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Paul Pagano
03-08-2008, 09:26 PM
Somewhere along the line, I learned that shooting white birds requires you to underexpose the bird by perhaps -7/10 to -1 1/3 EV. Usually I get the details saved but have to artificially lighten the exposure in LR.

I have been reading that I should be shooting at +1 1/3 (or so) EV based on spot metering? Is this correct? Or am I just reading it backwards? Wouldn't this just overexpose the bird more? I am planning on trying this next time I get out to the field, but I was wondering what others do? If I read Art's book right, he also does this.

So, maybe I am confusing opening up and stopping down...but do you dial in - or + for white birds? Seemed to me like the only time to dial in + for birds is when shooting black colored birds. Thanks in advance for your help.

Fabs Forns
03-08-2008, 09:35 PM
Paul, the background has a lot to so with this, unless you are spot metering.

The camera meter is set to make everything 18% gray, so if you spot meter a white bird, the meter will make it gray. You need to add light. Opposite with a black bird, the meter will once again try to make it gray, so you need to subtract light to render black.
If you put a white bird, small in frame, in dark foliage, the meter will average a dark scene and open up, thous overexposing our bird. Take the same white bird in snow, and the meter will close, forcing us to add light to render white.

Hope this helps!

Did you see Artie's article on exposure in the E-zine? Of course, he is referring to evaluative/matrix metering, the approach he uses.

Harry Behret
03-08-2008, 11:22 PM
Arthur's article on exposure in the eZine would be a good read.

Paul Pagano
03-09-2008, 06:19 AM
Found it. Thanks!

Kelly Frame
03-26-2008, 07:12 AM
I have a related question to the above. I have been trying to get a decent picture of a common merganser, which has a very dark green head, but white wings. I'm having a very difficult time getting a proper exposure, as I either end up exposing for the wings (and having the head look black and/or losing the eyes) or I end up exposing for the head (and having the wings blown out).

Any suggestions?

Fabs Forns
03-26-2008, 08:18 AM
There's a thread in Educational Resources, Forum on saving whites. It will explain how to save them if you kept details on the whites when you took the picture. Unless there is VERY soft light, it's extremely difficult to get dark and whites properly exposed as a stratight image, so you can help the situation with some post-processing work:

http://birdphotographers.net/forums/showthread.php?t=834

About exposure in general, Arite has an excellent article in the e-Zine, as mentioned.

About straight whites, there's also a good read here:

http://birdphotographers.net/forums/showthread.php?t=8197

Alfred Forns
03-26-2008, 09:13 AM
Hi Kelly for these type birds the only solution is to have soft light The contrast range between the withe and dark feathers is more than the camera can handle In that case you can go to the save technique which Fabs mentioned

Paul the best way to understand exposure is to try for yourself Once you get predictable results you will have confidence

Do try metering on a white subject Can be a white car Get up close and take a reading Make one exposure at meter reading then open one half, full, one and a half ant then two stops more light Look at the results in the computer Can also place a light subject against a dark bg Then try the same with a light bg Nothing like hand on training.

Gib Robinson
03-26-2008, 09:58 AM
Where is the E-Zine? (Where can I find Artie's article?)

Thanks,

--Gib

Charles Glatzer
03-26-2008, 10:32 AM
Paul,

I assume you are shooting white birds in FL sunlight. If so you need only use sunny f/16 and close down 2/3 to 1 EV for the white highlights. Simply remember the acronym 88 w/ ISO 200 as a basis for exposure equivalent 1/800 @ f/8 when shooting in full sunlight, and close down an additional 1 EV for white subjects 1/800 @ f/11 or 1/1600 @ f/8.

Forget metering in sunlight and just shoot the numbers above. Shoot in manual!!!! If the subject is in the same light the exposure need not be altered regardless of the background tonality, and/or the subject's size and tonality relative to the background.

Note- sunny f/16 rule can increase as much as 2/3 EV when light levels are extreme, such as when shooting close to the equator or at high altitude.

Best,

Chsa

Jack Howdeshell
03-26-2008, 10:45 AM
Where is the E-Zine? (Where can I find Artie's article?)

Thanks,

--Gib

Gib,
Look at the menu bar at the top of each page, just under the main banner. There is a button for the link to eZINE.

Jeff Wignall
03-27-2008, 04:28 PM
Hi Paul and all,

This is my first posting on the BPN Forums, but I write about photography a lot and teach and exposure is one of my favorite topics (probably because it was my personal nemesis for so many years--particularly in the film days when I shot slide film almost exclusively).

Fabs first reply above is absolutely correct: All camera meters (and all hand-held meters) are calibrated to render whatever you meter an "average" or middle gray. If you meter a white cat and shoot at that exposure, you'll get a gray cat. If you shoot a black cat (and the image isn't corrected in processing) you'll get the same gray cat. (Incidentally, all books, including mine, will tell you this is 18% gray, but if you do some research online you'll find out that the 18% figure is a tiny bit inaccurate--though, trust me, 18% is darn close--or "close enough for jazz" as they say.) The trick to getting the best exposure is knowing where your subject lies on the scale of grays that range from pure white to pure black.

A white bird, for example, is probably about a stop-and-a-half (depending on how bright the lighting is) to two stops brighter than middle gray. So in order to render the bird white and keep detail in the white areas, you must ADD some exposure (the exact amount really depends on your camera, your meter, your bird, your lighting--there is no pat answer). In most situations, I automatically use 1 2/3+ of exposure compensation. Checking the histogram is helpful, but don't rely on it completely--some of the bird *will* blow out and that's not necessarily a bad thing. Unlike a lot of photographers and photo writers, I do not hinge my exposure decisions on the histogram; while it's a useful "guide" feature, the simple fact that some tones have dropped off the end of the graph (either the highlight or shadow end) is not inherently "wrong." When it comes to shooting white birds, yes, you do want most of the white areas to have some detail, certainly, but in small pockets of very intense light, I think (personally anyway) it's OK if some detail is lost.

Remember though: no tone is an island. As you increase the exposure to keep the whites white, you also increase the exposure in the shadow areas. That is, the black areas and the dark gray areas are also getting more exposure and so you are lightening them, as well. You can't increase one tonal value and not increase others (or vice versa). You can, of course, manipulate the relationships of tonal values in editing (just as film users, like Ansel Adams, did/do in the darkroom). I strongly suggest learning to use the "curves" tool in Photoshop (or any program) because that is the real key to post-production exposure control.

Anyway, the other thing I would suggest is this: If you're shooting some afternoon and have a cooperative white bird (or a black one) who is sitting still and you have your camera on a tripod, and the light remains constant: shoot a series of bracketed exposures ranging from about two stops underexposed to two stops overexposed and then compare the results--both on your screen and in quick unedited prints. Then look at your EXIF data and make some notes on which exposures worked best. Eventually you'll get to know how your camera/meter handle certain types of subjects and lighting combinations and that is what matters most: your equipment and your workflow, etc.

Finally, remember that exposure is a subjective decision. What looks good to you and what looks good to someone else are two different things. No one wants to see all the detail of a white egret blown away--that's just a mistake, not a decision--but if you choose to infuse the scene with mood by darkening the bird down more than I might, that's your decision. I constantly work to get my students to think in terms of right or wrong only in their techniques, but *not* in their interpretations.

Exposure drove me nuts for years and still does at times--especially when I'm working with a new camera. I bless the day that Photoshop was invented though because it has really changed my life and let me salvage some of the really poor decisions I make in the field!

Jeff Wignall
Author, Exposure Photo Workshop (Wiley; March 2008)

Alfred Forns
03-27-2008, 04:45 PM
Welcome to BPN Jeff !!!! Appreciated your explanation It is thorough and complete.

When teaching I do tell the workshop participants to look and rely on the histogram It is the best tool available for checking exposure. I try to get as close to the right side with data as possible without going over. Agree a couple of blown pixels are not big deal but only a couple . I do no like having areas with no density. There is nothing you can do to recover in PS if there is no information

Regarding the shadows. We don't worry their position on the histogram If I have white in the fifth box of the histogram and the black values are in the third it is fine. You can even try exposing for a black surface and exposing so all info is on the fifth box The image would look awful coming out of the camera but would have the greatest color information. Would reproduce just fine.

One of the most important parts of understanding exposure is the different methods to arrive a the same exposure. There is no right or wrong just different and each should be understood.

Jane Ward
03-27-2008, 06:53 PM
Exposure is my personal nemesis and has been since I started taking nature photos. I'm finally understanding some of the basic things that my very patient friend has been explaining to me over the last several years, I'm finally putting my camera in Manual mode and setting the exposure myself, and I'm getting much better results. I have a long way to go before I will be confident about my exposure decisions, but I really appreciate discussions like this. They help me internalize the reasoning I need to go through when I am in the field. Until I do that I'm afraid I'll continue to struggle under unusual light situations.

Jeff Wignall
03-28-2008, 01:39 AM
Hi Alfred,

Thanks for the welcome. I agree that you don't want too many blown out pixels in your main subject, you are exactly correct. However, one thing that can happen is that, suppose there is a specular reflection in the water next to the white bird (a great egret, for example), your exposure for the bird might be carefully considered and dead-on but you are still going to get spikes at the right end of the histogram from that specular highlight that might make someone think they've blown the exposure. If you meter carefully from the subject and adjust the exposure accordingly (and I tend to use aperture-priority and exposure compensation rather than straight manual exposure) you can still get areas that are off-the-chart on the right side of the histogram and yet the subject is perfectly exposed.

But I agree with you, in terms of the main subject, you can't call back what isn't there in terms of detail!

jeff

Fabs Forns
03-28-2008, 05:01 AM
Big welcome, Jeff, and thanks for taking the time to elaborate on exposure :)

Alfred Forns
03-29-2008, 04:38 PM
Hi Jeff You have a good point regarding specular highlights They need to be recognized and often are not It will lead to an incorrect exposure and sometimes of high magnitude.

Agree there is nothing like understanding exposure thoroughly No substitute !!!!!! I can't stress enough for anyone serious on photography to learn by self help or workshop. Workshops will be the fastest way around.

Leroy Laverman
03-30-2008, 08:57 AM
One other thing to keep in mind when using on camera histograms as an exposure guide is that they are based upon the jpeg preview your camera generates. I'm not sure about all cameras but with my Nikon the other setting like saturation, sharpness, white balance are applied to this image and may impact what the histogram looks like. Areas that are blown in the jpeg may in fact be fine in the raw file.

Paul - for egrets up close I've been using center weighted metering with -1/3 to -2/3 eV compensation. The jpeg shows some blown areas on the brightest parts of the birds but they're fine in the raw file. The harder thing to deal with is the large dynamic range of the scene. Bright white highlights and black beaks. Always a challenge to get both of these with good exposure.

Ed Okie
03-30-2008, 11:25 AM
Another point worth consideration: "Spot Metering" is arguably "the best answer" ...and the best teacher. Reading errors smack you in the face with bluntness when you're wrong... you either learn quickly (sometimes painfully), or else you do the normal thing and revert to "auto" or Evaluative readings. Knowing when to use spot metering, and when to use normal metering methods is the key - experience is the best teacher. Dive in with spot metering, make a few blunders along the learning path. Long term, you'll be ahead of the game, have a far better understanding of exposure, and be a better photographer to boot!

Charles Glatzer
03-31-2008, 11:22 AM
With regard to metering, it really matters not the method used, as a firm understanding of exposure should allow the photographer whatever the meter pattern or method used to render the subject as desired. No one method is best for all scenarios, a competent photographer should know the benefits and shortcomings of each metering mode and pattern. The more crayons in the box the better. That said, when using manual mode the photographer becomes highly cognizant of both light quality and quantity.

Best,

Chas

Blake Shadle
03-31-2008, 11:38 AM
With regard to metering, it really matters not the method used, as a firm understanding of exposure should allow the photographer whatever the meter pattern or method used to render the subject as desired. No one method is best for all scenarios, a competent photographer should know the benefits and shortcomings of each metering mode and pattern. The more crayons in the box the better. That said, when using manual mode the photographer becomes highly cognizant of both light quality and quantity.

Best,

Chas


Well put, Chas, and I have to agree.

Lance Peters
03-31-2008, 06:03 PM
Hi - been reading this with intrest, I am certainly no expert - however I am finding that I am getting much better results with all types of photographs) using Spot Metering and the zone system. Mind you if I have nothing to do, I will go out and just take random shots of anything to practise using this system. I have blinkies turned on and use the histogram to confirm the correct exposure.

So basically - zero out the meter on a neutral tone - then change shutter speed/aperture to add remove light depending on the main subject. +2 stops for bright white with detail -2 stops for black with detail.

Photoshop Cafe have a very very good training DVD - " Perfect exposure for digital photography - the zone system of metering and shooting" gives a very good explanation that is easy to understand. I found it to be excellent, whilst it uses spot metering the understanding of how it all works is invaluable.

Artie and Staff - this sort of video / training DVD is what a lot of people need, a version targetting bird photography would be surely be a big seller - I'd buy one.

Lance

Alfred Forns
03-31-2008, 07:55 PM
Lance that is one way of doing it !!!! I did use and teach the zone system in B&W

No doubt you will have good exposures but it is too slow When I was with Canon and had the Mk3 I was able to remove the spot meter from the selections and just left multi and manual.

One thing to note with the zone system It was used along with developing to produce results There was a way to contract and expand the scene to fit on the paper. With the digital capture you don't have that. If the range is over what the sensor can capture no amount of + or - will give you a good histogram !!!

The bottom line is to understand what you are doing and make good decision ..... and by the way understanding the zone system will get you to understand exposure !!!

Lance Peters
03-31-2008, 08:02 PM
Hi Alfred - Yes it is slow, but I am finding it useful to get that understanding of exposure.

I am guesiing it is not too much different to what you are saying in the tutorials here about exposure - EXCEPT you are using matrix metering and AV mode - the rest of the theory about adding/subtracting light would be similiar???

Is my understanding correct?

Thanks

Lance