Kodak produced a number of interesting film stocks in the late 1980s to early 90s, and among them was the Ektar line of color films (C-41). Kodak replaced Ektar 25 with Royal Gold 25 in 1996. I am not sure how popular ISO 25 color film was then, but here is the product information from Kodak on the Royal Gold 25:
KODAK ROYAL GOLD 25 Film has the same technically advanced characteristics as the film it replaces—KODAK EKTAR 25 Film. Like all ROYAL GOLD Films, it is designed and produced to meet the needs of knowledgeable and discriminating photographers who want more from
photographs than general-purpose films can provide.
ROYAL GOLD 25 Film offers micro-fine grain, extremely high sharpness, and the capability for an extremely high degree of enlargement. The film is designed for exposure with daylight or electronic flash.
Use ROYAL GOLD 25 Film in cameras that allow you to set the film speed manually, or in cameras that will correctly set the film speed automatically from the DX code on the magazine. (Some automatic 35 mm cameras do not read the DX code for ISO 25/15° film and will underexpose it.) This film requires more precise exposure control than general purpose films.
Other features include—
• Extremely high sharpness
• Enlargements of superb clarity
• Incorporates KODAK T-GRAIN™ Emulsions
• Micro-fine grain
• Designed for processing in KODAK FLEXICOLOR Chemicals for Process C-41
• Can be processed with other ROYAL GOLD Films, KODAK GOLD, EKTAR, and EKTACOLOR Films, KODAK Pro Films, and KODAK VERICOLOR and EKTAPRESS
• Built-in dye-masking color couplers
• Provides quality color reproduction without supplementary masking
Basically, it is supposed to be a fine-grained slow emulsion that allows big enlargements. Note the label actually indicated that it was for "SLR cameras." Apparently, it was not aimed at point and shoots of the time.
The thing about using expired films is that in most instances one has little information on how the film was stored over the years. It could have been in a glove box of a car or in the freezer, and everywhere in between. Of course, expired film/distressed film crazies LOVE it when the film's expiredness (is that a word?) shows. While I do appreciate the unexpected results from expired film, I would never use it without testing for shots that I could not duplicate (having learned THAT lesson long ago!) Here is a good thread on Photo.net about Ektar 25
I had some hope for this film, as it was in a lot of expired film at my local camera store. However, it may have come in with someone's bag of camera gear. There were 2 rolls, one in the box, and one in the plastic film can. I chose to use the one without the box. Generally, (at least in the b&w world), slower films retain their speed far longer than faster films. While the rule of thumb that has floated around is to lower the working ISO rating by 1 stop for each decade (i.e., 20 year old 400 speed film = 100 ISO now), slower films usually are less sensitive to the ravages of time.
I shot the roll of RG 25 at the box speed, and took it to Huron Camera in Dexter for processing. When I got the film back, I was a bit surprised as the color shifting was quite intense. In fact, it seemed that it lacked quite a bit of sensitivity, as the negatives are decidedly blue-ish. Reading the photo.net thread given above, I found this nugget: There is a .2 decrease in yellow dye density between 18 and 28 years. Magenta and cyan don't even exhibit a .1 decrease at 100 years. This means the negative appears more blue and the resulting print will be yellow.
So, with regards to this particular film, I would say that it should be shot at ISO 6. I have one box of the Royal Gold 25 left -- contact me if you want it and I'll mail it to you. I also have several rolls of Ektar 25 in 120 in my fridge that came from the fridge of another photographer that kept his film well all the years that he had it. I will give the Ektar 25 a try, but i am not expecting a miracle here. The suggestion from 2005 was to shoot the Ektar 25 at ISO 12. I will use that as a starting point.
Here are the images that follow -- grainy, and due to trying to make the scans look better, there has been a lot of attempted color correction. The negatives of course, were also quite thin. You can see the obvious blue shift that has taken place.