By no means complete in all minute details of differences and similarities, the intention here is to compare only the most relevant features. Features which in my view show the amazing evolution of Nikon's digital SLRs development. Those which do make a significant difference from the perspective of the user.
My very personal conclusion is that the D70 is a fantastic camera and, before the D2X is in the stores shelves, Nikon's best. The Nikon D100 is an excellent camera that can deliver amazing photos; but a camera superseded by the D70 in almost every aspect. If you don't absolutely need the vertical grip capability, get the D70. The D1H is also a fantastic camera, built strong as a tank and lightning fast. Surpassed in certain areas, nevertheless still amongst the best in the world for sports photography. I've concluded that if I could have most of the D70 on a D1H body I would be a most happy man ;-)
Yeah, but one could ask "What about the D2H?" Well, it is not in this comparison for two reasons. First, the D2H is at another price range, despite it's dramatic price drop in the USA. Second, I have not used the D2H enough to feel qualified to judge it. I have closely followed the knowledgeable debate about this camera at nikonians.org to know that a D2Hs will soon follow. Evidently, the D2X can't be by itself in the top range of pro DSLRs in Nikon's product strategy.
Nikon D1H - 2001
With 2.7 effective megapixels; S, C, and M shooting modes, the D1H gives us 5 frames per second and up to 40 consecutive shots in a rugged F5-like body. Flash synchronizes up to 1/500 of a second.
When it came to market it was around 3,100 USD. Today can be found used, in excellent plus condition, for about 1,300 USD.
Nikon D100 - 2002
The D100, with 6.1 effective megapixels, allows for 3 frames per second bursts into a 6 frames buffer, in a F100-like chassis. D-TTL flash synchronizes up to 1/180 of a second.
Back in 2003, its price was 1,500 USD. Curently can be still be found brand new for 1,200 USD, 1,000 USD after rebate in the USA.
Nikon D70 - 2004
Then comes the D70, with the same 6.1 effective megapixel rating as the D100. Built over a F/N80-like chassis allows 3 frames per second and a 12 frames dynamic buffer that lets you capture up to 144 pictures in sequence with no buffer stall using selected CF cards. i-TTL Flash synchronizes up to 1/500 of a second, as the D1H.
Current price in the US is 1,000 USD.
In many areas the three cameras performances compare, but it is important to take into account the difference made by their specific positioning in Nikon's product segment strategy. Also, one should remember that there are digital light years of technological advancement in between each of them. The Nikon D70 is, for example, way ahead in some areas, even though the least expensive model, simply because it is the newest member of the family and takes advantage of such developments.
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