Gray Card and Photoshop Question

I just bought a gray card for my D-60.

This is how I use it. I shoot in auto white balance the gray card and then use that as a custom white balance photo. And then shoot the photos in that partical lighting

1) Is This Correct ?

I noticed one big thing, when I go to Photoshop the autolevel almost does not change ANYTHING, as if the photos were perfect for the levels but...

2) Isn't gray card used only for metering to get the right iso, shutter and apature?

3) the guy in the photostore told me that for white balance he uses plain white sheet. Is one supposed to use white sheet or the gray card for white balance? (I do like the colors that are coming out now,especially indoors, blues are a lot nicer (sharper would be the term)

Obviously in the film there was no way to use custom white balance since there was no way to introduce cutom photo to the camera, so I guess one would use the gray card only for metering correct ?

thanks for the help

anybody has any answers ?

Mario Jesmanowicz said:

I just bought a gray card for my D-60.
This is how I use it. I shoot in auto white balance the gray card
and then use that as a custom white balance photo. And then shoot
the photos in that partical lighting

1) Is This Correct ?

I noticed one big thing, when I go to Photoshop the autolevel
almost does not change ANYTHING, as if the photos were perfect for
the levels but...

2) Isn't gray card used only for metering to get the right iso,
shutter and apature?

3) the guy in the photostore told me that for white balance he uses
plain white sheet. Is one supposed to use white sheet or the gray
card for white balance? (I do like the colors that are coming out
now,especially indoors, blues are a lot nicer (sharper would be the
term)

Obviously in the film there was no way to use custom white balance
since there was no way to introduce cutom photo to the camera, so I
guess one would use the gray card only for metering correct ?

thanks for the help

Click to expand...

Mario Jesmanowicz said:

I just bought a gray card for my D-60.
This is how I use it. I shoot in auto white balance the gray card
and then use that as a custom white balance photo. And then shoot
the photos in that partical lighting

1) Is This Correct ?

Click to expand...

Yes.

Mario Jesmanowicz said:

I noticed one big thing, when I go to Photoshop the autolevel
almost does not change ANYTHING, as if the photos were perfect for
the levels but...

Click to expand...

I never use Auto Levels, it depend heavily on your image content, if your image contains heaps of one colour Auto Levels will get it wrong.

Mario Jesmanowicz said:

2) Isn't gray card used only for metering to get the right iso,
shutter and apature?

Click to expand...

Sure it can be used to calculate exposure, but also WB.

Mario Jesmanowicz said:

3) the guy in the photostore told me that for white balance he uses
plain white sheet. Is one supposed to use white sheet or the gray
card for white balance?

Click to expand...

You can use either white or grey, as long as it is "neutral" in colour terms. I use the grey card since I know it to be neutral. There are many shades of white and depending on your "plain white sheet" you may well be getting WB wrong.

Mario Jesmanowicz said:

(I do like the colors that are coming out
now,especially indoors, blues are a lot nicer (sharper would be the
term)

Click to expand...

Then stick with what works for you.

Mario Jesmanowicz said:

Obviously in the film there was no way to use custom white balance
since there was no way to introduce cutom photo to the camera, so I
guess one would use the gray card only for metering correct ?

Click to expand...

No... I used to use a grey card with a hand held colour temp meter back in the "olden days".

1) Yes
2) No

Custom white balance has nothing to do with iso, aperture or shutter. An image used as a custom white balance is used in the algorithm inside the camera photo to take the raw image from the sensor and convert the individual pixels into the right colours for the jpg image.

That's why if you shoot in RAW, you can do a custom white balance in post-processing i.e. the algorithm can be done outside the camera. If you shoot in JPG, you can't - since the camera has already done the algorithm.

HTH
Martin

Mario Jesmanowicz said:

...

Click to expand...

thank you very much this helps a lot, especially for the New Years Eve Party. The lighting will be the same in the entire area, so I will just take the custom white balance reading of the hte gray card with 550EX Flash at the beginning and then I will just shoot with the custom white balance for the rest of the evening. That sounds right? corect ?

MartinM said:

Custom white balance has nothing to do with iso, aperture or
shutter. An image used as a custom white balance is used in the
algorithm inside the camera photo to take the raw image from the
sensor and convert the individual pixels into the right colours for
the jpg image.

That's why if you shoot in RAW, you can do a custom white balance
in post-processing i.e. the algorithm can be done outside the
camera. If you shoot in JPG, you can't - since the camera has
already done the algorithm.

HTH
Martin

Mario Jesmanowicz said:

...

Click to expand...

Click to expand...

Mario Jesmanowicz said:

thank you very much this helps a lot, especially for the New Years
Eve Party. The lighting will be the same in the entire area, so I
will just take the custom white balance reading of the hte gray
card with 550EX Flash at the beginning and then I will just shoot
with the custom white balance for the rest of the evening. That
sounds right? corect ?

Click to expand...

As long as your flash is going to be the primary light source, all night.... if you start using ambient light you will need to redo the CWB for that light.

If you are using flash, why not just use the pre-set flash WB in camera, do you not find it accurate enough??

Enjoy the party.... in this part of the world it is already 2003.

According to my reading of the D60 instruction book (p 66) you should use a white card, not a gray card to set the camera's custom white balance.

Mario Jesmanowicz said:

I just bought a gray card for my D-60.
This is how I use it. I shoot in auto white balance the gray card
and then use that as a custom white balance photo. And then shoot
the photos in that partical lighting

1) Is This Correct ?

I noticed one big thing, when I go to Photoshop the autolevel
almost does not change ANYTHING, as if the photos were perfect for
the levels but...

2) Isn't gray card used only for metering to get the right iso,
shutter and apature?

3) the guy in the photostore told me that for white balance he uses
plain white sheet. Is one supposed to use white sheet or the gray
card for white balance? (I do like the colors that are coming out
now,especially indoors, blues are a lot nicer (sharper would be the
term)

Obviously in the film there was no way to use custom white balance
since there was no way to introduce cutom photo to the camera, so I
guess one would use the gray card only for metering correct ?

thanks for the help

Click to expand...

--
Tony Cortizas, Jr.
Mac G4 867; Oly C2020, Canon D60, Epson 780.

Mario Jesmanowicz said:

I just bought a gray card for my D-60.
This is how I use it. I shoot in auto white balance the gray card
and then use that as a custom white balance photo. And then shoot
the photos in that partical lighting

1) Is This Correct ?

Click to expand...

It does not matter what mode you shoot the white balance photo in. You just need to make sure that A) the gray/white card fills the circle in the viewfinder (note - focus does not matter), and that B) you meter/expose the gray/white card for the middle of the range/histogram.

Getting the Gray card to fill the circle in the viewfinder is a big trick since it will often be a lot smaller than the subject. IF you hold it closer to the camera you are then sampling light away from the subject. IF the light is uniform, this is no problem, but if it varys that can be a problem (more on that later with the flash). A trick a lot of people use is to put a whitel diffuser or a while foam cup over the front and take a picture as this will tend to give you and average of the light coming back to the camera.

Mario Jesmanowicz said:

I noticed one big thing, when I go to Photoshop the autolevel
almost does not change ANYTHING, as if the photos were perfect for
the levels but...

Click to expand...

Auto levels is not magical, in fact it can be VERY BAD. The new "AUTO" mode in curves is better as you can set the limits yourself, but it is still not magical. What you are doing with a preset white balance is sampling the light that was there.

Mario Jesmanowicz said:

2) Isn't gray card used only for metering to get the right iso,
shutter and apature?

Click to expand...

Technically yes, but since a gray card is neutral gray, it works well. It also simplifies exposure. If you use a WHITE card you still want the "picture" of the card to come out gray. If the white balance picture comes out near white, you will get a lousy white balance setting (the WB picture needs to be in the middle of the range).

Mario Jesmanowicz said:

3) the guy in the photostore told me that for white balance he uses
plain white sheet. Is one supposed to use white sheet or the gray
card for white balance? (I do like the colors that are coming out
now,especially indoors, blues are a lot nicer (sharper would be the
term)

Click to expand...

Technically the white card, but the gray card works. But don't use just any white looking piece of paper. A lot of "white" paper has some blue in it to make it looke "whiter than white" (vary pail blue looks whiter to the human eye).

A WORD ON USING FLASH with white balance. This depends on how dominant the flash will be relative to the ambient light. If you have a mix, then the WB will constantly be changing if the subject distance varies (as in candid shots), or you change almost ANY settings (shutter, aperture, ISO) on the camera. I'm no expert on this, but if I am going to be shooting candids with the flash, I give up and go for auto WB.

For what it is worth, the D30 manual says the same thing. It simply does not matter whether you use gray or white since the object is to have a "neutral" subject filling the center circle area of the viewfinder. This has been discussed many times before on this forum so you might want to do a search on the topic to get more of the same information already presented here.

Happy shooting!

Tony Cortizas Jr said:

Mario Jesmanowicz said:

I just bought a gray card for my D-60.
This is how I use it. I shoot in auto white balance the gray card
and then use that as a custom white balance photo. And then shoot
the photos in that partical lighting

1) Is This Correct ?

I noticed one big thing, when I go to Photoshop the autolevel
almost does not change ANYTHING, as if the photos were perfect for
the levels but...

2) Isn't gray card used only for metering to get the right iso,
shutter and apature?

3) the guy in the photostore told me that for white balance he uses
plain white sheet. Is one supposed to use white sheet or the gray
card for white balance? (I do like the colors that are coming out
now,especially indoors, blues are a lot nicer (sharper would be the
term)

Obviously in the film there was no way to use custom white balance
since there was no way to introduce cutom photo to the camera, so I
guess one would use the gray card only for metering correct ?

thanks for the help

Click to expand...

--
Tony Cortizas, Jr.
Mac G4 867; Oly C2020, Canon D60, Epson 780.

Click to expand...

--
Pat

With a 550Ex, the manual seems to indicate that we should use the outdoor white balance, instead of the flash... and keep the flash white balance for the studio flashes...

or am I wrong ?

Titus

Russell Stewart said:

Mario Jesmanowicz said:

thank you very much this helps a lot, especially for the New Years
Eve Party. The lighting will be the same in the entire area, so I
will just take the custom white balance reading of the hte gray
card with 550EX Flash at the beginning and then I will just shoot
with the custom white balance for the rest of the evening. That
sounds right? corect ?

Click to expand...

As long as your flash is going to be the primary light source, all
night.... if you start using ambient light you will need to redo
the CWB for that light.

If you are using flash, why not just use the pre-set flash WB in
camera, do you not find it accurate enough??

Enjoy the party.... in this part of the world it is already 2003.

Click to expand...

You could be right, I would suggest trying it and seeing. I did not own a 550, but my 420 (before flogging it to get a Metz) was ok on Flash WB.

Titus said:

or am I wrong ?

Titus

Russell Stewart said:

Mario Jesmanowicz said:

thank you very much this helps a lot, especially for the New Years
Eve Party. The lighting will be the same in the entire area, so I
will just take the custom white balance reading of the hte gray
card with 550EX Flash at the beginning and then I will just shoot
with the custom white balance for the rest of the evening. That
sounds right? corect ?

Click to expand...

As long as your flash is going to be the primary light source, all
night.... if you start using ambient light you will need to redo
the CWB for that light.

If you are using flash, why not just use the pre-set flash WB in
camera, do you not find it accurate enough??

Enjoy the party.... in this part of the world it is already 2003.

Click to expand...

Click to expand...

Canon's Chuck Westfall has recommended using a gray card, for several
reasons:

As noted by others in this thread, many "whites" are not truly neutral.
White paper may have other shades (e.g. blue) to enhance brightness.

Also, CWB depends on an accurate exposure. Clipped highlights may
cause errors, and they're more likely to occur with white than with
18% gray.

Finally, Chuck recommends a non-reflective surface for the gray card,
to avoid erroneous glare.

Gray cards are cheap and handy. I recently purchased one which
came with an additional, 4x6" "bonus" card. The "bonus" travels with
my camera, and I use it all the time - while the "real" card mostly lives
in a drawer.

• Dan

I remember the thread and Chuck Westfall's comments. Chuck's comments were directed predominately at studio setups with studio strobes where the exposure and lighting is relatively fixed and the photog doesn't want to change the camera settings or the strobes to render the white card gray in the resulting exposure. In that case there is a risk that the CWB, using a white card, will result in blown highlights and incorrect CWB. However, If you follow the directions in the D30/60 manual with a true white card (back side of Kodak gray card) you will get more accurate white balance. My own tests with a modeling head ( http://www.digerati-imaging.com/D30_WB_Test.asp ) have shown a white card (the back side of a Kodak gray card) to be more accurate than a grey card but you must expose it so it is rendered gray when used for the CWB image.

I have order a couple of Expo Discs and will eventually test them against the white card. If accurate, the Expo Disc will be much more convenient.

Dan Phillips said:

Canon's Chuck Westfall has recommended using a gray card, for several
reasons:

As noted by others in this thread, many "whites" are not truly
neutral.
White paper may have other shades (e.g. blue) to enhance brightness.

Also, CWB depends on an accurate exposure. Clipped highlights may
cause errors, and they're more likely to occur with white than with
18% gray.

Finally, Chuck recommends a non-reflective surface for the gray card,
to avoid erroneous glare.

Gray cards are cheap and handy. I recently purchased one which
came with an additional, 4x6" "bonus" card. The "bonus" travels with
my camera, and I use it all the time - while the "real" card mostly
lives
in a drawer.

• Dan

Click to expand...

--
Doug Walker
Check my profile for equipment list.

Chuck Westfall (Assistant Director/Technical Information Dept. at Canon USA) addressed grey cards/white cards, and CWB in this thread:
http://www.robgalbraith.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=8&t=000245

-dc

Mario Jesmanowicz said:

I just bought a gray card for my D-60.
This is how I use it. I shoot in auto white balance the gray card
and then use that as a custom white balance photo. And then shoot
the photos in that partical lighting

1) Is This Correct ?

I noticed one big thing, when I go to Photoshop the autolevel
almost does not change ANYTHING, as if the photos were perfect for
the levels but...

2) Isn't gray card used only for metering to get the right iso,
shutter and apature?

3) the guy in the photostore told me that for white balance he uses
plain white sheet. Is one supposed to use white sheet or the gray
card for white balance? (I do like the colors that are coming out
now,especially indoors, blues are a lot nicer (sharper would be the
term)

Obviously in the film there was no way to use custom white balance
since there was no way to introduce cutom photo to the camera, so I
guess one would use the gray card only for metering correct ?

thanks for the help

Click to expand...