DxO reviews versus Reality

normhead · 01-16-2014, 09:42 AM

Originally posted by Rondec

I think Klaus did his best with the 18-135. He had a bad copy, but he sent it to Pentax Germany and they said that it was up to standard.

All a reviewer can do is test things and then report the data that they get. And Klaus is really transparent about where his lenses come from and his overall testing procedure.

To use that site I would totally recommend reading the 18-135 review the reading the 18-200 or other reviews of simlar lenses. What you'll see is that the only lens in it's class with excellent centre sharpness at every focal length, got the worst rating. The good thing about his site is the data is there so you can see how he came to his conclusion, and choose to decide the lens is right for you, despite his rating.

**Rondec** · 01-16-2014, 09:52 AM

Originally posted by normhead

To use that site I would totally recommend reading the 18-135 review the reading the 18-200 or other reviews of simlar lenses. What you'll see is that the only lens in it's class with excellent centre sharpness at every focal length, got the worst rating. The good thing about his site is the data is there so you can see how he came to his conclusion, and choose to decide the lens is right for you, despite his rating.

The biggest "problem" with the site is that they factor in price into their reviews. So an 18-200 that is priced at 200 dollars at the time of the review will not be reviewed as hard as an 18-135 lens that is priced at 400 dollars at the time of the review.

I can understand the perspective. The FA 50, when it was reviewed, was under 200 dollars and so got treated more gently than the DA *55, which was between 500 and 600 dollars. The problem is that if there is a price hike after the review, it can change what is really a good bargain and what isn't.

CDW · 01-16-2014, 12:38 PM - **1 Like**

I love reducing ISO noise and reducing distortion, but I wouldn't loose sleep over a 1% difference in quality!

The difference in the residual noise floor (read out noise) in shadow areas between SONY and Canon sensors is huge, but you'd never know it from the noise curves in DXO. OTOH, at very high ISOs, fine grain noise tends to be lower in the latest Canon sensors. So, depending on your application or need, a more detailed analysis would be a very handy tool as part of the decision making process.

Tarragon · 01-16-2014, 01:16 PM

Fair enough

Mind you, aren't we all supposed to be using pentax cameras here in pentax forums? Why worry about Sony and cannon??

tuco · 01-16-2014, 01:35 PM

Originally posted by Tarragon

Fair enough

Mind you, aren't we all supposed to be using pentax cameras here in pentax forums? Why worry about Sony and cannon??

Perhaps he means Sony and Canon sensors. I don't think Ricoh makes the sensors in their cameras.

Tarragon · 01-16-2014, 02:17 PM

Ahh, fair point! sorry! Isn't it a bit weird though that they all share the same sensors? Why should one manufacturer be better than the other if the sensor data is the same. It just relegates camera manufactures as box manufacturers! No innovation in the key area of photography? I suppose I daren't mention sigma at this point!!

**Rondec** · 01-16-2014, 03:08 PM - **1 Like**

Originally posted by Tarragon

Ahh, fair point! sorry! Isn't it a bit weird though that they all share the same sensors? Why should one manufacturer be better than the other if the sensor data is the same. It just relegates camera manufactures as box manufacturers! No innovation in the key area of photography? I suppose I daren't mention sigma at this point!!

Well, it is more about the glass than anything else anyway, isn't it? I don't shoot Pentax for the sensors, that's for sure...

**stevebrot** · 01-16-2014, 03:38 PM

Originally posted by normhead

What you'll see is that the only lens in it's class with excellent centre sharpness at every focal length, got the worst rating.

Did you look at his real world sample images? The off-center performance truly sucks at other than moderate focal lengths. It would seem that 30mm-60mm is the sweet spot for the lens. Does that mean I will not buy an 18-135?* It is hard to say, but you can be sure that I will definitely take a few test shots of my own before I lay any money down.

Steve

* I really want to like get this lens, but not if even a few have the kind of performance Klaus found.

**Rondec** · 01-16-2014, 03:48 PM

Originally posted by stevebrot

Did you look at his real world sample images? The off-center performance truly sucks at other than moderate focal lengths. It would seem that 30mm-60mm is the sweet spot for the lens. Does that mean I will not buy an 18-135?* It is hard to say, but you can be sure that I will definitely take a few test shots of my own before I lay any money down.

Steve

* I really want to like get this lens, but not if even a few have the kind of performance Klaus found.

Different people have found different results. Dan (audiobomber) posted some comparisons with his 18-250 and 55-300 and his copy was actually as good as either of those. I think in consumer zooms, there is probably more sample variation than with top of the line lenses.

CDW · 01-16-2014, 04:31 PM

Well, it is more about the glass than anything else anyway, isn't it? I don't shoot Pentax for the sensors, that's for sure..

That's a fair comment. I shoot in some situations where cleaness in black/dark areas is critical and the fact the K5 and now my K3, use SONY sensors is important, and particularly in view of the fact I have no interest whatsoever in SONY bodies and acquiring an entirely new crop of lenses. I'm happy enough with my two Pentax K mount lenses and using my 645 lenses with an adapter. FWIW, when I bought my K3 just before Christmas, the only 'deal' available was with the 18-135 kit lens. I took about a dozen shots with it and found it not to my liking with the K3. Edges and corners were pretty much soft throughout the range. The K3 seemed to extract all the lens was capable of in the center of the frame and that seemed quite good but by comparison the edges and corners were quite mediocre on my example.

normhead · 01-17-2014, 07:07 AM

Quote:

Did you look at his real world sample images?

Yes actually I did. I looked at the real world sample images on the forum, as well as some test images Klaus took. And I look at my real world sample images. No one seems to have this problem but Klaus. The lens is worth buying just for it's performance at 24 mm, which is it's strong point. So you have an amazing landscape lens from 20 mm to 40mm, then an amazing short telephoto from 70-135.

According to Klaus' results the 18-135 will produce the sharpest super zoom images used appropriately, of any super zoom he's tested for Pentax. But don't take my word for it, look at some real world images... in the 18-135 club. Here's some real world for you, and it looks nothing like Klaus says it should, based on his tests.

https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/179869-da-1...at-can-do.html

KDAFA · 01-19-2014, 08:16 AM

Originally posted by Rondec

Well, it is more about the glass than anything else anyway, isn't it? I don't shoot Pentax for the sensors, that's for sure...

A big +1 from me on that!

The sensor IS important of course, and it's part of the equation - goes without saying.

But Pentax glass is truly one-of-a-kind, in terms of the beautiful images they make, with that unique Pentax look/character.

I'm not overly bothered by the lab lens tests, although they have their use. But it's in the actual images captured, the real-world application, where we see that special Pentax "magic" happenin' - and in my book, that's what really matters end of the day.

ElJamoquio · 01-19-2014, 08:39 AM

Originally posted by Belnan

However real world images would seem to suggest that DxO is out to lunch.

DxO has the best analysis on the internet for camera sensors.
DxO has about the worst analysis on the internet for lenses.

A 50mm F/1.4 from 1960 with PF dozens of pixels wide, cats-eyes, unusable until f/4, etc, would always rank above a 50mm F/1.8 that's perfectly usable wide open.

ElJamoquio · 01-19-2014, 08:45 AM

Originally posted by Rondec

The biggest "problem" with the site is that they factor in price into their reviews. So an 18-200 that is priced at 200 dollars at the time of the review will not be reviewed as hard as an 18-135 lens that is priced at 400 dollars at the time of the review.

I can understand the perspective. The FA 50, when it was reviewed, was under 200 dollars and so got treated more gently than the DA *55, which was between 500 and 600 dollars. The problem is that if there is a price hike after the review, it can change what is really a good bargain and what isn't.

He notes the price in his reviews, usually references it again in the conclusions. I understand his perspective as well and agree with it. It'd probably be better if the reviews were 'auto-changed' for Pentax's price-schizophrenia but that's asking a bit much IMO.

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01-16-2014, 09:42 AM	#16
normhead Pentaxian Join Date: Jun 2007 Location: Near Algonquin Park Photos: Gallery \| Albums Posts: 40,420	Originally posted by Rondec I think Klaus did his best with the 18-135. He had a bad copy, but he sent it to Pentax Germany and they said that it was up to standard. All a reviewer can do is test things and then report the data that they get. And Klaus is really transparent about where his lenses come from and his overall testing procedure. To use that site I would totally recommend reading the 18-135 review the reading the 18-200 or other reviews of simlar lenses. What you'll see is that the only lens in it's class with excellent centre sharpness at every focal length, got the worst rating. The good thing about his site is the data is there so you can see how he came to his conclusion, and choose to decide the lens is right for you, despite his rating.

01-16-2014, 09:52 AM	#17
Rondec Loyal Site Supporter Join Date: Mar 2009 Location: Gladys, Virginia Photos: Gallery Posts: 26,080	Originally posted by normhead To use that site I would totally recommend reading the 18-135 review the reading the 18-200 or other reviews of simlar lenses. What you'll see is that the only lens in it's class with excellent centre sharpness at every focal length, got the worst rating. The good thing about his site is the data is there so you can see how he came to his conclusion, and choose to decide the lens is right for you, despite his rating. The biggest "problem" with the site is that they factor in price into their reviews. So an 18-200 that is priced at 200 dollars at the time of the review will not be reviewed as hard as an 18-135 lens that is priced at 400 dollars at the time of the review. I can understand the perspective. The FA 50, when it was reviewed, was under 200 dollars and so got treated more gently than the DA *55, which was between 500 and 600 dollars. The problem is that if there is a price hike after the review, it can change what is really a good bargain and what isn't.

01-16-2014, 12:38 PM - 1 Like	#18
CDW Site Supporter Join Date: May 2011 Location: Big Island, Hawaii & Utah Posts: 457	I love reducing ISO noise and reducing distortion, but I wouldn't loose sleep over a 1% difference in quality! The difference in the residual noise floor (read out noise) in shadow areas between SONY and Canon sensors is huge, but you'd never know it from the noise curves in DXO. OTOH, at very high ISOs, fine grain noise tends to be lower in the latest Canon sensors. So, depending on your application or need, a more detailed analysis would be a very handy tool as part of the decision making process.

01-16-2014, 01:16 PM	#19
Tarragon Junior Member Join Date: Jan 2014 Location: Lancashire Photos: Albums Posts: 48	Fair enough Mind you, aren't we all supposed to be using pentax cameras here in pentax forums? Why worry about Sony and cannon??

01-16-2014, 01:35 PM	#20
tuco Pentaxian Join Date: Jul 2009 Location: Pugetopolis Posts: 10,478	Originally posted by Tarragon Fair enough Mind you, aren't we all supposed to be using pentax cameras here in pentax forums? Why worry about Sony and cannon?? Perhaps he means Sony and Canon sensors. I don't think Ricoh makes the sensors in their cameras.

01-16-2014, 02:17 PM	#21
Tarragon Junior Member Join Date: Jan 2014 Location: Lancashire Photos: Albums Posts: 48	Ahh, fair point! sorry! Isn't it a bit weird though that they all share the same sensors? Why should one manufacturer be better than the other if the sensor data is the same. It just relegates camera manufactures as box manufacturers! No innovation in the key area of photography? I suppose I daren't mention sigma at this point!!

01-16-2014, 03:08 PM - 1 Like	#22
Rondec Loyal Site Supporter Join Date: Mar 2009 Location: Gladys, Virginia Photos: Gallery Posts: 26,080	Originally posted by Tarragon Ahh, fair point! sorry! Isn't it a bit weird though that they all share the same sensors? Why should one manufacturer be better than the other if the sensor data is the same. It just relegates camera manufactures as box manufacturers! No innovation in the key area of photography? I suppose I daren't mention sigma at this point!! Well, it is more about the glass than anything else anyway, isn't it? I don't shoot Pentax for the sensors, that's for sure...

01-16-2014, 03:38 PM	#23
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by normhead What you'll see is that the only lens in it's class with excellent centre sharpness at every focal length, got the worst rating. Did you look at his real world sample images? The off-center performance truly sucks at other than moderate focal lengths. It would seem that 30mm-60mm is the sweet spot for the lens. Does that mean I will not buy an 18-135?* It is hard to say, but you can be sure that I will definitely take a few test shots of my own before I lay any money down. Steve * I really want to like get this lens, but not if even a few have the kind of performance Klaus found.

01-16-2014, 03:48 PM	#24
Rondec Loyal Site Supporter Join Date: Mar 2009 Location: Gladys, Virginia Photos: Gallery Posts: 26,080	Originally posted by stevebrot Did you look at his real world sample images? The off-center performance truly sucks at other than moderate focal lengths. It would seem that 30mm-60mm is the sweet spot for the lens. Does that mean I will not buy an 18-135?* It is hard to say, but you can be sure that I will definitely take a few test shots of my own before I lay any money down. Steve * I really want to like get this lens, but not if even a few have the kind of performance Klaus found. Different people have found different results. Dan (audiobomber) posted some comparisons with his 18-250 and 55-300 and his copy was actually as good as either of those. I think in consumer zooms, there is probably more sample variation than with top of the line lenses.

01-16-2014, 04:31 PM	#25
CDW Site Supporter Join Date: May 2011 Location: Big Island, Hawaii & Utah Posts: 457	Well, it is more about the glass than anything else anyway, isn't it? I don't shoot Pentax for the sensors, that's for sure.. That's a fair comment. I shoot in some situations where cleaness in black/dark areas is critical and the fact the K5 and now my K3, use SONY sensors is important, and particularly in view of the fact I have no interest whatsoever in SONY bodies and acquiring an entirely new crop of lenses. I'm happy enough with my two Pentax K mount lenses and using my 645 lenses with an adapter. FWIW, when I bought my K3 just before Christmas, the only 'deal' available was with the 18-135 kit lens. I took about a dozen shots with it and found it not to my liking with the K3. Edges and corners were pretty much soft throughout the range. The K3 seemed to extract all the lens was capable of in the center of the frame and that seemed quite good but by comparison the edges and corners were quite mediocre on my example.

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01-17-2014, 07:07 AM	#26
normhead Pentaxian Join Date: Jun 2007 Location: Near Algonquin Park Photos: Gallery \| Albums Posts: 40,420	Quote: Did you look at his real world sample images? Yes actually I did. I looked at the real world sample images on the forum, as well as some test images Klaus took. And I look at my real world sample images. No one seems to have this problem but Klaus. The lens is worth buying just for it's performance at 24 mm, which is it's strong point. So you have an amazing landscape lens from 20 mm to 40mm, then an amazing short telephoto from 70-135. According to Klaus' results the 18-135 will produce the sharpest super zoom images used appropriately, of any super zoom he's tested for Pentax. But don't take my word for it, look at some real world images... in the 18-135 club. Here's some real world for you, and it looks nothing like Klaus says it should, based on his tests. https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/179869-da-1...at-can-do.html

01-19-2014, 08:16 AM	#27
KDAFA Veteran Member Join Date: Dec 2012 Posts: 523	Originally posted by Rondec Well, it is more about the glass than anything else anyway, isn't it? I don't shoot Pentax for the sensors, that's for sure... A big +1 from me on that! The sensor IS important of course, and it's part of the equation - goes without saying. But Pentax glass is truly one-of-a-kind, in terms of the beautiful images they make, with that unique Pentax look/character. I'm not overly bothered by the lab lens tests, although they have their use. But it's in the actual images captured, the real-world application, where we see that special Pentax "magic" happenin' - and in my book, that's what really matters end of the day.

01-19-2014, 08:39 AM	#28
ElJamoquio Veteran Member Join Date: Feb 2011 Posts: 4,873	Originally posted by Belnan However real world images would seem to suggest that DxO is out to lunch. DxO has the best analysis on the internet for camera sensors. DxO has about the worst analysis on the internet for lenses. A 50mm F/1.4 from 1960 with PF dozens of pixels wide, cats-eyes, unusable until f/4, etc, would always rank above a 50mm F/1.8 that's perfectly usable wide open.

01-19-2014, 08:45 AM	#29
ElJamoquio Veteran Member Join Date: Feb 2011 Posts: 4,873	Originally posted by Rondec The biggest "problem" with the site is that they factor in price into their reviews. So an 18-200 that is priced at 200 dollars at the time of the review will not be reviewed as hard as an 18-135 lens that is priced at 400 dollars at the time of the review. I can understand the perspective. The FA 50, when it was reviewed, was under 200 dollars and so got treated more gently than the DA *55, which was between 500 and 600 dollars. The problem is that if there is a price hike after the review, it can change what is really a good bargain and what isn't. He notes the price in his reviews, usually references it again in the conclusions. I understand his perspective as well and agree with it. It'd probably be better if the reviews were 'auto-changed' for Pentax's price-schizophrenia but that's asking a bit much IMO.