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"APS-C sized" four/thirds ratio sensors

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lutz

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Would it theoretically be possible for Pentax to use roughly "APS-C sized" four/thirds ratio sensors in the future models? Meaning, they could increase the sensor area for a better signal to noise ratio (height only) and should eventually still be able to use the "digital-only" lenses and their image stabilization system.

I do find the four/thirds aspect ratio (as in standard digicams) more useful than the two/thirds used by anybody else than Olympus (the latter with a far smaller sensor however).

This would require Pentax to have access to custom made sensors. etc.... but I am pretty sure they would have reservations against Sony in the long run anyhow.
 
Well, the sensor area would grow, giving you more freedom to crop, while providing "higher quality" for all images that do not need cropping.
 
I thought you meant you wanted APS-C sized (hence the same area of an APS-C sensor) but only in 4:3 format. The area is the same - IQ won't improve but I see you're saying you want the long side to be the same as the long side on the 3:2 APS-C sensor - for simplicity lets just say it is 24 x 16. Then the 4/3 will simply be 24 x 18 - hardly a differnece to have a noticeable impact on IQ and it may still cause problems with vignetting on lenses. I'd then prefer a 28 x 18.66 (3:2) APS-H anyways :)
lutz said:
Well, the sensor area would grow, giving you more freedom to crop,
while providing "higher quality" for all images that do not need
cropping.
Click to expand...
--
Sinan
http://sinantarlan.zenfolio.com/

 
lutz said:
Would it theoretically be possible for Pentax to use roughly "APS-C
sized" four/thirds ratio sensors in the future models? Meaning, they
could increase the sensor area for a better signal to noise ratio
(height only) and should eventually still be able to use the
"digital-only" lenses and their image stabilization system.

I do find the four/thirds aspect ratio (as in standard digicams) more
useful than the two/thirds used by anybody else than Olympus (the
latter with a far smaller sensor however).
This would require Pentax to have access to custom made sensors.
etc.... but I am pretty sure they would have reservations against
Sony in the long run anyhow.
Click to expand...
Cost is probably the biggest obstacle to custom sensors. Most DSLR cameras use readily available off the shelf parts, including sensors. So a specially made sensor can be prohibitively expensive and also risky because it is not known how potential customers will react to it.

But it is nevertheless an intriguing idea. Most sensor makers still copy the 1:1.5 ratio slavishly. There may be room for experimentation in the future but again cost could become a constraint because custom shutter and mirror boxes must be built to accommodate oddly shaped full size sensors. For now, the obvious upgrade path is to full frame (24x36mm), rather than to unconventional sensors with different aspect ratios that are less than full frame in size.
 
If my rusty math is not betraying me, an APS sensor pushed to four thirds ratio would have 11% more surface and similarly 11% more megapixels, which might be good for marketing purposes.
(APS-C: 25.1*16.7 = 419.2 mm2 ; APS 4/3rds: 25.1*18.83=472.5 mm2 ).

I blieveve this could be very usable real-estate which should be in line with the current lens designs.
 
The 3:4 image ratio is my preference as well as it suits my preferred 11x14 and 16x20 inch print formats much more closely than 2:3, where I'm essentially turning the K10D 10Mpixel camera into a 7.2 Mpixel camera by cropping.

I use 4/3 System gear as well as Pentax and find the imaging quality based on noise and pixelation is identical to what I get from the K10D in the ISO 100-400 range. The 4/3 System sensor isn't "far smaller": it's 86% of the K10D sensor's vertical dimension and 76% of the K10D sensor's horizontal dimension, the latter due to its different proportion to a great degree. My camera is the Panny L1 which means that it has about the same pixel resolution as the cropped K10D images and gives up something around 1 stop on sensitivity/noise characteristics. These differences come into play at ISO 800 and particularly 1600 where the K10D is significantly quieter, but the L1's sensor is now two generations behind current Panasonic's latest 4/3 System 10Mpixel sensors, which are quieter and pose an nice gain in resolution.

How feasible it would be to build a 3:4 ratio sensor in a larger scale for Pentax cameras is intriguing and depends upon how much effort Pentax wanted to put into the effort. First a supply of sensors would have to be obtained ... extending the dimensions in either vertical or horizontal dimension requires changes to focusing screen, prism and viewfinder optics, mirrorbox and mirror, shutter, etc, so this is no simple or inexpensive development project. Switching to 4/3 System would raise a hellacious hue and cry. Just cutting the present sensor down to 3:4 proportion has no real value but would save money on changes for all these other things.

What makes sense given the image circles of their current lens line would be an 18x24 sized sensor. That adds about 12.5% more pixels ... the K10D becomes a K12D ... at the same photosite density. That nets me greater resolution, would work with current lenses, etc etc.

But I wouldn't hold my breath expecting it to happen. ;-)

Godfrey
 
12.5% more sounds even better. There is certainly nothing sacred about the present aspect ratio. If some other sensor manufacturers could get into the DSLR game we would likely see more different approaches - Sanyo, Fuji, Samsung Cypress ?

For the vast majority of my images (other than landscapes) a 4:3 ratio seems to be certainly the less wasteful design.
 
I prefer 3:2 format, it is nearest to the ISO paper sizes which are in common usage here in Europe.

If you wish to have precisely the same vignetting amounts, the larger you go in one direction, the smaller you have to go in the other if you wish to stay within the existing image circle size, so the net gain in MP's is almost zero.

More on aspect ratios:
http://en.wikipedia.org/wiki/Aspect_ratio_%28image%29

You will see that there is a plethora of different formats that have been used and are still in use.

Also look at the so called "Golden Ratio" rule, widescreen monitors are the closest to this at a 1:1.6 ratio:
http://en.wikipedia.org/wiki/Golden_ratio

Basically it's - "May your God go with you"!

As far as Pentax making a new size sensor with a 4/3 ratio of marginal increase in size, I cannot see that ever happening. I think that for the K mount they will stay with 3:2 even if they do ever decide to go for a larger sensor (1.3 or larger). The only 4/3 format ratio they have ever considered is the postponed 645D project, even so the sensor is smaller than the original film size by a 1.3 crop factor.
--
Richard Day - 'Carpe Diem!'
Gloucester UK
 
In North America we do things differently. Our paper and print sizes are different from the rest of the world. I personally like 3:2 prints. I have been doing this since 135, and now with APS-C. One thing I don't like about compacts is their 4:3 ratio which I ended up cropping, and something impossible due to composition. With 3:2 I can compose as tight as I want.
--
Alan Chan
http://www.pbase.com/wlachan
 
All the talk in recent days of potential sensor developments has me beginning to question ordering my 16-50/2.8 DA*. My hypothetical questions include:

Is this lens going to be limited to current models?

If the sensor ratio is changed will it increase in size beyond full effective use of the current digital only lenses?

I had no idea that certain trends were leading towards FF sensors. I thought the current sensor sizes and ratios were what was desired.

I received a real revelation from this post today as I've only ever shot my digicam and from that assumed all digital cameras were 4:3. A few years ago the rookie in me thought, "It makes such a perfect standard monitor background."

Oh what I have learned from my reading of this forum.

Personally, I hope that if there is a change it will not be to the degree that any current lenses become obsolete. As was mentioned previously, I find it hard to see Pentax straying toward anything that might jeopardize use of the K mount. That was a significant factor in helping me choose my near future purchase of the K10D.

--

When terrain won't accommodate my wheelchair I am reminded of my appreciation of telephoto lenses.

http://www.jaysspace.com/photography/
 
John Bean (UK) said:
Sinan Tarlan said:
Not to mention that it will be hard to get sensors other than from
Olympus I guess.
Click to expand...
Olympus don't make sensors, they buy them from Kodak and Panasonic.
Click to expand...
You're right I actually even knew Panasonic made the sensors - don't know why I blundered there. They even make them for their own compacts too - can you tell I'm just showing off now :) In fact the sensor company I think is even called something else like Matsutisha or something like that - I believe it's the parent company (can you tell I'm still trying to show off? :) )

Didn't know about Kodak though! :)

--
Sinan
http://sinantarlan.zenfolio.com/

 
Sinan Tarlan said:
You're right I actually even knew Panasonic made the sensors [...]
Click to expand...
SFT007 said:
Didn't know about Kodak though! :)
Click to expand...
The very first 4/3 camera (the E-1) had a Kodak "Full Frame Transfer" CCD, and several other models as recently as the E-400 had other Kodak sensors. Current models all use Panasonic though, probably as a result of the technology exchanges that gave birth to the Panasonic L1.

Interestingly Leica uses in its M8 a larger 3:2 Kodak CCD that's a direct technological descendant of the original E-1 sensor; the FFT technology has some definite advantages, not the least of which is lack of banding.

--
John Bean [BST/GMT+1] ('British Stupid Time')

PAW 2007 Week 42:
http://waterfoot.smugmug.com/gallery/2321711/#210592560-XL-LB



Index page: http://waterfoot.smugmug.com
Latest walkabout (30 July 2007):
http://waterfoot.smugmug.com/gallery/3247039
 
luc0815 said:
If my rusty math is not betraying me, an APS sensor pushed to four
thirds ratio would have 11% more surface and similarly 11% more
megapixels, which might be good for marketing purposes.
(APS-C: 25.1*16.7 = 419.2 mm2 ; APS 4/3rds: 25.1*18.83=472.5 mm2 ).
Click to expand...
You're off a little. Remember, you can't have a longer diagonal, so if you increase the size on one side, you need to decrease a bit on the other to keep the diagonal the same.

And when you do that, you get about 24.1*18.1=436.3 mm2, or a difference of 4%. Not a whole lot to argue about.

--
Japan: http://www.lucs.lu.se/people/jan.moren/log/current.html
Images: http://www.flickr.com/photos/jannem/
 
Jay,

APS-C (or something very similar) is here to stay for the forseeable future. I see no reason to worry. Perhaps Pentax could offer a full-frame flagship model - and lots of people here are hoping for it - but it seems quite unlikely. All cameras are going to improve FF as well as APS.
 
Hi Richard,

I'm very to square and near square compositions. Independent of paper wastage, the neat thing about 3:4 ratio is that you can crop to square or 2:3 with less average pixel wastage than if the capture is 2:3 and you need to crop to 3:4 and especially square.

Godfrey
richardday said:
I prefer 3:2 format, it is nearest to the ISO paper sizes which are
in common usage here in Europe.

If you wish to have precisely the same vignetting amounts, the larger
you go in one direction, the smaller you have to go in the other if
you wish to stay within the existing image circle size, so the net
gain in MP's is almost zero.

More on aspect ratios:
http://en.wikipedia.org/wiki/Aspect_ratio_%28image%29

You will see that there is a plethora of different formats that have
been used and are still in use.

Also look at the so called "Golden Ratio" rule, widescreen monitors
are the closest to this at a 1:1.6 ratio:
http://en.wikipedia.org/wiki/Golden_ratio

Basically it's - "May your God go with you"!

As far as Pentax making a new size sensor with a 4/3 ratio of
marginal increase in size, I cannot see that ever happening. I think
that for the K mount they will stay with 3:2 even if they do ever
decide to go for a larger sensor (1.3 or larger). The only 4/3 format
ratio they have ever considered is the postponed 645D project, even
so the sensor is smaller than the original film size by a 1.3 crop
factor.
--
Richard Day - 'Carpe Diem!'
Gloucester UK
Click to expand...
 
By the time Pentax comes up with a camera with an alternative sensor format, they'll have a plan for how it will be able to make use of all the lenses they've spent several hundred million dollars developing for the past several years. ;-)

Godfrey
 
Thanks for the correction and explanation!

( I told you my math was rusty).
 
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