Resolution Comparison Between Films?

[ClickCL]

Hi, I'm curious if anyone has a resource or personal opinion on the resolution differences between films? I have very little experience with LF but have a decent amount of experience shooting other formats up to LF.

I have noticed that generally E-6 films seem to have an edge over C-41 films, but with that said, there are so many variables it's hard to confirm if what I am seeing is reality. I would be very interested to see a side by side test done or hear some of your experiences. Also, where do you think silver gelatin stands against the two. Obviously we would be comparing like film speeds and more specifically the fine grain, slower films.

I have a project I'm preparing for and I'm trying to determine which film I want to work with. I can only imagine, if film resolution is noticeable on my smaller formats, then on the scale of an 8x10 it would make a significant difference, no? Thank you in advanced for your help.


EDIT: I realize now, I should have posted this in the Darkroom: Film, Processing & Printing category. If there is a way to move or delete this thread, that would be great. Thanks

No problem, thread moved. --Oren

[interneg]

C-41 films outperform E-6 on the metrics that matter - sharpness, latitude, granularity etc - and if your display medium is anything other than the original transparency, these factors matter very strongly indeed.

[ClickCL]

Interesting! I was well aware that C-41 has a greater latitude but I did not expect granularity or sharpness to be a strength over e-6. At the very least, if they are comparable, then there is little use in choosing one over the other based on the merits or "resolution".

My display medium will be a transparency, however I was still considering the use of a c-41 film. Thank you for your reply; I appreciate it.

[Drew Wiley]

Don't accept any generic answer. It all depends of the specifics. You are correct in assuming that there are many variables. Technically, you're not dealing with granularity, but with the nature of dye clouds. Because positive film tends to have higher contrast, detail edges often do look sharper. Greater color saturation also lends that impression. But there are ways to juggle all of that. Grain per se is rarely an issue with large format color printing. And perceptible detail is more related to the degree of enlargement, control of focus, and enlarging skills. I've printed from both chrome and color neg sheet film, and even lifetime pro lab owners couldn't tell which was which. But a lot of work can go into a quality print, regardless. I won't address pros or cons scanning negs vs chromes, because I don't print anything digitally, just optically, which eliminates those particular variables. But it might take many projects to truly get ahold of all this. There's a learning curve. Don't overthink it. Start with whatever kind of film you are most comfortable with.

[ClickCL]

That makes perfect sense. Honestly, I think what I took away from interneg's response landed me with the same conclusion you have suggested. It seems that any edge one film type/process has, is not significant enough to make any appreciable difference in light of the many variables that exists. Thank you for the additional insight and knowledge.

[Sasquatchian]

Look at Kodak's own data for RMS Granularity and their data for resolving power. That will tell you that in most cases ISO 100 E-6 emulsions are both finer grained and sharper than C-41 emulsions. You can shoot your own comparison tests and look at the actual film through a low power microscope. You will immediately see the difference. Or, you can buy yourself a drum scanner like I did twenty-two years ago and scan thousands of pieces of all kinds of films and see for yourself. C-41 emulsions generally, but not always have dynamic range advantages and more importantly, the ability to be shot under varying lighting and still deliver exceptional results - for instance, even though it's not recommended, you really can shoot daylight balanced C-41 under tungsten and scan it perfectly or print it if that's your choice. What you see first hand with the drum scanner is that you can scan E-6 at any hardware resolution up to 8000 ppi and use the corresponding auto aperture setting in the scanner, which would mean 3.17 microns for that 8000 ppi call, but through careful testing of many different C-41 films, in order to not have overly grainy scans, you need to match the scanner aperture to the grain size, more or less, of the film, which usually means using the 16 micron aperture, which effectively limits the hardware resolution to 1600 ppi or using the 12.7 micron aperture which yields 2000 ppi. Using the hardware corresponding aperture of 6.35 microns for 4000 ppi or the aforementioned 3.17 microns for 8000 does not yield any additional scan detail, only greatly enhanced, if you want to call it that, grain structure.

Back in May of 2003 I had a photographer from Memphis fly out to California and we made some test scans from his 4x5 Portra film. We did test scans at multiple apertures, and he did the same at a couple other places in Southern California, me using the Howtek 8000, someone using a Hell Chromagraph 3300 (I think) and another using the 8000 ppi ICG scanner. He went home and made comparison prints from all as well as traditional analog projected prints and came to the conclusion that the Howtek made the best scans overall but that the scans at 16 micron were a very close match to projected prints for both sharpness and grain, that the 12.7 micron scans gained a tiny bit of detail but at the expense of increased visible grain and that the 19 micron scans had even less grain but slightly less detail.

The one C-41 film that can hold up to the higher scan resolutions is, of course, the recent Kodak Ektar emulsions, but they also have a look to them that you have to learn to love, and I don't love them. I shoot C-41 Portra for its look and know that when I shoot it that, yes, I'm giving up some ultimate detail but getting dynamic range in return. Toward the end of the film era for shooting commercial job, which was in the very early 2000's I had completely switched over to Portra for shooting architectural jobs. Clients didn't care one way of the other as all they cared about was the final image and didn't know from differences in emulsions, but it was also because I had spent a few years learning how to drum scan color negs when the common thought at most scanning houses was that it couldn't be done. It was just because none or them understood the problems involved. But after 2004 or so there was no reason at all to shoot film for that type of commercial work and it's even more so today. Fine art is one thing but for something like my first and last job of this year - a big architectural job, the results from a 5DSR and a suite of tilt-shift lenses is far better than anything we used to get shooting 4x5 film.

But, jeez, do your own tests and see for yourself. It's not that hard and then you'll know what's right for you and not have to rely on people like me who have spent nearly a quarter century comparing this shit.

[m00dawg]

I have a project I'm preparing for and I'm trying to determine which film I want to work with. I can only imagine, if film resolution is noticeable on my smaller formats, then on the scale of an 8x10 it would make a significant difference, no? Thank you in advanced for your help.

This depends on how large a print or scan you plan on making. I just printed an 11x14 shot on Porta 160 in 35mm and it looks great! Can I see the grain? Yes! Does it matter? Well, yes! I think it makes it look quite nice! Then I have a 30x24 print hanging above my fish tank taken on Provia 100 in 4x5 which I had drum scanned. The detail is stunning but at the distances I typically view the print, the detail isn't necessary.

I guess to take a step back - "pixel peeping" is a dark art when it comes to film photography and you loose a lot of other important qualities if you're just looking for ultimate resolution, especially if you're already in 8x10 territory. Velvia 50 approaches a gigapixel in resolution (Ben Horne has a video where he had one of his images drum scanned at the highest resolution he could and it was something around 900+ mp). If you wanted ultimate resolution, grab some ADOX CMS 20 and maybe use R,G,B filters and make a composite technicolor style solution in post.

Rather, if it were me, I'd find the stock that has the color palette that fits me best and go from there. All the color stocks have nice grain but can different, in some cases considerably, in looks, especially when you include chrome films. To me that will make a far FAR bigger impact on the final product than resolution.

[Drew Wiley]

RMS granularity is valid for comparing related films from the same manufacturer, but it can be a bit misleading if comparing chrome and color neg films, which are different categories. Of course, one can reasonably assume that a slower film like Porta 160 is going to be finer-grained than a fast film like Portra 400. And their advertised claim that Ektar is their finest grained CN film of all is true. But that doesn't mean Velvia 50 is going to have less visible grain because, as a chrome film, it handles that grain differently. But again, in large format work, this is all largely a non-issue, whereas contrast range and specific color palette probably will be an important factor. Forget "pixel peeping". Start printing true optical with fine gear and everything digitally printed starts looking gritty. And yes, people do stick their noses right up to my prints, even 30x40 inch ones. If the detail is there, people will want to take it in. The nonsensical law of "normal viewing distance" is meant to be broken.

[interneg]

Very simply, Hollywood went for neg/ pos processes because it was better qualitatively than pos/ pos processes - there's plenty of hand-waving that goes on about transparency, but most of it comes back to a heck of a lot of scanner operators being pretty bad at inverting and colour balancing negs to the point that they look worse than an equivalent transparency. That shouldn't be the case - I've seen plenty of evidence that even with 1980's materials, VPL did a better job in granularity, sharpness, low contrast detail resolution etc than EPN. And all of those were soundly beaten by Portra and Ektar. And yes, optical prints with current materials in many cases offer aspects of quality and potential for intervention that even the best scanners struggle to deliver.

[Drew Wiley]

Oh, but the hue rendition of color neg films was (past tense) so disappointing for such a long time unless skintones were the priority. And the best motion picture color standard of all was Technicolor - a black and white film process involving tricolor dye transfer, and not color negative film at all. I guess if I had printed much color from medium format or 35mm, I might have gotten nitpicky over this subject, but it gets kinda silly when it comes to the surplus of real estate when using sheet film. Nowadays, I've been shooting MF color a lot more than I once did, due to the high cost of color sheet film. And select color neg films like Ektar indeed hold more detail than former versions did. Taming its cyan idiosyncrasy is a bit more involved, but doable with correct filtration at the time of the shot.