My default companion since 2004 has been the superb Canon 1D Mk II. Although it is a bit heavy, it fits my quite large hands perfectly and its weight balances nicely to larger EF lenses. I am overall very satisfied with the picture quality and its snappiness is amazing and I cannot really say that I have ever missed a shot because of the camera. The very tough body and its weather sealing surely works - from rain to condensing humidity, cold, dust and dirt and hard bumps - the MkII has never betrayed me. Together with numerous expeditions with my Land Rover Defender, I has taken some real hits over the years and there are quite a few "scars of action"...

I have always been dreaming of a full-frame body, but the shocking pricing of the 1Ds line has made me think that there is no real difference between the 8.2M pixels in the 1DmkII and the 16.7M pixels in the 1DsmkII :)

With the introduction of the full-frame EOS 5D a full frame body suddenly become affordable. I tried one and filled up a 1GB memory card. It surely delivers very clean images and the noise levels at high ISO settings are impressing. The large LCD is also nice (but since it does not affect the picture quality, I don't really care)

However, I have been a bit reluctant in getting one. For some reason I don't really think it is good value for that money. Also, my 1DmkII has taken lots of hits, water and dirt out in the field and I think the 5D is more of a town/indoor camera.

Since the introduction of the EOS 5D it seems like the price of the older (introduced in 2002) 1Ds (- Mark I) has dropped significantly. Given the same ergonomics and battery, I decided to go that path instead. I recently got a mint 1Ds with just some 8000 shots on the meter for about 2/3 of the price of a new 5D.

My conclusions after a few weeks are:

a) The pictures from the 1Ds are razor sharp (sometimes almost painfully sharp) out of the camera. The level of detail is amazing. So far, I have not seen any signs of Moiré.
b) The noise performance up to ISO 400 is to what I can see almost identical with the MkII.
c) The noise of the 1Ds reminds me of my ISO400 Tri-X shots from the early 1980's, i.e. "good looking nose" to some extent.
d) However, the SHADOW noise is very pronounced on the 1Ds
e) The shadow noise has a slightly different and more pronounced characteristic compared with the MkII
f) Who turned on the light? Although the shift from a 10D to the 1DmkII was amazing in terms of viewfinder brightness, hey - this is something spectacular.
g) The default 1Ds profiles in C1 are crap - replace with the ETC ones. However, I can see a bit of a greenish cast in low-light indoor shots which I'm not perfectly pleased with.
h) Switching between these bodies is a non-issue since the handling is almost identical
i) The CF performance of the 1Ds reminds me of my earlier 10D. To write a 10MB RAW file it takes about five seconds. It is no real pain, except when you like to make a test shot to check the exposure prior to the real shot - the cycle is a bit too long. Reviewing is also very slow.
j) The battery performance seems to be about 20% or so compared with the MkII at low temperatures (big issue here in Sweden). After some 100 shots at -5 degrees C the battery low started to flash (i.e. empty!). It seems better at room temperature - I guess that some 200-300 shots can be expected from a fully charged battery. My 1DmkII does at least > 400 at low temperatures and > 600 at room tempeature.
k) The flash exposure metering is not that accurate. It seems like there is somewhere 1/2 - 1 steps of constant underexposure although it overexposures heavily sometimes.
l) The LCD technology has developed considerably since 2002. Well, let's say that a detailed explanation is superfluous...

In summary - Although we're talking about a guy who is four years behind state-of-the-art, I think the original 1Ds is a bargain and gives excellent value for money, at least in comparison with the 5D (and the ridiculously expensive 1Ds Mk II). I am sure Canon is going to give us something that will fill the gap between the 5D and the 1Ds Mk II in a near future, but I think I'm fine with my current arsenal for the time being.

I''ll add some samples as time goes by and (if?) something significant has been discovered.
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