Exposure information?

[brucehughw]

Hi, everyone.

Is there any way to get exposure information for images posted in this and other forums?

Thanks, Bruce

[Manfred M]

Yes, view the metadata attached to the image. There are a number of plugins that allow you to do just that, but they can be browser specific. If you let us know which browser you are using, some of the members are sure to make some recommendations. I don't use one, so can't help there.

You may not be able to read 100% of the posted images, as some of the posting software does strip out this data.

Just to satisfy my curiousity, what are you expecting to get from knowing this data?

This is probably not the best thread to post this question in, as it could get buried in the postings quite quickly, so I will move it to the "General Photography Discussion" thread, where more people are likely to see it.

[Shadowman]

Some websites like Flickr will have an icon for viewing exif data, here you'll have to ask if it isn't given within the thread.

[FrankMi]

Assuming the metadata is available, it may not be realistic Bruce. Although SOOC images will likely be accurate, when multiple images are combined such as with exposure bracketing or focus stacking, which image from the set provided the metadata?

[brucehughw]

My usual browser is Safari. Sometimes I use Chrome.

As for my interest, I recently started studying exposure value and its use for setting exposure settings. So far it has worked very well. I used an exposure value (EV) of 8 for an indoor hockey game and an EV of 4 for some holiday lights. I guess purists would call these "light values," since I was adjusting the camera's exposure to accommodate these light values. Setting my camera for these values resulted in good exposures under difficult conditions.

Why am I interested in others' exposure settings? Knowing aperture, shutter speed, and ISO, I can easily calculate the exposure value for a given photo and maybe learn from it when I shoot under different ambient light conditions. A single light value, as I mentioned above for those two examples, will make it easy to capture images under these conditions in the future. Rather than remember a series of ISOs, apertures, shutter speeds, I can just remember one light value and adjust for that. It's pretty neat. I'm happy to send some links if others are interested.

[brucehughw]

Thanks. Yes, I know about flickr, and thought this site would have similar information. imho, it would be useful to include this information.

Some websites like Flickr will have an icon for viewing exif data, here you'll have to ask if it isn't given within the thread.

[Stagecoach]

Bruce,

This one for Chrome was recommended the other day by member 'Inkista' Kathy Li

https://chrome.google.com/webstore/d...anjggkmjapkffm

I loaded it as I have recently had problems with Opanda Exif Viewer and found it's fine. Once loaded all you do is right click on the image and select View Exif and you get a nice readout on the right of the screen and a decent histogram.

[GeoBonsai]

There's a bunch of plugins available to view EXIF data in a web browser. I mostly use Firefox with FxIF. On a Windows PC, I don't know about Macs, after you install FxIF, you can right click any image in your browser and select FxIF Data in the option popup, which displays a small text box that contains the EXIF data, if there is any. I really like it when photographers on CiC include camera make, lens, f/stop, and shutter speed with their images, but when they don't, I can peek at the EXIF data using FxIF.

Studying EXIF data has helped me refine my photography technical skills.

[Manfred M]

Bruce, while I understand what you are trying to do, I don't understand why. There is certainly a "correct" eV for a particular scene, but from a compositional / creative standpoint when I shoot a specific image, it's not something I ever consider.

My approach to photographing has tended to be:

1. What ISO is appropriate for this lighting? I will generally choose the lowest ISO value that I can get away with to maximize dynamic range and colour depth and minimize noise. I do sometimes choose auto-ISO when shooting in conditions where the light levels change quickly in a scene.

2. Select whether DoF (shallow or wide) or motion (freeze motion or show motion blur) are my next compositional choice.

3. The shutter speed will be an outcome, rather than a choice, if I shoot for a specific DoF and likewise if I go for a motion approach, the aperture setting will become an outcome, once I select a shutter speed.

So to take your hockey example; regardless if I want a tack sharp image and freeze the player with a high shutter speed or pan along and shoot at a slow shutter speed to get a sharp player, but blur everything around him, the eV will be the same in both instances, but the resulting images will look totally different. Nicely said; I don't care about eV. It is an outcome, not an input.

[Shadowman]

I think awareness or curiosity of another photographer's camera settings is typical as we take our own camera's off AUTO mode. I think that information is more important to an amateur photographer than what camera or lens was used; at least in the early stages of development. Usually it's when the amateur photographer finds out that a perfect exposure can be one of many different (ISO, aperture, shutter speed) settings and each can be used to create a specific effect; then the need to know what settings were used for each particular photo viewed becomes less relevant.

[FrankMi]

Hi Bruce, most photographers would use Manfred's approach as they are maximizing the strengths of the various controls to achieve a specific look as he has described.

Once the ISO, shutter speed, and aperture have been selected for the desired image outcome, I might change the calculated EV value to compensate for situations where the camera's metering can be thrown off by lighting extremes such as night photography, shooting moonscapes, sunrises, and situations where there is a predominance of light or dark such as a close-up of a bright white flower. Often, when the exposure values are extreme or difficult to accurately judge, I'll do an exposure bracketing using -2EV, 0EV, and +2EV but even then, I may shift the 3 (and sometimes 5 bracketed) EV values up or down by 1/2 EV or more.

[Downrigger]

I very much appreciate having access to EXIF data. This is a place for "critical appreciation" (more than "critical evaluation") where I can learn from seeing which elements in the EXIF data have strengthened an image - or not. I use FxIF, and when EXIF data are not available for posted images, I spend less time with them.
Without EXIF there is still something to learn about seeing/conceiving and composing an image, but I, for one, miss seeing the details of execution in such instances to complete my learning and school my appreciation.

[brucehughw]

Manfred (and others), thanks for sharing your approach and comments. I think we're pursuing similar ends, but just going about it differently. By knowing (more or less) in advance how much light I have to work with (e.g., the hockey rink), I can consider my options (lower iso, slower shutter for panning or higher iso, faster shutter speed for freezing) and improve my chance of getting the right exposure for the available light.

For another example, I shot some holiday lights the other night. While keeping the EV to 4, I experimented with different iso and shutter speeds and camera motion, the latter leading to some nice streaks in the images (I'll upload in a few days). Had I not known in advance which EV (again, approximate) to aim for, I would have spent a some time trying different settings (in the cold and fading light, with gloves on/off), checking the histogram, and losing the little light (I wanted some dark blue sky in the background) available after the sun set.

Who knows, I may decide after a few sessions that this approach is too analytical, but for now it works, providing a quick way to determine which iso/shutter/aperture combinations are available. I'm not losing any creativity by it, and it seems to lead to properly exposed images.

Bruce, while I understand what you are trying to do, I don't understand why. There is certainly a "correct" eV for a particular scene, but from a compositional / creative standpoint when I shoot a specific image, it's not something I ever consider.

My approach to photographing has tended to be:

1. What ISO is appropriate for this lighting? I will generally choose the lowest ISO value that I can get away with to maximize dynamic range and colour depth and minimize noise. I do sometimes choose auto-ISO when shooting in conditions where the light levels change quickly in a scene.

2. Select whether DoF (shallow or wide) or motion (freeze motion or show motion blur) are my next compositional choice.

3. The shutter speed will be an outcome, rather than a choice, if I shoot for a specific DoF and likewise if I go for a motion approach, the aperture setting will become an outcome, once I select a shutter speed.

So to take your hockey example; regardless if I want a tack sharp image and freeze the player with a high shutter speed or pan along and shoot at a slow shutter speed to get a sharp player, but blur everything around him, the eV will be the same in both instances, but the resulting images will look totally different. Nicely said; I don't care about eV. It is an outcome, not an input.

[Dave Humphries]

I find being able to view the EXIF data a great time saver whether advising others on their photography or just satisfying my own curiosity. If they haven't said (and many don't think to tell us), I can usually start advising with relevant information, not guessing what camera they've used (re: sensor size and its effect on 'focal length' and DoF), focal length, etc.

Using the link below, not only can I (usually) discover all the exposure data, but also often what lens and PP software they've used, even whether they shot RAW or jpg - all the usual stuff we have to ask, and wait for a reply, before we can really start to help.

Why am I interested in others' exposure settings? Knowing aperture, shutter speed, and ISO, I can easily calculate the exposure value for a given photo and maybe learn from it when I shoot under different ambient light conditions.

Hi Bruce,

It isn't always going to be this simple I'm afraid - the 'browser plug-in' EXIF viewers often won't show whether the exposure you see in the finished image has been increased (or decreased) in RAW converter/image editor.

However, if you paste the URL of a web image into this website, assuming the data has not been stripped, it may well show you that (and one heck of a lot more). It is a 'learning curve' interpreting it though.

http://regex.info/exif.cgi

Cheers, Dave

[Geoff F]

That is the one I use. Just copy the image address and paste into the box. A lot of information can appear, but it depends on the software used for the original edit and some images lose all information.

[Mike Buckley]

for now it works

That's difficult to argue against.

and it seems to lead to properly exposed images.

The single most important capability that leads me to properly exposed images is reviewing the histogram to determine if I need to alter the exposure.

[brucehughw]

Mike,

Re the histogram, if the tonal range of an image does not fill the entire histogram, do you try and expose so that the histogram is biased a little bit towards the right (more exposure and more highlights) or the left? Conventional digital photography wisdom says avoid overexposure, because blown highlights cannot be recovered. This makes sense, but I've found that trying to "bring up" dark tones during post processing (by increasing the exposure) introduces noise into the image, so I make sure that my histograms are shifted more to the right than the left. Any thoughts on this topic?

Thanks,

Bruce

That's difficult to argue against.



The single most important capability that leads me to properly exposed images is reviewing the histogram to determine if I need to alter the exposure.

[Manfred M]

Mike,

Re the histogram, if the tonal range of an image does not fill the entire histogram, do you try and expose so that the histogram is biased a little bit towards the right (more exposure and more highlights) or the left? Conventional digital photography wisdom says avoid overexposure, because blown highlights cannot be recovered. This makes sense, but I've found that trying to "bring up" dark tones during post processing (by increasing the exposure) introduces noise into the image, so I make sure that my histograms are shifted more to the right than the left. Any thoughts on this topic?

Thanks,

Bruce

What you are referring to is often referred to as Expose to the Right (ETTR). It does provoke a lot of discussion and there have been some fairly heated discussions on this site, and others concerning this approach.

You have hit the nail on the head in terms of ensuring that you do not blow out the highlights, but again, this too is open to interpretation. Personally, I don't care if specular highlights are blown out, but this can effect how you expose. Your camera's histogram is based on a jpeg of the image, and your camera is likely to have a bit more headroom (generally at least one stop, but you need to do some testing here) if you are working from RAW data.

As a general rule, I don't bother with ETTR too often. A properly exposed image is generally the key to low noise, regardless of the ISO setting. When I look at the 20,000 to 30,000 images I took over the past year, there is only one instace that comes to mind where ETTR would have been of real benefit from an image quality standpoint. Had I used my "good" camera, I don't think this would have been an issue, but I was shooting with the GX7, which tends to be a bit noiser than the D800.

[Mike Buckley]

Bruce,

I generally try to render a histogram that seems to be consistent with the tones in the scene. As an extreme example, if I was photographing a black wall, I would want the histogram to be mostly on the left.

The best way to eliminate noise is to make an ideal exposure. That means generating a histogram that is consistent with the tones in the scene.

I'm a lot less concerned about noise apparently than most people. First, my Nikon D7000 and my wife's Nikon D5100 have the same sensor model and it has reasonably good control over noise. Second, if I can't see the noise when viewing the image at 30%, I don't try to get rid of it. Keep in mind that very few images displayed on the Internet are displayed that large. If some day I have a need for making a large print that displays noise when being viewed at a reasonable distance (the larger the print, the larger the viewing distance should be), I will deal with the noise at that time.

Hope this helps!

[brucehughw]

Thanks, Mike. Sound advice.

Bruce