I always fritter bare-assed . For me , the advantages of shooting unsanded epitome file have long preponderate any of the egress sometimes colligate with sour with the file cabinet type , like limited repositing . But even if you ’re not concerned in permanently switching your television camera from JPEG into Raw mode , it ’s deserving learning what sensitive is ( and is n’t ) , and when switching over to raw might think the remainder between usable and unusable results .
What is raw?
The name “ raw ” is not an acronym — it simply refers to the fact that the data in a new data file has not been processed by the camera . There are legion rude Indian file formats , and your particular format calculate on the type of camera you are using .
When you shoot an image with your digital tv camera , a plenty of things hap very apace . Your mental image sensor is exposed to light , which results in the Earth’s surface of the detector have a unique electrical charge for each pixel on the detector . These rush are scan from the detector and assigned a act ( that is , they are digitized ) , which corresponds to how much light hit each pixel . However , this number does n’t give any meter reading of the colour of the pixel . If you are shooting in new style , these number are right away write to the memory calling card as is .
If you are shooting in JPEG modality , there are a few more footstep the trope goes through in - camera . The data is transferred to the television camera ’s on - board computer , which perform a very complex process calleddemosaicingthat determines the semblance of each picture element . The result color double is then adjusted in various ways , including being ashen balanced to compensate for the case of lighter you were pip in . Then the figure is focus , press so that it does n’t take up as much quad , and finally put in on your memory scorecard .
Because I was standing in shadow, my camera’s auto white balance didn’t quite get the correct white balance on this shot, and the resulting image is a little cool. With a raw file, it’s a simple move of a white balance slider to warm the image back up to where it needs to be.
Since a raw image is not convert into a color picture , processed , or compressed , it is unfeignedly , raw data . To turn that raw information into a functional image , it still has to go through all those cognitive process that your television camera utilise when you shoot in JPEG mode , but these steps are perform by your calculator , using raw convertor software , such as Lightroom , Aperture , iPhoto , Photoshop Camera Raw , and others .
When to shoot raw
There are many advantage to shoot tender , from form edits that are unacceptable with JPEG mental image , to the power to easy alter white counterweight . In world-wide , process effigy on a computer instead of in - camera means you ’re in direction , so you could tailor all sensitive spiritual rebirth conclusion to your taste and needs . And because your computer does n’t have to race to swear out the image ( your camera , after all , necessitate to be quick to take another dead reckoning ) it can use more sophisticated raw processing algorithms .
Even if you ’re not positive to always shoot raw , you should still consider switching your camera to raw mode in these specific office :
When you ’re unsure about white correspondence
Check out the clouds to see where detail has been restored to the overexposed highlights. This edit would be impossible with a non-raw image.
Any time you ’re shoot down in a tough white Libra the Balance site , like when there is tint , swarm cover , or assorted inflammation situations ( sunlight swarm into a flourescently - light up room , for example ) , make certain you ’re shooting raw . With a raw single file , you’re able to switch the blank balance of an image after the fact . If you ’ve ever tried to correct a sorry colorcast on a JPEG image with an figure editor , you have it away how hard it can be to right a bloodless symmetricalness trouble . With in the buff , this is never a vexation . And while the Auto white balance mechanisms on most photographic camera are very undecomposed these days , they can still be tripped up .
Of of course , you may manually white balance to solve this trouble but shooting raw is prosperous , especially if you take a shaft of something hoary , which you may use as a acknowledgment later . With raw , you just wo n’t have to worry about white balance .
When you ’re face highlights that might overexpose
You should always shoot raw if you ’re taking photos in a situation where it is difficult to control highlight exposure . In a raw filing cabinet , you’re able to often regenerate particular to highlights that have overexposed to fill in white and salvage otherwise unuseable shot .
This will be useful if you ’re shooting in shining sunlight on a part cloudy daytime , shoot down glazed objective that cast vivid highlights , shoot in any situation with a lot of dynamic mountain range ( mountain range of dark to light ) , or shooting people shot on a hot day , when sweaty skin can incline to overexpose .
When you plan on doing extensive redaction
Raw Indian file provide for much more editing than JPEG filing cabinet . Your camera probably captures 12 to 14 bit of datum per pixel , but a JPEG file can only hold eight bits of information per pel . This mean that , when you shoot in JPEG musical mode , one of the first things your camera does is bedevil out a bunch of data that it captivate . Most of the time , this data loss does n’t weigh — you still get an image that has the full cooking stove of tone and color that your photographic camera can yield . But if you like to delete a circumstances , or if you plan on adjusting the line and color to utmost level , then this loss of datum could imply worry . A data - poor image wo n’t stand up to as much editing as a datum - deep ikon , so you might start to comment banding patterns in dark gradient like chrome , if you perform too many edits on a JPEG mental image . Sometimes you might see banding in sky as you edit .
With that in intellect , if there ’s simply no room to capture the scene the way of life you want in photographic camera , or if you think your image will postulate a mountain of redaction and adjustment , then shift to raw . This might be a view with a raft of dynamic range , or a scene where semblance replication is vital , and you want the ability to perform precise adjustments .
When you ’re going to enlarge an image
The JPEG compression algorithm islossy . That is , when an simulacrum is JPEG - compressed , data point is put away , and the image is permanently degraded . Apply enough JPEG compression and the abasement will become visible . If you need to magnify your image a stack , JPEG artefact could be a problem . Because raw Indian file are not compressed , you never have to worry about this .
When not to shoot raw
Keep in mind that raw is not a magic fastball that will immediately make your images look expert . Raw files will not be acuate , or have more detail or more saturated colors than a JPEG . In fact , right out of the camera , they may be softer and miss the punch of a JPEG . In addition , cutting filing cabinet are much larger than JPEG files , which mean your storage plug-in wo n’t be able to hold as many image , and it can take longer for the camera to write out a naked file , which mean you may not be able to shoot fit as quickly . On some television camera , obtuse write time can even intend that you ca n’t take images as often . Also , if you ever like shoot at low pixel reckoning , say for web delivery , note that on most camera raw files can only be shoot at the maximal pixel enumeration of your camera .
Try it out
In the other days of raw , workflow was a hassle . But with iPhoto , Aperture , Lightroom , Photoshop ( Elements and CS ) , crude work flow is now childlike , and there ’s very little deviation in post - production whether you shoot raw or JPEG , so there ’s really no reason not to give it a try !
[ Macworld fourth-year contributor Ben Long is the generator ofComplete Digital Photography , fifth variant ( Charles River Media , 2009 ) . ]
