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10-13-2017, 07:25 PM   #61
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QuoteOriginally posted by surfar Quote


---------- Post added 10-14-17 at 06:31 AM ----------



Who would believe a word that those people say?
Not me…

They are for me a second or third option, but if others agree with them,or theirs is the only opinion on a subject I'll quote them.

You do have to read carefully to understand what they are saying. If you understand that you know how to use what they publish. But their headlinwa are pure garbage as is their rating system for overall scores.vut you can tease useful info from their numbers. As general practice I don't believe a word they say,

Are we clear on that

Some see it as a contradiction, some have the understanding to know it can be both ways.

I notice you don't have comment on the soft Fuji images at ISO 6400 pm Imagine Resources. I guess that's more reality than you can swallow. Just as I'm sure my explanation is.


Last edited by normhead; 10-13-2017 at 07:31 PM.
10-13-2017, 07:59 PM   #62
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QuoteOriginally posted by normhead Quote
I notice you don't have comment on the soft Fuji images at ISO 6400 pm Imagine Resources
I dont ever look at IM or Dxo(apart from when someone might include a link)

I will comment on some images at 6400iso from my XE3 when it arrives,could be Monday?Its only an Apsc but what ive seen it looks OK.
10-13-2017, 09:18 PM   #63
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The real reason that they are doing this is that they are soon to release the review of a new camera that has a better score than the 645Z.
Remember K5, K3, K1 reviews?
Often the reviews are out just to get them trashed by a camera that is 1.5yr or more newer.
10-14-2017, 02:54 AM   #64
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QuoteOriginally posted by Na Horuk Quote
This is pretty standard for DXo. I looked at DA 40mm SMC, HD, and XS version. On some cameras, the XS is best. On others, the HD is best. Not only do their scores change, but their ranking order changes as well.
DXo is ultimately pretty useless information. You can get better info from many other review sites, where they just test the essentials like CA, chroma, distortion, resolution, and then you decide if the results are acceptable or not. Lenstip, Photozone, various magazines, and even this forum have reviews that are good enough for most photographers.

DXo reviews imply easy ranking and objective results, but they don't actually deliver that. Many other sources give reviews that are just as valuable
I find DXO Mark's lens scores to be pretty useless. Their sensor scores seem to be better and can give some information as long as you don't read too much into them. The overall scores are pretty useless, although if they are sizable (more than 5 points) then they probably do indicate a difference that would be seen in real world shooting and processing.

What is more useful are the numbers which go into making the scores -- the base dynamic range, sports iso score, and the color depth. Frame rates and resolution are not taken into account on these scores.

What is problematic is when people make too much ado about tiny differences. Camera A has a sports iso of 3165 and Camera B has a sports iso of 2814. There is a difference of 0.4 EV of dynamic range at base iso. When I look at sensors of a similar generation I am more struck by how little difference there is between them than by the fact that there are certain ones that blow the others away.

10-15-2017, 12:32 PM   #65
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---------- Post added 10-16-17 at 06:47 AM ----------

10-15-2017, 12:57 PM   #66
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QuoteOriginally posted by surfar Quote
Excellent points made in that video Surfer. I'd add a few... in colour depth, in a finished print, the colour depth 12 bit for the K-x type cameras, 14 bit for the APS-c flagships, is not distinguishable by the human eye, and there are scientific papers as to why that is true. So in that case, the fact that you can measure a difference, doesn't mean you can see the difference. So essentially 1/3 of their ranking system is irrelevant. When I go to DxO I look at their measurement of Dynamic Range... and ISO. They do measure those things, so while the overall rankings are irrelevant, you can learn some stuff, by looking at what they actually measure, and not reading their headlines.

But their 101 ranking for the 645z based on the "sports" ranking for a usually tripod mounted 4 ps camera with not terribly fast AF is ridiculous. It's a terrible sports camera. The being said, your beloved Fuji 645 should do quite well, if they ever test it.
10-15-2017, 01:14 PM   #67
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QuoteOriginally posted by normhead Quote
your beloved Fuji 645 should do quite well, if they ever test it.
Well, its not beloved...its just a camera and personally i hate the look of it.As for them assessing it, they can due to the Bayer array,they dont have the equipment to do Xtrans(afaik).
As with every review(written or YT) its usually one persons opinion,but sometimes a panel.If theres something interesting to me,i'll look at as much as i can....BUT, the single biggest influence to me is from owners(like on PF) showing images and pointing out pros and cons(which are only opinions).

10-15-2017, 01:27 PM   #68
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QuoteOriginally posted by normhead Quote
Excellent points made in that video Surfer. I'd add a few... in colour depth, in a finished print, the colour depth 12 bit for the K-x type cameras, 14 bit for the APS-c flagships, is not distinguishable by the human eye, and there are scientific papers as to why that is true. So in that case, the fact that you can measure a difference, doesn't mean you can see the difference. So essentially 1/3 of their ranking system is irrelevant. When I go to DxO I look at their measurement of Dynamic Range... and ISO. They do measure those things, so while the overall rankings are irrelevant, you can learn some stuff, by looking at what they actually measure, and not reading their headlines.

But their 101 ranking for the 645z based on the "sports" ranking for a usually tripod mounted 4 ps camera with not terribly fast AF is ridiculous. It's a terrible sports camera. The being said, your beloved Fuji 645 should do quite well, if they ever test it.
The sports iso is misnamed. It is just the point at which SNR drops below 30 dB. Rightly or wrongly, they assume that image quality will drop once you have a higher level of noise to signal. Most of us (I think) tolerate more noise than sports iso allows in our images and have options with noise reduction, but understanding that that is where the score comes from at least it compares cameras on a level playing field.
10-16-2017, 10:44 AM   #69
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QuoteOriginally posted by Rondec Quote
The sports iso is misnamed. It is just the point at which SNR drops below 30 dB. Rightly or wrongly, they assume that image quality will drop once you have a higher level of noise to signal. Most of us (I think) tolerate more noise than sports iso allows in our images and have options with noise reduction, but understanding that that is where the score comes from at least it compares cameras on a level playing field.
Actually, they look at all three measures.

SNR >= 30 dB

DR >= 9 EV

CD >= 18 bits

Sports ISO is point where one or more of those test fails.
10-16-2017, 10:57 AM - 3 Likes   #70
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QuoteOriginally posted by normhead Quote
Excellent points made in that video Surfer. I'd add a few... in colour depth, in a finished print, the colour depth 12 bit for the K-x type cameras, 14 bit for the APS-c flagships, is not distinguishable by the human eye, and there are scientific papers as to why that is true. So in that case, the fact that you can measure a difference, doesn't mean you can see the difference. So essentially 1/3 of their ranking system is irrelevant. When I go to DxO I look at their measurement of Dynamic Range... and ISO. They do measure those things, so while the overall rankings are irrelevant, you can learn some stuff, by looking at what they actually measure, and not reading their headlines.

But their 101 ranking for the 645z based on the "sports" ranking for a usually tripod mounted 4 ps camera with not terribly fast AF is ridiculous. It's a terrible sports camera. The being said, your beloved Fuji 645 should do quite well, if they ever test it.
It may be true that the human eye cannot see the 12 bit gradations in a SOOC K-x print let a lone the 14 bit depth of newer cameras but that does mean the DXO rating of color depth is irrelevant.

Many of the most common post processing steps such as boosting the shadows, enhancing contrast, enhancing saturation, sharpening, dodging & burning, white balance transformations, color-space changes, and haze removal all chew into the raw bit depths.

That part of the ranking system is very relevant for assessing how much post-processing a given camera's images can tolerate before suffering from weird artifacts in color and tonality.
10-16-2017, 10:59 AM   #71
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QuoteOriginally posted by reh321 Quote
Actually, they look at all three measures.

SNR >= 30 dB

DR >= 9 EV

CD >= 18 bits

Sports ISO is point where one or more of those test fails.
OK. Somehow I missed that when I looked at their site, but either way it is basically a bar that they set that says "below this level images aren't adequate." Either way, it has nothing to do with sports and most folks using high iso are not doing so because they are shooting athletic events.

---------- Post added 10-16-17 at 02:17 PM ----------

QuoteOriginally posted by photoptimist Quote
It may be true that the human eye cannot see the 12 bit gradations in a SOOC K-x print let a lone the 14 bit depth of newer cameras but that does mean the DXO rating of color depth is irrelevant.

Many of the most common post processing steps such as boosting the shadows, enhancing contrast, enhancing saturation, sharpening, dodging & burning, white balance transformations, color-space changes, and haze removal all chew into the raw bit depths.

That part of the ranking system is very relevant for assessing how much post-processing a given camera's images can tolerate before suffering from weird artifacts in color and tonality.
The whole point of post processing is to flatten the image enough that it can be represented on commonly available print media or viewing media. The fact that you look at an image and the shadows look completely black doesn't mean that there isn't detail there. If you would print it straight out of camera maybe it would look that way, but if you bump the shadows a little and brighten the image and apply a digital neutral density filter then suddenly you have used a lot more of you dynamic range -- and you could actually print/view it without a problem.
10-16-2017, 11:29 AM   #72
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QuoteOriginally posted by Rondec Quote
OK. Somehow I missed that when I looked at their site, but either way it is basically a bar that they set that says "below this level images aren't adequate."
That's not what it says. The 'sports score' is just a quick way to compare where different cameras hit an arbitrarily chosen standard. For all of their measurements, they give little rules of thumb where "a difference of less than X won't be noticeable", including DR, SNR, and these combined scores. They're well aware there isn't a magic point where things go to pieces and point it out in several places, anyone walking away thinking shooting at an iso above their camera's "sports score" results in a crap image has read things into the 'sports score' that just aren't there.

Use Case Scores - DxOMark

That said, I agree "Sports Score" is a bit of a silly name, and in any case if you want to compare two cameras (using dxo's data) you're better off comparing the entire set of data they provide and not these simplified numbers.
10-16-2017, 12:05 PM - 1 Like   #73
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QuoteOriginally posted by BrianR Quote
That's not what it says. The 'sports score' is just a quick way to compare where different cameras hit an arbitrarily chosen standard. For all of their measurements, they give little rules of thumb where "a difference of less than X won't be noticeable", including DR, SNR, and these combined scores. They're well aware there isn't a magic point where things go to pieces and point it out in several places, anyone walking away thinking shooting at an iso above their camera's "sports score" results in a crap image has read things into the 'sports score' that just aren't there.

Use Case Scores - DxOMark

That said, I agree "Sports Score" is a bit of a silly name, and in any case if you want to compare two cameras (using dxo's data) you're better off comparing the entire set of data they provide and not these simplified numbers.
Sure. I think I agree. You can shoot sports with significantly less dynamic range than 9 EVs and less SNR than 30 dBs. Landscapes and portraits are a different story, but regardless as long as it is the same standard for every camera then you have a level playing field to compare them. I think for most purposes, most of us can tolerate images that are a stop to a stop and a half higher than their sports scores (at least with a little noise reduction).
10-16-2017, 04:47 PM   #74
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QuoteOriginally posted by photoptimist Quote
That part of the ranking system is very relevant for assessing how much post-processing a given camera's images can tolerate before suffering from weird artifacts in color and tonality.
You would think that, but there's no definitive info I've seen that provides examples of that being true. I tend to go with what I see demonstrated, and stay clear of the theoretical. There's a difference between theoretical concept, and a practical theoretical concept.
10-26-2017, 06:25 AM   #75
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Now they published the Hasselblad but still no 645z Hasselblad X1D-50c Sensor Review: Best commercially-available medium-format sensor - DxOMark
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