Just Wondering

[peterottaway]

Had a look at the first publicity photos of the just announced Nikon D7000 with its ( not a ) Sony 16.2 MP sensor.

In specification it has moved up half a class or so, what does this imply for any successor to the Nikon D300s ? At USD 1200 I would think it difficult to market a D300s replacement at about USD 1700-1800 with just a tweek here and a minor modification there even if they did up its video performance as well. In fact it is almost a Nikon version of what the Sony A700 replacement was expected/hoped to be before the A33/A55 set people speculating again.

So is there going to be an APS sensor replacement for the D300s or just D700 FF successor(s) in the mid level price range ? The D7000 with 6 fps, 1/8000 th shutter speed, alloy body and a genuine pentaprism viewfinder, appears to be all that a traditionally minded enthusiast stills photographer would want. And it is considerably cheaper than the older (!) Canon 7D and much better than the Canon 60D.

[KevinBarrett]

The D300s still has more AF points and faster burst rates, so there's that. It's good to see some serious unrelenting pro-spec-bang-for-your-buck pressure on Sony, though. I like the big pentaprism viewfinder and the sync speed (up to 1/320, by some Nikon magic), two of the most important factors for getting my attention. You're right, though: if this isn't the replacement for the D300S, then that camera will be positively spectacular.

Sony? Care to respond?

[David Kilpatrick]

1/320s sync is not Nikon magic. If 1/200th sync was possible on a full frame camera (which is generally is with a 1/8000th speed shutter) then 1/320th has always been a likely figure for DX. The shutter is that much smaller. What is harder to explain is why most digital models have had such leisurely sync speeds.

There are two ways of getting 1/8000th. First: shutter is fully open at the highest sync speed. Say this is 1/250th. Slit is half-height at 1/500th, quarter at 1/1000th, eighth at 1/2000th, sixteenth at 1/4000th, one-thirty-second of the image height at 1/8000th.

With an image height of 16mm (shutter gate) that means 0.5mm shutter slit. To maintain even exposure, this 0.5mm slit needs to be designed to remain a virtual 0.5mm from top to bottom of the frame despite the offset of the two shutter curtains. That is achieved in practice by changing its width as the slit moves. It also needs to be very parallel and very 'smooth' to avoid uneven exposure, and because it is only 0.5mm, it tends to introduce diffraction which reduces sharpness.

Now if you can speed the shutter up so that 1/320th is the 'fully open' time, the slit at 1/8000th becomes a little bit wider and all the tolerances are improved - the curtains/blades are moving faster, but the rest of engineering becomes simpler.

David

[Javelin]

thats a very good explanation and shows how importat max shutter speeds can be if the manufacturer takes advantage of it for sync speed.

[KevinBarrett]

I mention the "Nikon magic" because both the D7000 and D300S list max sync speed at 1/250, then add some little parenthetical scenario in which sync speeds reach 1/320, "reduced GN" or "Auto FP." I don't know what those terms mean, kinda like I don't know what the term "servo" means, or why it continually shows up in various AF modes.

[David Kilpatrick]

Just means the flash duration is being curtailed a little by 1/320th. Not sure why. Minolta was able to achieve 1/300th on full frame but only with a 1/12,000th speeded shutter. I doubt they are electronically gating the exposure, which they could do on the D70 to 1/500th.

David

[Greg Beetham]

i'm sortof getting the impression it's a long duration flash pulse to get full coverage of the frame as the shutter is not actually fully open at that 1/320sec speed at any one time, hence the lower GN to account for the power diversion...sortof like HSS flash with it's much lower GN figures...maybe.
Greg

[bfitzgerald]

Leaving aside any tech talk on flash...

I think Nikon have hit the spot nicely with this one (and leaves the door open for an updated D5000 model as well)
I see that a Canon 60d has dropped to £899 body only on camera price buster! Must have shaken them up a little I think.

Question is when will Sony respond? Or will they be able to offer something similar to Nikon. Make no mistake the D7000 is going to be a huge seller for Nikon. There are not many holes to pick in this one not really.

[peterottaway]

Well the last Canon I actually bought was the T90, so I may be regarded as being a bit negative towards Canon. But the 60D to me seems to be more of an improved 550D rather than a genuine 50D replacement. However, having gone straight to a decent discount then there will be some happy buyers amongst the Canon crowd.

[Greg Beetham]

I don't really see the point of the 50D,60D model here any more now that Canon has introduced the 7D, (and I guess there will at some point be a 7D MkII), but on looking at the price it's a little odd really, here there is only about $300 difference between a 60D and a 7D, (probably the difference between new and old http://www.cameraaction.com.au/call1300 ... sp?dept=18), but I see on dpr there is about $1000 US difference in the street price...but shopping around it looks like you could get the difference down too about $500 US, so maybe there is a point to the 60D after all....in that market anyway.
Greg