Fujifilm Provia 100F (RDPIII) vs. Provia 400X (RXP)

In this day of insane ISO settings on digital cameras ISO400 may seem so trivial as essentially indistinguishable from the base ISO setting. If you still use film and rarely deviate from ISO50, though, then ISO400 can make quite a bit of difference in certain situations. I have long found that it is particularly useful when I want to shoot handheld with my Hasselblad 503CW camera and have decent depth of field, or when shooting landscapes in diminishing light using small apertures for sufficient depth of field and still having fast enough shutter speeds to freeze motion within the frame.

When I first thought of using an ISO400 slide film, Fujifilm Provia 400X was a natural choice given how fond I am of Fujifilm Velvia 50 and Provia 100F. If anything, I sort of expected Provia 400X to be quite similar to Provia 100F, only two stops faster. Having used Provia 400X for a number of years, however, I have always felt that its colour reproduction is quite different from any other Fujifilm transparency. Recently I went again to Mount Putuo—a small, nice island not far from Shanghai—and, as the light was not exciting enough for exhilarating landscape photography, I decided to use the opportunity to compare the two Provias.

Technical specifications of Provia 100F can be found here, and those of Provia 400X here. Among the aspects of real consequence to photographers I would mention the following:

Provia 100F has noticeably finer grain than Provia 400X: RMS granularity value, a widely used standard for measuring the degree of grain in photographic film, of the two films is 8 and 11 respectively (the lower the RMS number, the smaller the apparent grain). Looking at slides with a 10X loupe reveals visible difference in graininess in favour of Provia 100X. But this, of course, should be expected given that Provia 100F is a slower film.
Provia 100F has better reciprocity failure characteristics: while Provia 100F does not necessitate exposure increase for exposures of up to 4 minutes and requires a +1/3 exposure increase for exposures between 4 and 8 minutes (it is not recommended for longer exposures), Provia 400X requires exposure increase of 1/2 stops at 2 minutes and an increase of 1 stop between 4 and 8 minutes. With this being said, Provia 400X is two stops faster, so if you shoot at the same EV and exposure time is, say, 4 minutes for Provia 100F, it will be 2 minutes for Provia 400X, so the difference is not that big.

Testing procedure was quite simple: I loaded one film back with Provia 100F and another with Provia 400X, and then shot each scene with both films at the same aperture, changing shutter speed to take into account the difference in film speeds. The camera (Hasselblad 503CW and CFE 2.8/80 lens without any filters) was on a tripod, a cable release was used, and ambient light was stable. I scanned each pair of shots as one image, made basic adjustments in Photoshop (levels only), and only then cropped and resized them for presentation here. Thus, the test images below preserve relative colour reproduction of the two films. To my eye, they look nearly identical to the original transparencies (this will not be the case if your monitor is not calibrated).

Fujifilm Provia 100F (left) vs. Provia 400X (right): test image #1

Fujifilm Provia 100F (left) vs. Provia 400X (right): test image #2

Fujifilm Provia 100F (left) vs. Provia 400X (right): test image #3

Fujifilm Provia 100F (left) vs. Provia 400X (right): test image #4

Fujifilm Provia 100F (left) vs. Provia 400X (right): test image #5

Fujifilm Provia 100F (left) vs. Provia 400X (right): test image #6

You can draw your own conclusions from the above images, but here is what I observe:

Provia 400X delivers notably darker images, which may work for or against your photographs depending on the subject. I find the darker rendition of Provia 400X quite attractive for late afternoon photography or expressing brooding ideas but, having looked at various types of images from both films, I overall prefer the clarity and brilliance offered by Provia 100F.
Dynamic range (latitude) of Provia 400X is noticeably narrower than that of Provia 100F, and shadows drop to black considerably faster. Provia 100F captures considerably more shadow detail.
As far as colour reproduction goes, Provia 400F has a distinct red cast in relation to Provia 100F (or Provia 100F has a perceptible cyan cast in relation to Provia 400X, if you will). While adjusting the Cyan/Red slider of Colour Balance by -15 points brings colour rendition of images shot with Provia 400X much closer to that of Provia 100F, subtle differences in colour reproduction remain and are difficult (perhaps impossible) to fully eliminate in Photoshop.

Although both films bear the name of "Provia", there are considerable differences in how they render the world. All things considered, I find the lighter, less red rendition of Provia 100F more appealing. Nonetheless, Provia 400X is a very competent option when ISO400 speed is needed.

Related article: Fujifilm Astia 100F vs. Provia 100F