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11-18-2013, 06:16 AM   #31
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QuoteOriginally posted by Frater Quote
I also think it's exaggerated.

The K-5(ii) has a noise advantage over the K20D of ~1 EV, as per DXO labs. Assuming, that the K-3 and K-5 are in the same league (after netting off the resolution difference), then the K-3 will have an advantage ~ 1 EV as well. As soon as the K-3 will be DXOlab'ed, we will have the exact figures.

This assumes though, that we are talking about RAW, and that for High-ISO comparisons, the hidden (undesired) RAW denoising is switched off in both cameras (the K20D allows that in the unofficial debug mode), or has the same strength.
Part of my day job (at night I fight crime of course) is to test the equipment we manufacture and provide guaranteed specifications. So I'm quite used to the risks of not talking about the same exact quantities when discussing calculated specs. Or, as we say at work, "the devil's in the footnotes" meaning that the details of how the test was done, what it covers and deos not cover, is important.

I am saying that ISO 12800 is as usable as ISO 1600 in dark areas on the K20D. What I mean (I mentioned it above) is not that the noise per pixel is that much better. I am saying that the K-3 provides images at ISO 12800 that compare to those produced at ISO 1600 with the K20D.

The K-3 is 24 MP. It has a mode where you can operate it at 14 MP (that's what I do, most of the time, by the way). Now, look at images shot side by side with the K20D and the K-3 at 14 MP both and you might see what I mean. Or better, as I said, print images. You will see what I refer to.

DXO tests give you a number, which is useful, but is far from telling the whole story. It's just one test.

In any case, I know what I was comfortable doing with my K20D and what I am comfortable doing now with my K-3. YMMV.

QuoteOriginally posted by Frater Quote
Btw, does anyone know about another camera from another manufacturer out there, which has the same (Sony?) sensor as the K-3? Then we could lookup up the facts&figures even today (provided that the other cam would be DXO tested already)
Nikon D7100 by all accounts.

11-18-2013, 07:11 AM   #32
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QuoteQuote:
Nikon D7100 by all accounts.
The Nikon uses a similar sensor, arguably designed by Sony, but produced under licence from Toshiba!
11-18-2013, 08:27 AM   #33
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QuoteOriginally posted by bdery Quote
I am saying that ISO 12800 is as usable as ISO 1600 in dark areas on the K20D. What I mean (I mentioned it above) is not that the noise per pixel is that much better. I am saying that the K-3 provides images at ISO 12800 that compare to those produced at ISO 1600 with the K20D.
I have both cameras here. Let me know exactly how you would demonstrate this, and I'll do the test.
11-18-2013, 11:01 AM   #34
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QuoteOriginally posted by audiobomber Quote
I have both cameras here. Let me know exactly how you would demonstrate this, and I'll do the test.
The simplest (but least accurate) would be to compare both at 14 MP. The best (but difficult to do on the web) would be to print 12x8 or larger and compare.

11-18-2013, 12:22 PM   #35
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QuoteOriginally posted by bdery Quote
The simplest (but least accurate) would be to compare both at 14 MP. The best (but difficult to do on the web) would be to print 12x8 or larger and compare.
I firmly believe what you do to one, you should do to the other. My method would be to photograph a scene and cut out the same portion from each photo. This is equivalent to printing or viewing at the same resolution. NR set to OFF.

I've been meaning to do some test shots. I'll post my results some time this week. I predict I'll see what DXOMark results predict; one stop difference in SNR (K20D @ ISO 1600 = K-3 @ ISO 3200).
11-18-2013, 02:28 PM   #36
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QuoteOriginally posted by audiobomber Quote
I firmly believe what you do to one, you should do to the other. My method would be to photograph a scene and cut out the same portion from each photo. This is equivalent to printing or viewing at the same resolution. NR set to OFF.
I'm not sure I understand exactly what you mean, but if you plan on comparing noise on a per-pixel basis, then yes you will likely observe what DXO reports. But it will have no relation to the actual use of these cameras.

See it this way (I will exaggerate the numbers to illustrate) : if you look at a K20D image on your monitor and each pixel (which may or may not be noisy) occupies 2x2 pixels on the screen, and then compare with the same image shot with the K-3 and this time each image pixel occupies 1 pixel on your screen, the perceived noise performances will be vastly different. However, if you zoom in on the images so as to see individual pixels, then the noise performances will appear similar.

Said differently : the per pixel noise performance can be similar, but the global image will look better if there is more resolution, all things being equal.

On a side note : when using a camera, noise suppression is an integral part of the system, so I do not agree that it should be disabled. The point of my original comment was not to measure precisely which camera produces the most chroma or luminance noise per pixel. It was to say that the K-3 that I received in the mail, with its combination of sensor AND processing, is several stops better than my former K20D. It lets me take pictures that were not possible before, and that is why I upgraded.

That is all I have to say on the subject.
11-18-2013, 02:55 PM   #37
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QuoteOriginally posted by Frater Quote
The Kit has one disadvantage, after some years it seems to develop slight fogging, even if treated properly, i.e. some bright stuff (not organic or dark, i.e. not fungus) is finding its way onto at least one surface. My kit is 5 years old (the non-WR version II).
Is this separation of the laminated aspheric element?
11-18-2013, 07:24 PM   #38
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QuoteOriginally posted by lytrytyr Quote
Is this separation of the laminated aspheric element?

I wish I would know that! Did you hear about this happening or this being the reason?

Would be bad news, because this voids any hope that a simple lens element cleaning can fix this.

I didn't dare disassembling the kit yet, because its fogging is very slight (at this point of time at least), and I find this lens very useful for what it is, i.e. a reliable buddy e.g. for light-weight travel, pretty never getting ghosting bubbles due to only 11 elements, and around its sweet spot (around the 24mm mark) it performs almost like a limited prime lens.

And if you do e.g. 'auto contrast' in Photoshop, there's no difference to tell from shots with other clear lenses anyway.

Please have a look yourself with three photos:

1) we are looking from the back into the lens, where the damage appears deliberately exaggerated as much as possible, with the help of direct sunlight and a black shade, and the contrast is pushed up further in post-processing. You see it's not fungus, but an even spread of crystaline looking defects, which are probably (semi) transparent (not just white opaque stuff). Which may support your theory well.

2) an example shot with this lens at 40mm

3) the same shot with my DA 40mm Limited. Its sky is brighter and its tree is darker. But only slightly so.

For now the kit can get away with its fogging issue, and all I hope it doesn't get worse...

Attached Images
     

Last edited by Frater; 11-18-2013 at 07:41 PM.
11-18-2013, 08:30 PM   #39
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QuoteOriginally posted by Frater Quote
its fogging is very slight (at this point of time at least), and I find this lens very useful for what it is,

For now the kit can get away with its fogging issue, and all I hope it doesn't get worse...
Yes, it's probably sensible to keep using the lens,
until it no longer delivers the quality you need.

Those kit lenses are usually cheaper to replace than repair.
I got one when I bought a K-x camera four years ago.
The kit with lens was cheaper than the body alone!

By the way, it looks like you have some dirt on your sensor,
e.g., there's a smudge to the left of the main tree,
above where it intersects with the other tree in the background.
11-21-2013, 11:11 AM   #40
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QuoteOriginally posted by bdery Quote
Allright, I have been using the K-3 for a few days, having received it last Friday. I can comment on the changes between the K-3 and K20D to some extend.

First, the camera is fantastic. I'm sorry for all of you hesitating and wondering if you should upgrade. The truth is that it is an impressive upgrade from the K20D.

First, ergonomics. There are significant differences, enough that I sometimes have to look at the buttons placement. That's not to say it's bad, but there ARE differences. For instance, AF mode is now a combination of buttons instead of a rotating switch. Instead of pressing the FN button to access flash mode, drive mode, etc, you now toggle between those items and AF point selection. But most of the time, manipulating the camera comes naturally, I'm not lost like when I pick up a Nikon for instance.

I love that there is a dedicated button for ISO. I actually like the way the AF selection works. I love the live view button and the movie/stills switch. I think that the metering/erase button is too near the viewfinder but that's about it for grievances. I'll mention that I have not found a way to light up the top LCD except by configuring the Fx button to do so (it's OK, I would not have used any other of the proposed options).

Speaking of the top LCD, there is now a truckload of information dislayed on it. Info on both cards, ISO and rmaining shots, metering, exposure, drive mode, and much more. I like that I can display the inclination and still have the compensation scale by pressing the EV compensation button.

Pressing such a button once keeps the option active until another action is performed, which is very nice.

The body is smaller but has the same weigth. The grip is different, but excellent, well shaped, comfortable. It feels as natural as the K20D's, which says something.

The screen is just amazing. Large, bright, high-res.

Let's move to actual shooting...

The shutter is so silent it's hardly believable, coming from the K20D. I was not sure it had taken a picture the first time. It's soft and smooth. And fast. It's not something often measured in reviews is the time it takes to take the picture when you press the shutter. THAT is really, really fast. I thought there was no delay before, but it's shorter now.

Burst mode is absurdly fast. that's it.

AF is wonderful. It IS faster. With all my lenses. It's also much more flexible with the new AF points. I currently use the AF auto 9 points, and it's nice. I can move it around as if it was a single spot. Love it. I used to operate with the SEL mode, moing my point around. This is similar but with some added flexibility. I have not yet tested the AF in really low light but it hasn't left me wanting in any situation so far.

Metering is better, very much so. Even in multi-zone, on strongly backlit scenes, it performed well. I'm not yet really familiar with the new way to change metering but I'll manage. That's one thing I prefered on the K20D, the switch was really nice and intuitive.

SR is good, as I'd expect. Hard to evaluate if it's better, it's clearly not worse. It also activates much faster, there was some delay before it was active with the K20D, hardly delay now.

ISO... that's the main reason why I upgraded. I'll just say this : ISO 12800 on the K-3 is about comparable to ISO 1000 on the K20D. I'll use it if I must, but I set auto ISO (which I rarely use) to operate between 200 and 6400. I also found something amazing. There is a "program line" for ISO, prioritizing low ISO, speed or something in between (I use speed).

Let's talk about the viewfinder. It's visibly larger, bright, but the K20D was not lacking in this. There is a lot more info displayed. I really like that the camera shows if I'm set to move the AF points or not. For the rest, almost everything you'd want to see is there.

Operation speed : it's so fast! Instant replay is instantaneous, navigating menues is quick, scanning photos in playback is extremely fast, it's just smoother.

Menues. They are very logical coming from the K20D. I went through them all once, setting things as I went, and I'm already comfortable with most options and settings. Some new things will require experimenting but for the most part I knew what I wanted and where to set it. Kudos.

Now there is one thing I can't get my head around yet. By default the back LCD is always on except when you half-press the shutter. Now I don't like that. You can turn it off easily. But on the K20D when you pressed the Info button once you got the exposure data. That's what I'd like. On the K-3 if the screen is off and you press Info, you get the screen where you can move the cursor around and change all sorts of settings, like HDR, noise reduction, etc. It's a powerful and useful screen but not usually the one I want to see.

That was pretty long-winded, but I hope it's helpful. I loved the K20D and the K-3 is a worthy upgrade. I really, really enjoy using it.
This K20d review is spot on with my experiences with one small addition. I have been slightly slowed down by the new position of the green button. Obviously this is just something to get used to, but worth noting.
11-21-2013, 11:45 AM   #41
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QuoteOriginally posted by audiobomber Quote
I've been meaning to do some test shots. I'll post my results some time this week. I predict I'll see what DXOMark results predict; one stop difference in SNR (K20D @ ISO 1600 = K-3 @ ISO 3200).
I find that hard to believe.
I took my Panny GX1 on vacation last month because I didn't think I'd be able to get a K-3 in time and it has ISO1600 comparable to the K20D's ISO800 and it's a m4/3 sensor. From what I've seen of samples posted, the K20D's ISO800 is more like the K-3's ISO6400 in dim light (we're not talking about using it for more shutter speed in bright sunlight in which case your comparison might be true)...
Sensors today are far better than the K20D's in low light...I'd expect the OM-D EM1 to be within a stop or maybe 1.5 of the K-3's performance in low light...
11-21-2013, 01:37 PM   #42
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QuoteOriginally posted by kenyee Quote
I find that hard to believe.
I took my Panny GX1 on vacation last month because I didn't think I'd be able to get a K-3 in time and it has ISO1600 comparable to the K20D's ISO800 and it's a m4/3 sensor. From what I've seen of samples posted, the K20D's ISO800 is more like the K-3's ISO6400 in dim light (we're not talking about using it for more shutter speed in bright sunlight in which case your comparison might be true)...
Sensors today are far better than the K20D's in low light...I'd expect the OM-D EM1 to be within a stop or maybe 1.5 of the K-3's performance in low light...
No, you need to check DXOMark for real world SNR measurements.
OM-D E-M1 = ISO 757
Pentax K20D = ISO 639
GX-1 = 703
There's only a fraction of a stop difference. Check the SNR graph, The K20D and GX-1 lines are on top of one another is not even 1/3 stop better. If that's not what you're seeing, you aren't viewing the same noise reduction, or the ISO values are manipulated. Olympus is famous for this. DXO levels the playing field. Intensity of light does not affect the signal to noise reading for a given ISO setting.

The Nikon D5300 SNR score is ISO 1338, about one stop better, which is where the K-3 will score.

Compare cameras side by side - DxOMark
11-21-2013, 02:49 PM   #43
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QuoteOriginally posted by audiobomber Quote
No, you need to check DXOMark for real world SNR measurements.
OM-D E-M1 = ISO 757
Pentax K20D = ISO 639
GX-1 = 703
There's only a fraction of a stop difference. Check the SNR graph, The K20D and GX-1 lines are on top of one another is not even 1/3 stop better. If that's not what you're seeing, you aren't viewing the same noise reduction,
I'm basing it on what the images look like to my eyes...I hated shooting the K20D in low light at anything above ISO800, but I'm ok w/ the GX1's images up to ISO1600.
Interesting that DXO says they're pretty much the same...
11-21-2013, 04:49 PM   #44
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QuoteOriginally posted by kenyee Quote
I'm basing it on what the images look like to my eyes...I hated shooting the K20D in low light at anything above ISO800, but I'm ok w/ the GX1's images up to ISO1600.
Interesting that DXO says they're pretty much the same...
Click on MEASUREMENTS in the link I posted above, then click on the ISO SENSITIVITY tab. Put your cursor over the Panasonic graph at the ISO 1600 point. It says MANUFACTURER ISO 1600, MEASURED ISO 957. Different noise reduction treatments in the camera or software can have an equally significant effect on the perception of noise.
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