Need an exposure crutch?

PhotosGuy wrote in post #7106718
Yes, in this case. Look at your last image. You had different light at the camera than you had at the paper. Remember in the 1st post I said in bold type, "in the light that’s hitting the subject"?

Bummer - That was the silliest mistake ..

PhotosGuy wrote in post #7106718
You took the loooong road to get there, but that sounds about right.

Nevertheless, this was very interesting. Thanks very much for the patience in answering the repeated questions

No sweat. Your turn now to pass it on to someone else.

After about a total of 3 hours of reading , I can't find the chart I was looking for .
I made one from information I found on this site [I think]
I lost it [It may show up I hope]
any way it was
ISO 100 - lens X mm = 1/X shutter - f stop [I think it was f4]
These are probably wrong I checked here and at borders on Sunday could nor find .
ISO -- -- Shutter speed -- -- f stop
no -- -- -- 2 -- -- -- buy a meter time
no -- -- -- 4 -- -- -- f 1
no -- -- -- 8 -- -- -- f 1.4
no -- -- -- 15 -- -- -- f 2.8
no -- -- -- 30 -- -- -- f 4
no -- -- -- 60 -- -- -- f 8
100 -- -- -- 125 -- -- -- f 16
200 -- -- -- 250 -- -- -- f 22
400 -- -- -- 500 -- -- -- f 32
800 -- -- -- 1000 -- -- -- buy a new lens
1600 -- -- -- 2000 -- -- -- buy a new lens
3200 -- -- -- 4000 -- -- -- buy a new lens
I have an XTI - no meter - I put in auto push shutter 1/2 look a reading and go from there .
I would use straight line at 100 to begin , then if camera said
400 -- 1/30 -- f 4 since 400 is 2 below 100 I would / could do 125 at f 1.4
400 -- 1/60 -- f 2.8
Anyway I need the number of f stop and shutter speed to make another chart .
I know this changes with the mm of lens , so 100 ISO and 1/mm of lens = ? f stop ?
Does this make sense ?

suscribe to this thread

Why?
Gray Card…White Paper. What’s best?

scottbergerphoto wrote in post #690355
Using your hand is a great tool unless you look like Casper the Friendly Ghost or have very dark skin. It's close enough to %18 Grey so as not to throw off your range of tones.

What should I do when Photographing Dark Skin People? Me being a dark skin man can i meter in on my hand?

JerelXTI, I believe the palm technique works for any skin colour, If your palm is darker than average you might be maybe a half stop further.

Your hand doesn't tan, & in post #1 you're finding out what the exposure reading of your hand is & how much bias of the needle it needs to get the proper exposure for a flat white.
For a dark skin color, you probably shouldn't want to re-compensate your exposure or you will lighten the skin unnaturally if you still (mistakenly) shoot jpg.
(mistakenly) because advanced users already know how they want to expose their images. This is written to help those who need help.

If you shoot raw, you might increase the exposure up to 1 stop, which will reduce noise when you correct the exposure before you convert RAW to jpg, as is explained in Expose (to the) Right

Once you 'calibrate' your palm, you don't need to change anything shooting RAW. With jpg, you still need to consider just what is important in the subject. I've calibrated mine to slightly blow out some highlights in chrome, give me a good flat white, & still carry detail in black tires. It's a crutch, not a wheelchair, & you need to watch where you put your feet?

I am on the M kick now.

This thread has provided for some good reading and some interesting points/tips.

I just wanted to give a big thanks for this thread. I wish I would have had this information a couple of years ago, but I am sure happy that I have it now. M mode isn't nearly as scary all of the sudden.

Now it's your turn to pass it on!

OK, I know I must be dense here but I just can't make this work for some reason. I wrote down my steps and settings, perhaps someone can show me where I am going wrong:

(1) Take a piece of white paper and lay it on the ground, set the camera to "P" mode and take a picture making sure the paper takes up at least a third of the frame. This gives me an exposure of f/8.0, 1/160, ISO 100.

(2) Change to "M" and put those settings in the camera. I then take pictures of the paper until the histogram shows the peak from the white paper biased to the right side. In my case this gives me an exposure of f/8.0, 1/80, ISO 100. The meter on the camera shows I am exposed one full stop to the plus side.

(3) Remove the white paper and put my hand in the frame. Half press the shutter and look at the meter. The meter shows -2/3 to -1 stop (bounces between the two). This seems strange to me that the meter shows under-exposure by a full stop.

(4) This should give me the "gray-card" reading for my palm which happens to be -1 stop. If I then use my palm to get my exposure, every shot I take gives me the exact opposite of what I want. Every shot is exposed all the way to the left not the right.

Where am I going wrong here?

DaveSt wrote in post #8620917
...

(3) Remove the white paper and put my hand in the frame. Half press the shutter and look at the meter. The meter shows -2/3 to -1 stop (bounces between the two). This seems strange to me that the meter shows under-exposure by a full stop...

Was your hand in the same light as the white paper when you shot it on the ground?

Methodical wrote in post #8621875
Was your hand in the same light as the white paper when you shot it on the ground?

Yes it was. I actually tried the same test a few times, always careful to make sure my hand was in the same light. I always come up with a negative number for some reason. Maybe my hand has special light adsorbing powers ...

DaveSt, your camera should have 3 whole stops of headroom above "middle grey" before you start to see clipping. What you have done is to meter the white paper as though it was a grey card (the camera has no idea whether it is white, grey or black, but it sets an exposure to render the paper as though it was middle grey) and then increase the exposure, rather modestly, to put the paper at +1. That is not enough. If the white paper is only at +1, what sort of things can you think of that would be brighter than sunlit white paper? Apart from light sources or direct reflections of the sun I can't really think of anything that would make use of the further 2 stops you have to spare. Maybe some paint and plastics could be a little brighter, but I doubt by 2 stops. In my opinion you should be placing the paper at +2 stops (at least). That will still give you a whole stop to spare and, if you shoot raw, even more headroom that you should be able to recover, if you clip one or more channels.

Also, I'm not sure about how you are metering in the first place. IMO you should use a metering mode other than Evaluative and you should fill the metered area with the subject. If you use CWA metering then you need to fill the whole frame.

Once you have sorted out a "correct" manual exposure for the paper, then you can meter off your palm and see what the reading is.

An alternative approach is simply to pick a bright sunny day and set an exposure that matches the "Sunny 16 Rule", such as f/16, 100 ISO, 1/100. Then face away from the sun, hold up your palm in front of the camera, making sure not to cast a shadow on your palm with the lens, and then note the meter reading. That should be what you aim for. I recommend spot or partial metering in order to ensure you are only metering your palm and not the surrounding scene.

Lastly, I have white skin and metering my palm at +1 1/3 works well for me. If you have dark skin then (in my limited experience) you may find that something like +2/3 is better for you. It's also worth noting that such an exposure should preserve highlight detail in brilliant white things, such as a sunlit swan's feathers, but if your scene contains nothing very bright/white then you may do well to increase the exposure by 1 stop in order to capture more shadow detail. An example would be a brown or black dog against a background of grass.