View Full Version : The purple cast
This was shot today at the Downtown Greek deli in Portland. The 2 purple shirts you see are actually black which is the uniform color.
Wow! The QC of the RD-1 wasn't that bad after all...
enochRoot
11-09-2006, 19:12
wow...i think the word "cast" is an understatement!
Jorge, what am I seeing above the tall guy's head?
Jim N.
That is another flaw in the M8's sensor.
It occasionally shows a toy octopus on people's heads.
wongyboi
11-09-2006, 19:24
Wait wait wait....
Okay I understand the whole purple cast issue witht eh Leica M8, what I would like to know is...why that man has an octopus on his head!
EDIT: Darnit, JohnM ^ beat me to it. And OldNick
sevres_babylone
11-09-2006, 19:26
Wow! The QC of the RD-1 wasn't that bad after all...
Let's not get carried away...
And by the way, what colour was the octopus.
Dumb question Sevres, everybody knows octopi can change their colour to their immediate surroundings.....
the octo is purple and not black. so the purple casting only applies to the shirts. It is the restauraunts mascot.
eeeewwwwww...... you made me "ink" myself. :)
So black looks purple, and purple looks purple? That's just scary.
Gabriel M.A.
11-09-2006, 19:49
the octo is purple and not black. so the purple casting only applies to the shirts. It is the restauraunts mascot.
So "purple cast" is not an accurate way to describe it, then? The picture is not all purple.
The purple is not a "flaw" but a feature. A very unwanted feature.
Just like the "blue cast" on white clothing when shooting without a UV filter on film. The problem is, Leica didn't add "black fabric" to their list of brick wall shot tests. Whoever their consultant(s) was(ere) helping them out with this project, they should fire him (or her. Oh, who am I kidding; him)
the octo is purple and not black. so the purple casting only applies to the shirts. It is the restauraunts mascot.
That's why this bug is so crippling. Do you color correct the octupussy or the shirt? What about that spatula on the counter? .... :bang: :bang:
Let's not get carried away...
Well, if you found defects in your R-D 1 during the warranty period, Epson generally said, "Oh, you too, huh? Okay, send it back and we'll send you another one."
Meanwhile, when you find your Leica M8 occasionally causes purple octopi to appear on your subjects' heads, Leica says that this occurs in only a small minority of cases, and is actually an indication of the high quality they achieve by omitting the purple-octopus-blocking filter from their sensor, and the effect actually might be quite useful for creative photography of purple octopi, but if it still bothers you then sometime in the future they will release a fix which will require you to update your firmware and pay for 6-bit coding of all your Leica lenses and install a special purple-octopus-blocking filter on each lens...
If you look at the reflection of the shirts in the chrome trim on the top of the counter - it is also purplish. Similarly with the hair of the fellow on the other side of the counter in the OOF zone.
As to the shadows in the folds of the woman's shirt - they seem "off" too - but that could just be that digis don't do grey tones very well....
Of course this is all affected by the fact that it is a post of a jpeg and is being viewed on my screen which is not "color corrected"....
Of course this is all affected by the fact that it is a post of a jpeg and is being viewed on my screen which is not "color corrected"....
Color corrected screen is overrated. If you're not printing the image, you dont need to color correct your display. You know the purple shadow is "off" because relative to the grey counter, it IS purple..
Good point ywenz, Which do you color correct if you don't remember the colors? I gues you need to hand in the prints and wait for the client to say My dress was blck not purple.
Diggin99
11-09-2006, 20:33
All I can say is.....ok...I am at a loss for words.......
Nancy
at least the white balance looks good. otherwise...I'm with Nancy: speechless.
:)
Jorge were you on AWB or manual set? Are colors of everything else in the photo relatively accurate?
This was shot today at the Downtown Greek deli in Portland. The 2 purple shirts you see are actually black which is the uniform color.
OK, so I fixed it, turn down all the knobs on your monitor, and the shirts do go black :p
This was shot today at the Downtown Greek deli in Portland. The 2 purple shirts you see are actually black which is the uniform color.
willie_901
11-09-2006, 21:09
Easily rectified with an hour or so of skilled Photoshopping. :rolleyes:
Actually, a nice, but sad, example. Thanks for showing it.
auto wb. everything looks good except for the purple people eaters.
NIKON KIU
11-09-2006, 21:21
This was shot today at the Downtown Greek deli in Portland. The 2 purple shirts you see are actually black which is the uniform color.
Are you being serious??? The waiters ears look purple!!!!
Major flaw:(
Kiu
Jorge, what color was the cook's hat? It looks black. Seems odd that certain blacks would look purple.
Matthew Runkel
11-09-2006, 22:03
Only "some synthetic textiles" are rendered as purple. If everything black were affected the same way, it would be a completely different issue with a much easier solution.
http://www.leica-camera-user.com/digital-forum/8937-official-leica-statements.html
sevres_babylone
11-09-2006, 22:42
Why sweat it. Real photographers shoot black and white.:) :rolleyes:
Easily rectified with an hour or so of skilled Photoshopping. :rolleyes:
Actually, a nice, but sad, example. Thanks for showing it.
An hour per frame. So if you shot a wedding and had to produce an album you would have maybe 200 photos to edit from where the groom's tux needed correction. So for one wedding you'd have a month's (assuming 50 hours a week) work in photoshop that couldn't be batch processed. So if you bought an M8 you could shoot one wedding a month. That doesn't sound so easy.....:bang:
buy yourself a nice MP with a scanner and you''l have a full frame 40 Mp "digi"!. And the money you save buy a canon G7 or something like that.
Ronald M
11-10-2006, 00:47
There is an easy fix. Just use photoshop to select all the purple /magenta objects, and do localised color correction or desaturate and turn to greyscale. Seems simple enough to me. Portra 160 never does this so I`ll stick to it.
Why we don`t have do do this with Canon/Nikons/DMR I do not understand.
Ronald M
11-10-2006, 01:03
This is what $5000 should have bought you.
5 min in PSE 2 . 2 more would have got it perfect.
I`m still staying with Portra
Matthew Runkel
11-10-2006, 01:26
There is an easy fix. Just use photoshop to select all the purple /magenta objects, and do localised color correction or desaturate and turn to greyscale. Seems simple enough to me.
Also, each time you take a photo, make a note of any objects in the shot that really are purple or magenta. Then, refer to your notes when implementing the "easy fix."
Alternatively, simply tape a consumer digicam to your M8 and make a record shot with it each time. Refer to the record shots when implementing the "easy fix."
Hi Ronald,
the octopus should be purple.
I think the problem with this is that it can be confusing which purples were originally purple and which of them were black and have to be corrected. So the often-quoted wedding photos might be difficult to fix in Photoshop if the groom happens to wear a purple tie. Or if ten guests arrived in purple desses and another ten dressed in black, and of the ones dressed in black five wear synthetic and another five natural cloth. Of course this is a bit of a borderline case, but the main problem why people are freaking out is that the resulting behaviour appears somewhat erratic.
Apart from the usual problem with overhyped products: if your expectations are X, and the product delivers only X-1, then your disappointment is 1, but if your expectations are 10X, then your disappointment is 9X+1, which is nine times more than the product delivers. So in hyping a product you almost guarantee you're going to be disappointed big time.
Philipp
This is what $5000 should have bought you.
5 min in PSE 2 . 2 more would have got it perfect.
I`m still staying with Portra
I still see purple subjects flowing around are these real purple subject or errors ? (we'll never know)
AShearer
11-10-2006, 04:11
Okay: Here is my first post of a shot. The shirt I am wearing is navy blue and is cotton, not synthetic.
WB is set to tungsten.
Not a happy camper.
"Leica: Making you see the world through rose-coloured glasses." :(
mr roberts
11-10-2006, 09:28
http://www.leica-camera-user.com/digital-forum/9064-m8-back-out-box-possible-solution.html
...as it suggests that a global adjustment in PS is possible (for proofing) and could be run as an action. Not ideal in the end, but a nice workaround to have while they work out the issues.
Easily rectified with an hour or so of skilled Photoshopping. :rolleyes:
Actually, a nice, but sad, example. Thanks for showing it.
About 20 seconds correcting in Nikon Capture NX....
This is what $5000 should have bought you.
5 min in PSE 2 . 2 more would have got it perfect.
I`m still staying with Portra
That octopus has purple fringing...:D
Really.. the only purple cast any of us should be seeing if the sensor could get it right is this purple cast:
http://www.compsoc.man.ac.uk/~heth/helmet/cast.jpg
:D
Dave
However, just to make things simpler, black sometimes looks black ...
That was a BLACK elephant?
http://pbskids.kids.us/images/sub-square-barney.gif
Gabriel M.A.
11-10-2006, 11:05
I think we can agree that this is the Prince (or the Artist Formerly Known as the Artist Formerly Known as Prince) edition Leica.
If I ever get a black M8 (anybody at Solms listening??), I'm calling it SMF ;)
galavanter
11-13-2006, 04:44
Prince ain' nothin'.;) Dig this:
http://www.youtube.com/watch?v=yWsMxLP6rqc
I think we can agree that this is the Prince (or the Artist Formerly Known as the Artist Formerly Known as Prince) edition Leica.
If I ever get a black M8 (anybody at Solms listening??), I'm calling it SMF ;)
Only "some synthetic textiles" are rendered as purple. If everything black were affected the same way, it would be a completely different issue with a much easier solution.
http://www.leica-camera-user.com/digital-forum/8937-official-leica-statements.html
A $5000 black polyester detector?
Is her little black designer dress REALY silk? Only an M8 owner knows for sure!
MarkEDavison
11-16-2006, 20:21
It would be a mistake to think that infrared contamination only effects the Leica M8, and that it only appears in black synthetic fabrics.
See
http://gallery.leica-users.org/v/MarkEDavison/M8infrared/
for shots showing the nature and amount of infrared contamination in 4 different cameras: Nikon D200, Leica M8, Epson R-D1 and Nikon D2h.
The scene was lit with ordinary incandescent, and the cameras were set on fixed white balance: the R-D1 on incandescent and the rest on 2800 K.
There are three shots for each camera: with no filter, with a tiffen hot mirror IR blocking filter, and with a Hoya R72 IR transmit filter. The exposure for all three shots is the same, so the shot through the Hoya R72 gives you an idea of the relative IR contamination of the 4 cameras. You can also easily see how objects which reflect a lot of IR become darker when shot through the IR blocking filter, just as you would expect.
The colors in the Nikon D200 shots are a very very close match to my impression of the true colors in the scene.
There is a mix of synthetic and natural materials in the scene. Note in particular the maroon pile blanket, the black pile jacket at the bottom, the green blanket near the top, the black anodized aluminum Leica lens barrel, and the black neoprene game case. Note carefully how the IR pollution shifts the green pile blanket towards grey, shifts the color of the maroon blanket, and turns the black pile jacket, the anodized aluminum lens barrel and the neoprene case all purple.
For the Leica M8 I have included an extra shot applying the software profile method suggested on leica-user-camer.com. Note that it improves the appearance of the black objects, but not the others with high IR reflectance.
It is true that the Leica M8 has more IR pollution than the R-d1 and the D2h, but it is a question of degree. For all three of these cameras I would suggest the use of an IR blocking filter to give the truest colors, especially when shooting under incandescent light. The Tiffen filter used here is not strong enough to restore the original colors completely. I will be experimenting with a different filter soon and will report on the results.
Mark Davison
I agree with you that it's a matter of degree, but there are other variables, even by setting the 3 white balances on 2800 K, they each have their own version of hot filter and white balance interaction which would have altered the colors yet again differently.
I think the reason why the dark synthetics are mentioned first is because before any of these camera's were even made, it was well known that dark synthetics reflected IR light differently than cottons.
I have a book on IR photography where the author primarily uses IR for wedding photography and mentions that he has to post process the colors when the groom and bridegrooms line up, since the ones wearing synthetic tuxes or tuxes with synthetic trim come out differently from those wearing all natural fabric tuxes.
My critera for what would be acceptable is if there is some way you can tweak those non-M8's WB or other settings to render black synthetics black without a filter in front of the lens, if you can great, if you can't, then it's no better than the M8 issue.
My *ist doesn't do auto WB well, and even manual WB settings are often off, but there is always a manual or alternate setting that will get the colors right. So the *ist works for me, but it is always a caveot I warn others about. Incidentally, the *ist doesn't completely block IR relative to some other DSLRs.
It would be a mistake to think that infrared contamination only effects the Leica M8, and that it only appears in black synthetic fabrics.
See
http://gallery.leica-users.org/v/MarkEDavison/M8infrared/
for shots showing the nature and amount of infrared contamination in 4 different cameras: Nikon D200, Leica M8, Epson R-D1 and Nikon D2h.
The scene was lit with ordinary incandescent, and the cameras were set on fixed white balance: the R-D1 on incandescent and the rest on 2800 K.
There are three shots for each camera: with no filter, with a tiffen hot mirror IR blocking filter, and with a Hoya R72 IR transmit filter. The exposure for all three shots is the same, so the shot through the Hoya R72 gives you an idea of the relative IR contamination of the 4 cameras. You can also easily see how objects which reflect a lot of IR become darker when shot through the IR blocking filter, just as you would expect.
The colors in the Nikon D200 shots are a very very close match to my impression of the true colors in the scene.
There is a mix of synthetic and natural materials in the scene. Note in particular the maroon pile blanket, the black pile jacket at the bottom, the green blanket near the top, the black anodized aluminum Leica lens barrel, and the black neoprene game case. Note carefully how the IR pollution shifts the green pile blanket towards grey, shifts the color of the maroon blanket, and turns the black pile jacket, the anodized aluminum lens barrel and the neoprene case all purple.
For the Leica M8 I have included an extra shot applying the software profile method suggested on leica-user-camer.com. Note that it improves the appearance of the black objects, but not the others with high IR reflectance.
It is true that the Leica M8 has more IR pollution than the R-d1 and the D2h, but it is a question of degree. For all three of these cameras I would suggest the use of an IR blocking filter to give the truest colors, especially when shooting under incandescent light. The Tiffen filter used here is not strong enough to restore the original colors completely. I will be experimenting with a different filter soon and will report on the results.
Mark Davison
Mark,
I have a few of the Heliopan UV/Digital/Analog filters which are apparntly IR cut filters. I will receive them today and experiment with them. Have you had a chance to try out the Heliopan?
madmaxmedia
11-17-2006, 14:35
In addition, the guy's head has purple highlights. Either that or it's the purple strap for the purple octopus, which oddly is not purple (except for the weird purple fringes.) And you can still see purple in the reflection on the counter. Either way, this corrected version clearly looks manipulated.
I think test shots of swatches of cloth can probably be easily fixed with this sort of manipulation. But then throw in real-world photos like this, with reflections, shadows, etc. and a variety of colors the photographyer won't remember later at his computer, and well...the IR filter is starting to look good compared to this.
One can always argue that most shots won't have people with purple hats, etc...But who wants to have to deal with this on a piece of equipment like a Leica M8?
the octopus should be purple.
I think the problem with this is that it can be confusing which purples were originally purple and which of them were black and have to be corrected. So the often-quoted wedding photos might be difficult to fix in Photoshop if the groom happens to wear a purple tie. Or if ten guests arrived in purple desses and another ten dressed in black, and of the ones dressed in black five wear synthetic and another five natural cloth. Of course this is a bit of a borderline case, but the main problem why people are freaking out is that the resulting behaviour appears somewhat erratic.
ChrisPlatt
11-17-2006, 15:51
I guess Leica hasn't "fixed" the M8 properly. ;)
Chris
RogerDunham
11-19-2006, 12:21
Mark,
I have a few of the Heliopan UV/Digital/Analog filters which are apparntly IR cut filters. I will receive them today and experiment with them. Have you had a chance to try out the Heliopan? I bought the 55mm version because I thought it might work and its a difficult size to get in the B+w version but I still don t have my M8 yet. So I am interested . I read another thread where the tests showed that the heliopan filtered only part of the IR out when comapred to the B+w 486....but this might be fine for normal lighting and preferrable in some instances.
See what happens to your face, when you are photographed with a M8?
http://www.rangefinderforum.com/photopost/data/6346/black.jpg
See what happens to your face, when you are photographed with a M8?
http://www.rangefinderforum.com/photopost/data/6346/black.jpg
I find interesting the guy in the black suit on the right :p
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