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11-03-2010, 05:04 PM   #46
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QuoteOriginally posted by Class A Quote
Hi and welcome to the forum. It is great to see that you are enjoying the K-5 and Pentax lenses and that there are users out there that prefer the K-5 over the Canon 7D. Good news for Pentax.


That's fine but on the other hand then you cannot really comment on the low light abilities of the cameras. The fact that the 5D is an FF camera doesn't make it better suited for low light. It gives it a headstart regarding dynamic range and you'll have faster (after crop factor conversion of the f-stops) lenses available for it, but FF sensors do not intrinsically have a lower noise floor. I'd be surprised to see a significant difference between the 5D and the K-5. We'll know for sure when DxO has measured the K-5.

BTW, regarding the comparison of shots between cameras at various ISO levels not that manufacturers lie in various degrees regarding true ISO values. For instance, ISO 6400 for a Canon 5D Mk II really means ISO 3390 and ISO 6400 for a Pentax K-7 really means ISO 5797. That's over 2/3 of a stop difference of noise advantage the Canon obtains by cheating on the ISO value. One should bear this in mind when comparing shots.
I understand what you're saying, and it makes sense. I'll let others who are more into the pixel-peeping and better at the numbers make their case about the low-light performance of one camera over another. For me, it's about the image, and having a camera that doesn't limit my ability to capture a moment in time. So, as long as the camera is capable of allowing me to capture an image as I imagine it, I'm happy. The bottom line is that the K-5, K-7 and 5D Mark II are all excellent cameras, especially when compared to what we had at our disposal five years ago. The fact that we can shoot in near darkness, and still capture an image is amazing to me!

The other thing I want to point out: Outside of photographers who make a living shooting concerts or other low-light events like weddings, where the use of flash isn't an option, most of what we shoot is at ISO 1600 or less. Don't get me wrong - being able to ratchet up the ISO sensitivity to 6400 is fantastic, and I wouldn't want to be without it. However, qualities like dynamic range, color rendition, and sharpness are at least as important as ISO sensitivity. And it's in these areas, especially color, where I think the K-5 really excels. The fact that it also performs well at ISO 6400 is icing on the cake.

I'm really hoping I can get out to the night club where our friend's band is playing this weekend, to see what the K-5 can do in those conditions. Assuming the club has a great lighting setup, it should be a lot of fun to shoot.

11-03-2010, 06:17 PM   #47
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QuoteOriginally posted by falconeye Quote
1. Imaging Resource applies ACR with default settings which applies demosaicing, tone mapping and some NR. Not having an own raw converter, it's the best you can do.
I'm not sure I'm agreeing with this. ACR is known to apply specific treatment depending on the camera model. Therefore, for comparison purposes, it would make sense to use a neutral converter such as dcraw or RAWTherapee.
11-03-2010, 06:22 PM   #48
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QuoteOriginally posted by Feudal1 Quote
For me, it's about the image, and having a camera that doesn't limit my ability to capture a moment in time.
Absolutely. That's why handling is also an important component in evaluating a camera.

QuoteOriginally posted by Feudal1 Quote
So, as long as the camera is capable of allowing me to capture an image as I imagine it, I'm happy.
I agree and I also agree that while there is always room for better and more, the quality provided by the K-5 is nothing short of astonishing and we can consider ourselves lucky to have such technology at our disposal.

QuoteOriginally posted by Feudal1 Quote
However, qualities like dynamic range, color rendition, and sharpness are at least as important as ISO sensitivity.
Again, I fully agree. For my personally, colour sensitivity is very important and I'd rather have a camera that does well in this area than one that excels in high ISO.

Good luck and lots of fun with your club shoot.
11-04-2010, 02:14 AM   #49
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QuoteOriginally posted by Feudal1 Quote
No worries Raz.

I think the K-5 is extremely impressive for an APS format camera. I shot a Canon 7D for a weekend shortly after it came out, and was pretty disappointed with the camera in general. The K-5 is a real nice surprise.
Congrats on your K-5 looks like a great camera and I am thinking of buying it as well, but what were you disappointed with the 7D? I think it is a fantastic camera and don't know if the K-5 will beat it.

11-04-2010, 02:21 AM   #50
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QuoteOriginally posted by Class A Quote

That's fine but on the other hand then you cannot really comment on the low light abilities of the cameras. The fact that the 5D is an FF camera doesn't make it better suited for low light. It gives it a headstart regarding dynamic range and you'll have faster (after crop factor conversion of the f-stops) lenses available for it, but FF sensors do not intrinsically have a lower noise floor. I'd be surprised to see a significant difference between the 5D and the K-5. We'll know for sure when DxO has measured the K-5.

BTW, regarding the comparison of shots between cameras at various ISO levels not that manufacturers lie in various degrees regarding true ISO values. For instance, ISO 6400 for a Canon 5D Mk II really means ISO 3390 and ISO 6400 for a Pentax K-7 really means ISO 5797. That's over 2/3 of a stop difference of noise advantage the Canon obtains by cheating on the ISO value. One should bear this in mind when comparing shots.
ISO 6400 means ISO 3390? you wish, where did you hear this from? it is wrong. See I also like Pentax as I do Canon but when the Kr came out it was a FF beater by all in Pentax forums and it only scored low light ISO 755, how much better can the K-5 be? maybe a little but it isn't going to get to the 5D II level of 1815 sorry.
11-04-2010, 03:21 AM   #51
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QuoteOriginally posted by SpartanWarrior Quote
ISO 6400 means ISO 3390? you wish, where did you hear this from? it is wrong. See I also like Pentax as I do Canon but when the Kr came out it was a FF beater by all in Pentax forums and it only scored low light ISO 755, how much better can the K-5 be? maybe a little but it isn't going to get to the 5D II level of 1815 sorry.
Dxo attempts to measure the actual iso of each camera versus stated iso. The graph for the 5D MkII is here: (DxOMark - Canon EOS 5D Mark II). As far as I can tell, all camera companies over state their iso to a certain extent, but some do it more than others.
11-04-2010, 03:25 AM   #52
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QuoteOriginally posted by Rondec Quote
Dxo attempts to measure the actual iso of each camera versus stated iso. The graph for the 5D MkII is here: (DxOMark - Canon EOS 5D Mark II). As far as I can tell, all camera companies over state their iso to a certain extent, but some do it more than others.
Ya I know that but not in half, I am so sure ISO 6400 in the 5D II is actually half of that, which is the most stupidest thing I have ever heard.
11-04-2010, 04:10 AM   #53
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QuoteOriginally posted by SpartanWarrior Quote
Ya I know that but not in half, I am so sure ISO 6400 in the 5D II is actually half of that, which is the most stupidest thing I have ever heard.
MMmm yeah, better keep our convictions rather than think, good idea.

11-04-2010, 04:13 AM   #54
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QuoteOriginally posted by SpartanWarrior Quote
when the Kr came out it was a FF beater by all in Pentax forums and it only scored low light ISO 755, how much better can the K-5 be? maybe a little but it isn't going to get to the 5D II level of 1815 sorry.
Not all, not me. I always pointed out that low light performance of FF is out of reach. After all, it's because at the same f-stop and same FoV, FF lenses have twice the surface. How should this change?

However, as far as DR is concerned, the gap may be closing though (until the next batch of FF sensors emerges).

QuoteOriginally posted by SpartanWarrior Quote
Ya I know that but not in half, I am so sure ISO 6400 in the 5D II is actually half of that, which is the most stupidest thing I have ever heard.
There is an ISO standard for ISO sensitivy (what a surprise ), it is ISO Standard 12232.

However -- and Kodak stated that quite clearly in some paper regarding their film speeds -- it is not mandatory when labelling a recording media's sensitivity. It's more a synchronization means between camera and exposure meter.

Kodak recommends a testing procedure which would give the professional media (film intended for professional or studio use or larger format) a higher iso label, for added headroom in the highlights.

Looking at the sensitivity curve for Canon's FF and APSC cameras, Canon seems to do the same. Just add extra headroom in the highlights for FF (shift iso) because there is extra headroom in the shadows too. The only thing they miss to do is revert the correction at higher iso (where the shadow headroom (footroom?) disappears). BTW, Canon duplicates their low iso sensitivity (73) as both ISO 100 and ISO 50

Last edited by falconeye; 11-04-2010 at 04:18 AM.
11-04-2010, 04:13 AM   #55
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I don't know about how Dxo measures these things, but I think they are honest. They certainly show the 5D to be a better low light camera than the Kx and D90 ("sports iso" of 1800 for 5D versus 800 for the other two). However you can't really pick and choose which Dxo numbers you believe and which ones you don't since their methodology remains the same for all of them.
11-04-2010, 04:49 AM   #56
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QuoteOriginally posted by falconeye Quote
Not all, not me. I always pointed out that low light performance of FF is out of reach. After all, it's because at the same f-stop and same FoV, FF lenses have twice the surface. How should this change?

However, as far as DR is concerned, the gap may be closing though (until the next batch of FF sensors emerges).


There is an ISO standard for ISO sensitivy (what a surprise ), it is ISO Standard 12232.

However -- and Kodak stated that quite clearly in some paper regarding their film speeds -- it is not mandatory when labelling a recording media's sensitivity. It's more a synchronization means between camera and exposure meter.

Kodak recommends a testing procedure which would give the professional media (film intended for professional or studio use or larger format) a higher iso label, for added headroom in the highlights.

Looking at the sensitivity curve for Canon's FF and APSC cameras, Canon seems to do the same. Just add extra headroom in the highlights for FF (shift iso) because there is extra headroom in the shadows too. The only thing they miss to do is revert the correction at higher iso (where the shadow headroom (footroom?) disappears). BTW, Canon duplicates their low iso sensitivity (73) as both ISO 100 and ISO 50
I will agree with you on Dynamic Range
ps I wasn't referring to you as I am more talking about dpreview forum, when you and GordonBGood write stuff I actually listen
11-04-2010, 08:06 AM   #57
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The implications of "overstated" ISO gain

QuoteOriginally posted by falconeye Quote
...

There is an ISO standard for ISO sensitivy (what a surprise ), it is ISO Standard 12232.

However -- and Kodak stated that quite clearly in some paper regarding their film speeds -- it is not mandatory when labelling a recording media's sensitivity. It's more a synchronization means between camera and exposure meter...
Which means that photos taken with the camera that applies less ISO gain will receive more exposure, if exposure is based on the meter. In comparisons for noise and detail at a given IO, that gives an advantage to the camera that applies less ISO gain.

It also means that for photos taken at the same ISO and exposure, the photo from the camera that applies less ISO gain will be darker. Some review sites compensate for this by increasing exposure on that camera, again giving it an unfair advantage.

A fair comparison requires the same ISO and exposure for both cameras, followed by a digital boost, on the computer, to the levels of the darker photo, so that it matches the levels of the other photo.

Manufacturers are not cheating when they "overstate" the ISO gain a camera applies compared to other cameras, but the results can be deceiving.

Last edited by Jeff Charles; 11-04-2010 at 08:15 AM. Reason: edited for more clarity (I hope)
11-04-2010, 04:51 PM   #58
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That's correct. Shifted ISO isn't necessarily in attempt to cheat but to preserve the precious highlights on sensors with a strong shadow performance. However, I would still prefer an optional "preserve highlight mode" like Pentax does.

Its true, it makes life more complicated for testing labs which, as you correctly observe, must normalize brightness prior to analysis (but only with lenses with a good transmission, read simple primes). DxO does so, DPReview doesn't. Another reason to prefer one result over the over ...
11-04-2010, 06:42 PM   #59
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Shifting conversation back to the K-5 for a moment...

I received the Metz 58 AF-1 flash today, along with the DA* 55mm f/1.4. Took some test shots with the K-5/flash combo, and noticed some inconsistency in exposure. Not a huge deal, but it definitely takes a little more work to get things looking right. I downloaded and applied the latest firmware for the flash, but that didn't really make a difference. The other thing that was a little troubling was the fact that the flash emits a bit of a burning/plastic-melting smell after a few shots. I'm used to the Canon and Nikon flashes, which are very well built and very consistent in how they handle exposure. So a little disappointing there.

On the other hand, the DA* 55mm f/1.4 lens is a real gem. The size, sharpness, bokeh, and general image quality are really nice. No doubt, it will make a good portrait lens.

I have attached a couple more shots. The one of my cat was taken with the 55mm, using bounced flash as the main light source. The other is one of a cherry tree in our yard that has lost most of its leaves, but not the berries. The K-5 handles the reds very well, and creates a realistic image.
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11-04-2010, 07:27 PM   #60
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QuoteOriginally posted by Feudal1 Quote
I received the Metz 58 AF-1 flash today, along with the DA* 55mm f/1.4. Took some test shots with the K-5/flash combo, and noticed some inconsistency in exposure.
Not sure if you're seeing this. But some have reported an issue with the K-5 and hotshoe flashes (an issue not known with the K-7). There is a sibling thread about it. Something like the flash always or sometimes fires with max. power.
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