NikonGear'23

Gear Talk => Camera Talk => Topic started by: jpgrahn on January 04, 2018, 16:44:54

Title: D800 - optimal ISO
Post by: jpgrahn on January 04, 2018, 16:44:54
I saw something mentioned in a camera review by Thom Hogan.
He talked about optimal ISO values for the D5.
My question is:
Are there "better" ISO-values in the D800?

I usually only use steps from 100 to 200, 400, 1600 etc.
Would it be better to use different ISOs?
One article mentioned the series 160, 320, 640 etc.
Title: Re: D800 - optimal ISO
Post by: armando_m on January 04, 2018, 18:17:25
I use 1 step values and get good results, if i use auto-ISO for whatever reason it uses the fractional values, and I have not really noticed any difference
Title: Re: D800 - optimal ISO
Post by: pluton on January 04, 2018, 20:09:40
Like Armando, I normally set only full-step ISO values on my 2 D800's. 
The two reasons I got the D800's was to get increased resolution over my previous D3 cameras, and to whatever extent possible minimize the noise present in underexposed files.  On both counts, I got the improvements I wanted.
As far as I can tell, the D800 follows conventional thinking on high ISO vs. noise.  Underexposure = more noise in the rendered file.
It has been proposed by 'experts' that the intermediate ISO steps (like 320, 500, etc) bring in additional processing on the raw file by the camera.  I have not attempted to test this because I'm generally happy with the pictorial results from the D800 as I currently use it.
The D5 is said to have special processing applied to the raw file when the ISO setting is upped from base level, which may explain test results that show 'better looking files' at higher ISOs than at base.
Title: Re: D800 - optimal ISO
Post by: jpgrahn on January 04, 2018, 20:33:40
I have also mainly kept my settings to ISO 100, 200 etc. I skip the intermediary steps. Maybe mostly by habit from the film days.
Films didn't come in just every possible ISO setting.
Rarely do I use Auto-ISO but I can see the benefit of it. If I really only want to use a specific shutterspeed and a specific aperture value.
But otherwise I mostly stick to either manual settings or the A-setting on the camera.

With the D800 being as good as it is already I probably don't need to worry too much about this.
For my type of photography at least.
Title: Re: D800 - optimal ISO
Post by: David H. Hartman on January 04, 2018, 21:56:52
I've read that intermediate ISO, e.g. 125, 160, 250 are fine to use. I don't know where and I don't know when. The same article mention other cameras where there was no advantage to using intermediate ISO(s). Naturally I try to stay with ISO 100 or 200 when possible for the dynamic range.

Dave
Title: Re: D800 - optimal ISO
Post by: Hugh_3170 on January 05, 2018, 03:22:15
Why would the intermediate ISO settings not be good to use?

On a digital camera, the ISO setting is really an indication to the cameras analogue to digital conversion processes as to how much amplification that the signal output from each pixel (or photo site) should receive to arrive at an acceptable exposure.
Title: Re: D800 - optimal ISO
Post by: Jack Dahlgren on January 05, 2018, 04:07:42
I almost always set the camera to manual and use auto-iso to take up the slack. I’ve not noticed that intermediate speeds are particularly problematic.
Title: Re: D800 - optimal ISO
Post by: jpgrahn on January 05, 2018, 08:14:09
Why would the intermediate ISO settings not be good to use?


This is exactly my question.
In our long struggle to reach the ultimate quality, technical quality, maybe this particular area is nothing to worry about anymore.
I have seen it mentioned that certain ISO values were less good than others but I wanted to get some confirmation.

Title: Re: D800 - optimal ISO
Post by: elsa hoffmann on January 05, 2018, 10:01:31
I almost always set the camera to manual and use auto-iso to take up the slack. I’ve not noticed that intermediate speeds are particularly problematic.
+1
Title: Re: D800 - optimal ISO
Post by: Seapy on January 05, 2018, 10:16:14
My understanding is that digital sensors have one base, or natural ISO and all others are achieved by amplification and attenuation of the base signal, hence 'noisy' high ISO; a bit like a faint HAM radio signal from half way around the world needs a lot of amplification, so  does a faint image. In neither case are you likely to get a clear result.  I believe for most sensors the base, or natural ISO has been 200 ISO but perhaps recently that may have dropped to 100 ISO?

Amplification and attenuation has come a long way since the D1.

Using an ISO  below the natural ISO for the sensor, if seeking a better image, rather than simply a longer exposure, may be a wild goose chase.

As for the intermediate settings, I firmly believe when somebody is *looking* for a problem, they will find one, then perhaps attribute it to the wrong cause.
Title: Re: D800 - optimal ISO
Post by: Seapy on January 05, 2018, 10:24:26
I almost always set the camera to manual and use auto-iso to take up the slack. I’ve not noticed that intermediate speeds are particularly problematic.

Good way but don't be tempted to try that in aperture priority as I did when I first got my D3!  ::)   The  results are garbled! (Messy!).  Coming from the D1 + D200, auto ISO was something of a novelty...
Title: Re: D800 - optimal ISO
Post by: Ilkka Nissilä on January 05, 2018, 10:58:47
Fractional ISO settings should be fine on the D800.

In some cameras there are ”jumps” in the dynamic range vs. ISO curve. If you are trying to minimize shadow noise in such case you may want to select the ISO deliberately at some values and not others. But even in such cases the midtone and highlight SNR would still improve when taking a fractional step down in ISO (even though the deep shadows may take a small hit).

But the D800 doesn’t have this kind of discontinuities, as far as I know.
Title: Re: D800 - optimal ISO
Post by: Airy on January 05, 2018, 13:52:28
which I confirm.

I use auto ISO most of the time, the limit being set (for my taste & use cases) at 6400. I could not observe any discontinuities, nor are any revealed by measurements published e.g. by DXOmark.
Title: Re: D800 - optimal ISO
Post by: longzoom on January 05, 2018, 18:47:36
which I confirm.

I use auto ISO most of the time, the limit being set (for my taste & use cases) at 6400. I could not observe any discontinuities, nor are any revealed by measurements published e.g. by DXOmark.
   Same do I, with one only different - my Auto ISO is 12800. So the upper image at ISO 12800,  and my granddaughter pic (from family album!), with crop,( D810, in both cases) at ISO 5000. Do you admit any significant difference to the base settings? The D800 and 810 are equal in this department. 80-400G lens. LZ.  ca(https://farm5.staticflickr.com/4168/34188790950_2a0caf5422_b.jpg) (https://flic.kr/p/U69uqW)2017-04-16 004-1-2-1 (https://flic.kr/p/U69uqW) by longzoom[/url[url=https://flic.kr/p/EmfA61](https://farm5.staticflickr.com/4539/25170733338_83e2a28af2_b.jpg) (https://www.flickr.com/photos/longzoom/)2017-12-09 049-1 (https://flic.kr/p/EmfA61) by longzoom (https://www.flickr.com/photos/longzoom/), on Flickr], on (https://farm5.staticflickr.com/4691/38156549865_80c6f66769_b.jpg) (https://flic.kr/p/218LhVp)2017-12-09 049-1-2 (https://flic.kr/p/218LhVp) by longzoom (https://www.flickr.com/photos/longzoom/), on FlickrFlickr
Title: Re: D800 - optimal ISO
Post by: Jack Dahlgren on January 06, 2018, 02:33:40
   Same do I, with one only different - my Auto ISO is 12800. So the upper image at ISO 12800,  and my granddaughter pic (from family album!), with crop,( D810, in both cases) at ISO 5000. Do you admit any significant difference to the base settings? The D800 and 810 are equal in this department. 80-400G lens. LZ.

For most things I photograph I set max auto-iso on Df to 10k, but will usually dial down shutter speed or aperture if I see ISO heading up to that territory. If I can keep around 3200 I’m happy. It certainly depends on subject matter and other variables, but I find shooting this way gives me easy and fast control over the things I want to control and sacrifices image quality to make that possible.
Title: Re: D800 - optimal ISO
Post by: longzoom on January 06, 2018, 04:02:15
For most things I photograph I set max auto-iso on Df to 10k, but will usually dial down shutter speed or aperture if I see ISO heading up to that territory. If I can keep around 3200 I’m happy. It certainly depends on subject matter and other variables, but I find shooting this way gives me easy and fast control over the things I want to control and sacrifices image quality to make that possible.
     I do agree. And yes, I may sacrifice image quality, too,  to some degree, of course! Our life is full of compromises, for sure... LZ
Title: Re: D800 - optimal ISO
Post by: Airy on January 06, 2018, 04:40:17
For most things I photograph I set max auto-iso on Df to 10k, but will usually dial down shutter speed or aperture if I see ISO heading up to that territory. If I can keep around 3200 I’m happy. It certainly depends on subject matter and other variables, but I find shooting this way gives me easy and fast control over the things I want to control and sacrifices image quality to make that possible.

Same here, but for limit (12800 on Df). To achieve this, the camera is in A mode, auto ISO with speed set to 1/2*FL, and I prepare the manual mode with speed set at 1/FL ; in dim light situations, I switch to M mode, so the manipulations are minimal - I only regret that the Df mode switch requires one to remove the camera from the eye.

The other important parameter is exposure compensation, but that's not the subject here. As regards aperture, I do not regard it as a parameter that should be primarily affected by exposure because it is primarily about subject isolation (and, possibly, aberration elimination or contrast reduction). So the choice range is narrow.