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JPEG Tone Curves / Dynamic Range

Our Dynamic Range measurement system involves shooting a calibrated Stouffer Step Wedge (13 stops total range) which is backlit using a daylight balanced lamp (98 CRI). A single shot of this produces a gray scale wedge from the camera's clipped white point down to black (example below). Each step of the scale is equivalent to 1/3 EV (a third of a stop), we select one step as 'middle gray' (defined as 50% luminance) and measure outwards to define the dynamic range. Hence there are 'two sides' to our results, the amount of shadow range (below middle gray) and the amount of highlight range (above middle gray).

To most people highlight range is the first thing they think about when talking about dynamic range, that is the amount of highlight detail above middle gray the camera can capture before it clips to white. Shadow range is more complicated; in our test the line on the graph stops as soon as the luminance value drops below our defined 'black point' (about 2% luminance) or the signal-to-noise ratio drops below a predefined value (where shadow detail would be swamped by noise), whichever comes first.

Note: this page features our interactive dynamic range comparison widget. The wedges below the graph are created by our measurement system from the values read from the step wedge, the red lines indicate approximate shadow and highlight range (the dotted line indicating middle gray).

The X-E1's default tone curve is identical to the X-Pro1's, and offers a good highlight range of about 3.7 stops, with just enough of a roll-off into the highlights to prevent harsh-looking clipping. This places it marginally behind the likes of the Sony NEX-7 and Olympus OM-D E-MF. However, the Fujifilm's DR expansion modes are particularly efficient in the highlights and at the DR 400 setting you gain almost an additional 2 stops of highlight range.

Film Modes

The X-E1's color Film Simulation modes show subtly different tone curves, which translate into visible real-world differences. Velvia/Vivid is very contrasty indeed, clipping more abruptly to both white and black, while Astia/Soft echoes Provia/Standard across the highlight range but is more contrasty below middle gray, resulting in somewhat deeper shadows. The Pro Neg Hi mode lies somewhere between Velvia and Astia in terms of its shadow contrast, while Pro Neg Std closely matches Provia/Standard. Likewise, the various Monochrome modes all match Standard exactly.

Dynamic Range Expansion Modes

Like the X-Pro1 the X-E1 has two dynamic range expansion settings to bolster its highlight range: DR200 (200%) adds an extra stop of information in the highlights, and DR400 (400%) adds two stops. Technically, the camera achieves this by applying less amplification to the sensor's output than usual prior to AD conversion to avoid clipping highlight data, then pulling-up the midtones to the correct brightness in JPEG processing. This is essentially the same process as Canon and Pentax use for their highlight-expansion modes.

An alternative way of thinking about this is that DR200 is like underexposing a stop to retain highlights then adjusting the brightness afterwards, and DR400 is like underexposing by two stops and adjusting further. Because of this, the minimum ISO available in each mode is limited: ISO 400 at DR200, and ISO 800 at DR400. The flipside to this approach is shown by ISO 100, which is effectively the opposite; i.e. ISO200 overexposed by a stop then pulled-down in processing. This results in the loss of stop of highlight range - to all intents and purposes it counts as DR50, and should therefore normally be avoided. (Note ISO 100 is only available in JPEG anyway).

In this comparison we can see the impact the DR setting has on highlight range. DR200 offers a huge 4.7 stops of highlight range, and DR400 goes another stop beyond this, disappearing off the scale of our graph. Note that this advantage isn't just for JPEG shooters - it extends to RAW files too. On paper at least this is very impressive indeed; we'll see how it translates into real-world results in the final review. The Fujifilm X-E1 also comes with the same Shadow and Highlight Control functions as the X-Pro1. You can read more about this feature on the dynamic range page of our X-Pro1 review.

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Comments

Total comments: 13
Mentt

Hello, can you help me with deciding between FujiFilm X-E1 and Canon 600D with set lenses? Size and weight is no concern. Which camera has better image quality and which one is more versatile ?

0 upvotes
BobFoster

I have had this camera for almost 3 weeks already and I also can’t figure out how to set the minimum shutter speed when using auto ISO, can you shed a light on that?

Thanks!

1 upvote
Menneisyys

I use the quick shortcut assigned to the Q (or Fn? The one next to the shutter button) button. There, you can quickly change the minimum shutter speed while using auto ISO.

0 upvotes
kreislauf

why was the X-E1 picture taken with a 35mm lens while MFT had the 50mm mounted and FF like A99 or 6D had 85mm???

1 upvote
Menneisyys

The 35mm F1.4 and the 60mm F2.4 Macro (the only two normal / short tele primes at the time of writing) are about equally sharp at f/5.6 and f/8 (see http://slrgear.com/reviews/showproduct.php/product/1487/cat/105 and http://slrgear.com/reviews/showproduct.php/product/1486/cat/105 ). In addition, the 35mm doesn't exhibit much field curvature, unlike, say, the latter-released 27mm/f2.8 pancake (more info on this problem: http://www.photozone.de/fuji_x/855-fuji27f28?start=1 )

0 upvotes
Menneisyys

(cont'd)

Finally, now that the absolutely stellar (see http://slrgear.com/reviews/showproduct.php/product/1674/cat/105 ) Fujinon XF 56mm f/1.2 R is out, non-macro people able to shell out the double the price generally prefer it to the old 60mm F2.4. (Of course, this may not have been a point in choosing the 35mm over the 60mm back then. Nevertheless, we are pretty lucky to have a studio shot demoing the field curvature / sharpness of prolly the most popular Fuji X prime, and not that of one that has since been overshadowed by a newly released one.)

0 upvotes
pscharles

continuing my post . . .

I understand why Fujifilm designed the lens rings with those slim grooves for stylistic reasons, but I find myself frequently turning the wrong one because they all feel the same. I'll get used to it, but a rubber ring on the zoom would help. Also, the zoom ring is stiff and those little grooves are slippery. Rubber would help the grip.

I would suggest turning off the image display as the default is 1.5 seconds. The image display clogs up the EVF for 1.5 seconds making it impractical to follow action. It's in the menu under setup screen 2.

1 upvote
pscharles

Had mine a short while, purchased in part due to this review.

A couple things worth mentioning in terms of this review. The exposure compensation dial on my camera has a very firm detent so there's no chance of an inadvertent movement of the dial. I've loaded body firmware 2.0 and 18-55mm lens firmware 3.0. According to Fujifilm, these updates are supposed to address a number of issues, including the slower focusing. I find the camera/lens focus speed to be quite good with this update in place.

0 upvotes
lbpix

Had my xe-1 2 weeks now and I'm blown away by the quality of the images taken with the kit zoom lens. The images could easily be printed at about 50" and are in practice comparable to my D800. AMAZING!
In use too I love it. The EVF whilst not as clear as an SLR viewfinder, tells me all I need to know and enables me to see all the menus without putting on reading specs. I use it exclusively in EVF mode. It is light and handles superbly. The image stabilisation seems incredible- so far, as good as the D800 shots from a tripod! If you're in doubt, go and buy one.

2 upvotes
Deardorff

Can the back screen be turned off completely so only the electronic viewfinder is used for composing and shooting?

0 upvotes
vratnik
0 upvotes
newtonseye

when you say ":but powering off usually cleared the error." can you expand a bit on that. Was there a different fix at another time?

0 upvotes
Deardorff

What about shutter lag? Any appreciable delay from the time one pushes the button til the shutter actually releases?

0 upvotes
Total comments: 13