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12-14-2011, 12:29 PM   #31
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QuoteOriginally posted by Edgar_in_Indy Quote
I could see other scenarios where cropping could be useful. For example, you may take a nice photograph of a building, and from the same photo you might be able to crop a separate image of a detail on the building. Or if you're shooting sports or a stage performance, but your lens isn't as long as you would like, cropping can simulate a longer lens. But the amount you will be able to "zoom" will be limited by the resolution of your original image.

And I don't care how good of a photographer you are, you will sometimes get some soft shots. This can be caused by missing focus, or by your subject moving out of focus or being slightly blurred by movement. This happens a lot with kids since they sometimes have trouble holding still. With a very high resolution photo, some of these shots can still be saved.

All of the above reasons are why I'm annoyed when people moan about the "megapixel" wars. There seems to be a knee jerk reaction among some people to "just say no" to more megapixels, without fully considering the advantages of increased resolution.
I'm afraid you are somewhat overestimating what more pixels can do for you. You can only crop until something limits your resolution. That can be sensor resolution, but all of the reasons in the second quoted paragraph are something else. (And in the first paragraph you are also assuming a lens that is good enough, which isn't always the case.)

I, personally, rarely get everything good enough that the 16MP of my K5 are the limiting factor of image resolution. For this reason I, again personally, don't see any need to have more resolution, but I do see a downside. (Same electronics will make the camera seem slower, the same computer will take longer to do things. And since I want RAW I can't just lower the resolution.)

12-14-2011, 06:56 PM   #32
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QuoteOriginally posted by drougge Quote
I'm afraid you are somewhat overestimating what more pixels can do for you. You can only crop until something limits your resolution. That can be sensor resolution, but all of the reasons in the second quoted paragraph are something else.
I'm not suggesting adding empty megapixels. That should go without saying. If all I want is a larger image file, I can just resize it in Photoshop. And I don't want needlessly large and cumbersome files any more than the next guy. So all of the scenarios I mentioned earlier in favor of a higher-megapixel Pentax DSLR only make sense if there is an increase in actual resolution.

I owned a Canon t2i (18mp) before buying the K-x, and I had a chance to do direct comparisons. The 18mp sensor was not just hype, it did actually provide more resolution than the K-x, even with the kit lens. I've also looked at numerous sample pictures from other high-megapixel DSLRs, and the increases in resolution are real.

QuoteOriginally posted by drougge Quote
I, personally, rarely get everything good enough that the 16MP of my K5 are the limiting factor of image resolution.
But as I already mentioned, I shoot a lot in the studio at base ISO and I use sharp lenses, so in my case the resolution is limited by the 12mp sensor. Here's an image I shot a couple days ago in my studio. If you click on the picture to view the full size image, you'll be able to see that there's not much resolution being left on the table due to problems with the lens, focus, lighting, etc.

12-14-2011, 09:35 PM   #33
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QuoteOriginally posted by Edgar_in_Indy Quote
I'm not suggesting adding empty megapixels. That should go without saying. If all I want is a larger image file, I can just resize it in Photoshop. And I don't want needlessly large and cumbersome files any more than the next guy. So all of the scenarios I mentioned earlier in favor of a higher-megapixel Pentax DSLR only make sense if there is an increase in actual resolution.

I owned a Canon t2i (18mp) before buying the K-x, and I had a chance to do direct comparisons. The 18mp sensor was not just hype, it did actually provide more resolution than the K-x, even with the kit lens. I've also looked at numerous sample pictures from other high-megapixel DSLRs, and the increases in resolution are real.
Of course more resolution is real under good conditions, such as you may well have in a studio. But blur caused by missed focus or subject motion gain nothing from more pixels. You will end up with the same final resolution when resizing the files until they appear sharp. (And you did argue that both these scenarios would benefit from more pixels.)

My other point was that people who don't shoot as you do may well get only a downside from pixels you would benefit from. Or in other words, not everyone who doesn't want more pixels is "wrong".
12-15-2011, 12:30 AM   #34
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There is also the issue of whether all those megapixels actually turn into higher resolution.

Once again, turning to the photoreview.com.au resolution charts (just for consistency), it doesn't look like the 18MP of the Canon 60D delivers a whole lot more resolution than the 12MP K-x:



AA filters, lenses, in-camera data processing etc seem to play as much a part as the megapickles in delivering usable resolution.

12-15-2011, 07:15 AM   #35
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QuoteOriginally posted by rawr Quote
There is also the issue of whether all those megapixels actually turn into higher resolution.

Once again, turning to the photoreview.com.au resolution charts (just for consistency), it doesn't look like the 18MP of the Canon 60D delivers a whole lot more resolution than the 12MP K-x:
It's certainly true that not all megapixels are created equal, as is evidenced by all the point & shoot cameras with ridiculous 12 and 16mp sensors, but I haven't found this to be as true in DSLRs. As I mentioned above, I owned the 18mp Canon t2i and the 12mp K-x at the same time and was able to do direct comparisons.

To further illustrate my point, I took a crop from four different DSLRs from the Imaging Resource test scene, all shot at the camera's base ISO. Pay particular attention to the words "Pure Brewed", and how the white spaces between the horizontal black lines are rendered. Also look at the seal, and the tiny text above and below it, and how it becomes much more legible as the megapixels increase. From what I can see, the resolution differences between these cameras are real and significant.




Last edited by Edgar_in_Indy; 12-15-2011 at 11:44 AM.
12-17-2011, 12:15 PM   #36
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IQ of HighISO and even Mp are dependent on actual usage and end results needed.

A photo may well be noisy when viewed 100% - but when downsized to a viewable image on the web
(mostly 800x600 or sometimes 1024x768 pixels max) a lot of noise is "mitigated" -
or at least start becoming acceptable -
as for a typical web sized image of 400x300 - even a ISO12800 probably is acceptable
(this is due to the auto-correlation/self-cancelling random nature of noise).

Therefore an argument might be taken that the more megapixels the better - since one can then downsize a lot more with a lot more noise self-cancelling.

This may seem true to a certain extent - if everything else was equal - but as most people here know this just isn't case - the more pixels squeezed onto the same sized sensor chip - the smaller those pixel sites are - therefore less area to capture light - hence noisier.

A 24Mp sensor on the Sony NEX-7 (or A77 or A65) is astonishing for what it achieves - the signal to noise ratio is unheard of for anything in a consumer sensor at such tight densities.

BUT look at it another way if the same equal technology were applied to a 12Mp chip the signal to noise ratio would be a lot better than the K-x or K-r - possibly rivaling the current 12Mp FF dSLRs.

I understand the advantages of more Mp - 24Mp is desirable for some applications - but 12Mp is no slouch and probably more than adequate for most people.

At one time the criteria for IQ was a 10x8 print - in fact it is still so for the publishing industry.

Most publishers would ask for a 300dpi image (without any qualifications -
which is basically totally meaningless without any other dimensions) -
for the common submission this probably would have been more likely a 6"x4" print -
and at 300dpi this is a mere 1800x1200 pixels - about a 2Mp image.......

For pro quality this ought to be a 10x8 print submission -
@ 300dpi = 3000x2400 pixels about a 6Mp
hence the rush to digital by pros when the 6Mp dSLRs first arrived.

This would be good enough for a glossy magazine cover.

So in the humble K-x we have 12Mp =
2-page center spread
(in any well known magazine - Play?)

There also has been a long standing contention that says if one can print for the largest handheld print that can pass very close scrutiny - eg: nose to paper - then any larger print at correspondingly larger viewing distance will be fine.

The normal "correct" viewing distance is supposed to be equal to the diagonal of the print - and the closest optimal distance for the human eye is supposed to be about 25cm or 10 inches. That's why the long standing critical print size has been 10x8 (diagonal = 12.8")....
(actually strictly speaking a 10" diagonal print is 8x6 )

So the theory is that if one can print to 10x8 at critical "quality" - then anything larger will be OK (again caveat at normal viewing distances).

Of course again this breaks down if one goes very close to the print - (changes the viewing distance) - and for camera nuts - this may not be adequate...... but for most people this is OK.

200ppi had been held as a mark of quality for digital prints - so a 10x8 is a mere 2000x1600 pixels = 3Mp - that maybe why Canon produced their first dSLR at 3Mp level the Canon EOS D30 (not to be confused with the 30D).....

However these days with more Mp this printing density has raised to 300ppi - which is close to the critical 6lp/mm print resolution (= 305 ppi) especially for smaller prints like 6x4 or 7x5 -
if one extends this 300ppi to 10x8 - then that's 3000 x 2400 ....about 6Mp
That is why the rush of dSLRs was when it reached 6Mp
(actually strictly speaking since a 10" diagonal print is 8x6 that pixel count at 300ppi is only 4.32Mp!!!)

So "in theory" anything 6Mp and above should be able to handle almost "any amount" of enlargement for the corresponding correct viewing distance.

So perhaps a 12Mp using the same equal technology as the 24Mp in the Sony NEX-7 would yield a sensor that would show noticeable and worthwhile improvement in noise performance over the K-x/K-r?

UK TV the Gadget show had a video showing 12mp Nikon D700 enlargement to 17 x10 metres! using ISO400....
The video has not been available for quite a while now from the USA
(and has been reported not viewable from the UK either)

I uploaded the .flv video for anyone who wants to view it -

Link

Last edited by UnknownVT; 06-11-2012 at 12:24 AM.
06-10-2012, 10:24 PM   #37
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QuoteOriginally posted by olivemike Quote
If you go to the end of the K5 or Kx review at dpreview.com, you'll find an interactive comparison chart to compare almost all active and some inactive cameras. Interestingly enough, the Kx is shown to outperform the K5 from a Low Light, High ISO standpoint. Does anyone believe this to be true?
My answer to this question is a Resounding TRUE!!!

Basing from my experience from both bodies (K-X upgraded to K5), K-X at high ISO will definitely run-over the K5 anytime...
I am comfortable using my K-X @ 1600 EVERYTIME I'm i a low light location but for K5? 1000 at best without being bothered by the noise...

If you're planning to get the K5 because of better ISO? DON'T!!! you'll be disappointed and that's an understatement...

Am just waiting for K30 reviews/opinions/test/etc... planning to downgrade to K30 (if ISO/AF/etc results are good) or going back to my tested K-X body...

Note: I don't mean that K5 is not good, it is an all-around performer but i need my low-light capabilities more than any other things...

Peace...& GOD Bless
06-14-2012, 08:48 AM   #38
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Don't know about that large but I have printed 30x20 inches with the K-x in B&W and it looks fantastic. The K-x is known to have a weak AA filter and I have found in comparison with my K-5 that the K-x provides virtually the same level of detail as the K-5! I was hoping for a big jump in detail with the K-5 and was a little disappointed but that's only because my K-x was always pumping out detail well in excess of most 12MP cams.


QuoteOriginally posted by UnknownVT Quote
Do people remember that video linked in the thread -

How can they print that big with only 12mp?

From the UK TV The Gadget Show -
where they blew up a shot from a 12Mp Nikon D700.
(I can't now view the video from the USA....
- but I had saved a copy back when the thread was current
Hopefully people in the UK may still be able to see it?)
but the gist is they printed to 17x10 metres(!)
and on the video the print looked not just "acceptable",
but great even on close ups, easily beating out the ISO400 35mm film shot......

The K-x is only 12Mp

I uploaded the .flv video for anyone who wants to view it -
it was very enlightening -

Link


06-16-2012, 01:02 AM   #39
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QuoteOriginally posted by HoBykoYan Quote
My answer to this question is a Resounding TRUE!!!

Basing from my experience from both bodies (K-X upgraded to K5), K-X at high ISO will definitely run-over the K5 anytime...
I am comfortable using my K-X @ 1600 EVERYTIME I'm i a low light location but for K5? 1000 at best without being bothered by the noise...

If you're planning to get the K5 because of better ISO? DON'T!!! you'll be disappointed and that's an understatement...

Am just waiting for K30 reviews/opinions/test/etc... planning to downgrade to K30 (if ISO/AF/etc results are good) or going back to my tested K-X body...

Note: I don't mean that K5 is not good, it is an all-around performer but i need my low-light capabilities more than any other things...

Peace...& GOD Bless
I have no hesitation using my K-5 at ISO3200 and ISO6400. Of course it doesn't prove anything, though I believe other K-5 users have pointed to ISO6400 too. Is it possible you were using high sharpening and/or contrast when shooting K-5 which produced some artifacts that you thought was noise? Just a wild guess. How long have you played with the K-5?
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