Hyperfocal distance with AF zooms
Can anyone help me with how do I focus the hyperfocal distance with zooms like the
The easiest way to explain what this is ,
The hyperfocal distance is when you have everything sharp from front to end, has to be done manually.
#1. "this is weakest link in zoom use" | In response to Reply # 0Tue 05-Sep-00 11:30 AM
You've discovered the biggest missing feature on zoom lenses, (especially wide angle zooms), If you learned photography with prime lenses that had great depth of field markings for most of the f-stops, it is hard to give that up. A stopped down, hyper-focused lens is faster than any autofocus... but sadly, it will be a bit of a guessing game with the zoom.
The basic theory is that focus is broken into three zones. One zone is in front of the subject, and the other two are behind the plane of focus. The problem for you is to determin the range of those three zones. The first answer is to just close down all of the way. Not all lenses are at their shaprpest at minimum apertures... due to diffraction, so that technique may not give you the best shot. Determin the closest required distance and the farthest... focus a third of the way into the shot. Then while holding your depth of field preview lever, slowly close the aperture until your desired focus is reached. This is not as exact as DOF markings because it uses your vision to judge sharpness... subjective and variable.
To those who choose to laugh at users of older equipment, this is another of those "must have" features that have been done away with in the name of "progress". The knowlege of the use of these features is what use to seperate snap-shooters from photographers... and will keep the used equipment market viable. If you never used it, you won't miss it... but when you have, you can't give it up.
#2. "RE: Hyperfocal distance with AF zooms" | In response to Reply # 0vfnewman Basic MemberTue 05-Sep-00 07:34 PM
I am assuming that in the past you have used depth of field scales to set a lens to its hyperfocal distance. For lenses like those you mention, you need to calculate the hyperfocal distance "manually" for any given focal length and aperture, then set your lens appropriately.
You can find equations for hyperfocal distance and depth of field in any good photography book.
Ask if this isn't clear.
#3. "RE: Hyperfocal distance with AF zooms" | In response to Reply # 2Wed 06-Sep-00 02:40 AM
Al & Victor,
you were spot on how I've learned the "trick" of HFD.
I was hoping that there is something that I have overlooked and there is a trick to do this faster.
I have tried the "one third in..." focusing as well, last when I was shooting a fiels of sunflowers and I had a castle in the far back. I stopped down to f/22 and focused manually with main focus 1/3rd in the field. Still the first 3rd in the shot is not in focus.
DOF preview check I think was done, however I find that very tricky to see since all is so dark.
Any more hints, more than the obvious to go back to my old prime AIS's..?
Thanks for your input,
#4. "more thoughts" | In response to Reply # 3Wed 06-Sep-00 11:17 AM
Thanks for responding to the replies. That is good etiquette... letting the contributors know their effort was worth while.
I can't offer more advise than before, but there is one thing that may help regarding your scenario with the sunflowers. You don't mention the lens, but I would assume you were going pretty wide. The fact that you focused a third of the way into the scene could have been a problem, because different focal lengths have "infinity" occur at different distances. It can be hundreds of feet for a long telephoto, but only 25 feet for a very wide angle lens. Yes the flowers went on forever, but you only needed to cover infinity for that lens. In other words, you probably were almost focused at or near the "infinity" for that lens, and therefore wasted some of your potential near focus. Again, I can't tell you how to know exactly where to focus... and using zooms you have the factor of the "in-between" focal lengths, so only you can make the call as to the actual "convenience" of a zoom that doesn't allow you to control the process fully.
If I were you, I'd do one of the following things, (or both). 1. Get at least one prime lens, A 20 or 24mm lens, and use this at the times that you want the best quality for your "near / far" compositions. Talk about control... you can set the lens in the car on the way to the shoot... one and a half feet to infinity with a 20mm lens. 2. Take a couple of rolls of film, and with your camera on a tripod set the zoom's f-stop to f16, and take pictures of a dense subject, (like your sunflower field), adjusting the focus scale incrementally, while recording the marked distance. Review the film and determine which has the deepest focus that extends to infinity. Check your notes and that will be you "hyperfocal" setting for f16 every time, for example 8 feet. This idea, while doable, will take too much time, since you would have to repeat the process for other aperture settings and focal lengths. In the field, you would have to refer to your notes. You would burn a lot of film to arrive at information that should be readily availible.
I reiterate from my first post, I am not willing to turn over the process of photography to new equipment that assumes that we can't do the basics... and hyperfocusing is a very basic process. If you are doing a group photo, four deep, using those funny little marks will make sure that the guys in the front rows and back rows will be in focus... no guessing, very precise and guaranteed. On a paying job, it has to be that way. No client cares that your new 1200 dollar zoom doesn't have what your 300 dollar prime lens has.
Good Luck, Al
#5. "RE: more thoughts" | In response to Reply # 4Thu 07-Sep-00 03:24 AM
many thanks for all your input. Seems that I got a serious slap in the face when I traded in some of my prime's for the "benefit" of the AF zooms.
Victor, I checked your profile and you have a 20mm AF, can you use HFD with that lens or do I need to look back at AIS lenses.
Both, reason for asking is that the F5's metering system is not working 100% with non-D lenses as known.Also a the AIS versions vs. the AF as 2nd prices tend to be more expensive (I buy all my gear 2nd hand, mainly from http://www.graysofwestminster.co.uk)
Al, any suggestion which wide angle to pick, my previous was the 24mm since the 20 is quite expensive..
Going back to the sunflower experience, when I wanted to get the castle in the frame and not too far, it was up on a hill in the distance( this was down in Tuscany, Italy, would recommend it, if you like your lanscapes with punchy colours and Velvia/E100VS)I used the 80-200 so looking at the distance barrel it should have been (give or take) approx 1/3rd in. Does this make any sense?
So looking back I should have focused only a few meters in.
I'll try to remember to bring the slide to the office and getting it scanned so you understand better what I'm trying to explain.
Many thanks for your time.
#6. "HFD" | In response to Reply # 5Thu 07-Sep-00 11:35 AM
The autofocus lenses (primes) have DOF marks, but many of these are reduced to the last two stops... my MF 20 and 24mm lenses have marks for f5.6. It is not always best to close all of the way down, because of image degrading diffraction. If a lens is at its sharpest at f8.0, and you could get the depth you need at that stop, why go lower? I see in your profile that you use a Leica M camera, so do I. With the skills you need to operate that camera, losing some of your function on your Nikon, by using AIS lenses, should not be that big a deal.
I have my personal prejudice based on bad experiences, but the longevity of manual focus AIS lenses is proven. Any initial upfront cost will be recouped after many years of flawless operation. If you really want a good general purpose wide angle, the 24 is probably more vestal than the 20, (both have their fans). I have both, but would be more inclined to grab the 24 for most situations.
#7. "RE: HFD" | In response to Reply # 6Thu 07-Sep-00 12:02 PM
many thanks for all the input, feels like reverting back would be way to go, so I'm going to keep my eyes open for a 24mm.
Since you brought up Leica, where this problem wouldn't occur, as you see I have only a 35mm so far, since I only got it in the beginning of this year. I feel that the 90/2.8 Elmarit-M would be great to have as well as a complement. Any comments?
#8. "leica" | In response to Reply # 7Thu 07-Sep-00 12:23 PM
I have a Leica M2 and M6,with 35 and 50mm summicrons and 90mm elmarit. I would always enjoy to offer my thoughts and opinions on this camera system, however, this being the Nikonians, I would rather just do direct e-mail. Feel free to go directly to my address:
I am kind of a control freak, so I can't give over to a computer, the controls of photography. I've tried, but my nature makes me question and check continuosly... so I gave up and just stay manual... Leica and Nikon, with manual focus prime lenses. This may be wierd in this day and age, but it gives me great satisfaction, and I'm not at the mercy of the "next model", which cancels the use of my current equipment. The shelves of any camera store is full of outstanding used lenses just waiting for old fashioned guys like me.
#9. "RE: more thoughts" | In response to Reply # 5vfnewman Basic MemberThu 07-Sep-00 09:43 PM
First, I'd like to address something you said in your very first post about hyperfocal distance. You said:
"The hyperfocal distance is when you have everything sharp from front to end..."
Rigorously speaking, hyperfocal distance is defined as "the value of a particular focus setting of the lens which makes the far limit of depth of field equal to infinity" (_The Manual of Photography_, 8th Edition, Jacobson et. al. 1988, p. 43)
When a lens is set to the hyperfocal distance, the far limit of DOF is at infinity, but the near limit of DOF still has a finite value. For example, using "f/calc" (a free utility available on the internet) the hyperfocal distance (henceforth abbreviated as "H") for a 600mm f/4 lens at f/4 is about 8949 ft. The far limit of DOF is infinity, and the near limit of DOF is 4474 ft. This would hardly make everything sharp from front to end, but for an aperture of f/4, the depth of field is maximized.
A 28mm lens at f/5.6 has an H of 13.7 ft, and a near DOF of 6.9 ft. Even with a wide angle lens, there is clearly a real limit to the near limit of DOF.
In the case you cite above, if you were using your 80-200 at the widest setting and f/5.6, the H calculates to be 112 ft. If that is the distance you set the focus to, the near limit of DOF is still 56 ft. At 80mm and f/5.6 there is no way you can have anything closer in focus AND still have infinity in focus.
My point is (and forgive me if you understand this already), that just because you focus a lens at its H does not mean that _all_ distances will now be in focus. You have only _maximized_ your DOF. There are still limits.
Now to address the question you put to me: I just looked at my Nikkor AF 20mm f/2.8. It has DOF markings for f/5.6 and 11 only. It's a real shame that they couldn't have gone to an infinitesimal additional effort and put the mark for f/22 there. At least then one could reasonably interpolate all the apertures. Why they didn't do this is beyond me.
Additonally, you mentioned that the F5's metering system is not working 100% with non-D lenses. Nikon claims that distance information is used in the calculation of ambient light exposures, but as far as anyone can tell, the effect is negligible. So, for ambient-light shooting, you really aren't loosing anything by using a non-D AF lens. The D technology does make a difference in the performance of TTL flash metering. Non-AF lenses do limit the capabilities of the metering system.
Please respond if my explanation isn't clear.
#10. "RE: more thoughts" | In response to Reply # 9Fri 08-Sep-00 03:13 AM
apologies for not having the correct terms for the HFD, actually never knew this discussion would come to this level.
Your thorough explanation on the f/5.6 is quite clear, however as I wrote I shot wide open at f/22 to maximise the DOF, which is not to say that the HFD is maximised which it isn't as we know.
The shot which has explained before was not focused at infinity, but more likely 1/3rd in, but seeing the shot itself it seems that I should have focused closer to myself, since DOF works behind the focused distance and not knowing the HFD.
I think I need to do what Al suggested to burn some film together with notes for the zooms and look for an 2nd hand 24mm AIS.
However it would not have helped me in this shot since required a longer foacl length, but the HFD issues are as discussed and suggested most common in wide angle lens shots.
I do not know if we are confusing each other by these mails, hope not.
#15. "lenses still need DOF marks" | In response to Reply # 12Tue 19-Sep-00 12:21 PM
Any charts or graphs for computing depth of field is still not as efficient as the marks being on the lens... where they belong. For one thing, if using a zoom, how do you use the charts for 39mm or 64mm? I have these charts in many of my photography books... the math is a constant, so they are readily available even in older books. They are only printed for standard focal lengths, so the advantages of zooms are ignored... fine tune the framing with an in-between focal length and where are you at.
Additionally, these charts are good for figuring the distance to focus at specific f-stops to reach near focus to infinity. That is only half of the value of depth of field marks... the other half is a specific range (zone focusing) that does not reach infinity, like the previously mentioned group shot. With a well marked lens it takes less that five seconds to determine the range and f-stop required to cover the group.
1. focus on the first row.... 6 feet
2. focus on the last row.... 10 feet
3. move the 6 to 10 foot range until it lines up between two DOF marks... f11 for a 50mm lens
4. set camera for f11 on aperture priority and shoot
How can referring to charts be faster and more versatile than that? Not every photo is a "from here to infinity" type picture, so a comprehensively marked lens will make life so much easier. Anytime you don't need to carry something else simplifies the process... and isn't that what all of these improvements are suppose to do? In the 1980's Nikkor zooms had DOF marks that curved to work for the shortest and longest lengths... and every intermediate focal length.
I still contend... the new lenses are missing something important.
#16. "RE: lenses still need DOF marks" | In response to Reply # 15WAn Basic MemberWed 20-Sep-00 04:59 AM
Unfortunately there is another drawback in AF lenses: the focusing scale is too short. It is probably good for AF motor (less tork needed), but it makes the metering and setting the DISTANCES on the scale a very hard job.
What a pity!