Well, it's not quite that simple. Yes, the correct first-order answer is to disable long exposure noise reduction. That is in fact what is consuming the time. You should be seeing "Job NR" blinking in the top LCD while this is happening. Whether or not you should disable the feature it is a different question. LENR is there to remove what's sometimes called "amp noise" - thermal buildup in the electronics, particularly in some parts near the sensor, can and often does cause fairly obvious errors in color rendering. Here's an example from a different camera:
Yes it's a terrible photograph, but it's pretty good for illustrating this problem even if for nothing else. The nut behind the viewfinder was pretty loose in this instance. The pinkish glow in the upper and lower right corners is NOT part of the image, or at least it's not supposed to be. That's amp noise, created by having some hot electrical components near those locations. I can't find the image at the moment, but one of my other cameras produces darker pink amp noise blobs on the center-left top of a landscape format frame.
Depending on your post processing skills, the content of your images, and the nature of the amp noise produced by YOUR camera model, you may be able to avoid the LENR time for some images. It is worth noting, however, that because this is a thermal problem, environmental conditions make a difference. This example was shot on a hot summer night; if memory serves it was probably still in the mid-80s (F) when this was taken. It is also relatively speaking not as bad as some as it was only a 15 second exposure. Had this been shot at 25F or worse, at -5F, and perhaps for 100 seconds, the amp noise would have been much more visible and probably also different. It's another file I cannot seem to locate, but I have another shot from this same camera (a D2h) shot at about 20F that shows not two but three amp noise blobs. Attachment#1 (jpg file)
_____ Brian... a bicoastal Nikonian and Team Member
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