Film flattness issues in MF

[dpurdy]

I am wondering if there is a general concensus about which type MF camera system has the least film flattness issues. Is it the Hasselblad type of rolling the film sort of against the curl? Or is it the TLR way of rolling the film with the curl? Or is it something else or some other factor?

thank you
Dennis Purdy

 

[Curt]

I have had a Mamiya 645 for 30 years and used it with all kinds of films and brands and have never had a film flatness problem with it. I have had a problem with the film loading on reels and curling up in the negative carrier. Not in the camera though. And I too live in the Northwest so that's not an excuse! The only time I hear of 120 film curl is in processing.

 

[dpurdy]

I think the Mamiya rolls the film like the Hasselblad does. It never occured to me that the Northwest was responsible for film flattness issues, but the dampness of my basement certainly helps my fiber prints to lie flat.

 

[luvcameras]

Pentax 67 is known for very flat film holding

Dan

 

[Chazzy]

Koni-Omegas have a pressure plate which backs away from the film as it advances and then presses the film forward for each exposure. It's a very ingenious design.

 

[jimgalli]

The antiquated Mamiya Universal with the Mamiya S shaped holders. No, you won't find any consensus.

 

[David A. Goldfarb]

Film flatness issues are hard to recognize until you try something with better film flatness than you were used to and realize that what you thought was "sharp" wasn't quite "SHARP"--sort of like moving from an open neg carrier to a glass neg carrier.

Linhof Super-Rollex film backs have the best flatness of anything I've used.

 

[keithwms]

My standard check with a rollfilm back is simply to run film through it with the back open so that I can see if there are any issues. You can check whether the film is taut, the pressure plate is acting properly, and check that the back mounts properly.

Over time, I have satisfied myself that my own focusing errors at wide apertures were more likely to cause me issues than the flatness of film in my rollfilm backs. I did discover that one of my really old backs wasn't mounting tightly so I tossed it.

Bottom line: everything matters in photography, the question is how much it matters in practice, relative to other issues. And everybody develops his/her own answer to that. I guess if I were shooting test charts or doing lens testing at wide apertures then I guess I'd use sheet film with a vacuum back!

 

[Bandicoot]

I've never found film flatness a serious problem in rollfilm, but certainly some backs and cameras are better than others in this regard.

I think the quality of the engineering may matter more than whether the back winds with the curl or against it: my least flat (but still perfectly usable) backs are old Graflex ones, and among the flattest are Horseman / Arca ones - both wind in the 'against the curl' way, like a 'blad.

My very flattest-film cameras are 'with the curl' varieties: Rollieflex and, best of all, Fujica rangefinders. The Fujicas are similar to the Pentax 6x7 in the way they wind the film, and the flattness the big Fujicas manage across the whole of a 6x9 frame is extremely impressive.


Peter