Re: Who only 16k for a camera sensor
Brisn5757 wrote:
aliasfox wrote:
I wouldn't say 16MP is enough, but if you're shooting/framing reasonably, it likely isn't the limiting factor.
As others have mentioned, 16MP is more than enough for most viewing scenarios. It's only when you have to crop in where more pixels are useful. For example, if you crop in from 16MP to 8MP, you increase your effective focal length by 1.41x (I think that's the math). If you crop down to 4MP, you've doubled your focal length. Now, 8MP is actually still fine for most use cases, though 4MP gets a bit tight for printing above 8x10, or large TV viewing. Going to a 20MP sensor only increases that 4MP to 5MP, and a 24MP sensor only increases it to 6MP for the same crop. You'd have to double the original resolution to 32MP to get a 2x crop of 8MP.
Now, most photographers will tell you that if you have to crop that much, your image is likely very off in the first place - and you'd need a very high resolution sensor to make up for that.
And this all leads up to my last point - sensor resolution only matters if you have lenses that can properly resolve the detail. For the same pixel density, a 16MP 4/3" sensor is equivalent to (roughly):
- 24MP APS-C sensor
- 64MP FF sensor
And what you're seeing on all formats is that as APS-C goes beyond 24MP and FF goes beyond 40MP, lenses and technique can't keep up - at a pixel level, you're not going to be as sharp as you'd expect. I see this with my m4/3 gear - my copy of the 35-100/2.8 is quite soft at 100mm/2.8, and while it's a little better at 100/4, it's still noticeably softer than at the wide end. That softness is magnified if I crop in, and going to a 20MP or 24MP sensor really wouldn't help things that much because sensor resolution isn't the limiting factor.
I'd much rather have a 16MP sensor with significantly better DR (pixel-level exposure would be cool) than a 32MP sensor with the same DR/noise characteristics that we have today. I'm usually comfortable with my framing decisions, but I'll always take more PP latitude.
Thanks aliasfox.
It's good to know that due to the pixel density that 16MP 4/3" sensor is approx equal to a 24MP APS-C sensor.
In your text you wrote "Now, 8MP is actually still fine for most use cases, though 4MP gets a bit tight for printing above 8x10, or large TV viewing".
Yet a 1080 x 1920 (2MP) video still looks good on a large 4K TV providing the Video Bitrate is not compressed too much.
PS: I don't know why they call it a 4k TV when the resolution is 3840 x 2160 = 8.2k
I have taking many photos of a subject at different zoom rates with my M43 camera so to reduce having to crop afterwards.
Brian
If you look at a 1080p video, it'll look incredibly sharp - I have no problem with 1080p blurays. If you look at a 1080p static image on a large TV, it will look slightly crunchy. Not bad by any means, but doesn't hold up well to detailed inspection on a 55" TV, for example.
A 4k TV is so called because its horizontal resolution is 3840 - nearly 4k pixels across (k in American means thousand, for million, use M). Theatrical 4k is 4160 IIRC, so slightly above 4k pixels across.