I am due an upgrade in equipment, currently have the D2Xs, was thinking of the D4, but they priced that too high, so I am going to go for the D800( if it becomes avialable that is!). That is where I am, my question is this, the base ISO is 100, but ISO 50 is possible, as this is not the base ISO I assume something has to give when using this. Can anyone explain how they achieve the ISO 50 and what do we lose by using it, dynamic range, image quality?
Obviously I don't have a D800, but if it's like a D3, the pull stop has objectively lower dynamic range - bclaff usually measures these things - but for all photographic purposes I have found, it just doesn't matter. I have absolutely no reservations at all about simply dialing my D3 down to ISO Lo 1 if I need a little wider aperture or a little slower shutter speed. Lightroom tells me that a good 20% of the exposures on my D3 were shot at Lo1, so I do have some experience with this.
_____ Brian... a bicoastal Nikonian and Team Member
My gallery is online. Comments and critique welcomed any time!
This is an awful picture, but like a prior post it shows the great dynamic range. I was trying to shoot water falls, and the sun came out bright. The water itself is burned badly, and behind the bridge is deep shade. I ended up doing some HDR that was almost acceptable, but this is a stright shot without any HDR at all under extreme range of light. It is ISO 50 at F19 and 1/20th second.
My point is not that it came out good (it did not), but that you can see both water texture in the sun-bright foreground, and also still see detail in the deep shadows under the bridge.
Yes, ISO 50 works nicely.
My understanding (very loosely) is that below 100 and above 6400 the sensor is no longer tracking quite to spec, e.g. on some of those straight line graphs it will drop off or up. However I looked at the DXO graphs, and I do not see it for the D800 or D4, so I am not at all sure I understand why it is "LO.1" instead of "50". Comments welcomed on pictures: Http://captivephotons.com
Thanks for the replies and the example images, for the type of shots I take (on the D2 most of mine are at ISO100) I am looking forward to being able to use 50 as well as the higher ISO's as above 400 ISO images from the D2 start to deteriorate rapidly and I have to reach for the strobes! Take care, Dan.