How to make a grey card?

Any suggestions on how to make an accurate grey card?
regards
PeterH

In my search on the internet I came across this article - any thoughts?

Also, if I make a homemade grey card what is the best way to test that it is
correct form my 300D camera?

I presume one way is to get the camera histogram to spike at the midpoint.


"My View" no spam wrote in message
...
Any suggestions on how to make an accurate grey card?
regards
PeterH

this is the article http://www.bythom.com/graycards.htm



"My View" no spam wrote in message
...
In my search on the internet I came across this article - any thoughts?

Also, if I make a homemade grey card what is the best way to test that it
is correct form my 300D camera?

I presume one way is to get the camera histogram to spike at the midpoint.


"My View" no spam wrote in message
...
Any suggestions on how to make an accurate grey card?
regards
PeterH

"My View" no spam wrote:

Any suggestions on how to make an accurate grey card?


I suggest you buy one. In fact, buy three ...

If you buy the Kodak grey card you get three. One is a pocket size
4x5 inch card that's very easy to carry. The other two are 8 x 10:

http://www.bhphotovideo.com/bnh/cont...ughType=search

$17.95 + shipping.

"My View" no spam wrote in message
...
this is the article http://www.bythom.com/graycards.htm



"My View" no spam wrote in message
...
In my search on the internet I came across this article - any thoughts?

Also, if I make a homemade grey card what is the best way to test that it
is correct form my 300D camera?

I presume one way is to get the camera histogram to spike at the
midpoint.


"My View" no spam wrote in message
...
Any suggestions on how to make an accurate grey card?
regards
PeterH

I bought an 18% grey card from my local photography shop and when I
photograph it, my histogram on my 350D shows a nice spike right smack dab
in the middle. Card cost me about $5 I think....

T.W.

There is no such thing as accurate grey card and you don't need a grey card
when you measure the incident light for exposure. Grey card is for reflected
light exposure measurement like the one in your 300D. This meter will see
light as a mixing "glow" of light reflected from the scene. So subject
against dark background and subject against light background will give
different reading due to different "average" reflectance. So a standard
reference in between is created and this is the grey. 12% or 14% or 18%
doesn't matter as long as it is the mid average because usually picture
taken belong to this kind of scene. Therefore if you think that the scene is
too much in light tones (snow scene), compensate a "+" with exposure
compensation function when using auto exposure mode or vice versa. If your
scene match the reference grey after averaging, exposure usually is good. If
you are not sure about it, use a grey card that match the reflectance of the
meter calibration. I say good exposure because there is no perfect exposure
unless you are experience enough to fine tune one. That is why professionals
prefer the incident light meter for exposure reading but use it properly and
correctly or my advice is to use reflected light meter.

"My View" no spam wrote in message
...
Any suggestions on how to make an accurate grey card?
regards
PeterH

My View wrote:
Any suggestions on how to make an accurate grey card?
regards
PeterH


If you have Photoshop or some other graphics editor,create a page in
Grayscale mode and set the RG&B values at 128, 128, 128. Have the
printer print it as a B/W image ( to avoid any color bias from printing
in RGB.) Take that page to a paint store and have them mix up a quart of
flat or satin paint to match that exact color.
Cut up some masonite into 3x5 rectangles and paint them gray.
Give them as presents to your photo buddies. They will appreciate it for
years to come. If you REALLy want to impress them, paint one side gray
and the other side pure white.
I did that and was amazed how appreciative everyone was.
The 3x5 card fits snugly in a shirt pocket so it is always handy.
BTW, The 18% gray card only means that its REFLECTIVITY is 18%.
It generally doet necessarily mean that it has NO color bias.
I have compared commercial gray cards from different manufacturers and
they were not the same hue, but they both gave the same (correct)
reading on the camera's light meter.
Bob Williams

In news:LPkXf.1661$kT4.643@fed1read02,
Bob Williams scribed:
snip

BTW, The 18% gray card only means that its REFLECTIVITY is 18%.
It generally doet necessarily mean that it has NO color bias.
I have compared commercial gray cards from different manufacturers and
they were not the same hue, but they both gave the same (correct)
reading on the camera's light meter.
Bob Williams

God help you if you try and colour balance with it, though. ;-)

--
I have no evidence for stating the above, but this is usenet, so I don't
need any.

Bob Williams wrote:
My View wrote:
Any suggestions on how to make an accurate grey card?
regards
PeterH


If you have Photoshop or some other graphics editor,create a page in
Grayscale mode and set the RG&B values at 128, 128, 128. Have the
printer print it as a B/W image ( to avoid any color bias from
printing in RGB.) Take that page to a paint store and have them mix
up a quart of flat or satin paint to match that exact color.
Cut up some masonite into 3x5 rectangles and paint them gray.
Give them as presents to your photo buddies. They will appreciate it
for years to come. If you REALLy want to impress them, paint one side
gray and the other side pure white.
I did that and was amazed how appreciative everyone was.
The 3x5 card fits snugly in a shirt pocket so it is always handy.
BTW, The 18% gray card only means that its REFLECTIVITY is 18%.
It generally doet necessarily mean that it has NO color bias.
I have compared commercial gray cards from different manufacturers and
they were not the same hue, but they both gave the same (correct)
reading on the camera's light meter.
Bob Williams

All well and good...but also a might fine argument for paying your $17.95 @
B&H for three pre-made Kodak cards!! -What a hassle!

Mark² wrote:
Bob Williams wrote:

My View wrote:

Any suggestions on how to make an accurate grey card?
regards
PeterH



If you have Photoshop or some other graphics editor,create a page in
Grayscale mode and set the RG&B values at 128, 128, 128. Have the
printer print it as a B/W image ( to avoid any color bias from
printing in RGB.) Take that page to a paint store and have them mix
up a quart of flat or satin paint to match that exact color.
Cut up some masonite into 3x5 rectangles and paint them gray.
Give them as presents to your photo buddies. They will appreciate it
for years to come. If you REALLy want to impress them, paint one side
gray and the other side pure white.
I did that and was amazed how appreciative everyone was.
The 3x5 card fits snugly in a shirt pocket so it is always handy.
BTW, The 18% gray card only means that its REFLECTIVITY is 18%.
It generally doet necessarily mean that it has NO color bias.
I have compared commercial gray cards from different manufacturers and
they were not the same hue, but they both gave the same (correct)
reading on the camera's light meter.
Bob Williams


All well and good...but also a might fine argument for paying your $17.95 @
B&H for three pre-made Kodak cards!! -What a hassle!

It's a hassle if you don't like to experiment.
But it is FUN if you like to try new ways to custom make stuff.
BTW if you get dirt or grease on a Kodak gray card ( which is paper
based), you cannot easily clean it without seriously altering the
reflectivity and hue. That is probably why they come in sets of three.
Bob