Going from LR to Photoshop and back... file conversions...

[splproductions]

My typical workflow involves doing some fairly standard things like adjusting WB, sharpening, etc, in LR. Then sometimes I'll bounce it over into Photoshop to touch things up, edit eyes, etc. I then hit "Save" in Photoshop so it pulls a new copy with my edits into LR.

When I do this, the new file is no longer .dng, it's .tif.

I just read a post here on TPF where someone said that when you convert to .tif, you lose things like "accurate and adjustable white balance adjustment". Is this true, and are there other things I lose? So should going into Photoshop to make edits be the very last thing I do in my workflow?

 

[Garbz]

Whitebalance is adjustable in that the sensor has a certain calibrated value. I.e. in Lightroom it knows that with the RAW data from Camera X setting the white balance to 5500k with -2 tint provides a certain colour curve to the image. It is also capable of reading the camera's "as shot value". The data Lightroom works with is the RAW sensor data. It does so in a linearised way before the standard gamma curve is applied (which is necessary to make images look like real images).

TIFFs on the other hand have a colour profile of the native working space (typically sRGB, Adobe RGB, or ProPhotoRGB). The tools in Lightroom work with these files differently, and the white balance is one of them. As TIFF doesn't have a concept of white balance the sliders for white balance can't be set in kelvin values anymore.

Do you lose anything? Not really. TIFF is a 16bit format, your RAW data is typically 10-14bit depending on cameras. TIF actually has more possible values to identify a colour with than your RAW sensor data. This means you can still get the same effect as changing the colour temperature by sliding the sliders in Lightroom around, except that you can't set presets like Daylight, Sunny, Cloudy or anything like that.

You do however lose one thing, and that is because of the way Lightroom works with files. The RAW process is non-destructive. A RAW file is in its original glory and the Lightroom data base holds a list of all the settings applied to it. You can go back and change these settings without issue any time you like. Once you export to Photoshop however Lightroom rasterises the image and applies all changes to generate the TIFF file. These changes are now permanent as you can see when you click on the TIFF in Lightroom, all the sliders are at 0. At this point you can not change the noise reduction applied earlier, or undo the sharpening, or change the camera colour profile, or in the case of editing a black and white image your colour data is completely lost.

As such don't go to Photoshop until you're done in Lightroom, or if you're worried, turn noise reduction and sharpening off. As mentioned TIFF can store a lot of data so you can always apply these two destructive settings later in Photoshop or Lightroom, but in the interim you should have no problem with adjusting the colour or tone of an image after you're in the TIFF stage.