Ilford FP4+ 125

created/modified 2018-03-03

Ilford FP4+ 125 B&W Film Profile/Review

This tech page is for Ilford FP4+ 125 Film, or 125_FP4PLUS. This is a continuous-tone, panchromatic, all-purpose black & white film with fine grain, medium contrast and outstanding sharpness. Ideal for most shooting scenarios in good light conditions. It is available in 35mm roll, 120 roll, and a variety of sheet sizes all the way up to 20×24 inches. This film features medium speed (ISO 125/22° in most developers), high sharpness, fine grain, and high exposure latitude. Ilford has produced this emulsion for quite some time and has continually updated it over the years.

Having shot some of this film for this write up, and looking at it up close an personal, I very much am of the opinion that this emulsion is Ilford’s “universal” general purpose film. It’s medium speed, you can get it in pretty much any size, it has totally acceptable resolution, grain, and exposure latitude. It is very predictable and well behaved in pretty much any developer you throw at it and is easy to push or pull process with very good results. Looking at the images I shot with it outside of the images shot to create the characteristic curve, they’re all very pleasant and nice to look at. There isn’t anything that’s totally exciting about how it looks, but at the same time, there is absolutely nothing to complain about. All in all, a good medium speed all-rounder film that will let you consistenly and reliably create great images.


There are many ways to develop 125_FP4PLUS. Following Ilford’s recommended development in their technical information sheet on their website is a good place to start if you’ve not developed this film before. If you send your film in here to Simple Film Lab, we develop 125_FP4PLUS with replenished Kodak XTOL with constant rotary agitation as standard practice. The standard development time is 7:00 at 75 degrees Fahrenheit. We use a 1+4 water+vinegar stop bath between development and fixing. We fix all BW films in Kodak Fixer.

Exposure Guidance

There are many ways to meter and expose 125_FP4PLUS. If sending 125_FP4PLUS in to Simple Film Lab to process and scan, we recommend taking an incident light reading of the darkest part of the scene you want to retain details in and subtracting 2 stops of exposure from that reading. For example, if the darkest part of the scene that you want to retain detail in reads 1/125 shutter, f/4.0 at ISO 125, either set the shutter to 1/500 or close down the aperture to f/8.0, or a combination of the two to reduce the exposure by two stops. If you don’t have a light meter, then set your camera exposure compensation to +1 stop, and that will generally result in an acceptable exposure for most situations once scanned in and density corrected. If you want to add a stop of shadow information to the image, then place the darkest part of the image you want details in one stop down from the meter reading instead of two. 125_FP4PLUS has enough highlight exposure latitude that this is safe to do and still retain good highlight information for pretty much anything except the highest contrast scenes.

Characteristic Curve

Using Simple Film Lab, here’s the characteristic curve for 125_FP4PLUS overlaid with the Ilford standard 0.58 Contrast Index that it is scanned in with:


The scale along the bottom is exposure EVs, the scale along the left is the measured density as seen by the film scanner, meaning raw ADC values. The EV 0 mark is an 18% exposure card exposed correctly via an incident light reading with a Sekonic light meter through a T-Stop rated lens. Every dot along the curve is a full stop of light. The black curve is Contrast Index that the emulsion is digitized and linearized with, the green curve is the actual measured density values of the emulsion using the development described above.

Dynamic Range/Exposure Latitude

125_FP4PLUS has excellent dynamic range. Following the development practice described above and scanned in with the Ilford standard CI 0.58, the film base plus fog starts to happen at EV -5 and is still going to clear film base all the way out to EV -8. 125_FP4PLUS has a very long toe. According to Ilford, you can push FP4 6(!!!) stops. On the highlight side, with replenished XTOL it pretty much hits maximum density by +9 EV.

With the above information, in Adobe Lightroom, the visible dynamic range of an exposure is +7 EV to -6 EV. 125_FP4PLUS provides about 1 stop of under exposure and 2 full stops of over exposure protection while still maintaining acceptable black levels and full highlight retention for the full visible dynamic range in Adobe Lightroom with no change in development. These over-under limits can be exceeded if you are OK with reduced performance at the extremes of the exposure scale. This equates to an approximate exposure index range of EI 50 to 200, which is excellent. Push processing will result in bringing the toe contrast up and providing more shadow detail, but at the expense of highlights and a much higher contrast index.


125_FP4PLUS has good resolution for a 125 speed film. Ilford Photo does not publish an MTF curve for 125_FP4PLUS in it’s technical information sheet, however looking at images made with the film, I’d say there is absolutely nothing about the resolution of the emulsion that I would complain about. I’d rate it as high middle of the road. Given that you can get it in such huge sheet sizes, the resolution really only matters in the smaller formats. In 120 roll format and larger it’s totally a non-issue.

In terms of grain, it’s fine grained. In 135 format, it’s visible, but pretty pleasant with replenished XTOL. As you get into larger frame sizes, the grain will become less and less visible. In 135 format at 8×10 print sizes, there is nothing about the grain that would give me pause. At that size, it’s just barely visible and very pleasant.

Sample Images

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Here’s a Flickr Album of images shot on 125_FP4PLUS. I’ll add more images as I upload them to Flickr.

Downloadable Sample DNG Files

As part of this tech sheet/film review I’m making a ZIP file available that contains some Adobe DNG files that are a sample of what you would receive if you sent your film into Simple Film Lab to process and scan. It’s relatively large, but if you want to see what you can get, worth a look. Click Here

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