Thread: Pentax 645D leaked!

nice and sealed and I like that catch.

Notice the tripod socket on the side? Pretty slick.

Few more tidbits from a Japanese photo site...

-Sensor is equivalent to 170% of the area of a 35mm full frame sensor

-Dual SDHC slots, writing to both cards at the same time or sequentially

Originally Posted by _L_U_C_A_

SDHC

good thing the image from the last page shows one CF and one SD slot though.

Could have been a prototype perhaps? But yeah, it would be better.

Pentax Japan is showing more of it now on the countdown page and the time bar is 3/4's of the way to launch.

Originally Posted by jacobsen1

nice and sealed and I like that catch.

Notice the tripod socket on the side? Pretty slick.

I think Pentax 645's have always had that side socket. I wish they could do that with their smaller bodies.

http://www.1001noisycameras.com/2010...egapixels.html

Now back to the more serious topics - although at one point the 645D was a "$5 task" ;-) Pentax Japan has updated their 645D teaser (memo to Pentax-Japan: please create text-based teasers so we can computer-translate), and DC Watch Impress human-translates it. The new revelation is that the camera will have a 40-megapixel sensor, but they do not reveal the type of sensor (CCD? CMOS? other?) or maker (via Foto Actualidad)

Interesting...

http://thephoblographer.com/2010/03/...ds-new-sensor/

sounds a lot like that new $20k mamiya back...

I can't remember if it's already been mentioned in this thread, but the price was announced today, and it's ~$9,400 equivalent in Japan... wonder how that will translate here (probably not favorably).

Photo gear in Japan is typically priced alot higher than it is in the US. I could still see it going for $6500-7000 here....

Originally Posted by _L_U_C_A_

Photo gear in Japan is typically priced alot higher than it is in the US. I could still see it going for $6500-7000 here....

That's what I'm hoping, but this is a niche product and the yen is still pretty strong.

Its here!

http://www.dpreview.com/news/1003/10...pentax645d.asp

Originally Posted by _L_U_C_A_

Its here!

http://www.dpreview.com/news/1003/10...pentax645d.asp

Thanks... that's actually what I was referring to, I just forgot to post the link...

Originally Posted by Markitos

Thanks... that's actually what I was referring to, I just forgot to post the link...

Ah!

dual SDs for sure.

but damn, if this thing is sub $10k, that's a hell of a price point to hit. Less than half than new mamiya...

If it's really under $10k, it has potential to be a pretty epic camera, IMO--it will finally break the barrier for a lot of people... choosing between a 1DsmkII or D3x and a $30k Phase One MF system is one thing, choosing between one of those and a 40mp, $7k body is another thing altogether.

If they didn't **** up (and Pentax usually makes good stuff), this could be a gamechanger (IMHO, of course).

^ yeah, it's basically the drebel of DSLRs or the 5D of FF DSLRs.... Could be amazing and I don't double the IQ will be amazing at lower ISOs. Pentax isn't bad at higher ISOs either, but that's just not the point of this camera.

Anyway, some math:
APS-C sensor = 22.3mm x 14.9mm diagonal 26.82mm
FF 35mm sensor = 36mm x 24mm diagonal 43.27mm
645D sensor = 44mm x 33mm diagonal 55mm
645 film = 60mm x 45mm diagonal 75mm

43.27/ 26.82 = 1.6 for the "crop factor" of APS-C to FF.
43.27/55 = .787 for the factor for the 645D
43.27/75 = .577 for the factor for 645 film.

A 35mm lens is the widest lens available for 645 systems right now, pentax happens to make one. So 35mm * .787 is 27.5mm.
That same 35mm lens on a film 645 body is ~20mm...

So yeah, they're going to need to make some wide lenses for this thing to make it work. If it'd been a "FF" 645 sensor it could be OK with a ~20mm wide angle, but for me at least having a 27.5mm focal length as the widest non fish option won't work. I wonder how long it'll take them to make something wider.

as for pixels/area:
FF 35mm sensor = 36mm x 24mm = 8.64cm²
645D sensor = 44mm x 33mm = 14.52cm²

the 5D/D700 have ~1.45 MP/cm²
the 5Dii has 2.43 MP/cm²
the 645D has 2.75MP/cm²
the D3x has 2.89MP/cm²

so while this sensor is big, it's still got a LOT of pixels shoehorned onto it. The cameras above were picked because they're high MP high IQ FF sensors of their day at least.

And here's a link to the spec sheet for the sensor, for anyone who's interested (I'm looking at you, Porter)
http://www.kodak.com/global/plugins/...00LongSpec.pdf

I'm concerned that the saturation signal is a mere 42K e-. Great quantum efficiency though.

why would the point at which the sensor saturates, in and of itself, be an issue?

Originally Posted by ride5000

why would the point at which the sensor saturates, in and of itself, be an issue?

The full-well depth (aka full-well capacity, aka saturation point) describes the number of electrons that a single pixel can hold. Since electrons are generated by incoming photons, it describes the maximum signal level that you can capture, and therefore the dynamic range (to some extent). It can hold a theoretical maximum of 15.4 bits of information per pixel, but since nobody uses a 1:1 mapping for electrons to digital counts (it's usually between 2-4 electrons per DN), it only needs about 14 bits to fully describe the range of the sensor, which is coincidentally what they're using for their A/D converter. The best digital backs out there use 16-bit converters, and actually offer a range to match.

At the other extreme, point and shoots (and to an even greater extent, camera phones) have very low saturation points, which is why they clip highlights so quickly. You want some headroom for different lighting conditions, dynamic range, etc.

so how does this sensor compare to some of the FF 35mm sensors that are highly regarded then? (5D, 5Dii, D700, 1Dsiii, D3s/x)

Originally Posted by jacobsen1

so how does this sensor compare to some of the FF 35mm sensors that are highly regarded then? (5D, 5Dii, D700, 1Dsiii, D3s/x)

The pixels are in between the 5Dii and D3x in size, so... probably about the same as them. And that's good enough for most people.

Originally Posted by jacobsen1

but damn, if this thing is sub $10k, that's a hell of a price point to hit. Less than half than new mamiya...

Too bad you won't be able to buy it in the US, I suppose.

Originally Posted by Kilonad

The full-well depth (aka full-well capacity, aka saturation point) describes the number of electrons that a single pixel can hold. Since electrons are generated by incoming photons, it describes the maximum signal level that you can capture, and therefore the dynamic range (to some extent)..

as you hint, DR is a multi-faceted metric. i wouldn't automatically assume that the DR will suffer from a low(er) saturation point.

Originally Posted by ride5000

as you hint, DR is a multi-faceted metric. i wouldn't automatically assume that the DR will suffer from a low(er) saturation point.

It's multi-faceted in the sense that it's dependent on maximum signal level, and what the noise is. Dynamic range goes hand in hand with peak signal to noise. So yes, it will automatically suffer from a lower saturation point. The KAF-39000 has larger pixels, a higher saturation point (60K e-), and a higher read noise (16 e- vs. 13 e-). However, its linear dynamic range is 71.4dB, slightly more than the 70.2dB of the KAF-40000 used in the 645D (6dB = 1 stop). No idea what it is for the D3x or 5Dii chips, simply because neither Canon nor Sony have any interest in marketing their sensors to the general scientific community.

Originally Posted by Kilonad

It's multi-faceted in the sense that it's dependent on maximum signal level, and what the noise is. Dynamic range goes hand in hand with peak signal to noise. So yes, it will automatically suffer from a lower saturation point all else being equal. The KAF-39000 has larger pixels, a higher saturation point (60K e-), and a higher read noise (16 e- vs. 13 e-). However, its linear dynamic range is 71.4dB, slightly more than the 70.2dB of the KAF-40000 used in the 645D (6dB = 1 stop). No idea what it is for the D3x or 5Dii chips, simply because neither Canon nor Sony have any interest in marketing their sensors to the general scientific community.

fixed

Originally Posted by Idjiit

Too bad you won't be able to buy it in the US, I suppose.

yeah, you really think they won't bring it here?

http://www.bjp-online.com/british-jo...er-645d-camera
http://en.akihabaranews.com/49635/re...hooting-photos
http://www.ephotozine.com/article/Pe...=Google+Reader

Well if it actually performs how they say and the prices are around what they say, then I figure it will give the competition a run for its money. At that price my grandfather might have bought that instead of his 1Ds MKiii, that is if it was out when He bought it. He moved from a medium format film Mamyia.