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View Full Version : Portra 160 @ f10 vs 400 @ f16 (4x5)



artcorr
7-May-2016, 16:46
Hey guys, my first post here so hopefully I've put this in the correct forum.

I'm shooting something soon and haven't had time to test the lens/film combination, I'm hoping to find out which would produce a better image quality for a big enlargement (~50x62" from 4x5). I'm using a Fujinon SW 90mm f8, and in sunny conditions would like to know if I'd be better off shooting with Portra 160 @ f10 or 400 @ f16. I assume there will be a difference in sharpness but I'm not sure how much and if the difference in sharpness will be lesser or greater than difference in grain. Depth of field isn't really a concern, I'm shooting very top down and can put some tilt on it.

Thanks for any help.

BetterSense
7-May-2016, 17:46
Why not shoot the portra 160 at F/16? Is your subject moving?

artcorr
7-May-2016, 17:53
Sorry I should've mentioned, it's moving water so 1/500 is a must.

Duolab123
7-May-2016, 18:12
Portra is amazing film I've shot a lot of 6x9 Portra 400, 500 f 16 with a Fuji GW 690 camera 90 mm lens, everything is in focus within reason. Sharp as a tack. I'm usually making 11x14s with some cropping, probably 6 or 7 x enlargement. But 6 times four by five inches is only 24 x 30. When enlarging I can't see grain to focus I usually find a straight line. Stuff is amazing.

I think you would still be OK at F8 with Portra 160. No better film ever made for portraits and weddings.
The scanning guru's on this site would know the answer better than me.
I do love Kodak's T grain films!
Best of Luck, Mike

Maris Rusis
8-May-2016, 14:14
Sorry I should've mentioned, it's moving water so 1/500 is a must.
You may have to allow for the shutter not delivering 1/500 second. My shutter speed tester often finds a setting of 1/500 delivers only 1/300 (or slower!) even in a good looking shutter. The problem of leaf shutter efficiency particularly at high speeds and small apertures is a complex subject to study.

Bruce Watson
8-May-2016, 15:25
I assume there will be a difference in sharpness but I'm not sure how much and if the difference in sharpness will be lesser or greater than difference in grain.

Comparing apples to concrete blocks? In my experience, apparent sharpness and apparent graininess are completely different things.

Really, there's a lot of variables here, not least is your personal preferences. The only way you'll answer the questions you have is to set up on a subject, shoot a sheet of 160, then a sheet of 400, develop them, toss 'em on a light table side by side, and loope 'em. If you haven't done it enough to be able to evaluate color negative film on a light table like that, make a small section (say, 11x14 out of your planned monster print) from each negative, put the prints up on your proofing wall side by side under the same light, and judge 'em. Bring people in who have no idea about what you're doing and ask them to choose -- just choose their favorite, no criteria. "Which do you like best?". Out of 10 people, how many choose which print? Then, which print do you like? And there's your answer.

vinny
8-May-2016, 15:49
None of my lenses have an f10 on the aperture scale.
Your lens will be sharper at f16.
Your shutter won't likely give your 1/500 anyway as already mentioned.

Jody_S
8-May-2016, 16:07
You will have a much more even exposure at f16 than f8 or f11. The reason is easy to understand: at 1/500s, a leaf shutter opens it's blades and immediately begins closing them as soon as they reach maximum opening. That means the tips of the leaves do not leave the opening for any amount of time, they are present in the optical path for virtually the entire duration of the (usually 1/250 - 1/300s) interval. That means you may see light falloff from each blade being in the light path more at the edges than at the center. In other words, exposure may be 1/250s at the center, but a jagged 1/1000s at the edges where the tips of the blades finally retract into the shutter. Shooting at f16, however, you may see a center of 1/250s and a more-or-less circular edge of 1/300s.

StoneNYC
8-May-2016, 17:18
Unless you are printing larger than 20x24, there's no reason to worry about sharpness, and even bigger, it's probably fine.

vinny
8-May-2016, 19:54
Unless you are printing larger than 20x24, there's no reason to worry about sharpness, and even bigger, it's probably fine.

???? Please explain
He want to make prints which are 50x62 inches.

StoneNYC
9-May-2016, 03:22
???? Please explain
He want to make prints which are 50x62 inches.

How did I miss that!!!

Thanks Vinny, either way, at the distance people would stand, I don't think it matters much BUT, yes the 160 would be much finer if pressed to the nose. I mean there's a reason I shoot 8x10, and it's not because I like carrying bigger gear ;)

But if you need 1/500th then do what you need to do to get the shot, it won't matter how sharp it is of the shot is blurry because of a slow shutter speed. Use your movements well ;)

Drew Wiley
9-May-2016, 09:53
Different animals. 400 has somewhat higher contrast and saturation than 160. The grain is just slightly larger than 160, but with the significantly faster speed,
it would be the logical choice for moving water. Grain will show regardless at that degree of magnification. Have you tested your shutter speeds? Not many view
camera leaf shutters are accurate at the highest speeds. You might need to consider this. The other question is if your lens will perform decently nearly wide open.
One more reason to choose 400 film.