RAW question

[ty_mixon]

Just a quick glance at PS3's raw processor, and it seems that you can 'fix' any

mis-setting that isn't physical.

 

By physical I mean Aperture, Focal Length, Exposure Time. But it seems any

setting on the camera could be changed in post.

 

So what are the limits of RAW? How much can I fix, or adjust, or just play with

the settings so that I can see what my photo would look like if I'd used a

different setting?

 

Thanks!

[keith_clementson]

It's non-destructive so you can push the limit of curiosity. With the "exposure" and "fill" and

"temperature" sliders, you'll find you have more latitude than you imagined - surprisingly

enough safety net for many brain burps and camera errors. You'll almost start to think it's

unfair. Do most post CS3, though, as the adage goes. But, of course, your best work is your

best capture.

[marc_rochkind]

You're on the right track, Ty... few camera manuals state exactly which settings apply to JPEG only, but you might look in yours anyway.

 

It's not so much that you're changing them when you process the raw file. Rather, they were never set in the first place. Sometimes certain settings are recorded in the raw file (e.g., white balance), without actually causing a change to the image itself, and sometimes processing programs, especially those from the manufacturer, make use of these for an initial processing state. So, it might seem like you are changing them.

 

In my own workflow, I always use 3rd-party raw processors (Lightroom, nowadays), and I don't even bother to set any controls in my camera other than what you refer to as physical controls (that is, the ones that were on my 1964 Konica FP).

[saskphotog]

Yes, Ty, you seem to have had an epiphany.

 

That, in a nutshell, is the whole reason for shooting Raw.

 

I just want to add one thought; almost all Raw processors can do batch processing to any images you pick, with any settings you want to use, and then repeat it with a whole new set if you choose.

 

Raw is a powerful tool.

[mendel_leisk]

"So what are the limits of RAW"

 

Maybe one or two stops latitude, at most. If you've got totally blown highlights, for example, no amount of post processing is going to recover anything: white is white.

[ronald_moravec1]

One should not depend on raw to correct bad exposures. It has lots of virtues as said above, but fixing bad exposures more than a little is not one of them.

[ambers-photos]

i have found you cant fix over exposure but under exposure it works pretty well

 

Amber

[mendel_leisk]

"i have found you cant fix over exposure but under exposure it works pretty well"

 

True. Bad overexposure is *gone*. But underexposured areas usually have info that can be pulled out. Adobe Camera Raw's "Fill Light" slider is good at this.

 

A good tact for ensuring recoverable raws is to set a slight negative bias to the auto exposure. I don't think you want to do this all the time, and especially not for beach/snow scenes. But with variable contrasty light, a 1/3 to 2/3 negative exposure compensation will reduce the odds of blown hot spots.

[philippartridge]

Since we got into technique, I flirt with over-exposure all the time, since it is the best technique for capturing the most data (expose to the right). I rely on the LCD to detect blowouts, mostly these are specular in nature, but sometimes I lose more than I can see with harsh sun, and the not-so-good screen. I figure on retrieving around a half stop easily, and above that it degrades until at a stop over, it is quite poor. The reason for this is that RAW s/ware can retrive data even if only one channel is still in scope in the over-exposed content; the other two can be extrapolated.

 

My RAW converter, Capture NX, has nifty control points which work in tandem with the exposure control to bring back h/lights up to this point.

 

I shoot mountain scenery, almost always very high contrast - I would never deliberately under-expose, digital or film, neg or slide - you just lose too much in the shadows.

 

Another thing with RAW, you may set up your in-camera parameters for high sharpness and low contrast. It will look like shite on the LCD, but you will (i) be able to see if the shot is sharp, and (ii) capture the broadest dynamic range possible. The image comes alive in the software; to be clear, WB is just another setting you can change after the event.

 

Lastly, I detect that some posters believe there is a 'correct' exposure for all images. I disagree, there is almost always a *band of acceptability* in exposure (latitude), the choice is up to the taste of the photographer, and his/her aim (moody or well lit) for the end product.

 

Raw is amazing. Best regards.

[the black rabbit]

The whole point of shooting in RAW [apart from the non-destructive element and the white ballance issue] is to retain the information in the shadows that would be 'cut away' in a jpeg compression. So you will always retain more detail in your shadow areas due to the information being present [12-14 bit]. You can then expose for the highlight detail to compensate for digitals' low dynamic range in order to bring the detail back into the highlights.

 

Thus your underexposure isn't a problem, and over exposure ultimately is.

 

Obviously you must try to get an even lighting but with RAW you should be able to edge the histogram closer to the right and still retain a lot more shadow detail.

[ty_mixon]

Thank you for all of the responses. It's been very informative.