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01-09-2016, 09:38 AM   #181
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QuoteOriginally posted by normhead Quote
Oh, it definitely is a normal value, and the variation between cameras is actually quite small. But from my perspective, lw/ph is probably a better evaluation of a cameras resolution than MP. Although I'm sure I once saw camera on IR that had an unexpectedly high lw/ph given it's number of MP, so it's definitely not a direct correlation.

And I'm wondering if that's how DxO comes up with their MP number.
You are right this is a better evaluation as long the measurement was done correctly and you know the procedure used. A different raw processing software,different firmware camera version, different jpeg setting in camera can all have an effect.

And you can't convert pixels into lw/ph that easily neither.

01-09-2016, 09:44 AM   #182
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Only the most naive Bayer interpolation would make 24MP (with incomplete color data) into a 6MP image; camera makers aren't doing that. So the first interpretation would be incorrect. Likewise, oversampling and interpolation are quite different.
Besides, we must be clear what we're talking about: incomplete color data i.e. pre-interpolation Bayer image? Bayer-interpolated image? Full color resolution image? Full color resolution image of a black and white test chart, or of something else? Monochrome image from a monochrome sensor, which I guess would perform the best on such test charts?

The K-3 is a typical APS-C camera with a 24MP Bayer sensor, and a slightly less than optimal JPEG engine. IMHO.
01-09-2016, 10:23 AM   #183
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Basically all (lensrentals aside) "official review sites" suck big time. That specifically includes DxO, Photozone, lenstip. Any Amazon user review gives you as much reliable information on resolution.

1)
If you consider all the massive quality control issues Sigma for example has "even" with their art line, any review based on a single sample or two is a waste. Due to poor quality control the lenses of the same type will differ more than different type lenses will on average.
So any "numbers" they generate are just BS for anyone else. And that is the case for all products from all makers.

2)
Nobody aside from real measurebation fanboys gains anything from numbers as the total visual impact needs to be felt.

-->
You get much better impression of lenses from anyone offering a full res photo taken at base ISO, stopped down 2-3 times using good daylight and a nicely textured subject, from a tripod. No need for this to be a very special test setup. No need to have the same test target for two lens shots for comparison either.
Either this type of result is satisfying or not. Completely irrelevant what numbers this translates into. Because that's what you will use it for. Pictures.
01-09-2016, 10:47 AM   #184
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QuoteOriginally posted by beholder3 Quote
Basically all (lensrentals aside) "official review sites" suck big time. That specifically includes DxO, Photozone, lenstip. Any Amazon user review gives you as much reliable information on resolution.

1)
If you consider all the massive quality control issues Sigma for example has "even" with their art line, any review based on a single sample or two is a waste. Due to poor quality control the lenses of the same type will differ more than different type lenses will on average.
So any "numbers" they generate are just BS for anyone else. And that is the case for all products from all makers.

2)
Nobody aside from real measurebation fanboys gains anything from numbers as the total visual impact needs to be felt.

-->
You get much better impression of lenses from anyone offering a full res photo taken at base ISO, stopped down 2-3 times using good daylight and a nicely textured subject, from a tripod. No need for this to be a very special test setup. No need to have the same test target for two lens shots for comparison either.
Either this type of result is satisfying or not. Completely irrelevant what numbers this translates into. Because that's what you will use it for. Pictures.
Teasing real information from the sites is kind of a hobby in it's own. You don't have to do it. But, these guys have mades some attempts to do standardized testing on these lenses, and you if you take the time to understand what they've done, you won't be mislead by their results. I find DxO results next to useless because they test in low artificial light, of the thousands of images I shoot each year, not more than 20 are taken in such circumstances, of they're rating system is not terribly relevant to me. But that doesn't mean I can't come to an understanding of what they do and use it. Same with Photozone and Imagine Resources, both of whom give you test charts results but a variety of images to evaluate as well. I actually think you learn a lot by looking at the numbers and comparing the images.

The images help you understand the numbers.

That being said, if the images and numbers have taught me anything, it's that great numbers actually make a difference over average numbers, in a very small percentage of photographs.

01-09-2016, 12:28 PM   #185
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Even the sample image are difficult to manage. ephotozine tend to go outside and always take almost the same subjects. This is nice because you can compare final picture at different focal length and apperture. Only issue is that they live in UK and the weather is often so-so. So some lens will get the easy mode a suny day with lot of contrast were any lens will be able to take some nice photos... Or you'll get the dull day with lack of contrast and color were only the best lens would make something not too bad.

Lenstip also tend to take often the same photos. Now the issue is that they use the lowest sharpening setting in the jpeg engine. On many camera this actually soften the image but anyway that setting will be different for each camera... And the sample image that you can actually download look much softer than the typical picture you would get with same lens/camera. On lenstip the best doesn't look much better than a smartphone because of the crappy settings they use.

Photozone test almost no Pentax lens theses day and at best with a K5. This is less and less interresting and if you want to compare to an older lens change are it is available in 10MP only.

I have found myself the number to be a bit of lie in cases were field curvature is involved (DA15, DA21 and most WA). In this case photozone for example focus again for the borders but that not what you would typically do on the field. There also an issue that a lens that look like it is good on an old sensor isn't that great while on the opposite a lens that look average on the same old sensor is much better on a more modern one.

Finally theses number do not speak that much of ofhter aspects like contrast/micro constrast, flare resistance, dynamic range. In the field the DA15 or even DA21 are garbage if you look only at MTF and could never justifiy to have the prime vs a zoom. But in practice the picture look better. And that what really count, isn't it?
01-09-2016, 08:27 PM   #186
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QuoteOriginally posted by Nicolas06 Quote
Even the sample image are difficult to manage. ephotozine tend to go outside and always take almost the same subjects. This is nice because you can compare final picture at different focal length and apperture. Only issue is that they live in UK and the weather is often so-so. So some lens will get the easy mode a suny day with lot of contrast were any lens will be able to take some nice photos... Or you'll get the dull day with lack of contrast and color were only the best lens would make something not too bad.

Lenstip also tend to take often the same photos. Now the issue is that they use the lowest sharpening setting in the jpeg engine. On many camera this actually soften the image but anyway that setting will be different for each camera... And the sample image that you can actually download look much softer than the typical picture you would get with same lens/camera. On lenstip the best doesn't look much better than a smartphone because of the crappy settings they use.

Photozone test almost no Pentax lens theses day and at best with a K5. This is less and less interresting and if you want to compare to an older lens change are it is available in 10MP only.

I have found myself the number to be a bit of lie in cases were field curvature is involved (DA15, DA21 and most WA). In this case photozone for example focus again for the borders but that not what you would typically do on the field. There also an issue that a lens that look like it is good on an old sensor isn't that great while on the opposite a lens that look average on the same old sensor is much better on a more modern one.

Finally theses number do not speak that much of ofhter aspects like contrast/micro constrast, flare resistance, dynamic range. In the field the DA15 or even DA21 are garbage if you look only at MTF and could never justifiy to have the prime vs a zoom. But in practice the picture look better. And that what really count, isn't it?
I've never found a lens to be sharp in lw/ph, and has low below .5 pixel Chromatic aberration to have poor contrast, micro-contrast, colour or to do anything but enhance dynamic range. Your faith that these are separate issues maybe misplaced. The reason people go with these two metrics is they tell you a lot about all those other things.

And are you back to that "primes are better" thing again? That is getting really old.

Of course, the really important things you didn't mention bokeh, you can only understand looking at images for that particular lens. There is no metric to tell you how that will work out.
01-10-2016, 02:44 AM   #187
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QuoteOriginally posted by D1N0 Quote
I like to watch picture samples to see if I like a lens, not statistics
Statistics are good. I too will also take a look at flickr and check out what people are producing in the field. Looking at samples is actually my second step after I look at resolution, CA's, Flare, distortion, AF etc etc.

---------- Post added 01-10-16 at 08:10 PM ----------

QuoteOriginally posted by Fogel70 Quote
It's difficult to say which is best as I can't find any numerical values on the graphs. And as Nikon lens was tested on a 12MP camera compared with the Canon lens tested on a 21MP camera.
Ephotozine is relatively simple. "Excellent" is basically 45lpmm. Yes no numerical value they keep that for themselves, but there are many lenses tested there which are carbon copies to the results at Lenstip. Ephotozine could do with adding "ridiculously excellent" and "Ludicrously excellent" above that on the graph, because there are lenses going off the chart there like the DA*200mm 2.8.

QuoteOriginally posted by Fogel70 Quote
The Canon and Nikon test was on FF lenses and Pentax was APS-C lenses. APS-C lenses need 1.5x on absolute resolution as FF lenses on FF camera for same resolution in image. These APS-C cameras also has smaller pixels than the FF cameras, so they would score higher lp/mm with the same lens.
I think your point has been argued before on the forum ....... I think unsuccessfully. The argument that APSC lenses have to be sharper, and that FF lenses don't have to be sharper to be as sharp as a DX lens is a canikon myth. Lenses have to optimized for digital where the airy disks corresond to the pixel pitch. Some old film lenses can do it, but there comes a point where the lose the optimum performance:


Theoretically, if you are choosing between an 85mm 1.2 or 1.4, you probably would lean to the 1.2. Yeah the edges are softer, but thats how portrait lenses perform. A 6D versus D750 is a nicer comparison as they have similar high ISO performance ...... not that I care, I'm not even interested in NIkon or Canon really.


QuoteOriginally posted by Fogel70 Quote
Do you only buy anything if it is the absolute best at everything?
Well I have bought things that weren't the absolute best and was disappointed. So I hunt out what I perceive to be great or "The Best", and I have also bought cheap crap, that does its job and I'm happy. Another person (lets say a canikon person) might look at my camera bag and laugh their a** off.

I'm just saying some silly internet widget at DXO shouldn't be used to make ANY future lens or camera purchase decisions. Then strangely enough, all roads lead to Nikon on those widgets, or almost all roads.

---------- Post added 01-10-16 at 08:28 PM ----------

QuoteOriginally posted by normhead Quote
I (or someone) once asked Klaus over at photonzone about abolsute testing of all lenses for absolute numbers not body dependant, I believe his answer was that for $150,000 he could buy a machine that would enable him to do that. My guess is, so far, no one has the $150,000 needed to out into this.
You could sit there for months and tabulate all the results at photozone and jam it in an Excel spreadsheet, and work out through math what are the absolute figures ......... like I did !

Klaus is yanking your chain and every-bodies chain. When they brought in the D7000 and K-5 tests, all of a sudden the Pentax lenses tested at horrendously low and improbable percentiles from the 10-16mp, then the comparison from 10mp to the D7000. And as far as I'm concerned the K-5 anti aliasing is sharper than a D7000. But who cares photozone is a waste of time. Those clowns tested the FA 43mm 1.9 and claimed that the lens wouldn't optically work on the K-5, but later they updated their bogus test. They were trying to claim the FA 43 was a dud lens all of a sudden for quite a few months. I then go to look at Pentax forums reviews of the 43mm 1.9 and nobody was complaining about the 43mm on a K-5. The 43mm 1.9 is a seriously sharp lens, and photozone were jealous and ticked off, so they lied.

I don't forget nasty stuff like that. If they don't like Pentax then stop testing it and writing up bogus findings.
01-10-2016, 03:57 AM   #188
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QuoteOriginally posted by Nicolas06 Quote
99.9% of reviewers review the lens on a given camera by taking picture of some test chart and then using imatest. This procedure is dependant of many factors:
- the number of MP of the sensor of course
- the low pass filter, how strong/weak it is or if there one or not.
- the processing done on the JPEG or RAW by the manufacturer regardless of the theoretical meaning of "RAW" manufacturers apply sharpening, lens corrections and so on (Sony for example).

This is the case of dpreview, photozone, lenstip, slrgear all test lenses on a given camera or set of camera. The only one I know of that use an optical test bench instead independant of any camera is lensrental. But this is the exception.

The issue is that even if the review doesn't say it, it tested the lens on a camera and so the lens was limited by the camera used. The typical reviewer also adapt its rating based on the camera. if the camera can manage 10Mp, then 2350 lw/ph is outstanding and anything that is 2000+ is good, but if the lens is tested on a 24MP without low pass filter it would need to get 3000 lw/ph to get the results. In practice not all lenses handle the increase of Mp as well and some lenses that where reviewed as great on old sensor get a reduced rating on a more modern one. This is the case of FA43 for example.

And this is also forgeting that most reviewer test only 1 sample. The 18-135 on photozone was likely a bad one for example. Sample variation in term of performance can be quite big, in particular toward border/corner. On the review website lens A might be better than lens B but if yourself buy them both you could have you own sample of B being better than your own sample of A. The example is the 20-40. Some review find it better near 20mm other near 40mm other in the middle.

What more? An innexpensive kit lens on a high rez sensor typically does better in absolute than on a lower rez sensor... But will get lower scores by the reviewer because it might not be as near to the top performance the sensor allow. Tha's stupid but that how lenses are reviewed.

You initial point was that DxO was biased for Nikon. Do you know that nowadays the lenses that are mounted on Canon that get the best sharpness score? Well that because now 5Ds is part of the test results. The 35mm f/2 that before had 20MP sharpness score on a 5D mark III just got 34MP on the 5Ds.

An you know what? All theses FF lenses pentax has will get improved score when they will be reviewed with the FF and suddenly people look a bit too fast would think Pentax make much better lens than before.

The other reviewers they still use a given camera to perform their review. What more they don't test on all cameras but on a single one they have arround that is not necessarily the latest and great. Most reviewers use camera that are 24MP or less. This is even more visible if the review is a bit old and then the cameras are 10 or 16MP...
Yeah I'm aware of all the factors, and usually they'll state that their test is accurate to within + and - such and such.

On that 43mm 1.9, Lenstip didn't have any problems testing it, and it hits peaks of 53lpmm, where as the $4000 Zeiss Otus peaks at 52lpmm (I ain't saying the 1990's design 43mm is better than a 2014 Otus). I'm saying that those reviewers probably lied out of spite towards Pentax and jealously at such a high figure. I don't know, maybe the FA 43mm 1.9 doesn't work optically on a k-5, it appears to work in the Pentax Forums lens review, and there are pictures from that combo on Flickr ........ so somebodies lying here ! and why are they ? Is it jealousy ?

01-10-2016, 04:06 AM - 1 Like   #189
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QuoteOriginally posted by normhead Quote
I've never found a lens to be sharp in lw/ph, and has low below .5 pixel Chromatic aberration to have poor contrast, micro-contrast, colour or to do anything but enhance dynamic range. Your faith that these are separate issues maybe misplaced. The reason people go with these two metrics is they tell you a lot about all those other things.
The DA35 ltd has more contrast, more punchy colors, more flare resistance (this is typically linked) than the FA77. The DA35 ltd is more constrasty, with a cooler rendering, very profound black and a bit like the DA15 it will manage to capture more dynamic range than most lenses you could find.

The FA77 is also constrasty enough starting f/3.2-f/4. It has a warm color rendering, it tend to flare quite a bit in difficult situation and would not capture the same dynamic range as the DA35 ltd or DA15 can. It has some CA issues too that can be annoying in some situations and overall the colors are less punchy than what a DA15 or DA35 do.

The DA15 is like the DA35 pushed to the extreme for contrast and micro constrast but not on the sharpness side. The border sharpness is nothing to rave about. But if you want to capture a landscape with lot of dynamic range and backlight the DA15 is king and DA35 ltd queen. FA77 is bellow average (compared to other DAltds). Oh the FA77 is going to do stuning landscapes, but only if you don't expose it too much to flare.

Each lens has its own characteristics and this you don't see on the charts. Charts would say the Samyang 16mm f/2 is sharper than the DA15 by a fair margin but none would say that the DA15 has much more constrast, dynamic range and flare resistance. But that just how it is.

Maybe you didn't look for it, maybe you are not interrested, maybe you didn't got lenses that have outstanding constrast and flare resistance like a DA15 but there for sure quite a difference.

Here an example, Same day, same hour (18H08 for the FA77, 18h15 for the DA15), same place., One case the light is comming from the left, the other from the right, other than that this is not so much different. I pushed the contrast of the FA77 much more than on the DA15 shoot: The light is not exactly the same for sure but you'll see that for one picture the rendering is all in heavy contrasts and puncy colors and for the other the whole rendering is subtle tones variations.

A part of it sure come greatly from the original scene but I would say each picture is typical as to what the lens would give.
PS: The DA15 shoot has been cropped quite a bit but I think the overall perspective and field of view would allow still anybody to recognise it.









And well I never seen the DA15 or DA35 render anything like the picture in attachment. Look all the chromatic aberation there is, even a big purple blob. But I like both the DA15 and FA77 even if the DA15 is less sharp and more contrasty. Different lenses for different purposes.

Last edited by Nicolas06; 01-31-2017 at 02:03 PM.
01-10-2016, 04:16 AM   #190
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QuoteOriginally posted by zoolander Quote
Yeah I'm aware of all the factors, and usually they'll state that their test is accurate to within + and - such and such.

On that 43mm 1.9, Lenstip didn't have any problems testing it, and it hits peaks of 53lpmm, where as the $4000 Zeiss Otus peaks at 52lpmm (I ain't saying the 1990's design 43mm is better than a 2014 Otus). I'm saying that those reviewers probably lied out of spite towards Pentax and jealously at such a high figure. I don't know, maybe the FA 43mm 1.9 doesn't work optically on a k-5, it appears to work in the Pentax Forums lens review, and there are pictures from that combo on Flickr ........ so somebodies lying here ! and why are they ? Is it jealousy ?
Or just sample variation and the border of one reviewer is not the border of the other reviewer. I assume the FA43 on ephotozine is like it should be but there quite a few bad sample lurking like the one photozone had or the OP has.
01-10-2016, 04:31 AM   #191
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QuoteOriginally posted by zoolander Quote
Statistics are good. I too will also take a look at flickr and check out what people are producing in the field. Looking at samples is actually my second step after I look at resolution, CA's, Flare, distortion, AF etc etc.

---------- Post added 01-10-16 at 08:10 PM ----------



Ephotozine is relatively simple. "Excellent" is basically 45lpmm. Yes no numerical value they keep that for themselves, but there are many lenses tested there which are carbon copies to the results at Lenstip. Ephotozine could do with adding "ridiculously excellent" and "Ludicrously excellent" above that on the graph, because there are lenses going off the chart there like the DA*200mm 2.8.

I think your point has been argued before on the forum ....... I think unsuccessfully. The argument that APSC lenses have to be sharper, and that FF lenses don't have to be sharper to be as sharp as a DX lens is a canikon myth. Lenses have to optimized for digital where the airy disks corresond to the pixel pitch. Some old film lenses can do it, but there comes a point where the lose the optimum performance:
As a FF is 24mm high and APS-C is 16mm high you get 1.5x resolving power on FF if they both measures the same in lp/mm.
FF lens with 45 lp/mm on FF camera would get 24mm * 45 line pair in total, which equals to 2160 lw/ph
APS-C lens with 45 lp/mm on APS-C camera would get 16mm * 45 line pair in total, which equals to 1440 lw/ph

As APS-C sensors usually have smaller pixels they often show higher lp/mm than a FF sensor when testing the same FF lens, but the FF will still have higher lw/ph. So images captured by FF will show better result in total. (unless the lens have very poor edge performance)

Comparing lp/mm between different sized sensors is kind of comparing pixel noise on sensor with different pixel size.
Testing FF lenses on Pentax Q would give some incredible lp/mm result.

Here is what Imatest write.
"Film camera lens tests used line pairs per millimeter (lp/mm). This worked well for comparing lenses because most 35mm film cameras have the same 24x36 mm picture size. But digital sensor sizes varies widely, from under 5 mm diagonal in camera phones to 43 mm diagonal for full-frame DSLRs— even larger for medium format backs. For this reason, Line widths per picture height (LW/PH) is recommended for measuring the total detail a camera can reproduce. LW/PH is equal to 2 * lp/mm * (picture height in mm)."
Sharpness: What is it and how is it measured? | imatest
01-10-2016, 07:08 AM   #192
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lp/mm is not a format neutral measurement, lw/ph is.

QuoteQuote:
Maybe you didn't look for it, maybe you are not interrested, maybe you didn't got lenses that have outstanding constrast and flare resistance like a DA15 but there for sure quite a difference.
Maybe everyone else thinks about those things and more, maybe you're the one on the low end of the learning curve, you always leave out all the possibilities where other people know what they are talking about, and think of all the ones where you are smarter than everyone else. Are you here to help people understand cameras systems or stroke your own ego?

But based on your response, I'm going to help me out here.

Give me an example of a lens with good flare, resistance, good micro-contrast, good contrast, good rendition etc. that doesn't have good resolution and CA values...actually look and see if what I'm saying is true, don't go blabbering on about what you look at and what I don't. No one cares about that ego nonsense.

Last edited by normhead; 01-10-2016 at 08:51 AM.
01-10-2016, 08:34 AM   #193
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It's maybe less out of subject than on the FF teaser thread but still ...
01-11-2016, 02:30 PM   #194
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QuoteOriginally posted by normhead Quote
Maybe everyone else thinks about those things and more, maybe you're the one on the low end of the learning curve, you always leave out all the possibilities where other people know what they are talking about, and think of all the ones where you are smarter than everyone else. Are you here to help people understand cameras systems or stroke your own ego?

But based on your response, I'm going to help me out here.

Give me an example of a lens with good flare, resistance, good micro-contrast, good contrast, good rendition etc. that doesn't have good resolution and CA values...actually look and see if what I'm saying is true, don't go blabbering on about what you look at and what I don't. No one cares about that ego nonsense.
DA15 exactly match your description. Read a bit the DA15 thread you'll see it is not loved for resolution. No way it match the FA77 resolution or bokeh and no way the FA77 get the same flare resistance, dynamic range, contrast and rendering. For the renderign is not even one is better they just render very differently and serve different purposes. An example of the rendering difference was provided just above, thanks. Just open your eyes; Don't see a difference then don't care. Simple as that.

You know what? If you don't see it and everybody else see it, the thing is what does it change? Why would you pay for it? And if I see the difference, nobody else see, why I woundn't benefit of it anyway? I'am not alone as many would point similar thing on many lenses reviews and so on but that's not even the point. Many don't understand why one would buy an FA ltd when a sigma provide as much for half the price.

You of course know all of this already but this would not fit your point. So you would imply that - maybe - all lenses with good rendering/constrast/flare have good resolution and ask somebody to give a counter example... Like if it was any difficult.. You know it is crap but that fit the point.

It is not like resolution wise you would explain in a thread that a D810 (30% more res) is not worth it because we don't need that many dpi. Then in another thread you would explain that 15% decrease from 50mm crop is terrible. An, APSC shoot on a FF lens is just a crop, but that must not count apparently.

It is not like we can't see you post heavily cropped pictures on this forum. Do what I say, not what I do.

Last edited by Nicolas06; 01-11-2016 at 02:48 PM.
01-16-2016, 03:29 AM   #195
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QuoteOriginally posted by Fogel70 Quote
As a FF is 24mm high and APS-C is 16mm high you get 1.5x resolving power on FF if they both measures the same in lp/mm.
FF lens with 45 lp/mm on FF camera would get 24mm * 45 line pair in total, which equals to 2160 lw/ph
APS-C lens with 45 lp/mm on APS-C camera would get 16mm * 45 line pair in total, which equals to 1440 lw/ph

As APS-C sensors usually have smaller pixels they often show higher lp/mm than a FF sensor when testing the same FF lens, but the FF will still have higher lw/ph. So images captured by FF will show better result in total. (unless the lens have very poor edge performance)

Comparing lp/mm between different sized sensors is kind of comparing pixel noise on sensor with different pixel size.
Testing FF lenses on Pentax Q would give some incredible lp/mm result.

Here is what Imatest write.
"Film camera lens tests used line pairs per millimeter (lp/mm). This worked well for comparing lenses because most 35mm film cameras have the same 24x36 mm picture size. But digital sensor sizes varies widely, from under 5 mm diagonal in camera phones to 43 mm diagonal for full-frame DSLRs— even larger for medium format backs. For this reason, Line widths per picture height (LW/PH) is recommended for measuring the total detail a camera can reproduce. LW/PH is equal to 2 * lp/mm * (picture height in mm)."
Sharpness: What is it and how is it measured? | imatest
Okay so 2160 is 33% more than 1440. So are crop camera images 33% less sharp than full frame cameras?


Although this might be considered an unfair comparison, because a. the K-3 has no AA filter b. K-3 uses pixel shift c. the Tamron lens Ed uses is not as sharp as a DA* lens. And its not like Ed buys crappy gear.

Back in the day crop had very heavy AA filters, now thery're real light or if any. Then why does it appear that crop is just as sharp as full frame, and in many cases sharper ? I mean, they're not putting on AA filters so blurry that they're taking away 33% sharpness from a FF image.
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Arrggh - Nikon V2 scores lower than V1 or RX100 on dxomark Christine Tham Non-Pentax Cameras: Canon, Nikon, etc. 36 12-24-2012 04:41 PM
DXOMark scores for the Q posted. . . snostorm Pentax Q 8 12-03-2011 01:47 PM



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