Finally, a D300 Near UniWB JPEG

Started Apr 3, 2008 | Discussions
Raul Veteran Member • Posts: 8,439
Thank you Golly

That is the one I use; just saw the name and thought it was a different one (blame it on my youth)

kindest regards

r

gollywop wrote:

Raul:
Open Picture Control Utility and start with a Neutral (predefined)
case. Drop the Sharpening to 0 -- keep everything else at 0 --, and
click "Use Custom Curve." Now pull the center of the curve down with
a single point to a position as close as you can get it to Input 128,
Output 56. Now click "New," and name your custom curve. Finally,
export it to your CF card. It will be put in a folder named NIKON,
subfolder CUSTOMPC, file PICCONxx.NCP. Then follow the instructions
in the manual for loading a custom curve.

But beware, the resulting tone curve will produce an LCD image that
is very, very dark, and perhaps, as a result, pretty useless. Still,
one can use it to take a test shot just to see what the histograms
look like under your shooting conditions.

 Raul's gear list:Raul's gear list
Nikon Df Nikon D5 Nikon D850
GaborSch Veteran Member • Posts: 7,203
I still don't see,

why the Expodisk shot sould not be useful with UniWB. This reqquires manually picking the WB from the Expodisk shot, but that's not a problem, it is?

gollywop
gollywop Veteran Member • Posts: 8,284
Re: I still don't see,

Where are you going to pick it from, Gabor? It is not used to actually take a picture; it is used to establish a manual preset WB in d-0 from the light of the scene you are going to shoot. Then you shoot using that WB. There is no gray card or gray area involved.

See, for example,

http://www.kenrockwell.com/tech/expodisc.htm

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gollywop

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GaborSch Veteran Member • Posts: 7,203
That's right, normally,

but if you do make a shot with the Expodisc on, then you are supposed to get a grey image, and that can be used for picking WB.

gollywop
gollywop Veteran Member • Posts: 8,284
Re: That's right, normally,

So, basically, you are saying that, if you take a shot with the Expodisc on, the resulting image, which, of course, would not be homogenous in intensity or luminence, would nevertheless contain nothing but things that could be interpreted as various shades of gray. If this is the case, then I agree with you. But, is this the case?

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gollywop

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gollywop
gollywop Veteran Member • Posts: 8,284
Re: Thank you Golly

Yeah, I've suffered from the same problem for nearly seven decades.

take care

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gollywop

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GaborSch Veteran Member • Posts: 7,203
From the official explanation:

Put your camera in manual focus mode (just for the test shot), and put the ExpoDisc over the front lens. Point the camera at the dominant light source and take a picture. So, if you're in a room where the dominant source is an open window, point the camera at the window. If the dominant light source is overhead lighting, then point the camera in that direction.

Once you take the picture, it will record a gray image that you can review on your LCD

The Expodisc is basically a white object, the difference between using this and the usual white/grey object is, that you don't photograph the reflected but the transmitted light. Therefor you direct the camera towards the light source, not towards your scenery.

gollywop
gollywop Veteran Member • Posts: 8,284
Re: From the official explanation:

Then I'd say you're correct, and there is no need to switch. One of these days I think I'm going to have to invest in one of these things -- if only to really see how it works. I use the WhiBal gray card, and it works well, but I hear good things about the Expodisc.

Thanks again,

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gollywop

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Iliah Borg Forum Pro • Posts: 25,844
Re: Why so less interchange of ideas?

lovEU wrote:

Why is it such difficult to get all parties to one place? No real
conference organized by some of the big players like IEC, ICC or so?

I think digital imaging is very synthetic (as in synthesis of many very different fields of science and engineering) and complicated; it is also a field of fierce competition as a lot of trade secrets involved along the path starting from capturing light and to the final image.

What I basically want is that pro and semi-pro lines of cameras continue to exist with the primary goal of image-taking, not image-processing (unless we are talking Polaroids here). It means we want to close the gap between the terms used by, say, hand-held meters -- and terms used to present the result on the back of the camera. Seeing that histogram is to the left of the right wall by 4mm, how do we know what exposure compensation to use? Why the question of the zone where the eye can recognize maximum amount of details seems to be never asked in conjunction to metering standards? Where this zone of maximum perceived details is positioned on the histogram? How to isolate the subject and see the histogram of the subject only? Why not to indicate the focusing distance and approximate DoF? Those are just some examples of questions that should be answered by the joint effort of ISO, camera making companies, and photographers.

Colour profiling and other raw processing tasks will be easier if the spectral characteristics of the sensors are known. At this stage we can only dream of that. Current camera profiling software, including ProfileMaker, are of very limited use for general profiling. They should at least allow accurate manipulations of 4-channel linear data at the input and create floating point transforms to perceptually uniform Lab space, like UpLab which allow saturation moves without introducing colour shifts. They should not mess with tone curves, too. They should allow easy creation of multi-shot bracketed sources of known targets to better define colour gamuts. They should allow easy creation of spot-colour targets; those are the only way to profile for mineral pigments found in oil paintings and organics in water-colours,... Those issues are in the hands of ICC, software designers, and photographers.

And of course we have certain questions when it comes to raw conversion. For example: what one is supposed to do if he exposed to the right, but the subject is 2-3 stops underexposed as a result?

I trust we are up to some slow progress in the above; hopefully, step by step improvements instead of gimmicks and "more Photoshop in the camera". Separate committees/sessions/sections with clear agendas are most welcome.

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no text

lovEU Veteran Member • Posts: 3,135
Re: Why so less interchange of ideas?

Iliah, I found your answer to be very valuable. And as usual it made me thinking for some time... After trying to summarize your input I thought it could be worth an own thread:
http://forums.dpreview.com/forums/read.asp?forum=1021&message=27750674

In short, my suggestion is to involve journalists and editors of maagazines to hopefully get a little more motion into the process of improving all those items.
--
regards, eric

PixelDave Regular Member • Posts: 363
Should a custom curve be used in combination with this?

In addition to using this WB setting, is there a custom curve that should also be used?

gollywop
gollywop Veteran Member • Posts: 8,284
Yes:

PixelDave wrote:

In addition to using this WB setting, is there a custom curve that
should also be used?

It is best to use a flat tone curve and all other settings at zero.

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gollywop

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PixelDave Regular Member • Posts: 363
Re: Yes:

Excuse my ignorance, but how does one create this curve?

gollywop wrote:

PixelDave wrote:

In addition to using this WB setting, is there a custom curve that
should also be used?

It is best to use a flat tone curve and all other settings at zero.

gollywop
gollywop Veteran Member • Posts: 8,284
Re: Yes:

PixelDave wrote:
Excuse my ignorance, but how does one create this curve?

gollywop wrote:

PixelDave wrote:

In addition to using this WB setting, is there a custom curve that
should also be used?

It is best to use a flat tone curve and all other settings at zero.

You do it using the Picture Control Utility that comes with Capture NX (and other Nikon software products). Open the Picture Control Utility, select Neutral, click "Use Custom Curve," which will default as flat, click New, Name your curve, put a Nikon-formated CF in your CF card reader, Click Export to put the curve on your card, put the card in the camera, and Load the custom curve to the camera following the instructions on p160 of the Manual.

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gollywop

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PixelDave Regular Member • Posts: 363
Applying white balance afterwards

Sounds easy enough and thank you for providing all the detailed information.

Once the file is imported into ACR or NX and WB is adjusted, can this cause the Red or Blue channels to clip using this method? I guess what will happen once proper WB is applied?

Also, how do you usually determine your WB in order to get accurate or pleasing color?

Thanks again!

Dave

gollywop wrote:

PixelDave wrote:
Excuse my ignorance, but how does one create this curve?

gollywop wrote:

PixelDave wrote:

In addition to using this WB setting, is there a custom curve that
should also be used?

It is best to use a flat tone curve and all other settings at zero.

You do it using the Picture Control Utility that comes with Capture
NX (and other Nikon software products). Open the Picture Control
Utility, select Neutral, click "Use Custom Curve," which will default
as flat, click New, Name your curve, put a Nikon-formated CF in your
CF card reader, Click Export to put the curve on your card, put the
card in the camera, and Load the custom curve to the camera following
the instructions on p160 of the Manual.

colourperfect Contributing Member • Posts: 636
Re: Applying white balance afterwards

Hi,

Is there a web site anywhere that takes you through the process of loading the uniwb file and then making the correct settings in one go. I think it needs one of the experts who's able to explain the process ....

Perhaps I am a bit slow but i am struggling to follow the process

It would then be useful to understand how you create the correct WB in Lightroom.

TIA

gollywop
gollywop Veteran Member • Posts: 8,284
Re: Applying white balance afterwards

PixelDave wrote:

Sounds easy enough and thank you for providing all the detailed
information.

Once the file is imported into ACR or NX and WB is adjusted, can this
cause the Red or Blue channels to clip using this method? I guess
what will happen once proper WB is applied?

Yes, this can happen at the default ACR or NX settings, but, of course, no information has actually been lost. At that point you simply use Recovery or Exposure to bring things back into line and whatever other controls you need to make a good print of it.

Remember also that the ACR zero Exposure setting is actually +0.5EV -- for some reason, ACR applies a "BaselineExposure" setting to all cameras, and the D300's is +0.5. So, if you can remove all evidence of "clipping" with a reduction of Exposure by 0.5EV, you really had no clipping in the first place.

Also, how do you usually determine your WB in order to get accurate
or pleasing color?

Dave, I use the WhiBal gray card, either including it in the shot (in a spot that is either very small and inconsequential or able easily to be removed with the clone tool) or taking a separate shot of the card in the same or similar lighting. I find the WhiBal works extremely well.

Thanks again!

You're welcome.

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gollywop

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PixelDave Regular Member • Posts: 363
Won't that cause noise?

If you have to shift your exposure far enough so that your channels aren't clipping after setting the correct WB won't this cause additional noise in your exposures?

Please confirm.

gollywop wrote:

PixelDave wrote:

Sounds easy enough and thank you for providing all the detailed
information.

Once the file is imported into ACR or NX and WB is adjusted, can this
cause the Red or Blue channels to clip using this method? I guess
what will happen once proper WB is applied?

Yes, this can happen at the default ACR or NX settings, but, of
course, no information has actually been lost. At that point you
simply use Recovery or Exposure to bring things back into line and
whatever other controls you need to make a good print of it.

Remember also that the ACR zero Exposure setting is actually +0.5EV
-- for some reason, ACR applies a "BaselineExposure" setting to all
cameras, and the D300's is +0.5. So, if you can remove all evidence
of "clipping" with a reduction of Exposure by 0.5EV, you really had
no clipping in the first place.

Also, how do you usually determine your WB in order to get accurate
or pleasing color?

Dave, I use the WhiBal gray card, either including it in the shot (in
a spot that is either very small and inconsequential or able easily
to be removed with the clone tool) or taking a separate shot of the
card in the same or similar lighting. I find the WhiBal works
extremely well.

Thanks again!

You're welcome.

gollywop
gollywop Veteran Member • Posts: 8,284
No.

At most you will have to make very minor changes, and, if the original exposure was correct, you are only doing minor changes to correct and unclipped data.

You are too hung up on all this. Give it a try and answer your own qualms.

best wishes,

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gollywop

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PixelDave Regular Member • Posts: 363
Will do...

But I am just trying to understand what I can possibly gain by doing this?

Seems like it would be fairly difficult to maintain proper WB during the golden hour when the light is rapidly changing.

Realistically, how much more DR do you gain by going this route? Half a stop perhaps?

I suppose it is unfortunate that Nikon does not offer a true RAW histogram with correct WB as an option. I am sure they could deliver something like this through a firmware update.

gollywop wrote:

At most you will have to make very minor changes, and, if the
original exposure was correct, you are only doing minor changes to
correct and unclipped data.

You are too hung up on all this. Give it a try and answer your own
qualms.

best wishes,

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