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RodinalDuchamp
31-Jan-2015, 11:44
I have been struggling to get my landscape shots in complete focus from fore to infinity.

I have tried focusing at hyperfocal distance. Which for my lens (90mm) is 12.08 feet at f 22.

However this has yielded less than adequate results.

When measuring the 12.08' distance. Does one measure from the film plane, from the front of the lens, or the rear of the lens?

How does one accurately measure for this technique for optimal results?

Jac@stafford.net
31-Jan-2015, 12:26
I have been struggling to get my landscape shots in complete focus from fore to infinity.

Can't be perfect. There is only one sharp area - where the lens is focused. The rest is a matter of degree out-of-focus. Movements can help a lot, but you haven't asked about that.

When measuring the 12.08' distance. Does one measure from the film plane, from the front of the lens, or the rear of the lens?

Usually closer to the center of the lens. :)

For practical purposes the place to measure is from the aperture diaphragm, unless the source of your DOF table specifies otherwise. Strictly speaking the measure is from entrance pupil, but the difference in a nominal-normal or modest wide lens like yours is insignificant for DOF measurements.

cyrus
31-Jan-2015, 12:48
I have tried focusing at hyperfocal distance. Which for my lens (90mm) is 12.08 feet at f 22.

However this has yielded less than adequate results.

People tend to believe these online calculators with their tenths or hundredths of a decimal place precision a little too much. There is such a thing as false precision.

Hyperfocal distance focusing will not give you perfectly sharp backgrounds as your foreground. It will only result in "close as possible" results, setting aside the other inherent limitations of lenses and haze/diffraction etc. What you're counting on when using hyperfocal focusing is that the blurriness of the background that results from this, is within the "normal" existing level of blurriness of the photo, so viewers can't detect it...as much.

Mathematics: For a lens focused at infinity, the smallest object that can be resolved effectively has the same size as the focal length divided by the aperture of the lens. Once you focus closer, that equation changes inevitably, and things become harder to resolve..

The general rule for scenic photographs, where one wishes to maximize the depth of field, is as follows. Set the focus at the distance of the most distant object. Then set the lens opening to the size of the smallest object to be resolved in the foreground. No calculations needed!

http://www.trenholm.org/hmmerk/DOFR.html

Frankly, this effort to create pin-sharp backgrounds in landscape photography bugs me a little. We humans evolved to perceive depth, partly by the level of bluriness of things. It looks sort of HDR-ish when everything, from a rock nearby to a distant mountain peak, is pin-sharp.

RodinalDuchamp
31-Jan-2015, 13:53
People tend to believe these online calculators with their tenths or hundredths of a decimal place precision a little too much. There is such a thing as false precision.

Hyperfocal distance focusing will not give you perfectly sharp backgrounds as your foreground. It will only result in "close as possible" results, setting aside the other inherent limitations of lenses and haze/diffraction etc. What you're counting on when using hyperfocal focusing is that the blurriness of the background that results from this, is within the "normal" existing level of blurriness of the photo, so viewers can't detect it...as much.

Mathematics: For a lens focused at infinity, the smallest object that can be resolved effectively has the same size as the focal length divided by the aperture of the lens. Once you focus closer, that equation changes inevitably, and things become harder to resolve..

The general rule for scenic photographs, where one wishes to maximize the depth of field, is as follows. Set the focus at the distance of the most distant object. Then set the lens opening to the size of the smallest object to be resolved in the foreground. No calculations needed!

http://www.trenholm.org/hmmerk/DOFR.html

Frankly, this effort to create pin-sharp backgrounds in landscape photography bugs me a little. We humans evolved to perceive depth, partly by the level of bluriness of things. It looks sort of HDR-ish when everything, from a rock nearby to a distant mountain peak, is pin-sharp.
This is a very interesting article. I'll have to sit and read thoroughly.

Peter De Smidt
31-Jan-2015, 14:56
Note that hyperfocal distances depend on an allowable circle of confusion. With my Nikons and medium format, the lens markings can be used for hyperfocal determination. So, if I use F/8, and I place the far mark on infinity, then the other f/8 tick will correspond to the closest element in the scene that should be sharp...for a really small print. Leave the lens focused where it is, and stop down two more stops, i.e. to f/16. In effect, this would be accepting a much smaller blur as acceptable.

If you don't care about infinity, focus on the near, take a distance reading, focus on the far, take a reading. Set the lens in the middle of that spread. Read the f/stop that encompasses that distance spread, say f/8. Stop down two more stops. Take the picture.

With LF, I use the distance changed between the standard. There's an article about this on the LF homepage. It'll list ideal and acceptable spreads for various apertures. You can use a measuring tape or a ruler to measure the spread. I put an adhesive scale, one used for wood working equipment, on my camera.

Dan Fromm
31-Jan-2015, 15:03
I have tried focusing at hyperfocal distance. Which for my lens (90mm) is 12.08 feet at f 22.

However this has yielded less than adequate results.

When measuring the 12.08' distance. Does one measure from the film plane, from the front of the lens, or the rear of the lens?

How does one accurately measure for this technique for optimal results?

With a 90 mm lens where you measure from makes very little difference.

You haven't told us all. Which DoF calculator did you use and what did you tell it?

I just checked my own DoF calculator. It says that a 90 mm lens @ f/22 focused to 12 feet will give acceptable sharpness from around 1.1 m to around 151 m, with a .1 mm CoC. This isn't the Dofmaster (http://www.dofmaster.com/dofjs.html) result of 6' to 3242' but Dofmaster and my calculator agree that with your setup DoF won't reach infinity. And the CoC of .1 mm that Dofmaster uses for 4x5 is much too large. It is good for contact printing at best. Smaller CoC, less DoF.

RodinalDuchamp
31-Jan-2015, 15:26
I used the scheider calculator on their website.

Dan Fromm
31-Jan-2015, 15:46
That's not a calculator, that's a table. And you misread it. See https://www.schneideroptics.com/info/depth_of_field_tables/4x5/90depth.htm and try again.

RodinalDuchamp
31-Jan-2015, 15:57
That's not a calculator, that's a table. And you misread it. See https://www.schneideroptics.com/info/depth_of_field_tables/4x5/90depth.htm and try again.
Dan I used this which they call a calculator: https://www.schneideroptics.com/software/DOF_Calculator.xls

However on the table you posted the hyperfocal length at f22 was listed at the bottom as 12.08. Maybe I am reading the table wrong, would you be able to help me find my error?

I also see that focusing to infinity has its merits at f32

But that brings me back to how does one determine focus, from film plane or diaphragm, or a different point.

Jac@stafford.net
31-Jan-2015, 17:26
But that brings me back to how does one determine focus, from film plane or diaphragm, or a different point.

At some point you have to employ experience. Photography is not a lab experience.
.

Dan Fromm
31-Jan-2015, 17:44
Thanks for giving a link to the spreadsheet. I set the focal length to 90 mm, used blur circle = .1 mm, looked in the f/22 column. Hyperfocal distance is 12.08' as you reported. I set that in one of the focused distances, got near and far limits of DoF as 6.99 and 44.30 feet respectively for that focused distance. Spreadsheets are handy that way, one plugs numbers into the right cells and others recalculate to conform.

Schneider uses a blur circle, conventionally called Circle of Confusion, of 0.100 mm for 4x5. This will barely allow contact printing, won't allow enlargement. Remember that the amount of blur that can be tolerated in the negative depends on how much it is to be enlarged.

Do you have any books on LF photography or optics? If not, you'd do well to get at least one good book on LF photography and study them. You'll learn more from any of them than by asking questions here. The two that are most recommended here are Steve Simmons' Understanding the View Camera and Leslie Strobel's View Camera Technique. Both are available through sellers who list their wares on, in alphabetical order, abebooks.com, alibris.com, amazon.com, ... at very reasonable prices. Interestingly, the French LF forum recommends Jim Graves' A user's guide to the view camera.

I'm not sure which book on optics offers a good combination of price and usability. You might want to look for Arthur Cox' Photographic Optics. Rudolf Kinglake's A History of the Photographic Lens is sometimes touted here but the last time I looked it was hors prix. His Lenses in Photography might be helpful and less expensive.

RodinalDuchamp
31-Jan-2015, 20:25
I own a copy of Ansel's three books but I will try to get my hands on your recommendations. Thank you.

BetterSense
31-Jan-2015, 21:15
This is a very interesting article. I'll have to sit and read thoroughly.

It truly is a revelation, and once it sinks in, you will find yourself looking into the front of your lens instead of the aperture scale, particularly when changing between formats. In one studio setup, I know I need to use an aperture of about 4mm when I want sharp portraits; format is irrelevant... THEN I look at the aperture scale on whatever camera I am using to see how much light is needed.

Peter De Smidt
31-Jan-2015, 22:22

http://www.largeformatphotography.info/fstop.html
http://www.largeformatphotography.info/how-to-focus.html
http://www.largeformatphotography.info/articles/IntroToDoF.pdf
http://www.largeformatphotography.info/articles/DoFinDepth.pdf

RodinalDuchamp
31-Jan-2015, 22:27

http://www.largeformatphotography.info/fstop.html
http://www.largeformatphotography.info/how-to-focus.html
http://www.largeformatphotography.info/articles/IntroToDoF.pdf
http://www.largeformatphotography.info/articles/DoFinDepth.pdf
Will surely. Thank you for taking the time to link those.

Edit: I bet my algebra professor is laughing at me now.

cyrus
2-Feb-2015, 11:54
Hyperfocal focusing is not exact enough for it to make any real difference if you measure from the lens or the film plane etc

Jim Jones
2-Feb-2015, 12:23
Technicians have formulae for DOF. Photographers also have to consider their subjects and how the image will be presented. The dreamy nudes of Anne Brigman certainly didn't demand meticulous attention to DOF. In some of Edward Weston's macro-photographs, an extremely small aperture masked the limits of any calculated DOF. We have to balance science with art.

RodinalDuchamp
2-Feb-2015, 12:25
I've solved my issues by just stopping down to f32.

Heroique
2-Feb-2015, 12:34
We have to balance science with art.

Worthy of printing and taping to the camera or meter...

But just to play devil's advocate, if one in the field insists on determining DOF, precisely and accurately, down to the nearest decimeter – let alone centimeter or millimeter – how much art is it going to take to "balance" this?

I've solved my issues by just stopping down to f32.

I applaud this K.I.S.S. approach, but just be sure that f/32 doesn't become an auto-pilot switch. :cool:

RodinalDuchamp
2-Feb-2015, 13:17
Well for this particular subject matter f32 is necessary for my artistic vision. I don't like the idea of 8-17 minute exposures though so that's a tradeoff In will need to see if I can live with.

Peter De Smidt
2-Feb-2015, 14:32
Faster Film, film with better reciprocity, development choice, and pre-exposure could help. TMY-2 with a Xtol 1+1 gives me a true EI of 500, for example.

RodinalDuchamp
2-Feb-2015, 14:59
Peter I think you recommended Acros 100. I have some more TMY-2 on order from BandH but as soon as I receive it I think I am going to send it back for some Acros. I need to read up on how well Acros works with Rodinal 1:200.

StoneNYC
2-Feb-2015, 15:04
Peter I think you recommended Acros 100. I have some more TMY-2 on order from BandH but as soon as I receive it I think I am going to send it back for some Acros. I need to read up on how well Acros works with Rodinal 1:200.

TMY-2 and Acros100 are essentially equal in speed/reciprocity, give or take how you choose to expose, even though TMY-2 needs an immediate 1/2 speed correction after 1 second, it's also 2 speeds faster to begin with, so essentially it's technically faster at first than Acros100, but then it catches up later.

Both are excellent but I do prefer Acros100 for long exposures, but that's a personal choice and look preference.

RodinalDuchamp
2-Feb-2015, 16:30
Stone I usually rate TMY-2 @ 100. My exposure assistant app however shows Across as being MUCH faster at 240 seconds for metered exposure. 5:39 for Acros after corrections, 17:54 for TMY-2 but Howard Bond's tests state only about 480seconds 9 minutes.

I was skeptical as you k ow of TMY-2 as we've discussed in another thread but now after using it I am happy I went with it. With stand development and 1:200 rodinal I can really control the highlights in a way that I didn't know I could. Though this probably just the developer doing what it's meant to do TMY-2 has a beautiful tonality that allows for good separation in those halo-like highlights. I have seen some really nice Acros stuff online but not in person so I'll have to try it and see what happens. I dont want to become too attached to TMY-2 as it was hard enough to break away from just shooting Tri-x.

StoneNYC
2-Feb-2015, 16:48
Stone I usually rate TMY-2 @ 100. My exposure assistant app however shows Across as being MUCH faster at 240 seconds for metered exposure. 5:39 for Acros after corrections, 17:54 for TMY-2 but Howard Bond's tests state only about 480seconds 9 minutes.

I was skeptical as you k ow of TMY-2 as we've discussed in another thread but now after using it I am happy I went with it. With stand development and 1:200 rodinal I can really control the highlights in a way that I didn't know I could. Though this probably just the developer doing what it's meant to do TMY-2 has a beautiful tonality that allows for good separation in those halo-like highlights. I have seen some really nice Acros stuff online but not in person so I'll have to try it and see what happens. I dont want to become too attached to TMY-2 as it was hard enough to break away from just shooting Tri-x.

TMY-2 at 100? Wow! Ok, hey everyone has a method, I like that Acros100 seems to rate perfectly at 100, TMY-2 can be done at 400 or 320 for me, just depends. But Acros100.

RodinalDuchamp
2-Feb-2015, 17:34
Yes I'm a big puller. It just WORKS with rodinal... Lol would be funny to see a boom in this rating. My secret sauce.

ic-racer
5-Feb-2015, 11:08
I'd recommend not blindly using the 'hyperfocal' technique in view camera (or any) photography.

For more in depth reasoning why, check this PDF. To get right to the point, compare pages 23 with 30. http://www.trenholm.org/hmmerk/TIAOOFe.pdf

In my own 'landscape' work, trees and stuff in the distance are rendered very small on the resulting print. I want these things to have great clarity to aid in recognition (ie so they are not blobs). As objects get closer to the camera, they are bigger and can therefore tolerate progressively greater degrees of blurryness without affecting the viewer's comprehension of the subject matter. It so happens that infinity focus satisfies the above conditions.

RodinalDuchamp
6-Feb-2015, 14:46
I'd recommend not blindly using the 'hyperfocal' technique in view camera (or any) photography.

For more in depth reasoning why, check this PDF. To get right to the point, compare pages 23 with 30. http://www.trenholm.org/hmmerk/TIAOOFe.pdf

In my own 'landscape' work, trees and stuff in the distance are rendered very small on the resulting print. I want these things to have great clarity to aid in recognition (ie so they are not blobs). As objects get closer to the camera, they are bigger and can therefore tolerate progressively greater degrees of blurryness without affecting the viewer's comprehension of the subject matter. It so happens that infinity focus satisfies the above conditions.
I have been experimenting with several techniques and infinity focus combined with stopping down further to about f32 has provided very pleasant results for what I am trying to achieve.

My target print size is 16x20. When I print we shall see if diffraction is causing some issues at this aperture.

Peter De Smidt
6-Feb-2015, 15:05
F/32 shouldn't be a problem diffraction wise at that enlargement size.

RodinalDuchamp
6-Feb-2015, 15:11
Great. I would try to go larger but I dont have the facilities.