What is the minimum usable megapixel count ?

What, in your opinion, is the minimum MP count that still makes a camera useful for most purposes ? I ask because the megapixel wars of the last few years seem pretty pointless and I believe camera makers should instead concentrate on improving sensor performance. (Yes I understand that MP count is easily marketable).

I would say 5-6 MP is probably the lowest limit for me, where photos are still large enough for prints or large screens. At 10-12 MP, you have room for reasonable cropping. Anything above 16MP is a luxury, and perhaps an unnecessary excess - if it comes at a price of reduced sensor performance.

I'd say that the camera makers are doing a "juggling act", coming out with more megapixels, but then also working on IQ. We do benefit, though, when high-res bodies come out with good IQ!

The one thing to be said about "more megapixels" is that if the IQ is good, they allow for larger prints, and that's a good thing for folks who want to print large!

As to the "minimum", well, I'd say "it depends". For large prints, sure, it's a consideration. I shot with several P&S and compact cameras before "upgrading" to DSLRs. The resolutions of the smaller cameras varied: 4MP, 5MP and 6MP. I have prints I made and framed from those cameras, 12x16 prints. Because the pics are "visually appealing" they look nice adorning the walls, but get up close and sure, not good on the fine details! But prints I've made from my trusty ol' 8MP 30D stand up very well to close scrutiny at that print size (or 12x18)!

Amamba wrote in post #16239856
What, in your opinion, is the minimum MP count that still makes a camera useful for most purposes ? I ask because the megapixel wars of the last few years seem pretty pointless and I believe camera makers should instead concentrate on improving sensor performance. (Yes I understand that MP count is easily marketable).

I would say 5-6 MP is probably the lowest limit for me, where photos are still large enough for prints or large screens. At 10-12 MP, you have room for reasonable cropping. Anything above 16MP is a luxury, and perhaps an unnecessary excess - if it comes at a price of reduced sensor performance.

Depends what you shoot, and if you're focal-length starved (i just can't afford a 500mm or larger lens).. like most of us are. I can crop a bird shot, much more with my 18MP, and 20+ would be a bonus. Of course, i don't want it, at the cost of IQ, or worse high-ISO ability, as you've stated.

I never converted from film to dSLR until 8Mpixel bodies were affordable...that is my lower limit.

Wilt wrote in post #16240094
I never converted from film to dSLR until 8Mpixel bodies were affordable...that is my lower limit.

It's true that the Canon 8MP 10D started a "bit of a revolution" amongst film shooters, it was fun to watch!

tonylong wrote in post #16240133
It's true that the Canon 8MP 10D started a "bit of a revolution" amongst film shooters, it was fun to watch!

The Canon 10D was only 6.3Mpixel; I did not buy a dSLR until the 8Mpixel 20D was launched.

Wilt wrote in post #16240149
The Canon 10D was only 6.3Mpixel; I did not buy a dSLR until the 8Mpixel 20D was launched.

Ah, OK, but I'm not kidding that the 10D really did cause some "commotion", people that were died-in-the-wool film shooters turning over to the 10D!

My first DSLR was 5Mpix. I don't use it anymore, but I have the pictures in my archive. And even this year, I had pictures from this camera in both a book and a magazine. So it is enough for profesional works.

It depends what you mean by that ambiguous phrase "most purposes". Many people never make a print bigger than 4x6 for which 1200x1800 pixels (2.16 Mp)is enough. Personally, I need high quality 20x30 prints, for which 54 Mp would be optimum, but I'm forced to acept the "close enough" of 21 Mp.

Not for me they aren't. If I wasn't heavily (for me) invested in Canon lenses I would have jumped to the D800 (36 Mp). Pixel count needs to be understood in the context of sensor size - the 21 Mp 5D2 and the 22 Mp 5D3 have the same same size and density of pixels as the 8 Mp croppers (20D/30D) but because of the larger sensor they have 2.56 as many pixels. The D800 has the same pixel density as would have a 14 Mp 1.6 cropper. Neither of these pixel sizes have sacrificed much "sensor performance". In fact the 6.4 micron pixel of the 5D2/20D/30D is considered by many to be the optimum size.

Depends on the purpose though. I've made "new shots" out of originals by cropping from horizontal to vertical - and printing those is pretty knuckle whitening. Especially when a client paid a premium for it. For 90% of what I shoot I could get away with 3 or 4MP (keep in mind that 1080p TVs are only 2MP) but then there's that 10% and it's not worth having a separate camera for those.

Having said that, I always shoot at the highest resolution on my cameras.

Many publishers prefer that submitted images have enough pixels to allow them to print at 300 or 330 dpi without having to interpolate (upsize). For a double-page spread of 10 inches by 17 inches, at 300 dpi, this would mean an image 5100 pixels on the long side - which, for a 3:2 aspect ratio sensor, means 3400 pixels on the short side . . . a total of 17.34 megapixels.

Of course, 10 inches by 17 inches isn't really that large. I would think that if most people wanted to print something to hang on their wall, they would want it to be at least 16" by 24" (preserving the native aspect ratio). This would mean that even a 21 megapixel camera would require a great degree of upsizing in order to print at 300 dpi. in fact, the only digital SLR that I know of that would allow one to print at such a size & resolution (without upsizing) is the Nikon D800. And this is just for a rather small 16 by 24 inch print. Think of what a 30 by 40 inch print would require!

Lots & lots of megapixels aren't a bad thing, if one wants to print images at a reasonable size and resolution without interpolation. Large prints often are viewed at very close range, so being able to print at maximum resolution really is important for many situations.

Tom Reichner wrote in post #16240313
Large prints sometimes are scrutinized at very close range

Fixed that for you. Most normal people stand back far enough to see the image for what it is.

cdifoto wrote in post #16240322
Fixed that for you. Most normal people stand back far enough to see the image for what it is.

Normal? Who's normal?

tzalman wrote in post #16240341
Normal? Who's normal?

Nobody here, of course!

1st digital I bought was a D60, and I still thoroughly enjoy looking at images produced by it. (6.3Mp)