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07-19-2014, 06:58 AM   #166
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QuoteOriginally posted by Sandy Hancock Quote
Forgive me if this has been mentioned before, or if my assumptions are incorrect due to my freely admitted limited knowledge of optics, electronics or business.

Square format.


1) If I have done the geometry calculations correctly, the same sensor area as a 36x24 rectangle is a 29.4mm square, but the maximum square that will fit in the "full frame image circle" is 30.6x30.6. That would give the sensor 0.6mm of wriggle room in each direction for shake reduction without impinging on the edges of the image. I confess I do not know whether that is enough, but it might go close without resorting to APS-H.

2) You would never have to rotate the camera to portrait orientation, so there would be no need for a portrait grip, an on-camera flash would always be where you want it to be, one tripod mount will always be enough.

3) It would fulfil the stated need for a Pentax FF to be something genuinely unique in the market.

It would have to be mirrorless though, as the K-mount registration distance will not accommodate a 42mm deep mirror. So a killer EVF and tilting LCD would be essential.

If the sensor could be cut from the same wafers as the 645z it would be about 30 megapixels and would presumably be capable of similar dynamic range and high ISO performance, which would make it a very competitive offering.

We did discuss this some years a time we thougt that the FF was coming soon...........

Yes this sensor could be great and is larger in every aspect then APS-C and even APS-H. Still this is not the biggest sensor that could fit in. Problem is that sensors are expensive, but who knows what is possible. If the sensor is bigger then the 30x30mm one could use the part that is needed.

So how big should the sensor be?
Considering the most options that can be used for a modern camera. I know we do cut eveything to our likings in photoshop, but some formats are most popular:
  • 1:1 ratio square
  • 3:2 ratio
  • 4:3 ratio
  • 4:5 ratio
  • 16:9 ratio (screen stills and video)
  • 16:10 ratio (screen stills)
  • movieformat widescreen 2,37:1 (2560x1080), mostly video
  • 2:1 ratio for still and 4k video.
  • 3:1 ratio for panoramic stills
  • 4:1 ratio for panoramic stills

So for all these formats one could find the optimal size of the sensor. To get the most megapixels in use all the time. And to at least put in the smallest possible sensor, since that does adds cost to the camera.

For instands for panoramic's one could use the 3:1 ratio out of the sensor. So then you would use 40x13,33mm of the sensor (probably working in liveview). Still having 19 megapixel to work with and a huge angle. For 4:1 ratio one could even go to 42x10.5mm, but then you add size to the sensor that is mostly never used.

Look at it like building a stadium for soccer. We are planning a new National Stadium overhere in Rotterdam where Feijenoord is playing as home team and later also our National soccer team. So the current stadium fits 50.000 people and the new stadium should fit 70.000 people. The question is how often those extra 20.000 seats will be filled. Or maybe a stadium with 60.000 seats would be more benefitial? For the home playing team the extra seatings, or the need for more then 60.000 seats is only 3 times a year. For our national team only for the big qualifying games for World Cup or European Cup would need those extra seatings, filling the 70.000 seats maybe 2-3 times a year. Then there are concerts, but those also would attract the 80.000 - 90.000 visitors just maybe one or two in a seazon (90.000 for a round podium in the middle of the field and 10.000 standings on the field). So economical the stadium should grow to 60.000, but it's soccer, so the law's are diferent and we build the grant stadium.

So since the panoramic ratio makes the width of the sensor, how heigh should it be? Probably is using the camera tilted is one way to save sensorsize. Probably cheaper then making a 40x40mm sensor, wich would even be larger then the sensor inside the 645Z. Maybe why the sensor in the 645Z is 44x33 and not grown to 48x36mm.

For 4:3 the max height of the sensor could be 26mm, tilting the camera giving the maximum space o the sensor. For 4:5 one could use a little more. For square ofcourse your 30x30mm size. The video (screen) formats 16:9, 16:10 and 2,37:1 can't use the whole width of 40mm, but would stop at 38mm or so.

A sensor at the size of 38x26mm is probably economical the max to use. Being a little optimistic one could also go to 40x28mm and put the camera in the market for panoramic and landscape use. Or 36x30 offering the square version, next to being versatile with other formats..

Last edited by RonHendriks1966; 07-19-2014 at 07:28 AM.
07-19-2014, 08:06 AM   #167
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Just thought of it, but no idea if it works, but I guess it can. The camera with K-mount and 38x26mm sensor has 35 megapixels. Those are used in different sections, depending on the ratio aspect chosen.

One great kitlens to it, 25-100mm/f4 that can cover the whole sensor and it's 35 mp. Not to fast, but this could work from a technical point I think. A single lens to use the whole sensor.
07-19-2014, 11:30 AM   #168
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The ability to choose either shutter count or FPS as a priority(11fps for sports for instance).
07-22-2014, 05:42 AM   #169
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not sure if said, but the ability to set a minimum shutter speed. Kind of like auto iso where you can set the min and Max.


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