D700 baseline sensitivity

[borgis_karl_johan]

<p>I just wonder: what has caused Nikon to abandon 100 ASA as baseline sensitivity in the D700? Technical or marketing reasons or some other cause I cannot fathom at all? With 200 ASA it may be difficult to use large apertures on a bright day without resorting to neutral density filters and the like. And yes, I know that you can adjust sensitivity to -1 but why the hassle and not 100 ASA as a straightforward choice?</p>

[rarmstrong]

<p>Borgis, this is a portion of a nice review that will answer your question, based on the 2006 standards for manufacturing sensors...<br>

The <em>Recommended Exposure Index</em> (REI) technique, new in the 2006 version of the standard, allows the manufacturer to specify a camera model’s <a href="http://www.photo.net/nikon-camera-forum/#Exposure_index">EI</a> choices arbitrarily. The choices are based solely on the manufacturer’s opinion of what EI values produce well-exposed <a title="SRGB" href="http://www.photo.net/wiki/SRGB">sRGB</a> images at the various sensor sensitivity settings. This is the only technique available under the standard for output formats that are not in the sRGB color space. This is also the only technique available under the standard when <a title="Metering mode" href="http://www.photo.net/wiki/Metering_mode#Multi-zone_metering">multi-zone metering</a> (also called <em>pattern</em> metering) is used.<br>

This is the entire article, the second portion explains the digital sensor issue...<br>

<a href="http://en.wikipedia.org/wiki/Film_speed">http://en.wikipedia.org/wiki/Film_speed</a></p>

[ilkka_nissila]

<p>If low ISO were that important to many people, the camera manufacturers would surely implement it. The ISO setting range is implemented by adjusting the gain of analog amplifiers. There is a limit to how large a gain adjustment range can be implemented without compromises. Image quality at high ISO settings is a priority for Nikon and many photographers, so they drop out the lowest sensitivities. The D3X has ISO 100.</p>

<p>I do dance and circus photography sometimes and I would like to do some controlled blurring of the movement in daylight. I can't do thatwithout getting a strong ND filter that makes autofocus and viewing the subject more difficult - unless I'm lucky and it's a darker than usual (overcast/rainy) day.</p>

<p>One possibility is to use Rollei ATP which is ISO 32 (black and white). Another is simply use ISO 100 color film like Ektar or Reala and overexpose it by a couple of stops. Should still yield good results. Velvia is ISO 50. I think there are still plenty of options for low ISO if you're willing to use film.</p>

[mac_mcanirlin]

<p>I would certainly like to have slower shutter speeds. Not regularly, but occasionally would love to be able to set as low as iso 25, instead of having to use ND filters. Seems like it should be easy enough to do, but what do I know...</p>

[carl_becker2]

<p>I am sure Nikon has researched the market needs and wants to produce a good selling item. High ISO and zooms seem to be what most want. I have a D700 for high ISO among other things. I would like to see another sensor come out that has a much lower base like 25 or 50. </p>

[eric_chiu2]

<p>Its not marketing reason but technical reason. I recommend you stick with min ISO 200, don't go -1 because from lab test result I read from some magazine that if you push down the ISO to -1, the dynamic range will dramatically reduce. You will not get the detail back from locations are over exposed. If its too bright to use ISO 200, use a smaller apeture. Remeber the old time when using film, we stick with the ISO anyway.</p>

[borgis_karl_johan1]

<p>As other postings point out as well, ISO 200 is somewhat impractical in bright sunlight as even 1/8000th of a second may not be short enough to allow you to use the large aperture you may wish to use. So if the D200 has 100 ISO, why abandon it in the D700?<br>

And sorry, the mathematics in the wikipedia feature referred to above aree beyond my humble mental faculties.</p>

[borgis_karl_johan1]

<p>Has anyone in this esteemed forum ever used Agfachrome 1000? Once in the dim analog past maybe early 1980 I used to carry it for bad light conditions along with a regular ASA 50 or 100 film- the brand varied (Fuji- Ekta- Kodachrome).<br>

I am unsure whether this film was ever marketed in the US. Contrasted with the images that ASA 1000 slide film rendered ANY digital image with the D200 is heavens :-)<br>

Now please do not take this comment TOO seriously...</p>

[borgis_karl_johan1]

<p>Excuse me, this comment is meant to go to another forum!</p>

[rodeo_joe1]

<p>Has nobody read their D700 manual or examined the menus properly? The D700 is perfectly capable of being set to 100 ISO, and the addition of an only slightly grey 2x ND filter (or a polarizer at a pinch) will take it down to 50 ISO. And how about stopping your lens down - ever thought of doing that?</p>

<p>There's a limit to the range of ISO that can be achieved with one sensor and one amplifier circuit in a DSLR, and I'm sure that most users wouldn't want to throw away the practically noisless 6400 ISO capability of the D700 for the sake of a seldom-used low ISO feature.</p>

<p>Stop whining about the technical miracles that modern DSLR designers have given you and go take some pictures!</p>

[borgis_karl_johan1]

<p>Hello Rodeo Joe,<br>

how about reading the posts carefully... :-)<br>

This is about an instance when you using a fast lens on the D700 in bright daylight do NOT wish to close the aperture down. Which is perfectly legitimate, isnt it? Then the lack of easy- access ISO 100 and lower seems inconvenient. Who wants to screw a ND filter on and off all the time?</p>

[carl_becker2]

<p>At times I am in bright light and want to show motion. Due to defraction I do not want to stop down more than f11 with most of my lens kit. I may want a 1 sec exposure. I suspect there are techincal limits that do not allow a design to go from 25 ISO to 6400 ISO. Being able to go below ISO 200 is one thing, weither or not it is good to do is another. I can stop down to f22 but its not really a good idea if I want max sharpness on all of my kit. I have read about lower IQ when going below the base ISO but have yet to try it. I know I can put ND filters on to increase exposure but that can also make focusing an issue. I do enjoy the abilities of the D700 but feel they are limited in regards to lower ISO. It would be even more limiting if I wanted a shallow DoF in daylight plus trying to show motion. There may not be a demand for lower ISO but I do feel there is a use for it. Heck it could have a great manual focus screen and no flash on top either.</p>

[rodeo_joe1]

<p>If you don't like the specification of the D700, then why did you buy it?</p>

<p>The resolution limit of the D700 is under 60 line pairs/mm, so diffraction will have a minimal effect on that resolution until about f/22. And once set up in the menu, the low ISO limit of 100 is just as easy to get at as any other sensitivity - just press the ISO button and turn the thumbwheel. Also the D700's screen is bright enough and its autofocus sensitive enough that you can fit an ND filter and hardly notice the difference.</p>

<p>Tell you what, fitting an ND filter is a lot easier than swapping film backs or changing to a body that's got Kodachrome 25 loaded and then waiting 2 weeks for Kodak's lab to process it. Oh wait! You can't actually buy K25 anymore can you? So where is this mythical alternative that you're comparing the D700 to? Please don't invent non-existent problems just for something to whinge about.</p>

[carl_becker2]

<p>Thanks for the wonderful info. As I said I do enjoy my D700. Not perfect but I think it will satisfy most of my needs for years to come.</p>