Sensor Density...How dense can we go?

In view of some of the higher density sensors appearing elsewhere, I wondered in relation to Pentax how the technology has developed in relation to pixel density over the years. Taking sensor size in mms to work out the area of sensor in centimetres squared, then using this figure to divide into the effective megapixel size of sensor produces the following pixel densities measured in Megapixels per centimetre squared:

istD 1.66 (MP/cm squared)

K10D 2.72

K-m 2.77

K-x 3.32

K-7 4.0

K-5 4.39

K-S1 5.5

K-70 6.63

K-3 6.66

K-1 (Full Frame) 4.24

645D (Medium Format) 2.75

645Z 3.53

Looking at these figures, if people are happy with image quality of K-3 / K-70/ / KP then plenty of room for increase in Pixel density of both FF and MF.

Hang On!!!.... Hang On!!!.... Hang On!!!.... Not so fast Pentax have promised a new camera for 1980 and the first thing you complain about is megapickle density

--

I don't see the need for sensors with more MP or pixel density than what we have already. I can print 24" x 16" from my K1 with excellent results.

I'm not necessarily advocating that we need more pixel density...I personally like the 'look' of the relatively low density K-x and now K-50 sensors and the IQ and 'feel' of the 645D is i'm guessing largely due to its low pixel density. However...competitive pressure may cause Ricoh to increase the pixel density on their new APS-C flag and the other two formats (more so MF than FF) will likely be under similar pressure...possibly be a new MF announced soon to 'keep up with the Jones' ?

I dont see how Pentax can be pressured into anything regarding sensors.

They don't make them and do not have the financial clout to tell a manufacturer to produce one to their spec. They will use what is available.

I've had someone print a 24x16 from a cropped Pentax Q shot. They were quite happy with the result.
Bear in mind that lower pixel density means less noise in the final result which is why FF and MF don't require it increasing, it's really good as it is.

Also, bear in mind that the larger the print, the further away viewers are going to be standing from the image. This, in itself negates the effect of print quality...
Yes, we see the difference as we zoom in... but the print result will not reflect that... all printers vary if you are home producing... commercially, you are in the hands of their technicians and what they want as turnover!
I can view a 20"x10" picture on this monitor... and I have found that viewers are very happy with what they see on screen... and from my 6 colour printer....
even when printed commercially they are happy with the result... (my pictures are all Natural History focused)...
incidentally people seem to prefer mat finish over gloss.... and silk seems a good middle of the road for displays...
BUT...
I have yet to see anyone take a magnifying glass to one of my prints to see if there are any dead pixels visible.

I honestly do not think that pixel density is as important as overall picture quality...
and my K-3ii seems to require more work on a picture than for the K-1ii...
just my ha'peth worth...

There are other factors at play here. One is sensor type (CCD, back side illuminated, Foveon, and probably others that I am unaware of), another is advances in manufacturing technology and the inventiveness of engineers. Interestingly CCD - which is old tec, noisy, and limited in functionality - is yet frequently cited as superior in image quality for colour rendition. Personally I have very limited understanding of these things, but there are so many other issues at stake which are relevant to picture quality.

Back on the topic of sensor density:

At any given point in time, is there an inverse relationship between pixel density and dynamic range?

Anyhow, if all things were equal, the main advantage for me in higher pixel count is the potential it offers for more extreme cropping.

It appears purely because they can fit it easily on a tick list. If Pentax still used CCD it would be listed as a Negative.

No one's ever posted any proof or a macro that converts one to the other

as a video shooter I can attest that the image quality when you crop in from FF to APS-c on the a7III or the extended zoom function (same thing) on the NX80 there's no loss in quality... I have a custom button set up on my a7III to "zoom in" instantly.... when needed... on event shoots this means my 16-35 is the only lens I need...
I think it would be a great feature for stills photographers to have a custom function you set up just like bracketing focus and bracketing EV if you could have the camera "bracket" your cropping based the af sensors... nature and sports photographers would save some time in post that way.

I'm pretty sure you can do that.