Need Help With DOF

Stu Engelman

Hello Everyone,

I'm hoping someone can help me with what is likely a fairly typical problem. My apologies if what I am asking for cannot be done, but I thought I'd see if anyone has any insights on my question.

I am shooting mostly landscapes with my Olympus Evolt E-500 camera and a variety of kit level normal/telephoto zoom lenses. Things are going very well, with the one exception that I can't seem to find any intelligent way to manage DOF. My typical process is to focus manually, set ISO at 100, set aperture judgmentally to obtain decent DOF (narrower for shots with close foreground in composition), and finally meter the shutter speed as the balancing item. If the shutter speed comes out slower than 1/60 second, I'll open up the iris to speed the former up (to avoid chromatic blotching).

The above process works well about 90% of the time. In about 10% of my shots, part of the image is out of focus due to the aperture being too wide. I've attempted to refine the process using the camera's DOF preview, but the display is too dark to be useful in any practical way (impossible to reliably determine where focus is falling off).

My "ideal scientific" process would be something like the following:

(1) Compose picture
(2) "Somehow" determine near/far distance lengths in composition
(3) "Somehow" determine correct focus point (would be about 1/3 deep into focal range) and set focus on that point
(4) Set ISO to 100
(5) Use lens manufacturer DOF chart to set aperture based on focal length being used for zoom and near/far distances in (2)
(6) Use camera meter to compute shutter speed
(7) Shoot picture

The problem in the above is: how do I accomplish (2) and (3) without getting a very expensive long distance range finder (I'm referring here to the kind surveyors use, not the typical mini-range finders golfers use to figure out what club to use)? Is there some way to implement the spirit of the scientific approach alluded to above, without going too crazy on the spending side?

Thanks, Stu Engelman

Lovesong

While I'm not familiar with the E-500 (though my father owns one), on most dSLRs there is the so-called DOF preview button. On my 5D it's on the left thumb (close to the lens mount), while on the 70D I often use at work it's on the right middle finger. Basically what that button does is it stops your lens down, and you get an idea of what the DOF will be (hence the name). This may be a bit harder to do on a 4/3 mount, due to the fact that when you stop you also get less light to the viewfinder, and the smaller viewfinder might not give you a good idea of what your DOF is.

My advice for shooting landscapes, especially when you want everything to be in focus, is shoot at either f/8 or f/11, and if that produces shutter speeds that are slower than what you want, you might want to get a tripod, and either a remote shutter or turn the camera on the timer to prevent shake. Good luck.

Stu Engelman

Lovesong wrote:

While I'm not familiar with the E-500 (though my father owns one), on most dSLRs there is the so-called DOF preview button. On my 5D it's on the left thumb (close to the lens mount), while on the 70D I often use at work it's on the right middle finger. Basically what that button does is it stops your lens down, and you get an idea of what the DOF will be (hence the name). This may be a bit harder to do on a 4/3 mount, due to the fact that when you stop you also get less light to the viewfinder, and the smaller viewfinder might not give you a good idea of what your DOF is.

My advice for shooting landscapes, especially when you want everything to be in focus, is shoot at either f/8 or f/11, and if that produces shutter speeds that are slower than what you want, you might want to get a tripod, and either a remote shutter or turn the camera on the timer to prevent shake. Good luck.

Hi,

Thanks for your reply. The E-500 most certainly does have a DOF preview, but most of the time it's so dark I can't reliably determine exactly where, or even if, DOF is falling off.

I already use a tripod, and set a shutter and mirror reflex delay, to minimize camera shake. My main problem is sunrise/sunset shots. The low ambiant light does not permit "winging it" with the aperture. At these times, I really need to determine the most efficient aperture (widest iris that keeps the composition fully in focus) so shutter speed can be maximized to avoid chroma noise.

Thanks again,

Stu

wfeller

Sounds like a hunting rangefinder may be a possible partial solution. "Too crazy" is subjective.

???
http://www.opticsplanet.net/hunting-range-finders.html

Stu Engelman

wfeller wrote:

Sounds like a hunting rangefinder may be a possible partial solution. "Too crazy" is subjective.

???
http://www.opticsplanet.net/hunting-range-finders.html

Hi,

Thanks for your response.

I took a look at your link, and it appears hunting rangefinders are only useful up to about 1000 yards, not much more than golfer's rangefinders (about 700 yards). I was able to find some high end portable rangefinders that work up to about 1300 yards (these cost about $2,500), but even these would not be effective for landscape photography. Since "inifinity" would constitute the distance to the horizon for photography purposes, my guess is that something on the order of five miles is needed.

I'm wondering whether any cameras have multi-point rangefinding capability built in (something like the technology in http://www.mdl.co.uk/laser_systems/laserace-scanner/index.html). This would permit the camera to automatically determine the near/far focal distances, compute the focal point (one-third into the focal range), and then set the aperture automatically in shutter priority mode (the aperture would be a balancing item to adhere to the metered exposure given the aforementioned distances and the selected focal length). In fact, this process seems so obvious, I don't know why it isn't commonly offered. Maybe it would be too expensive to manufacture for the mass market.

Stu

wfeller

Stu Engelman wrote:

Hi,

Thanks for your response.

I took a look at your link, and it appears hunting rangefinders are only useful up to about 1000 yards, not much more than golfer's rangefinders (about 700 yards). I was able to find some high end portable rangefinders that work up to about 1300 yards (these cost about $2,500), but even these would not be effective for landscape photography. Since "inifinity" would constitute the distance to the horizon for photography purposes, my guess is that something on the order of five miles is needed.

I'm wondering whether any cameras have multi-point rangefinding capability built in (something like the technology in http://www.mdl.co.uk/laser_systems/laserace-scanner/index.html). This would permit the camera to automatically determine the near/far focal distances, compute the focal point (one-third into the focal range), and then set the aperture automatically in shutter priority mode (the aperture would be a balancing item to adhere to the metered exposure given the aforementioned distances and the selected focal length). In fact, this process seems so obvious, I don't know why it isn't commonly offered. Maybe it would be too expensive to manufacture for the mass market.

Stu

You said it, now it's going to happen. But I've thinking about the problem I've been having with the wind wreaking havoc on me personally (because nobody in the world seems to produce photos with blur like I get). Without the equational aspects, our problems sound somewhat similar. Using the eye, I'm thinking a tilt-shift lense as a possible solution.

Here's a starting point:
http://www.hartblei.eu/en/products.htm

If I do it I'll probably run with whatever Nikon has in mind, but I'd like to save that for looking at last.

Stu Engelman

wfeller wrote:

You said it, now it's going to happen. But I've thinking about the problem I've been having with the wind wreaking havoc on me personally (because nobody in the world seems to produce photos with blur like I get). Without the equational aspects, our problems sound somewhat similar. Using the eye, I'm thinking a tilt-shift lense as a possible solution.

Here's a starting point:
http://www.hartblei.eu/en/products.htm

If I do it I'll probably run with whatever Nikon has in mind, but I'd like to save that for looking at last.

Hello,

I took a look at http://www.hartblei.eu. This is an excellent reference, and gets at my problem exactly. The Hartblei shift/tilt lenses offer almost unlimited DOF, even with wide apertures, as long as the focal plane rotation angle is set accurately. Hartblei in essence is saying the same thing I am: implementing correct DOF, using the standard fare in available camera hardware, is nothing more than a crapshoot. Although Hartblei does not make shift/tilt lenses for the Olympus Four/Thirds camera system line, the spirit of what they are accomplishing for other camera systems (Nikon, Canon, etc.) definitely gets at the heart of my issue.

Historically, I don't believe my issue has ever been sufficiently addressed, perhaps with the exception of the Hartblei technology you just introduced me to. In the days of film cameras and prime lenses, you could compute proper apertures using the "DOF scale" on the lens: just line up the near/far distances on the distance ring with the iris marks on the aperture ring, and voila, you get both the proper aperture and correct focal distance. Nice in theory, but it doesn't really work unless you have a rangefinder to obtain the inputs (near/far distances) and calibrate the output (focal distance). And without spending gobs of money, you can't perform rangefinding today beyond about 1000 yards. The preceding solution, wholly inadequate to the task, can't even be attempted today, as zoom lenses cannot employ DOF scales (since the scale needs to change with each zoom position).

I think my concept of multi-point in camera rangefinding with auto-aperture setting may be practical, as long as "surveyor-quality" readings are not required (so cost can be held down to acceptable levels). In the meantime, your focus on tilt/shift lenses is right on point, and lends strong support for the relevence of this issue.

Thanks again for an excellent reference and a real eye-opener.

Best regards, Stu

ian408

Is it just me or are you spending too many cycles on this?

I would suggest that rather than adjust aperture, you adjust ISO. That should take care of the problem and
allow you to maintain your desired aperture and shutter speed.

Ian

Stu Engelman

ian408 wrote:

Is it just me or are you spending too many cycles on this?

I would suggest that rather than adjust aperture, you adjust ISO. That should take care of the problem and
allow you to maintain your desired aperture and shutter speed.

Ian

Adjusting ISO is exactly what I'm trying to avoid. Going much above 150 adds alot of luminance dots to my images. Thus my desire to find an efficient way to set aperture, i.e., so range in focus just overlaps composition, but goes no further. This will permit the maximum possible shutter speed, minimizing chroma noise.

Miguel Delinquento

Stu Engelman wrote:

Adjusting ISO is exactly what I'm trying to avoid. Going much above 150 adds alot of luminance dots to my images. [deleted]

I'm not very familiar with the Olympus Evolt. Is the added noise a personal aesthetic issue or is it more objective? I ask because ISO 150 seems pretty slow. I tend to shoot landscapes at ISO 200-400 and can live with some results up to ISO 800.
Photoshop plugins or Lightroom deal with noise pretty well.

Stu Engelman

Miguel Delinquento wrote:

I'm not very familiar with the Olympus Evolt. Is the added noise a personal aesthetic issue or is it more objective? I ask because ISO 150 seems pretty slow. I tend to shoot landscapes at ISO 200-400 and can live with some results up to ISO 800.
Photoshop plugins or Lightroom deal with noise pretty well.

Hi Miguel,

Unfortunately, the Olympus Evolt-500 does not handle ISO noise or chromatic noise very well. The only way to limit these artifacts acceptably with this camera is to keep ISO under 200 and shutter speed faster than 1/60 second. Thus the need to be very efficient in setting aperture for the frame contents (just narrow enough, but no narrower) when light is low (sunrise/sunset, when I like to shoot).

I've had poor results trying to post-process the noise out, especially luminance dots from high ISO's. The luminance noise filter PS provides is essentially a blurring algorithm, and no amount of sharpening can restore detail lost in the process that was not actual noise to begin with.

Thanks, Stu

Miguel Delinquento

I feel for you
Thanks for filling me in, Stu.
That sounds like a pretty significant constraint on one's shooting. Its not like these issues will magically disappear. Nothing against Olympus (some of my best friends, er, cameras are Olympus) but have you considered a do-over? Besides your sunken costs, why are you staying with this particular tool?

ian408

One thing you might consider is a tool like Noise Ninja to help clean up the noise from higher ISO's.

Stu Engelman

Miguel Delinquento wrote:

Thanks for filling me in, Stu.
That sounds like a pretty significant constraint on one's shooting. Its not like these issues will magically disappear. Nothing against Olympus (some of my best friends, er, cameras are Olympus) but have you considered a do-over? Besides your sunken costs, why are you staying with this particular tool?

Hi Miguel,

I really like the Olympus system. Although it does not handle noise as well as I would like, my standards in this regard are very high and it may be bothering me more than others would notice (i.e., I may have the same issues with other camera systems). Also, the Olympus system handles diffraction and chromatic shift extremely well (almost impossible to generate any).

Stu

Stu Engelman

ian408 wrote:

One thing you might consider is a tool like Noise Ninja to help clean up the noise from higher ISO's.

Hi Ian,

Thanks for this advice. I've heard an awful lot of magazine article authors rave about this. Apparently, many feel that it does a better job than PS with luminance noise. This might be a good solution - go to higher ISO's to enable faster shutter speeds, and then clean up in Noise Ninja.

Thanks for the good advice, Stu

Stu Engelman

ian408 wrote:

One thing you might consider is a tool like Noise Ninja to help clean up the noise from higher ISO's.

Hi Ian,

I wanted to thank you for your excellent advice. I purchased Noise Ninja, and it's absoultely incredible. It lets me remove both ISO and sensor heat noise very intelligently (i.e., without destorying image detail the way native PS filters do). This in turn lets me use higher ISO's and lower shutter speeds, allowing for the smaller apertures I need to avert DOF problems. Thus, I can now shoot sunsets without DOF falloff in the foreground, which was my main problem.

Thanks again for the great recommendation, Stu