Guilty as charged, I am probably in that group, because I've always believed in enlargement limits for every medium.
And that is generally also correct, as every medium has a certain enlargement limit. Which is of course also very dependent on individual preferences (some are more tolerant concerning quality losses of bigger enlargements than other photographers), on viewing distance of course, and as so often, there are also some special exceptions. Which are for example in our case special films like microfilm based films (like CMS 20 II), which have no real enlargement limit (but that special case is a different topic).
But, the interesting point is that due to the huge progress in film technology and lens design in the last decades, 35mm photography has benefitted in a disproportionately high way from this progress. In relation more than medium and large format. Considering our most used applications.
I want to explain that a bit more in detail:
If we are looking at prints, the huge majority is made in formats up to max. 30x40 centimeter. Prints above that size are a very small niche.
And now let's have a look at the year 1985, one year before T-Max 100 was introduced: When we wanted at that time a 30x40 cm BW print with outstanding detail rendition and extremely fine / invisible grain, we either had to use slow-speed 35mm films like Agfapan 25, Ilford PanF, Panatomic X, or we had to use medium format with FP4, Plus-X, Agfapan 100 if we wanted higher film speed.
But nowadays we can have that quality level with an outstanding 30x40cm print already with medium speed 35mm films like T-Max 100, Delta 100 and Acros 100. And with the right developer even with TMY-2 (which is simply a league of its own concerning detail rendition in the ISO 400/27° BW film class, I love that stuff).
No need to have the neccessary compromises of low speed 35mm film, or the compromises of medium format.
In 1985 FP4, Plus-X, Agfapan 100 in medium format was representative for very high, professional grade picture quality. And if we look today at these pictures, we will certainly confirm that it is still very-high professional quality today.
At that time I was a young pupil making his first big enlargements in his own darkroom. From 35mm. Medium format was just a dream for me. The MF equipment was so expensive that I simply could not afford it at all, not even used equipment.
But with the modern, much improved films, and the modern, much improved lens designs, I can now come very close to that former medium format quality level, but with 35mm film. When I look now at my Delta 100, Acros 100, TMX enlargements on 35mm with my best lenses, and compare them to my 4.5x6 and 6x6 shots made on FP4+ or Fomapan 100, then the quality difference is not so big anymore.
In 2019 we were in China, and one part of the journey were the workshops we offered. My part was BW film and development. As I have said above, I often make blind tests with photographers. Did that in China, too.The participants were photo professors and mostly experienced photographers. Presented them pictures made on 6x6 FP4+ with lenses of older design, and 35mm pictures on Delta 100 made with modern lenses. I only told them that some of the pictures were made on 6x6 120, and the others on 35mm. They should say which is which. Almost all selected the 35mm Delta 100 shots as 6x6 shots, and thought that the FP4+ pictures were made on 35mm. They were quite surprised when I revealed the truth

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One big advantage of the newly designed 35mm lenses is that lots of them have a very good performance already at max. aperture. They deliver an optical quality at f1.4, for which the older lenses from the 70ies / 80ies needs to be stopped down to 2.8 to show a similar level of performance. Means that you can use a lower speed, higher quality film instead of a higher speed film with the modern lenses in certain situations.
And if we consider that in medium format 4,5x6 / 6x6 the normal max. aperture for lenses in the mostly used 55-150mm range (35-90mm equivalent in 35mm) is 2.8, but in 35mm it is 1.4 or 1.8, we see that in lots of situations when in medium format an ISO 400/27° film is needed, in 35mm an ISO 100/21° film can be used.
So again 35mm photography has benefitted in a disproportionately high way from technological progress, here modern lens design. Also because we have not seen much new and improved lenses for medium format film cameras in the last 20 years (with the exception of the lenses for the Hasselblad H system).
I enlarge my 35mm pictures regularly to 1.50 meters width. Everytime when I project my slides. The quality with my high-quality projection lenses and the current colour and BW reversal films is simply outstanding. I can goo very close to the screen, can "put my nose" to it, and yet see all the fine details. Tonality and brillance are awesome.
I don't wish for more quality when I see my 35mm slides in projection. I don't miss medium format then.
I do project my medium format slides, too. But definitely
not because I would miss some quality in 35mm projection.
As I have said in one of my earlier posts above: My motto is "horses for courses", the right tool for the job.
In some cases I profit from modern film and lens technology in 35mm. And then I use it and enjoy the results.
In other cases there is no special need for it. For example in lots of my landscape photography. Then
- I am using a tripod in most cases anyway
- can therefore use lower- or medium speed films without problems
- have time, no need for fast reactions
- no need for autofocus
- I am using mostly apertures in the f5.6 - 11 range.
So the advantages of modern 35mm photography are not needed for that. And I can fully exploit the format advantage of medium format, which I do

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Resolution of a lens doesn't matter as much if it's used on a low-res film.
Correct. Fortunately we have today very much films with excellent detail rendition which fit the modern high-quality optics perfectly.
But nevertheless you will get visible better quality with a better lens even on a low-resolution film (see below).
I get the concept of total resolution (i.e. 150lp/mm lens with 100lp/mm film gives you less than 100lp/mm), it's a nuance but doesn't change much. I hope this makes sense.
Well the calculation of "system resolution" is more a rule of thumb than a totally precise calculation method "down to 1 lp/mm", but it works quite well:
1/system resolution = 1/lens resolution + 1/film resolution.
So you will benefit from a better lens even when a low resolution film is used - and vice versa.
The recent modern 35mm lenses are so good that most of them are only diffraction limited from about f2.8 on. The diffraction limit of white light at f4 is 400 lp/mm, and about 250 lp/mm at f5.6.
Zeiss achieved 400 lp/mm resolution with their ZM Biogon 2.8/25, on the SPUR Orthopan UR film (which is identical to ADOX CMS 20, the first version).
I have achieved about 240-260 lp/mm at f5.6 with several lenses on ADOX CMS 20 II.
Best regards,
Henning