Film Friday - November 15th, 2024. Rollei Ortho 25 Plus

Welcome to the Rollei Ortho edition of our Film Friday reviews. Today we are going to cover Rollei’s Ortho 25 Plus emulsion, which is part of that relatively small group of orthochromatic films available on the market.

There are a few different ways we could approach describing this film to you. We are going to start from the perspective of what this film means to the “everyday” day photographer before moving into a more technical explanation. We are taking this approach under the assumption that if you are reading this it is likely due to an interest in wanting to use the film yourself, and for that we want to fill you in on what to expect.

So here is the first thing to know about Rollei Ortho 25 Plus: it’s slow. Super slow. ISO 25 slow. It is one of the slowest speed films you can easily get ahold of to load in your cameras. There are some benefits to this slow speed, namely fine grain. So yes, Rollei Ortho 25 Plus is superbly slow but it is also superbly fine grain. Here at the shop we happen to be fans of film grain. Grain is the building block of the analog image, akin to the brush strokes of a painter. But not every photographer enjoys the aesthetic of grain, or doesn’t enjoy it in all situations. If you are a fan of fine grain then you and Rollei Ortho 25 are about to become fast friends. Even in the 35mm format, Rollei Ortho 25 has barely perceptible grain and if you load it in a medium format camera then you can forget about film grain entirely. We tried to print a Rollei Ortho 25 negative in the darkroom a while back and had a devil of a time using a grain magnifier to focus the image because even with the magnifier there was no visible grain to focus!

Like your images super smooth and free of grain? Shoot Rollei Ortho 25. Image courtesy of Cameron Moon and made with a Hasselblad 500C.

Of course, there are other benefits that film as slow as Rollei Ortho 25 can offer. It can be ideal if you have a fast lens that you want to shoot with wide open apertures on bright days. Normally the abundance of light and higher ISO of faster films would require stopping your aperture down. But what about when you have that awesome 50mm f1.2 lens and you want some lovely bokeh in your image? There are a few solutions but one of them is definitely slower film. Even on a totally sunny day shooting wide open should be achievable with a film as slow as Rollei Ortho 25. And then the other advantage is the greater ease with which longer exposures can be achieved. Without piling on strong ND filters faster films normally cannot do shutter speeds much faster than an 1/8th of a second or so during the day. But pair Rollei Ortho 25 up with f22 and throw in a polarizing filter (which you likely already own) and you can pretty easily make that 1 second exposure of the waterfall in front of you.

If you are a fan of daytime long exposures, Rollei Ortho 25 can help you get there. Image made with a Hasselblad 500C.

After its slow speed and super fine grain, the next quality of Rollei Ortho 25 to have on your mind is its contrast. By nature orthochromatic films are of higher contrast. They tend to produce images that shift from black to white very quickly, have deep shadows and bright highlights. This can create images that have more drama to them, but it can also lead to a harsh feeling as well. Rollei Ortho 25 may not be as high contrast as you might expect, but it does still have higher than average contrast. Use it in soft lighting and it can add a nice punch to the images you make. Use it in dramatic lighting and it will further emphasize that drama. Use it in harsh lighting and you can produce a very graphic image lacking much in the way of midtones.

An interesting thing about Rollei Ortho 25’s contrast is that it is pretty flexible and highly dependent upon the developer and developing technique. Rollei themselves produce a few different developers for this film which produce different levels of contrast. For example, if developed in Rollei’s Low Speed developer the Ortho 25 has reduced contrast and better mid tone gradation, producing a look similar to the famous Kodak Technical Pan film. Or if paired with Rodinal, a developer known for sharpness, the high resolution of Ortho 25 is taken even further and even greater detail in your images is the result, at a tradeoff with higher contrast.

The takeaway here is that it is likely your Rollei Ortho 25 images will tend toward the higher contrast side but if you like to tinker with film developing you can go a long ways in terms of tweaking Rollei Ortho’s contrast to your preferences.

Rollei Ortho 25 is a film that naturally has higher contrast, which leads to deeper shadows and highlights that pop a bit more. Even when used in the softer light of open shade the images have a punch to their contrast. Image made with a Canon AE-1.

And that brings us to our last selling point for the everyday film photographer: the ortho look. Rollei Ortho 25 Plus gets its name from the fact that it is an orthochromatically sensitive film. In short this means the film is mostly sensitive to only blue and green light (with a bit of yellow thrown in) but is blind to orange and red light. The effect this has on your photos will be that blue and green objects essentially overexpose, and are rendered as lighter shades of grey, moving toward white. Meanwhile orange and red objects underexpose, turning into darker shades and moving toward black. Think of it this image: you have a red rose surrounded by green leaves. With normal panchromatic film these two colors are rendered into shades of grey largely based on how bright they are. If that red rose is the same lightness as the green leaves they will both render as close to the same shade of grey. With ortho film though those green leaves will overexpose and render as light grey, while that red rose will underexpose and render as a dark grey. In this example that red rose will distinctly stand out from the lighter toned leaves around it. With ortho film then look for these contrasts. Caucasian skin tones have a lot of red in them so ortho film will darken many skin tones, but blue eyes will render lighter. Green vegetation can start to take on a snowy look similar to how it renders in infrared. In many cases the different perspective of ortho film can be slight, but if used deliberately it can produce some distinctly different images from its panchromatic brethren.

In this portrait our cooperating photographer model has bright red hair, which Rollei Ortho 25 darkened up quite a bit. Image made with a Hasselblad Flexbody.

And here you have a footpath in nearby Forest Park surrounded by lush, green vegetation that is rendered considerably lighter by Rollei Ortho 25. Image made with a Hasselblad 500C.

So what else is there to know about Rollei Ortho 25 Plus? Well, there is a bit more technical info we can share with you and a bit of history too if you care to know. Let’s start with the technical stuff.

We talked about Rollei Ortho 25 Plus’ fine grain already. Oftentimes fine grain is linked to high resolution. It is not a direct correlation mind you, but it certainly helps a film resolve finer detail. There are other factors that work into this such as local contrast, developer, and so forth. Suffice it to say though that Rollei Ortho 25 Plus could easily be the sharpest film you have ever held in your hands. Yes, there are sharper films out there but it is a short list and most of those films tend to be scientific or graphic films that have very little in the way of tonality. One film that you may have already shot that is famous for its high resolution is Kodak TMax 100. This film has made a name for itself as being one of the most detailed films out there and is frequently used by photographers who want to test the sharpness of a lens since TMax easily outperforms many lenses in terms of resolution. Well, Rollei Ortho 25 is on a whole other level. Kodak TMax 100’s data sheet rates the film’s resolution at 200 lines/mm. Rollei Ortho 25 Plus has a resolution of 330 lines/mm. While these numbers need to be taken with a bit of a grain of salt and some understanding of how they are measured, it is sufficient enough information to know that the only thing holding back detail in your Rollei Ortho 25 images is going to be the quality of your lens, and not the quality of your film.

If you have read many of our Film Friday reviews you know we always like to touch on reciprocity failure with the films we cover. We do a lot of ultra long exposure work, so reciprocity compensation is quite familiar to us. Unfortunately there is not much info out there regarding the reciprocity failure rate of Rollei Ortho 25. Our experience has been that the usual amounts of compensation we do is enough for this film and that has been validated to some degree by other Rollei Ortho 25 users suggesting adopting the compensation rates of other similar speed films like Rollei RPX 25. While we cannot give you a super definite chart to swear by, we recommend that no compensation is needed for 10-15 second exposures (you can give it an extra 1/3-1/2 stop if you want but generally negative film will cover this bit of underexposure fairly easily). At around 30-60 seconds it is a good idea to give Rollei Ortho 25 Plus an extra stop of exposure, so that calculated 30 second exposure really ought to be a 60 second exposure, and so on.

We do love our long exposures. Thankfully Rollei Ortho 25 Plus seems to have fairly normal reciprocity failure. This 2 minute exposure included only about 1 stop of additional exposure added atop the initial meter reading. Image made with a Hasselblad Flexbody.

And that more or less concludes the sum total of our experience and research into Rollei Ortho 25 Plus film. We hope it has not only been informative but has sparked your curiosity enough to try a roll of this film. It is definitely a different flavor of film from that which we usually shoot with, both due to its ultra low speed and orthochromatic sensitivity, but it is a good thing to vary your routines, to experiment, and to make good use of the variety of film stocks that are available to us film photographers.

So why not pick up a roll of Rollei Ortho 25 Plus? You can do so pretty easily with this link right here. Go have some fun with it and let us know if you get any great images!

As always, we will close out this review with a few more of our favorite images made on Rollei Ortho 25 Plus.

That high contrast and drama that Rollei Ortho 25 Plus is capable of. Image made with a Yashica Dental Eye III by Jackson Keller.

Rollei Ortho 25 Plus and the Hasselblad Flexbody meet again.

Co-worker portraits are always easier when your co-workers are photographers. Image made with a Canon AE-1.

Image courtesy of Cameron Moon and his Hasselblad 500C.

A macro image of a lighting filament thanks to Jackson Keller and a Yashica Dental Eye III camera.

When we were first acquainting ourselves with Rollei Ortho film we sent a roll to a good friend of the store, Paul Barden, who shot it and processed it in Pyro developer. Paul’s image shows how tonal and delicate Rollei Ortho can be.