Large format vs. medium format
I've just started using LF using a Super Symmar 110 XL, so reputedly about as sharp a LF lens as one can get. I use a rock solid tripod, and I believe excellent technique to achieve maximum sharpness.
On a light box and a 10x loup, I'm now looking at the B&W negatives that I've taken with the LF camera, and comparing them with my B&W negatives that I took in medium format (both Hasselblad and Mamiya 7).
Using a 10x loup, the "sharpness" of the medium format negatives seems to literally jump out at me and is much more apparent than it is for the LF negatives.
It's not that the LF negatives are particularly soft or out-of-focus in themselves .... there is good detail there ..... but they seem to be lacking that overwhelming sharpness that I'm seeing in the medium format negatives.
Is this normal?? Am I doing a fair comparison?
Re: Large format vs. medium format
Could be the difference in thickness of the film base. LF film is thicker so the light being transmitted through it is a bit more disperse as you look through your loupe. Smaller negatives are and need to be sharper. Bare in mind that you won't need to enlarge as much for any given print size with the larger negative.
Re: Large format vs. medium format
my fuji/hasselblad negs/lenses are much sharper than any of my lf negs/lenses, it's a fact of life, don't worry, you start to see the difference when you print or scan big.
Re: Large format vs. medium format
What do the prints look like? That's what you should be comparing.
Re: Large format vs. medium format
I think it's a trade-off between optimizing for sharpness or optimizing for enough additional coverage to allow movements. For example, the Digitar lenses don't have the coverage of regular film lenses, and they're sharper.
Re: Large format vs. medium format
From your description, it sounds more a contrast than a resolution issue. You did not state what format you were using, but I assume its 4x5? Did you use a compendium lens shade to shade the lens down to the used area? The 110mm XL just about covers 8x10, so fo 4x5 or even 5x7 that is a lot of non-image light bouncing around in the bellows, whereas the MF lens image circle will be close to the format size. Furthermore, in my experience the 110XL needs f/22 for best performance, it is a little softer at f/16. For f/16 its predecessor, the Super-Symmar HM 120mm is slightly better. Which f/stop did you use?
Re: Large format vs. medium format
A high-resolution lens isn't the whole thing. Also the camera, film-holders etc. must have the same precission. And a heavy camera on a weak tripod doens't help to get sharp negatives.
Re: Large format vs. medium format
It shouldn't be that dramatic a difference, although a 10x loupe is going to reveal a lot. But before condemning large format I would check/test that your film is in the correct film plane (it makes me suspect the ground glass isn't in the right place.)
A quick and easy test is to shoot three sheets of the same scene with a note included in the scene to identfy the piece of film -- one focused to the ground glass, the next a small bit (2mm) focused closer, the next 2mm further... that will tell you everything.
From there it depends on your camera how you go about shimming your ground glass and checking the position of your holders.
Re: Large format vs. medium format
Thanks for the replies so far.
Arne ..... Yes, I wondered if it might be a contrast issue? The B&W negatives on a the LF (I'm using 5x4) look a lot more "flat grey" across the frame compared to what I'd been getting from the MF cameras (or 35mm Leica for that matter). The MF and 35mm negatives have a lot more "punch" / contrast to them.
I don't use a lens shade ..... but most of the images have been taken towards dusk (ie, little natural light), so I don't see that a lens shade would make much of a difference in those circumstances?
Re: aperture. I've used f16 for most of them. Also, f45 for some others. No other apertures used so far.
Re: tripod. I'm using a Gitzo carbon fiber 1348 and an Arca B1 head, so all good weighty stuff. Exposure times have been from 8 seconds --> 30 seconds, typically, with little to no wind.
Re: Large format vs. medium format
Quote:
Originally Posted by
Jon Warwick
Exposure times have been from 8 seconds --> 30 seconds, typically, with little to no wind.
Also little wind during 30 seconds moves the camera, specially the LF-camera with it's big surface.