ISO Low Settings: My manual for the Nikon D850 lists a normal range of ISO 64 to ISO 25600 and 3 low settings Lo 0.3 ~ISO 50, Lo 0.7 ~ISO 40 and Lo 1 ~ISO 32 plus 4 high settings. I...

The Capt.

My manual for the Nikon D850 lists a normal range of ISO 64 to ISO 25600 and 3 low settings Lo 0.3 ~ISO 50, Lo 0.7 ~ISO 40 and Lo 1 ~ISO 32 plus 4 high settings. I have read that when increasing the ISO above the base ISO 64 that electric current is increased therefore increasing noise but what happens when decreasing ISO below 64? I would expect it to decrease electric current and reduce noise even more. If so why isn't the base ISO lower than 64. I have taken pictures at ISO 40 and not noticed any degradation of quality.

Hanson

Same situation on my Sony. I don't know what the advantage is to set ISO to 50.

BebuLamar

I believe using the low settings would give lower quality than the lowest 64. With those settings the lower ISO are achieved by software and not by lower the gain (which would reduce noise).

The Capt.

By lower quality do you mean fewer colors?

MW

The Capt. wrote:

My manual for the Nikon D850 lists a normal range ... (show quote)

One low ISO advantage is that you can blur moving water (streams, waterfalls, ocean surf) without the hassle of an ND filter. The issue of ISO and noise was a very big deal with early digital photography but has diminished (but not disappeared) over the years. IMO with the latest cameras it’s not worth spending a lot time worrying about unless you are using really high ISO (>3200).

hoola

A very interesting topic . Most digital cameras do not go below 100 iso/asa . Film cameras used to go down as low as 16 iso/asa . When I do still life using flash this is a problem . My flash will not power down low enough to give me f -stop I want to be at . Yes I could use ND filter(on either lens or lighthead) but that would darken/dim my view . Funny most folx I think want a camera with high iso/asa but myself I'd rather have a camera with low asa/iso setting ability .

The Capt.

MW wrote:

One low ISO advantage is that you can blur moving water (streams, waterfalls, ocean surf) without the hassle of an ND filter.

Yes, that is why I went down to ISO 40.

BebuLamar

delete

The Capt.

Thanks everybody.

Ysarex Loc: St. Louis

The Capt. wrote:

My manual for the Nikon D850 lists a normal range of ISO 64 to ISO 25600 and 3 low settings Lo 0.3 ~ISO 50, Lo 0.7 ~ISO 40 and Lo 1 ~ISO 32 plus 4 high settings. I have read that when increasing the ISO above the base ISO 64 that electric current is increased therefore increasing noise but what happens when decreasing ISO below 64?

That's not accurate. There's no electric current being increased or decreased. You do have a camera with dual impedance channels so there is a current change that takes place when you switch from ISO values below 400 to values of 400 and above.

With the ISO values below 64 your camera simply implements ISO in the camera image processor. No change to implement ISO takes place in the creation of the raw file. You do run the risk of clipping highlights with the increased exposure assuming you follow the the camera meter -- 32 is a full stop more exposure.

This may help explain what's happening: https://www.photonstophotos.net/Charts/PDR.htm#Nikon%20D850

The Capt. wrote:

I would expect it to decrease electric current and reduce noise even more. If so why isn't the base ISO lower than 64. I have taken pictures at ISO 40 and not noticed any degradation of quality.

bleirer

The Capt. wrote:

My manual for the Nikon D850 lists a normal range ... (show quote)

I shoot Canon, but this is what my manual tells me: As L (equivalent to ISO 50) is an expanded ISO speed setting, the dynamic range will be somewhat narrower compared with the standard setting.

I bet Nikon is similar.

CO

That's a good topic to bring up. I just selected the D850 in the DxO sensor comparison tool. Both the signal to noise ratio and the dynamic range improve all the way to the lowest ISO (under ISO 50 on the charts).

(Download)

Ysarex Loc: St. Louis

CO wrote:

That's a good topic to bring up. I just selected the D850 in the DxO sensor comparison tool. Both the signal to noise ratio and the dynamic range improve all the way to the lowest ISO (under ISO 50 on the charts).

Interesting then as Bill Claff's data says the opposite: https://www.photonstophotos.net/Charts/PDR.htm#Nikon%20D850

bleirer

Ysarex wrote:

Interesting then as Bill Claff's data says the opposite: https://www.photonstophotos.net/Charts/PDR.htm#Nikon%20D850

strange. My canon doesn't lose anything below 100 either on that chart.

CO

Ysarex wrote:

Interesting then as Bill Claff's data says the opposite: https://www.photonstophotos.net/Charts/PDR.htm#Nikon%20D850

No. They're very close to the same. The DxO chart of dynamic range shows an almost flat graph around ISO 50. The Photons to Photos chart shows the graph to be flat around ISO 50.