Re: OT Purple fringing explanation
P.J. Are you are on the fringe and turning purple? Then it's the right cure! ;-) Now, seriously: I didn't have a chance to listen to the video Rob posted (I am at a conference all day today). I think the explanation that you referenced/mentioned in the other message makes sense. Your situation with multi-pixel fringing is indeed puzzling. I wonder if it is somehow related to how the optics coating is done. Here is my guess based on the knowledge of physics of optics. And, sorry, it is still somewhat vague, as I don't have a complete scenario. Typically, the antireflection (AR) coating is tuned to a particular wavelength, or a set of those, not the entire spectrum. AFAIK, it is the centered in the yellow-green part of the spectrum, which is where the majority of the daylight is. (That's the reason why you see purple reflection when your look at the lense.) Now, that can change the balance between the amount of light that comes through that lense in the yellow-green part of the spectrum relative to that in red and blue parts of the spectrum. This would in turn contribute to the disbalance due to what you described about the compensation/balance between the green and red-blue pixels. This may explain why certain lenses are more prone to this effect than others, - due to the difference in the AR coating. Now, why can it be several pixels wide? I am guessing that in some cases, the edge of the image feature is more than one (more exactly four in the Bayer pattern) pixel wide. And if the contrast is high, it means that there is a high light intensity gradient that happens over several pixels. (You don't need to have highlights blown out, just a disbalance.) Hence, the multi-pixel purple fringing. If my guess is right, how this effect shows should depend on the object boundaries (broad or narrow, relative to the magnification [read: pixel size]) and the lighting condition (light contrast). I am looking forward to listening tonight to the video's explanation. Igor Mon Oct 6 23:01:28 EDT 2014 P.J. Alling wrote: It's nothing that a couple of aspirin and a shot of whiskey won't cure... Really not a problem at all... On 10/6/2014 8:23 PM, Rob Studdert wrote: PJ has a purple fringing problem? How unfortunate :( -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: OT Purple fringing explanation
It's nothing that a couple of aspirin and a shot of whiskey won't cure... Really not a problem at all... On 10/6/2014 8:23 PM, Rob Studdert wrote: PJ has a purple fringing problem? How unfortunate :( On 7 October 2014 11:19, Darren Addy wrote: Well, I zoomed to the 29 minute mark. I don't think his explanation really applies in the case of P.J.s photo because I don't think the fringing is in front of the plane of focus. It is just around the transition area of white (to darker). I'm sure that if Zeiss would send P.J. an Otus 85mm for use on his K-5II he would be happy to try to see if it makes the problem go away, however. Sadly, it is only currently preorderable (is that a word?) for Nikon/Canon. It is still possible that it is an artifact of post-processing. A question for P.J. I'm assuming, P.J. that you see it in the RAW files also, before processing or compression? I've seen some derogatory comments on the web about purple fringing being an issue commonly known (as in, a given) regarding Sony sensors. No idea if that is mularkey or not - or was possibly true at some times and not others? On Mon, Oct 6, 2014 at 7:06 PM, Darren Addy wrote: The first time I tried watching that video (a week or so ago) it literally put me to sleep, in the middle. I'll have to give it another try in the morning when I am full of caffeine. On Mon, Oct 6, 2014 at 6:42 PM, Rob Studdert wrote: Hi Guys, As much as I don't like Matt this video where he interviews Dr Hubert Nasse from Zeiss contains some interesting info (and displays Matt's ignorance of even basic optics) particularly at around 29 mins where there is an explanation of the reason that purple fringing occurs when using old fast optics. https://www.youtube.com/watch?v=9cnEnRADDLo Cheers, -- Rob Studdert (Digital Image Studio) Tel: +61-418-166-870 UTC +10 Hours Gmail, eBay, Skype, Twitter, Facebook, Picasa: distudio -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- Photographers must learn not to be ashamed to have their photographs look like photographs. ~ Alfred Stieglitz -- Photographers must learn not to be ashamed to have their photographs look like photographs. ~ Alfred Stieglitz -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- I don't want to achieve immortality through my work; I want to achieve immortality through not dying. -- Woody Allen -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: OT Purple fringing explanation
The fringing is in the sample Jpeg imbedded in the file, and in the images rendered by both Adobe Bridge and PDCU, so if it was in the processing it's also in the processing in the cameras Jpeg engine. I read a reason for it being purple having to do with the fact that the color demosaicing algorithm biasing towards the red and blue to make up for there being two green for every red and blue pair of photo sites, (otherwise it will bias green), it makes a certain amount of sense where there's a sharp edge, and the highlights are at the cusp of being over exposed. I've seen enough red/blue fringing in digital files, I've got at least one lens where the fringing is several pixels in width. This doesn't seem to be that at all. On 10/6/2014 8:19 PM, Darren Addy wrote: Well, I zoomed to the 29 minute mark. I don't think his explanation really applies in the case of P.J.s photo because I don't think the fringing is in front of the plane of focus. It is just around the transition area of white (to darker). I'm sure that if Zeiss would send P.J. an Otus 85mm for use on his K-5II he would be happy to try to see if it makes the problem go away, however. Sadly, it is only currently preorderable (is that a word?) for Nikon/Canon. It is still possible that it is an artifact of post-processing. A question for P.J. I'm assuming, P.J. that you see it in the RAW files also, before processing or compression? I've seen some derogatory comments on the web about purple fringing being an issue commonly known (as in, a given) regarding Sony sensors. No idea if that is mularkey or not - or was possibly true at some times and not others? On Mon, Oct 6, 2014 at 7:06 PM, Darren Addy wrote: The first time I tried watching that video (a week or so ago) it literally put me to sleep, in the middle. I'll have to give it another try in the morning when I am full of caffeine. On Mon, Oct 6, 2014 at 6:42 PM, Rob Studdert wrote: Hi Guys, As much as I don't like Matt this video where he interviews Dr Hubert Nasse from Zeiss contains some interesting info (and displays Matt's ignorance of even basic optics) particularly at around 29 mins where there is an explanation of the reason that purple fringing occurs when using old fast optics. https://www.youtube.com/watch?v=9cnEnRADDLo Cheers, -- Rob Studdert (Digital Image Studio) Tel: +61-418-166-870 UTC +10 Hours Gmail, eBay, Skype, Twitter, Facebook, Picasa: distudio -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- Photographers must learn not to be ashamed to have their photographs look like photographs. ~ Alfred Stieglitz -- I don't want to achieve immortality through my work; I want to achieve immortality through not dying. -- Woody Allen -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: OT Purple fringing explanation
Ah, I assumed you were referring to our earlier thread. Apologies. On Mon, Oct 6, 2014 at 7:23 PM, Rob Studdert wrote: > PJ has a purple fringing problem? How unfortunate :( > > On 7 October 2014 11:19, Darren Addy wrote: >> Well, I zoomed to the 29 minute mark. I don't think his explanation >> really applies in the case of P.J.s photo because I don't think the >> fringing is in front of the plane of focus. It is just around the >> transition area of white (to darker). I'm sure that if Zeiss would >> send P.J. an Otus 85mm for use on his K-5II he would be happy to try >> to see if it makes the problem go away, however. Sadly, it is only >> currently preorderable (is that a word?) for Nikon/Canon. >> >> It is still possible that it is an artifact of post-processing. >> A question for P.J. >> I'm assuming, P.J. that you see it in the RAW files also, before >> processing or compression? >> >> I've seen some derogatory comments on the web about purple fringing >> being an issue commonly known (as in, a given) regarding Sony sensors. >> No idea if that is mularkey or not - or was possibly true at some >> times and not others? >> >> >> >> On Mon, Oct 6, 2014 at 7:06 PM, Darren Addy wrote: >>> The first time I tried watching that video (a week or so ago) it >>> literally put me to sleep, in the middle. >>> I'll have to give it another try in the morning when I am full of caffeine. >>> >>> On Mon, Oct 6, 2014 at 6:42 PM, Rob Studdert >>> wrote: Hi Guys, As much as I don't like Matt this video where he interviews Dr Hubert Nasse from Zeiss contains some interesting info (and displays Matt's ignorance of even basic optics) particularly at around 29 mins where there is an explanation of the reason that purple fringing occurs when using old fast optics. https://www.youtube.com/watch?v=9cnEnRADDLo Cheers, -- Rob Studdert (Digital Image Studio) Tel: +61-418-166-870 UTC +10 Hours Gmail, eBay, Skype, Twitter, Facebook, Picasa: distudio -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. >>> >>> >>> >>> -- >>> Photographers must learn not to be ashamed to have their photographs >>> look like photographs. >>> ~ Alfred Stieglitz >> >> >> >> -- >> Photographers must learn not to be ashamed to have their photographs >> look like photographs. >> ~ Alfred Stieglitz >> >> -- >> PDML Pentax-Discuss Mail List >> PDML@pdml.net >> http://pdml.net/mailman/listinfo/pdml_pdml.net >> to UNSUBSCRIBE from the PDML, please visit the link directly above and >> follow the directions. > > > > -- > Rob Studdert (Digital Image Studio) > Tel: +61-418-166-870 UTC +10 Hours > Gmail, eBay, Skype, Twitter, Facebook, Picasa: distudio > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- Photographers must learn not to be ashamed to have their photographs look like photographs. ~ Alfred Stieglitz -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: OT Purple fringing explanation
PJ has a purple fringing problem? How unfortunate :( On 7 October 2014 11:19, Darren Addy wrote: > Well, I zoomed to the 29 minute mark. I don't think his explanation > really applies in the case of P.J.s photo because I don't think the > fringing is in front of the plane of focus. It is just around the > transition area of white (to darker). I'm sure that if Zeiss would > send P.J. an Otus 85mm for use on his K-5II he would be happy to try > to see if it makes the problem go away, however. Sadly, it is only > currently preorderable (is that a word?) for Nikon/Canon. > > It is still possible that it is an artifact of post-processing. > A question for P.J. > I'm assuming, P.J. that you see it in the RAW files also, before > processing or compression? > > I've seen some derogatory comments on the web about purple fringing > being an issue commonly known (as in, a given) regarding Sony sensors. > No idea if that is mularkey or not - or was possibly true at some > times and not others? > > > > On Mon, Oct 6, 2014 at 7:06 PM, Darren Addy wrote: >> The first time I tried watching that video (a week or so ago) it >> literally put me to sleep, in the middle. >> I'll have to give it another try in the morning when I am full of caffeine. >> >> On Mon, Oct 6, 2014 at 6:42 PM, Rob Studdert wrote: >>> Hi Guys, >>> >>> As much as I don't like Matt this video where he interviews Dr Hubert >>> Nasse from Zeiss contains some interesting info (and displays Matt's >>> ignorance of even basic optics) particularly at around 29 mins where >>> there is an explanation of the reason that purple fringing occurs when >>> using old fast optics. >>> >>> https://www.youtube.com/watch?v=9cnEnRADDLo >>> >>> Cheers, >>> >>> -- >>> Rob Studdert (Digital Image Studio) >>> Tel: +61-418-166-870 UTC +10 Hours >>> Gmail, eBay, Skype, Twitter, Facebook, Picasa: distudio >>> >>> -- >>> PDML Pentax-Discuss Mail List >>> PDML@pdml.net >>> http://pdml.net/mailman/listinfo/pdml_pdml.net >>> to UNSUBSCRIBE from the PDML, please visit the link directly above and >>> follow the directions. >> >> >> >> -- >> Photographers must learn not to be ashamed to have their photographs >> look like photographs. >> ~ Alfred Stieglitz > > > > -- > Photographers must learn not to be ashamed to have their photographs > look like photographs. > ~ Alfred Stieglitz > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- Rob Studdert (Digital Image Studio) Tel: +61-418-166-870 UTC +10 Hours Gmail, eBay, Skype, Twitter, Facebook, Picasa: distudio -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: OT Purple fringing explanation
Well, I zoomed to the 29 minute mark. I don't think his explanation really applies in the case of P.J.s photo because I don't think the fringing is in front of the plane of focus. It is just around the transition area of white (to darker). I'm sure that if Zeiss would send P.J. an Otus 85mm for use on his K-5II he would be happy to try to see if it makes the problem go away, however. Sadly, it is only currently preorderable (is that a word?) for Nikon/Canon. It is still possible that it is an artifact of post-processing. A question for P.J. I'm assuming, P.J. that you see it in the RAW files also, before processing or compression? I've seen some derogatory comments on the web about purple fringing being an issue commonly known (as in, a given) regarding Sony sensors. No idea if that is mularkey or not - or was possibly true at some times and not others? On Mon, Oct 6, 2014 at 7:06 PM, Darren Addy wrote: > The first time I tried watching that video (a week or so ago) it > literally put me to sleep, in the middle. > I'll have to give it another try in the morning when I am full of caffeine. > > On Mon, Oct 6, 2014 at 6:42 PM, Rob Studdert wrote: >> Hi Guys, >> >> As much as I don't like Matt this video where he interviews Dr Hubert >> Nasse from Zeiss contains some interesting info (and displays Matt's >> ignorance of even basic optics) particularly at around 29 mins where >> there is an explanation of the reason that purple fringing occurs when >> using old fast optics. >> >> https://www.youtube.com/watch?v=9cnEnRADDLo >> >> Cheers, >> >> -- >> Rob Studdert (Digital Image Studio) >> Tel: +61-418-166-870 UTC +10 Hours >> Gmail, eBay, Skype, Twitter, Facebook, Picasa: distudio >> >> -- >> PDML Pentax-Discuss Mail List >> PDML@pdml.net >> http://pdml.net/mailman/listinfo/pdml_pdml.net >> to UNSUBSCRIBE from the PDML, please visit the link directly above and >> follow the directions. > > > > -- > Photographers must learn not to be ashamed to have their photographs > look like photographs. > ~ Alfred Stieglitz -- Photographers must learn not to be ashamed to have their photographs look like photographs. ~ Alfred Stieglitz -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: OT Purple fringing explanation
The first time I tried watching that video (a week or so ago) it literally put me to sleep, in the middle. I'll have to give it another try in the morning when I am full of caffeine. On Mon, Oct 6, 2014 at 6:42 PM, Rob Studdert wrote: > Hi Guys, > > As much as I don't like Matt this video where he interviews Dr Hubert > Nasse from Zeiss contains some interesting info (and displays Matt's > ignorance of even basic optics) particularly at around 29 mins where > there is an explanation of the reason that purple fringing occurs when > using old fast optics. > > https://www.youtube.com/watch?v=9cnEnRADDLo > > Cheers, > > -- > Rob Studdert (Digital Image Studio) > Tel: +61-418-166-870 UTC +10 Hours > Gmail, eBay, Skype, Twitter, Facebook, Picasa: distudio > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- Photographers must learn not to be ashamed to have their photographs look like photographs. ~ Alfred Stieglitz -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
OT Purple fringing explanation
Hi Guys, As much as I don't like Matt this video where he interviews Dr Hubert Nasse from Zeiss contains some interesting info (and displays Matt's ignorance of even basic optics) particularly at around 29 mins where there is an explanation of the reason that purple fringing occurs when using old fast optics. https://www.youtube.com/watch?v=9cnEnRADDLo Cheers, -- Rob Studdert (Digital Image Studio) Tel: +61-418-166-870 UTC +10 Hours Gmail, eBay, Skype, Twitter, Facebook, Picasa: distudio -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
