What's the weaker link for resolution/sharpness?

Excalibur2 · Jun 16, 2009

These days is 200asa 35mm colour film (say Fuji superia) good enough to check a lens out, or what breaks down first the film or image from an excellent lens, when enlarging/scanning a negative.
Which could lead to a topic of:- which is the best colour 200asa film for enlarging/scanning.

EASmithV · Jun 17, 2009

I like cheese!

Excalibur2 · Jun 17, 2009

EASmithV said:
I like cheese!

HuH!......It's not about a film's colours, contrasts or exposure latitude, storing ability and anything else I have missed.........just a plain old neg's ability to enlarge or it's resolution capabilities for an image.
Maybe all 200asa colour films are similar and an excellent lens is better than the film and Ektar at minimum is needed for checking out a lens......someone must know otherwise I'll have to buy some Ektar or FP4, when I've got about 80 rolls of 200asa Fuji superia in the fridge.

Q.G. · Jun 17, 2009

EASmithV said:
I like cheese!

First fried spam. Now cheese... what else is on the menu?

Excalibur2 said:
... otherwise I'll have to buy some Ektar or FP4, when I've got about 80 rolls of 200asa Fuji superia in the fridge.

The wise thing to do is first finish those rolls, then ask the question.

keithwms · Jun 17, 2009

The weakest link is always between the shutter finger and the brain

There aren't too many notable entries in colour 200 speed- let me suggest trying ektar 100 and the kodak and fuji 160 films. But actually superia is suprisingly good and you have absolutely nothing to worry about as you long as you like what you are getting. Good stuff. Be happy.

nworth · Jun 18, 2009

Sharpness is pretty much psychological, and a lot of things are involved. Resolution is an important part of the sharpness issue, but high resolution can still result in the impression of poor sharpness. Contrast and edge effects help give the impression of high sharpness, and the scene itself is a big factor. Some pictures don't need great resolution to quite effective, or even to look sharp. (Certain portraits and scenes with large blocks as the principal subjects come to mind. Things that involve you emotionally, like many photojournalism shots, also cause you to ignore a lot of sharpness issues.) Other things demand high sharpness. In choosing a film, getting one that keeps a high MTF (modulation transfer function) at higher frequencies (line pairs per mm) is more important than just high resolution values in and of themselves. It tells you that contrast, which is important to the impression of sharpness, is maintained in the fine details. You will notice that some films have MTF values that go a little above 100 percent somewhere in the plots. That is evidence of enhanced edge effects, which also contribute to the impression of sharpness.

Excalibur2 · Jun 18, 2009

nworth said:
Sharpness is pretty much psychological, and a lot of things are involved. Resolution is an important part of the sharpness issue, but high resolution can still result in the impression of poor sharpness. Contrast and edge effects help give the impression of high sharpness, and the scene itself is a big factor. Some pictures don't need great resolution to quite effective, or even to look sharp. (Certain portraits and scenes with large blocks as the principal subjects come to mind. Things that involve you emotionally, like many photojournalism shots, also cause you to ignore a lot of sharpness issues.) Other things demand high sharpness. In choosing a film, getting one that keeps a high MTF (modulation transfer function) at higher frequencies (line pairs per mm) is more important than just high resolution values in and of themselves. It tells you that contrast, which is important to the impression of sharpness, is maintained in the fine details. You will notice that some films have MTF values that go a little above 100 percent somewhere in the plots. That is evidence of enhanced edge effects, which also contribute to the impression of sharpness.

Thank you, well I agree with your reply, but people post questions about lenses, and people reply that one lens is sharper than another...and I'm sure anyone here buying a lens would like to know if they have a lemon (or whatever). So the best solution is to have an excellent lab to process the film and produce a 16X20 print of your lenses you own (or have bought) and compare.......erm ok for money no problem guys.
So how do you prove to yourself and produce proof to others which lens is better, in a cheap way...............well I use a good scanner at 4800dpi plus for negs and enlarge in Photoshop, and yes I know I'm viewing results on a computer screen, but finding quite a few lenses (primes and zooms) are giving similar results (after blowing up) and am just wondering are the lenses better than the film (200asa).

Pete H · Jun 18, 2009

Excalibur2 said:
... finding quite a few lenses (primes and zooms) are giving similar results (after blowing up) and am just wondering are the lenses better than the film (200asa).

Perhaps you need a better tripod & mirror lock?

Excalibur2 · Jun 18, 2009

Pete H said:
Perhaps you need a better tripod & mirror lock?

Well of course you are correct in that you should use a tripod for every shot, but would have thought 1/250 or 1/500 sec for a lens under 50mm should avoid camera shake, and maybe 1/500 sec for lenses about 70-200mm is not good enough for my supposedly steady hand (w/o tripod).

Sirius Glass · Jun 18, 2009

Pete H said:
Perhaps you need a better tripod & mirror lock?

And a cable release.

Steve

Sirius Glass · Jun 18, 2009

Excalibur2 said:
Well of course you are correct in that you should use a tripod for every shot, but would have thought 1/250 or 1/500 sec for a lens under 50mm should avoid camera shake, and maybe 1/500 sec for lenses about 70-200mm is not good enough for my supposedly steady hand (w/o tripod).

Some are more steady than others. When there is a thread discussing shooting faster that 1/[focal length] seconds and the mythical Hasselblad mirror bounce there is always someone who claims that they can shoot 2 or 3 or 4 shutter speeds slower with the Blah-blah-X12. Aside from the issue of that they sound apocryphal, not everyone is equally endowed with the same body reflexes and who cares about their claim - most others cannot do that.

The shooting faster that 1/[focal length] seconds works for most people but not all. If this is a problem for someone then they need to use a monopod or tripod.

Steve

StorminMatt · Jun 18, 2009

Focusing can also be an issue. When manually focusing, you might notice that the picture appears in focus over some range of focus distances. And sometimes, it is had to tell EXACTLY where perfect focus lies. This can make some shots turn out soft. Of course, autofocus is not perfect, either. But the decision as to whether to go with manual focus or autofocus should be determined by which is likely to be more accurate for a given individual.

Excalibur2 · Jun 19, 2009

StorminMatt said:
Focusing can also be an issue. When manually focusing, you might notice that the picture appears in focus over some range of focus distances. And sometimes, it is hard to tell EXACTLY where perfect focus lies. This can make some shots turn out soft. Of course, autofocus is not perfect, either. But the decision as to whether to go with manual focus or autofocus should be determined by which is likely to be more accurate for a given individual.

Well if you don't use a brickwall or newspaper, focussing shouldn't be a problem as you would look at a shot for the sharpest part and blow up that.

Makes you think (with reference to sharpness) that with all the things that could go wrong in getting the best out of a lens, a lot of guys are using expensive lenses when cheap would do.
Anyway thanks all, but no one seems to know whether an excellent 35mm lens is limited for it's full potential, using 200asa film.

Q.G. · Jun 19, 2009

It depends on the lens and the film.

Good films resolve (actually, not theoretically) about 100 to 160 lp/mm. The best films did about 200 lp/mm.
A 200 ISO film can be good, can be less good.

What lens?

ajuk · Jun 19, 2009

Is it true that 200 ISO neg film is just 100 film and the labs push it, and if it is could I get a consumer lab to push a film by a stop just by sticking a 200 DX code on it?

Excalibur2 · Jun 19, 2009

Q.G. said:
It depends on the lens and the film.

Good films resolve (actually, not theoretically) about 100 to 160 lp/mm. The best films did about 200 lp/mm.
A 200 ISO film can be good, can be less good.

What lens?

Well it could be my Epson v750 scanner is the weakest link...i.e. 200asa film and good lenses are better than the scanner......
The thread can be summed up:- If you want to check a lens out, then select a slow film colour or B/W, use a heavy tripod, set lens at about f8, choose a subject that can show sharpness, check exposure is correct, have a lab develope and drum scan the neg.....phew

Fredrik Sandstrom · Jun 19, 2009

ajuk said:
Is it true that 200 ISO neg film is just 100 film and the labs push it,

No.

and if it is could I get a consumer lab to push a film by a stop just by sticking a 200 DX code on it?

The lab will not alter the processing based on the DX coding on the cassette. All C-41 film is processed the same regardless of the speed, so the lab is not interested in the film's ISO rating; ISO 100 and ISO 800 film all go together. Only if you ask for a push or pull will they need to process differently.

What's the weaker link for resolution/sharpness?

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