Pages: [1] 2 3 ... 8   Go Down

Author Topic: Phase One Trichromatic In Depth Article with Raw Files  (Read 10424 times)

Doug Peterson

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 3719
    • http://www.doug-peterson.com
Phase One Trichromatic In Depth Article with Raw Files
« on: October 20, 2017, 04:31:02 PM »

I've just completed a 7000-word two-part technical article on the new Phase One IQ3 100mp Trichromatic covering the following topics:
  • Why the launch marketing materials could easily confuse reader about what improvements were made
  • An intro to color science for those that might need a refresher
  • Behind-the-scenes information on the relationship between Phase One and Sony
  • WHAT specific improvements were made
  • HOW those specific improvements manifest in real world images
  • DOWNLOADABLE raw file comparisons of the IQ3 100mp and IQ3 100mp Trichromatic

You can read that two-part article here:

Want to play with a Trichromatic yourself?
« Last Edit: October 20, 2017, 04:37:18 PM by Doug Peterson »
Logged

E.J. Peiker

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 735
    • http://www.ejphoto.com
Re: Phase One Trichromatic In Depth Article with Raw Files
« Reply #1 on: October 20, 2017, 05:50:46 PM »

Thanks for taking the time to do this.  The whole thing makes a ton of sense now where before, based on P1's initial marketing, it really made no sense at all.
Logged

BernardLanguillier

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 10782
    • http://www.flickr.com/photos/bernardlanguillier/sets/
Re: Phase One Trichromatic In Depth Article with Raw Files
« Reply #2 on: October 20, 2017, 06:07:02 PM »

Thanks for the informative read.

Cheers,
Bernard

engardeknave

  • Newbie
  • *
  • Offline Offline
  • Posts: 7
    • Jason Jared Photography
Re: Phase One Trichromatic In Depth Article with Raw Files
« Reply #3 on: October 20, 2017, 07:36:15 PM »

I uttered several expletives to myself moving those sliders around. I have been fighting these color discrepancies my entire career, all the time wondering if I'm insane, if it's all in my head.
Logged

araucaria

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 59
Re: Phase One Trichromatic In Depth Article with Raw Files
« Reply #4 on: October 21, 2017, 04:42:37 AM »

I'm far from being able to spend 40.000$ on a camera, this makes me wonder if it's really not possible to remove UV peaks with a simple filter, I'm shure there is a knowable member that could detail the reasons behind this impossibility stated in the article. I really want to get rid of the magenta skies without post processing.
Logged

Paul2660

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 3714
    • Photos of Arkansas
Re: Phase One Trichromatic In Depth Article with Raw Files
« Reply #5 on: October 21, 2017, 07:46:40 AM »

Kudos to Doug for the article, very well written.

Considering the fact that a Magenta sky in C1 can be handled quickly and easily with a simple adjustment layer with a slight hue tweak, (something I do often), even a solid blue as shown in the example, the cost of an upgrade to such a back is decidedly a bit hard to justify.   C1 makes this so easy with their existing color tools.


The fact that the trichromatic does seem to handle tech camera movements better, with less color shift is a positive feature for sure and the example of lower color noise was most impressive.

There is quite a bit of mention that the gain in such color correctness has been done at the expensive of the ISO gain, as the base ISO is now 35.  I am wondering if the higher ISO response of this back is the same as the older IQ3100, or if one is to expect about 1 stop of less gain throughout the ISO range.  This would mean that for the gain in color, one will loss a higher ISO response, just curious if that is the case or not.

Also curious as to when Sony will introduce similar CFA design to their own cameras.

2018 promises to be a great year for new products as the new chips will all be out by then.

Paul Caldwell
Logged
Paul Caldwell
Little Rock, Arkansas U.S.

ErikKaffehr

  • Sr. Member
  • ****
  • Online Online
  • Posts: 10823
    • Echophoto
Hi - lot of questionable info in that article
« Reply #6 on: October 21, 2017, 08:15:15 AM »

Hi,

Doug's posting is not a scientific article but it does contain some alternate facts.

Doug shows a spectral plot of traditional CFA filters:


But, traditional filters look like this:


Or this:


Or this:


So Doug illustrates traditional CFA designs with fake info. There is a sensor that has some characteristics similar to the traditional CFA illustration in Doug's presentation and that is the human vision, corresponding to curve A, below:


The reason such curves are not used in digital cameras is that it would cause excessive levels of noise.

Regarding UV-filtering and IR filtering, that is really a job for the cover glass, that has an IR-filter. Optical glass doesn't transmit much in UV anyway. If UV/IR is an issue, it is not about a new design, it is about Phase One designing an underperforming cover glass on the older models.

The colour differences Doug demonstrate are well within the capabilities of properly designed camera profiles. The effects shown can possibly achieved just buying a proper test target and use Lumariver's Profile Designer.

So, my impression is that it is a marketing hyperbole. The curves that Doug shows are patently fake. If the article starts with fake facts, why would be believe the rest?

To Dougs's defense, I would assume that he just uses info he got from Phase One, but I don't think he should have use it as to much of the info is fake and it should be obvious to anyone doing colour stuff.

Best regards
Erik
« Last Edit: October 21, 2017, 08:26:35 AM by ErikKaffehr »
Logged
Erik Kaffehr
 

Doug Peterson

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 3719
    • http://www.doug-peterson.com
Re: Phase One Trichromatic In Depth Article with Raw Files
« Reply #7 on: October 21, 2017, 08:53:08 AM »

There is quite a bit of mention that the gain in such color correctness has been done at the expensive of the ISO gain, as the base ISO is now 35.  I am wondering if the higher ISO response of this back is the same as the older IQ3100, or if one is to expect about 1 stop of less gain throughout the ISO range.  This would mean that for the gain in color, one will loss a higher ISO response, just curious if that is the case or not.

I've added an image comparison at ISO12,800 which you'll find under "What About the ISO Range?" in part 2.

Generally: slightly more luminance noise, less color noise.
Logged

Doug Peterson

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 3719
    • http://www.doug-peterson.com
Re: Phase One Trichromatic In Depth Article with Raw Files
« Reply #8 on: October 21, 2017, 08:56:01 AM »

I'm far from being able to spend 40.000$ on a camera, this makes me wonder if it's really not possible to remove UV peaks with a simple filter, I'm shure there is a knowable member that could detail the reasons behind this impossibility stated in the article. I really want to get rid of the magenta skies without post processing.

A UV filter in front of the lens can help with some of these issues for some cameras. But in many cases slight color contamination can be caused by near UV light (light that is still inside the visible spectrum) leaking into blue pixels or green pixels which have unintended (if slight) response outside their intended range.
Logged

Doug Peterson

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 3719
    • http://www.doug-peterson.com
Re: Phase One Trichromatic In Depth Article with Raw Files
« Reply #9 on: October 21, 2017, 08:56:28 AM »

Thanks for taking the time to do this.  The whole thing makes a ton of sense now where before, based on P1's initial marketing, it really made no sense at all.

Thanks for the informative read.

Thanks for taking the time to read!
Logged

ErikKaffehr

  • Sr. Member
  • ****
  • Online Online
  • Posts: 10823
    • Echophoto
Re: Phase One Trichromatic In Depth Article with Raw Files
« Reply #10 on: October 21, 2017, 09:05:43 AM »

Hi,

I think Phase One could just suggest a proper UV-filter to use with their cameras instead of charging them a 40k$US for a new back. It can also be argued that they could have a proper cover glass design from the beginning.

the whole story has some smell to it, it stinks.

Best regards
Erik

A UV filter in front of the lens can help with some of these issues for some cameras. But in many cases slight color contamination can be caused by near UV light (light that is still inside the visible spectrum) leaking into blue pixels or green pixels which have unintended (if slight) response outside their intended range.
Logged
Erik Kaffehr
 

Doug Peterson

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 3719
    • http://www.doug-peterson.com
Re: Hi - lot of questionable info in that article
« Reply #11 on: October 21, 2017, 09:14:41 AM »

Hi,

Doug's posting is not a scientific article but it does contain some alternate facts.

Doug shows a spectral plot of traditional CFA filters:
[image]

But, traditional filters look like this:
[image]
[...]

So, my impression is that it is a marketing hyperbole. The curves that Doug shows are patently fake. If the article starts with fake facts, why would be believe the rest?

Erik, the article starts with: "If you came to this two-part article hoping for a PhD dissertation on color science you’ll be disappointed. I do not hold a PhD in color science, nor do many of our clients. If you’re hoping this article will contain precise 10nm-sliced spectral transmission curves generated by a monochromator, along with associated data tables, then you'll be disappointed. Phase One is a for-profit company, not an academic institution, so publishing those curves would be giving away many man-years worth of accumulated experience. Personally, I won’t shed tears over either of these omissions; in my experience neither PhD dissertation nor highly detailed Spectral Transmission Data is of all that much value to a photographer deciding which equipment is the best fit to their needs and budget."

I've now added, per your post the additional sentence: "This will include illustrations of spectral transmission that are meant as a learning aid; these are crudely drawn and exaggerate differences to make them easier to consume, and should not be taken literally, but for those not steeped in scientific measurements of spectral transmission they will help visualize relevant improvements."

The spectral charts are simplified and exaggerated and only there to help visualize the improvements. They are absolutely "fake" as you say.

Simply put, you are not the target for the article, and are not the average user. If you're interested in more formal scientific information I can offer any of the following to you:
  • The use of an IQ3 100 Trichromatic at our NY or LA office for your own testing
  • A loan of an IQ3 100 Trichromatic anywhere in the US (insurance required)
  • The report by the color scientist at Library of Congress who will be testing the Trichromatic in a couple months
  • The contact information for the color science team at Phase One. If you can demonstrate a valid need, they may be able to provide you more detail under NDA.
 
Please [email protected] if you're interested in the above.

The colour differences Doug demonstrate are well within the capabilities of properly designed camera profiles. The effects shown can possibly achieved just buying a proper test target and use Lumariver's Profile Designer.

I don't agree with this. Having shot a lot of these problematic materials, and being quite familiar with profiling (e.g. I co-wrote The The Color Guide for our Cultural Heritage Division) I can say without questions that no profiling software in the world can fully address their quirks with a standard camera, at least not without sacrificing or creating problems somewhere else.
« Last Edit: October 21, 2017, 09:19:37 AM by Doug Peterson »
Logged

Doug Peterson

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 3719
    • http://www.doug-peterson.com
Re: Phase One Trichromatic In Depth Article with Raw Files
« Reply #12 on: October 21, 2017, 09:19:06 AM »

the whole story has some smell to it, it stinks.

I hope you have a chance at some point to work with and test an IQ3 100mp Trichromatic. I think it would change your mind.
Logged

ErikKaffehr

  • Sr. Member
  • ****
  • Online Online
  • Posts: 10823
    • Echophoto
Re: Hi - lot of questionable info in that article
« Reply #13 on: October 21, 2017, 09:20:10 AM »

Hi Doug,

Thanks for the change, but the information is still fake. Just saying that the curves are for illustration does not change the fact they are fake.

Reminds me of that guy sitting in that white house in Washington DC.

Best regards
Erik



I've now added, per your post the additional sentence: "This will include illustrations of spectral transmission that are meant as a learning aid; these are crudely drawn and exaggerate differences to make them easier to consume, and should not be taken literally, but for those not steeped in scientific measurements of spectral transmission they will help visualize relevant improvements."

The spectral charts are simplified and exaggerated and only there to help visualize the improvements. They are absolutely "fake" as you say.


Logged
Erik Kaffehr
 

Doug Peterson

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 3719
    • http://www.doug-peterson.com
Re: Hi - lot of questionable info in that article
« Reply #14 on: October 21, 2017, 09:59:22 AM »

Thanks for the change, but the information is still fake. Just saying that the curves are for illustration does not change the fact they are fake.

Reminds me of that guy sitting in that white house in Washington DC.

Traditional CFAs (as the ones you posted show) often:
- Leak red (and sometimes green) in the 400-500nm near-UV range (look at your own charts). It's not a lot and our graph exaggerates it to make it clear.
- Err a bit on the side of too much overlap, prioritizing ISO over better color.
- Leak green and blue in the 600-700 near-IR range. Again, our graphs exaggerate it to increase clarity.

Note that the illustration of the spectrum we used is not of any one specific traditional CFA camera. Not every traditional CFA has every issue it illustrates.

Here from MaxMax measurements for three dSLRs without IR-cut filter in place, compared to the illustration we provided:





Note that I've used the words "near UV" and "near IR" a couple times here and in the article to refer to the outer most range within the visible spectrum.  In more scientific terms this would normally refer to the area immediately below and above visible light. That's probably a faux pas on my part. But again, scientists are not the target for this article. And this thread illustrates why: scientists tend to get caught a bit in the nitty-gritty scientific details, which is great for research, but a bit stuttering for normal photographers wanting information to help make purchasing decisions.
« Last Edit: October 21, 2017, 10:20:19 AM by Doug Peterson »
Logged

sandymc

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 337
Re: Phase One Trichromatic In Depth Article with Raw Files
« Reply #15 on: October 21, 2017, 10:13:12 AM »

Personally, I would be interested in seeing a more scientific take on what the spectral responses etc, are. With labels on the Y axis. ;)  And a clear understanding of whether we're talking a sensor with cover glass, or "naked", etc. I understand that that I (or Erik) are hardly your target market, but look at it this way: not clearly laying out what the advantages of the product are can only generate controversy (see above), which won't help sales.

Sandy
Logged

ErikKaffehr

  • Sr. Member
  • ****
  • Online Online
  • Posts: 10823
    • Echophoto
Re: Hi - lot of questionable info in that article
« Reply #16 on: October 21, 2017, 10:20:20 AM »

Hi Doug,

I am not a scientist, just an engineer working in reactor physics.

But both engineers and scientist prefer facts instead of fake data. Artist have artistic freedom, engineers don't. Anyway, once you mispresent facts, your credibility goes to zero. Making mistakes is OK, if you acknowledge. Passing on fake information is not.

Best regards
Erik

Traditional CFAs (as the ones you posted show) often:
- Leak red (and sometimes green) in the 400-500nm near-UV range (look at your own charts). It's not a lot and our graph exaggerates it to make it clear.
- Err a bit on the side of too much overlap, prioritizing ISO over better color.
- Leak green and blue in the 600-700 near-IR range. Again, our graphs exaggerate it to increase clarity.

Note that the illustration of the spectrum we used is not of any one specific traditional CFA camera. Not every traditional CFA has every issue it illustrates.

Here from MaxMax measurements for three dSLRs without IR-cut filter in place, compared to the illustration we provided:





Note that I've used the words "near UV" and "near IR" a couple times here and in the article to refer to the outside range of the visible spectrum.  In more scientific terms this would normally refer to the area immediately below and above visible light. That's probably a faux pas on my part. But again, scientists are not the target for this article. And this thread illustrates why: scientists tend to get caught a bit in the pedantic weeds.
Logged
Erik Kaffehr
 

Doug Peterson

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 3719
    • http://www.doug-peterson.com
Re: Phase One Trichromatic In Depth Article with Raw Files
« Reply #17 on: October 21, 2017, 10:36:02 AM »

Personally, I would be interested in seeing a more scientific take on what the spectral responses etc, are. With labels on the Y axis. ;)

So would Phase One's competitors :).

The general gist of the types of changes made and why is as good as you'll get without an NDA.

not clearly laying out what the advantages of the product are can only generate controversy (see above), which won't help sales.

The advantages aren't the spectral curves; those are a means to the end.

The advantage is the color the camera produces. For that raw files, comparative tests, and the availablity of the camera for testing by prospective buyers are all far more useful than charts. We provide all of those.
Logged

Paul2660

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 3714
    • Photos of Arkansas
Re: Phase One Trichromatic In Depth Article with Raw Files
« Reply #18 on: October 21, 2017, 10:36:16 AM »

Hi Doug,

thanks for the comparison on the high ISO.  That being it was taken at 12K, it's an interesting comparison as the non Trich back has more details IMO, but for sure the Trich back has more shadow recovery.  Odds are in the 400 to 1600 range, where I would be shooting the new back will have overall an advantage and for sure at base ISO, the Trichromatic will have an advantage in shadow recovery. 


Paul Caldwell



Logged
Paul Caldwell
Little Rock, Arkansas U.S.

Doug Peterson

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 3719
    • http://www.doug-peterson.com
Re: Phase One Trichromatic In Depth Article with Raw Files
« Reply #19 on: October 21, 2017, 10:44:40 AM »

thanks for the comparison on the high ISO.  That being it was taken at 12K, it's an interesting comparison as the non Trich back has more details IMO, but for sure the Trich back has more shadow recovery.  Odds are in the 400 to 1600 range, where I would be shooting the new back will have overall an advantage and for sure at base ISO, the Trichromatic will have an advantage in shadow recovery. 

I'll have to look back at the files, as there may be a very slight difference in focus; I don't see any reason why there would be a change in absolute detail.
Logged
Pages: [1] 2 3 ... 8   Go Up