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05-20-2012, 11:55 AM   #151
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Vincent,

That's much better. Thank you.

05-20-2012, 12:30 PM   #152
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QuoteOriginally posted by john5100 Quote
If anyone has any pointers, please help

On the first pic; one has to try to reduce the shadow perhaps a bit more; or even move it; by moving the lighting further from the camera; using bounce - or fill. Perhaps a bit of everything.

On the second pic; would have been better wide open on the aperature and/or darkening out everything except the main subject.

But you do have an above average start though; just need some minor refinements
05-20-2012, 10:51 PM   #153
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@Medium FormatPro

Good suggestions. I didn't think about the shadow but I was concerned about the hard black line. I like the blurred idea as well.

Thank you

John
05-28-2012, 10:44 AM   #154
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I've stumbled across this:

Color Rendering Index on Wikipedia:
QuoteQuote:
Film and video high-CRI LED lighting incompatibility
Problems have been encountered attempting to use otherwise high CRI LED lighting on film and video sets. The color spectra of LED lighting primary colors does not match the expected color wavelength bandpasses of film emulsions and digital sensors. As a result, color rendition can be completely unpredictable in optical prints, transfers to digital media from film (DI's), and video camera recordings. This phenomenon with respect to motion picture film has been documented in an LED lighting evaluation series of tests produced by the Academy of Motion Picture Arts and Sciences scientific staff.[30]
That reference leads to this:

Solid State Lighting Project from the Academy of Motion Picture Arts and Sciences
very interesting videos from the symposium.

It appears that solid state lighting ie: LEDs can cause lots of problems in film and video -
even when they may appear to the eye as indistinguishable from normal lighting for the film industry.
this is because of their "discontinuous" spectrum (their words)

There are lots of videos - this is a "summary" of sorts:

Summary

This is a good example

Makeup Case

These are much more "subtle" if you like than the drastic cases for my overwhelming color washes - but shows how using discrete and "discontinuous"/spiky light sources can cause problems with things like flesh tones - even when they may seem by eye indistinguishable from normal lighting.


Last edited by UnknownVT; 05-28-2012 at 11:02 AM.
08-06-2012, 11:44 AM   #155
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It's not just JPG compression - SubSampling can make a significant difference.

This is something I was not really aware of until recently
and looking back at my olde photo editor I "discovered" this - after over 7 years' of almost daily usage

We all know the higher the compression in JPG the more likely the visible image degradation - especially in Red and Magenta - I tried to illustrate this in the earlier post #123 (link) - I'll paste the relevant bits below:

QuoteQuote:
I did an experiment to demonstrate this a bit more objectively and consistently.

Opened a new image filled half with black and the remaining white.
Then typed in the main colors of my photo editor (PhotoImpact 8) in each half and saved it as a PNG which is lossless.


Using my usual JPG compression level PI=70 (11Kb)

we can see degradation in the Magenta -
due to the degradation in Red and Blue.

Even at PI=100 (highest quality) (34Kb) there is degradation in the loss of vividness in the Red and Blue -


PS Elements seems to fare much better -
PSE = 10 (12 is the highest quality) (28Kb)
SO how does subsampling come into play?
I haven't done my research on how it's done, yet (see bottom of post for link to an explanation),
but can show what it does -
look at the PhotoImpact JPG quality 70 image (which shows pretty obvious degradation compared to the lossless PNG.)


Now here the image saved to the SAME JPG quality/compression 70 using PhotoImpact:


The only difference is that I selected NO subsampling when saving the JPG
of course the file size is bigger at 15kb vs. 11kb with subsampling.

BUT I would venture to say this is better than the PhotoImapact quality=10 @ 34kb;
and probably as good as the PS Elements JPG quality=10 at 28kb.

There is also in PhotoImpact a subsampling level of YUV422
(the default is YUV411 the highest subsampling and smallest file size) -
I was pleasantly surprised at how good this one was @ 13kb:


FWIW - I found these that may help explain things:

Optimization of JPEG (JPG) compression settings: images with good quality and small size - Web design tips & tricks

Chroma subsampling - Wikipedia, the free encyclopedia

Last edited by UnknownVT; 08-06-2012 at 02:13 PM.
08-07-2012, 11:57 AM   #156
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I thought I'd go back to my original problem illustration in the opening post #1:
QuoteQuote:
here's an illustration:

this is with my normal post-processing/sharpening and JPG quality level -
it looks soft and even out of focus.
and use the original JPG - resize - 1 level sharpen
and saved with my usual 70 quality in PhotoImpact 8 -
No subSampling (34kb)


default YUV411 subSampling (same setting for the photo in opening post) (23kb)


medium YUV422 subSampling (27kb)


To see better here are bigger versions
(the smaller versions were to compare with previous filesizes)

NO subsampling (57kb)


default YUV411 (highest) subsampling (39kb)


medium YUV422 subsampling (46kb)


For me and for this photo I would have to use No subsampling to have the photo acceptable -

The default YUV411 (high) subsampling makes the photo look blurred and even out of focus.

YUV422 (medium) subsampling looks better - but still not quite acceptable.

Last edited by UnknownVT; 08-07-2012 at 08:12 PM.
08-07-2012, 12:42 PM   #157
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Anyone who's ever worked in film, TV, or on the stage can tell you that lighting for things like that can be very, very tricky. In the old days of TV color green would look gold no matter how they filtered it. On stage and on camera you practically had to plaster yourself with makeup to look halfway decent. Still do on stage. I've never tried it but I've often wondered if using a colored filter might not help a bit sometimes. That's what they used to try for TV.
08-07-2012, 12:55 PM   #158
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QuoteOriginally posted by UnknownVT Quote
I thought I'd go back to my original problem illustration in the opening post #1:
and use the original JPG - resize - 1 level sharpen
and saved with my usual 70 quality in PhotoImpact 8 -
No subSampling (34kb)


default YUV411 subSampling (same setting for the photo in opening post) (23kb)


medium YUV422 subSampling (27kb)


For me for this photo I would have to use No subsampling to have the photo acceptable -

The default YUV411 (high) subsampling makes the photo look blurred and even out of focus.

YUV422 (medium) subsampling looks better - but still not quite acceptable.
This is a classic LED lighting issue, for some reason the guys behind the board seem to love magenta, which has no green at all. a giant PITA
you've given up a big chunk of the info on your sensor when they do this, you can bring it back in the pentax software of all things which will add green back in to the equation when you correct WB, if you control the amount of correction you can still maintain some of the stagelight drama
Personally i hate the damn things, and usually end up shooting in such clubs in b/w, which tends to suit the bands i shoot most anyway (rockabilly/punk etc)

08-07-2012, 02:33 PM   #159
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QuoteOriginally posted by magkelly Quote
Anyone who's ever worked in film, TV, or on the stage can tell you that lighting for things like that can be very, very tricky. In the old days of TV color green would look gold no matter how they filtered it. On stage and on camera you practically had to plaster yourself with makeup to look halfway decent. Still do on stage. I've never tried it but I've often wondered if using a colored filter might not help a bit sometimes. That's what they used to try for TV.
Thanks for the input -
I touched on this in an earlier post (#154)

Yes, LED lighting is a well known problem with broadcast video and film.

From: Color Rendering Index on Wikipedia:
QuoteQuote:
Film and video high-CRI LED lighting incompatibility
Problems have been encountered attempting to use otherwise high CRI LED lighting on film and video sets. The color spectra of LED lighting primary colors does not match the expected color wavelength bandpasses of film emulsions and digital sensors. As a result, color rendition can be completely unpredictable in optical prints, transfers to digital media from film (DI's), and video camera recordings. This phenomenon with respect to motion picture film has been documented in an LED lighting evaluation series of tests produced by the Academy of Motion Picture Arts and Sciences scientific staff.[30]
Using the link at Wikipedia take us to this page - Solid State Lighting Project
very interesting videos from the symposium.

It appears that solid state lighting ie: LEDs can cause lots of problems in film and video -
even when they may appear to the eye as indistinguishable from normal lighting for the film industry.

There are lots of videos - this is a "summary" of sorts:

Summary

This is a good example with flesh tones and makeup -

Makeup Case

Last edited by UnknownVT; 08-07-2012 at 08:27 PM.
08-07-2012, 05:44 PM   #160
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QuoteOriginally posted by eddie1960 Quote
This is a classic LED lighting issue, for some reason the guys behind the board seem to love magenta, which has no green at all. a giant PITA
you've given up a big chunk of the info on your sensor when they do this, you can bring it back in the pentax software of all things which will add green back in to the equation when you correct WB, if you control the amount of correction you can still maintain some of the stagelight drama
Personally i hate the damn things, and usually end up shooting in such clubs in b/w, which tends to suit the bands i shoot most anyway (rockabilly/punk etc)
Thank you so much for your confirmation.

Nice to see you calling it a "classic" problem -
this shows how LED stage lighting and the dreaded magenta have become prevalent.

Of course this was only a trend when I first started this thread in March, 2010.

Actually by eye - like many others (including lighting persons)
magenta is actually flattering and somewhat attractive -
I only started to detest it when I realized that it played havoc with my photographs.

Although it may be true to be able to show how good the lighting was is somewhat dependent on photos -
most of the time it is only a thing of the moment at the venue -
dependent on the lighting person and audience there -
if magenta were so hated (other than by us photographers) -
then there be far less of it -
clearly it is well liked, by more than just the lighting person.....

So since us photographers aren't necessarily the most important aspect at a show -
I just had to learn to suck it up.

Shooting black and white is one way -
but I really wanted to be able to convey the colors I saw,
and the mushy magenta photos was not what I saw -
so it became a challenge.

That's why there is this thread -
I have posted in this thread some ways I have found to mitigate strong magenta lighting.

A kind of summary of my attempts is in Post #125 (link)
and Post #141 (link) has using the method on the photo above to illustrate the JPG subsampling.

Thank you for corroborating the issue -
please let us know if you find ways to mitigate strong mono-color LED lighting.

Last edited by UnknownVT; 08-08-2012 at 11:54 AM.
08-08-2012, 05:06 AM   #161
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QuoteOriginally posted by UnknownVT Quote
Thank you so much for your confirmation.

Nice to see you calling it a "classic" problem -
this shows how LED stage lighting and the dreaded magenta have become prevalent.

Of course this was only a trend when I first started this thread in March, 2010.

Actually by eye - like many others (including lighting persons)
magenta is actually flattering and somewhat attractive -
I only started to detest it when I realized that it played havoc with my photographs.

Although it may be true to be able to show how good the lighting was is somewhat dependent on photos -
most of the time it is only a thing of the moment at the venue -
dependent on the lighting person and audience there -
if magenta were so hated (other than by us photographers) -
the there be far less of it -
clearly it is well liked, by more than just the lighting person.....

So since us photographers aren't necessarily the most important aspect at a show -
I just had to learn to suck it up.

Shooting black and white is one way -
but I really wanted to be able to convey the colors I saw,
and the mushy magenta photos was not what I saw -
so it became a challenge.

That's why there is this thread -
I have posted in this thread some ways I have found to mitigate strong magenta lighting.

A kind of summary of my attempts is in Post #125 (link)
and Post #141 (link) has using the method on the photo above to illustrate the JPG subsampling.

Thank you for corroborating the issue -
please let us know if you find ways to mitigate strong mono-color LED lighting.
I shoot less and less live music lately, and fortunately most place i shoot still use old school lighting, but eventually they to will make a change because they won't be able to get bulbs
If i come up with anything else i'll post though
09-14-2012, 09:46 PM   #162
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Hi Vincent.

Revisiting this most useful thread, and apologies if this has been answered before somewhere...

I would be interested to hear what practical and simple advice one could offer to a LED lighting guy at a venue to make the lighting more 'photographer friendly'.

After a few problematic recent photo sessions at gigs that were exclusively LED illuminated, I'm keen to know if there are any suggestions I could make to the lighting guys at venues to help reduce the post-processing hassle I have to go through with my photos. And to also ultimately improve the quality of the pictures of the artists involved, since sometimes they like to make use of my shots.

I get the feeling that the solution may not be as easy as just asking the lighting team to add more green or white into their LED panels, but hopefully it may be.
09-14-2012, 11:29 PM   #163
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QuoteOriginally posted by rawr Quote
I get the feeling that the solution may not be as easy as just asking the lighting team to add more green or white into their LED panels, but hopefully it may be.
Funny, I was just talking to another photographer tonight about LED lighting at a venue where they've lit with a quite attractive "white", and I shot at the night before.

Unfortunately even though I thought the light was actually very attractive by eye -
my photos did not come out that way -
here's an illustration actually from same venue - the night before.

This is more or less what I saw:


the unretouched/resized photo - EXIF attached -


Having experienced this, tonight I played around with various white balance presets. and found for the stage lighting tonight, the balance was close to either Cloudy or Shade presets viewed on the K-x LCD -
Cloudy sometimes looked too cool, and Shade sometimes looked too warm.

...and the problem was that the WB could vary at different parts of the stage since each PAR or LED array could be set differently - especially if done by eye - as my photo illustrates - because I thought I saw the first photo whereas the K-x captured the second version.

The main problem is that most of the LED arrays/matrices are made up of discrete RGB LEDs

Although this would seem to suit the Bayer RGB matrix of our digital cameras -
this is not actually so. Our Bayer matrix are using RGB filters to "see" or analyze the light -
whereas the discrete red, green and blue LEDs are generating/giving out separate and narrow red, green and blue spectrum which is "discrete" - before anyone argues let's compromise and call it very peaky at red, green and blue - which does not resemble the white of daylight which is a much smoother continuous spectrum -
that's why even when set to "white" LEDs are still difficult to deal with photographically.

See previous Post #48 -
typical "white" spectrum generated by discrete RGB LEDs -


So I have learned to suck it up and deal with it -
so I don't actually ask the lighting person to change anything -
especially if they have avoided the pitfall of strong mono-color and trying to give "white" -
I am already grateful for that small mercy.
It is then really only a white balance problem.

How did I deal with the blue/magenta cast from last night?

I actually selected and open each and every photo (JPG) from last night in PDCU -
and used the gray-point selection on some convenient white spot which removed the cast.

Then after doing the brightness/contrast adjustments I re-added magenta/blue or even red to get it to more or less "as I saw it".

Link to first pic of 9 from last night (navigate forwards from there) -

https://picasaweb.google.com/UnknownVincent/Chapo#slideshow/5788091152013216050

Sorry LED stage lighting is so prevalent these days because of the economy and attraction of being able dial in almost any color - that most venues are switching to them - it would be impossible to educate all lighting persons

.... and how? by eye? -
even then I have shown I can fail miserably myself and I am aware of the photo problem -
eg: I would have quite happily dialed in the same "white" last night -
and yet my photos looked too blue/magenta........

So the only way to check is to take photo of the stage lighting to make sure -
and is it then reasonable to expect the venue to fix and keep that setting -
when they've paid for lights that can do 16.7 million colors?

Sorry to be so bleak -
I find the only thing within my control is myself -
so I learn to deal with things.

Last edited by UnknownVT; 09-15-2012 at 12:10 AM.
09-15-2012, 06:33 AM   #164
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Aha. Thanks for that informative reply.

So the situation basically looks grim. PDCU and even Lightroom 4 have been working OK for me, so I too can learn to deal with things I guess.

However one day I will show some of the local lighting guys on a laptop screen what the problem looks like so that they may 'see' what the issue is, and perhaps we might be able to work something out.

Anyway, this is the sort of thing I've had to deal with lately, and some of my recovery efforts (I shoot RAW+ so have the out-of-camera JPG's around):

JPG out of camera:


Processed DNG:


JPG out of camera:


Processed DNG:
09-15-2012, 08:10 AM   #165
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QuoteOriginally posted by rawr Quote
Aha.
So the situation basically looks grim.
However one day I will show some of the local lighting guys on a laptop screen what the problem looks like so that they may 'see' what the issue is, and perhaps we might be able to work something out.
Anyway, this is the sort of thing I've had to deal with lately, and some of my recovery efforts (I shoot RAW+ so have the out-of-camera JPG's around)
Yikes!!
No, you have a much more severe problem of very strong mono-colored LED lighting -
as in my opening post and the main theme of this thread earlier on.

This kind of lighting you can discuss with the lighting person to give you more "white" and less of the strong mono-colors.

I (still) have to deal constantly with strong mono-colored lighting - since lighting people, especially in popular music venues like them, and I guess so do audiences - hence the popularity and predominance of these LED lights at venues.

If I may point you back at an earlier Post #125
where I gave a sort of summary of how I now deal with strong mono-colored LED lighting -
also Post #141 where I used the same technique on the severe problematic photo from the opening post.

These were all done with JPGs
So your RAW ought to give you better flexibility.

OK since I mentioned (what is now) last night - ie: the following night from the examples I posted

This is dealing with what appears to be "white" light - but lit by discrete RGB LEDs -
which gives more often than not white balance problems.

What it kind of looked like to my eyes -

confession I did warm it up a little, since there are females in the pic......

This what my K-x took (EXIF attached) -

not horrible - but kind of "off" -
BUT there is a "hidden" problem (illustrated by your second uncorrected JPG too)
often the colors are over-saturated since the imbalance fools our meter -
even if one is aware of this and makes exposure compensation/corrections -
the post processing is difficult - and any brightness/contrast adjustments can blow out important parts of the photo - so do the white balance or color corrections first before attempting to adjust brightness etc.

Then off to the (left as we see it) side of the stage:
Original, EXIF attached -

acceptable but not so nice -
WB correction - gave too much green (opposite of magenta) - so deselected the fiddle player's face and added back magenta until the green was minimized -
result -


These were all JPGs and done only in my "free"-with-magazine editor, very olde version - Ulead PhotoImpact 8

Good luck.



Last edited by UnknownVT; 09-17-2012 at 09:52 AM.
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