that if you don't properly expose images, and use the DynamicRange to pull exposures up, you can introduce noise. So it's better to get the exposure correct in camera, rather than pull it out in post.

Pretty certain if you shoot at 100 ISO and underexposed the shot by 5EV, and then recover in post, there would really be no difference, IQ wise, if you had shot it the same at 1600 in the first place.

go test it sometime.

Yep, at least on a Nikon 610.

Joe

 

[Peeb]

Took these for another thread, but in hindsight they were shot on M at 1/1000 f/8 and auto ISO (camera selected 320).
View attachment 115588

" M at 1/1000 f/8 and auto ISO" ....the bird shooters holy Grail! lol

I know, right??

 

[TCampbell]

If I expect lighting conditions to change rapidly then I'll use auto-ISO. If I can see that the conditions are fairly consistent (w.r.t. lighting) then I typically pick an ISO.

I'm not a "gotta use manual and only manual" person. If conditions change rapidly, then manual is not your friend. When things are changing quickly, it's time to lean on the computer in the camera to help out.

 

[Overread]

The only thing that makes me not use manual mode with auto ISO more often is that the 7D has no compensation ability for exposure when using auto ISO in manual mode. Thus if the camera meter is underexposing in the light or overexposing I can't control that - which pushes me off auto ISO in some cases where with either other modes or fully manual I can get better results.

It will make you learn to work with higher ISOs, but in general its a very powerful and freeing mode; especially when you know the ISO is the only thing you'll be varying for most of the shots.



I think the 7D MII and some other newer camera have a compensation ability - and Nikon have had exposure compensation in manual mode for years (though I don't know if it will actually change the auto ISO value or not or if its only changing how the meter displays the light info to the user)

 

[Braineack]

I've also learned that if you don't properly expose images, and use the DynamicRange to pull exposures up, you can introduce noise. So it's better to get the exposure correct in camera, rather than pull it out in post.

Pretty certain if you shoot at 100 ISO and underexposed the shot by 5EV, and then recover in post, there would really be no difference, IQ wise, if you had shot it the same at 1600 in the first place.

go test it sometime.

Yep, at least on a Nikon 610.

Joe

It's kinda how all digital cameras work...

from my crop sensor:

colors got a little off here, but that may have been something i did. this was just quickly done sitting here on the couch with a cat in my lap. IQ-wise, they are pretty much identical. All you're doing by turning up the ISO is basically moving the EV slider to make the light meter happy -- in camera might process it a bit better, but all-in-all it's the same idea. If I tossed the color, you would have no idea which was which.

 

[Derrel]

If you find yourself correcting for noise on most edits of images shot with a Nikon D610, the chances are that the exposure levels you are giving are not adequate, that you are in a word, underexposing. As several people have mentioned, the idea of a D610 producing noise at low ISO values in an indication that something is not quite right. I would classify the problem you're having as a systemic error--something in YOUR system is askew.

The D610 is a sophisticated camera with a LOT of custom control options. What might be askew? Could be any of the following things: mis-calibrated light meter. Accidentally set exposure compensation dialed in and left set to Minus exposure level. Accidental use of spot metering or a very,very small-area center-weighted setting (this is user-adjustable). Bent or faulty diaphragm actuation system, either in-body or on a particular lens. Software issue with how .NEF files are converted in Lightroom or ACR. Forgetting to actually use the light metering system.It is possible that the Fine Tune Optimal Exposure setting has been adjusted: this is user-adjustable, but does NOT "show up" through the viewfinder! Custom setting b5 is this one I believe on the D610--it was on the D600.

The Easy Exposure Compensation system might be set to ON, instead of On with(AutoReset). I think this is Custom Function, b3. This will STAY put even if the camera has been turned off and turned back on!

Anyway…you should NOT have noise at LOW ISO values with a D610 is the exposures are adequate. I would suggest resetting the D610 to factory defaults. Here is a web page that shows how to do that (on the D610 it is a two-button, press-and-hold type reset). How To Reset Nikon D610 DSLR Camera

Without at least a few test images with EXIF info, we're shooting in the dark, but there ARE a few possible system adjustments that could be causing this issue.

Another very common "systemic error" results from people who set exposure values by shooting a test shot, then looking at the rear LCD, and judging exposure based on a rear LCD image that is set to maximum brightness. This is pretty common.

Again--do a two-button reset of the camera. Something is likely wrong within your overall "system" or way of exposing images. With the U1 and U2 settings, it's possible the camera has been accidentally configured in a wonky manner. Again, without sample images and a very detailed rundown of exactly HOW YOUR D610 is configured and how YOU are using it, the above are just the general, common problem areas I can think of for a D610 that's consistently turning in noisy shots. See if re-settting everything back to factory defaults eliminates the issue.

 

[Overread]

Just a point - in general noise is always lower with a higher ISO in camera over brightening in editing. Certainly newer sensors are getting it to a point where the difference is minimal and in some cases might be invisible; however I would argue that its good practice to always try and attain the best light gathering in-camera. That ensures that when you do start using very high ISOs you are already shooting with a method that will give you the best possible result.

Do all you can in-camera to get the best possible result; that will give you the best to work with in editing and can lower your editing time and also mean that you can do some more extreme editing a lot more because you've got the good light data to begin with (some of those I know who do a lot of editing are really focused on getting it right in camera because they know that they can't do the extreme editing without that data)

 

[JerryPH]

"Pretty certain if you shoot at 100 ISO and underexposed the shot by 5EV, and then recover in post, there would really be no difference, IQ wise, if you had shot it the same at 1600 in the first place."
"go test it sometime."
Yep, at least on a Nikon 610.

It's kinda how all digital cameras work...

View attachment 115648

View attachment 115649
colors got a little off here, but that may have been something i did. this was just quickly done sitting here on the couch with a cat in my lap. IQ-wise, they are pretty much identical. All you're doing by turning up the ISO is basically moving the EV slider to make the light meter happy -- in camera might process it a bit better, but all-in-all it's the same idea. If I tossed the color, you would have no idea which was which.

Wow, something is really wonky here... that you can actually get similar exposures with the camera set to ISO 400 and ISO 3200 and all the other camera settings identical?? Man there is something strange going on there... like a ton of manipulation in post to correct for the 3 stops in exposure that there SHOULD be.

If you had shown 1/60th@F/5.6 and ISO 400 and 1/500th@F/5.6 and ISO 3200, THEN you have matching exposures. No man, your samples are not accurate at all, and then even your colours go all off.

BTW, in all cameras, there is a lot more happening in between ISO 100 and ISO 1600. A D610 loses probably a good 2 stops of dynamic range in that range as well as introduce a small amount of noise.

The golden rules to shooting high ISO are:
1. First and foremost, NAIL the exposure. Get it wrong, toss the photo out right there.

2. KNOW your camera. When it comes to higher ISO and how it affects your camera, go to a dark location and take 30 minutes and play. By dark location, I suggest places that start at 1/60th@F/2.8 at ISO 6400. Those are the kinds of places that separate the men from the boys... lol

3. Its no sin to use noise reduction in post process. In fact, removing noise in post is far superior to removing the noise in camera. In fact, mine is never turned on at all.

4. Shoot the highest resolution of RAW that your camera gives you.

When I first got my D4, I didn't see many articles about how well it REALLY did in real life. I learned fast that this camera shoots at ISO 6400 the same way my D700 shot at ISO 1600, and that I could EASILY get a useable shot at ISO 204,800, and pretty good shots 1 stop lower at ISO 102,400. Anything less was usable professionally even on larger prints with a touch of noise reduction in post.

Concerning auto ISO... I *never* use it, not in fast pace situations, not in slow paced situations. I set it for the LOWEST settings that get me the shot, and to do that, it helps a lot if your hand holding technique is good, because that way you can shot that scene at 1/15th of a second and F/2 and ISO 1600 instead of needing 1/125th, F/2 and ISO 6400 on a 50mm lens. I practiced for many hours to squeeze the most out of my camera and especially the longer lenses like the 135mm F/2 and the 70-200mm at F/2.8 and 200mm, and even today I often go into dark places (I love churches, they are inspiring as are many dark places In the city at night!) to keep sharp.

Nikon D700, ISO 1600 F/1.8 and a shutter speed of 1/15th of a second @ 20mm, 100% hand-held.
If you were there, you would not even see ANY details of what is inside the case.

D4, 20mm at F/2, ISO 12,800. I needed 1/25oth to freeze motion. At 1/125th his face, hands and hair motion blur, not something that I wanted.

Finally, how abut ISO 102,400 at F/2 and 1/30th on a D4 in a dark location with the 135mm lens and hand held? Ok, here you go. In real life this location was so dark, you could not make out the vents to the right of the light!

A few years ago a nice kid and I went through the old "camera makes no difference" debate. So I asked him to grab his camera and follow me into the church I usually go to... it starts at F/1.8, ISO 6400 and 1/15th... and gets darker from there (yes that is a completely candle lit room!).

At the end of the visit we both promised to post our pics in the forum. The next day, I posted mine... and he never came back to that forum ever again and never posted even one shot. I guess his camera did not fare very well.

My point was not that a good camera can take good pics, but that a knowledgeable user can take a great camera and get better results than with a good camera under challenging situations.

Anyways, that's my thoughts about high ISO in a nutshell.

 

[beachrat]

Great post Jerry.
Seriously.

 

[Braineack]

Wow, something is really wonky here... that you can actually get similar exposures with the camera set to ISO 400 and ISO 3200 and all the other camera settings identical?? Man there is something strange going on there... like a ton of manipulation in post to correct for the 3 stops in exposure that there SHOULD be.

I wasn't shooting the same exposure. I purposefully underexposed it by 3 stops using ISO only, then recovered in post, you can see the EV slider.

there's nothing strange. this is how ISO in digital cameras work.

The same amount of light was captured and recorded in the image sensor in both shots. The only difference being what we consider to be 100% light. The shot at 1600ISO just displays the RGB values much brighter than actually recorded -- this is essentially the same thing as bumping the EV slider back up in post form the 400 ISO shot. I used my a6000 to shoot those and only moved the EV slider.

here, ill do it again on my D600 sitting right here, right now:

shoot, the time setting on my camera is wrong ARGH.

If you had shown 1/60th@F/5.6 and ISO 400 and 1/500th@F/5.6 and ISO 3200, THEN you have matching exposures.

this is not what I was demonstrating here. This is a much different concept -- there's a difference is how much light was captured and you're basing your metering off a difference scale.

 

[Braineack]

something more extreme:

you sensor captures light based on the aperture and shutter speed. Understanding this is important.

 

[Derrel]

The issue Braineack is demonstrating is now being called "ISO invariance".

It is a relatively NEW capability, made possible by newer sensor technology, and huge advances in software processing. This first time I ever saw this capability, to take a BLACK FRAME that was seven stops deliberately under-exposed, and to then "lift" the blackness veil, and to create a usable image, I first saw back when Sony premiered its revolutionary Exmor sensor technology.

The ability to control and manipulate and adjust highlights and shadows, separately, and automatedly, without user-created masks, was developed by Adobe after over a decade of research and effort. There has been a fundamental change in HOW a digital image can be exposed in the studio or in the field, and there has also been a fundamental improvement in the way newer raw converter software can handle deliberately under-exposed RAW captures!

And yet, we STILL have people who are preaching outdated expose to the right (ETTR) dogma as if it is still applicable to all cameras.What we once took as Gospel Truth has been changed, fundamentally, by newer sensors, newer in-camera electronics, and by newer, smarter software! Things have changed! And this is why Auto ISO shooting in constantly-changing lighting makes total sense now, especially for Nikon shooters, who can use Exposure Compensation AND Manual exposure setting, to get a specific, desired combo of f/strop and shutter speed AND the right "offset" from the light meter to get what they want in the final image, even if a bird drops from a brilliant sky to deep, dark green water in a 2.5 second dive. This is why so many top bird shooters have moved to Auto ISO for things like bird in flight shooting..

It is now possible to deliberately under-expose a shot, in order to get a deep depth of field and/or a high shutter speed, and then, with a **modern** sensor, and with **modern** software, to "lift" the shadows, without creating a huge noisy mess, and while maintaining pretty good dynamic range, and while keeping highlight values protected from over-exposure and blowing out.

Welcome to the new era.