Hyperfocal help for a thicko!!!

swag72

swag72

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Sara
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I am trying to understand hyperfocal distances in order to adress landscape photography. I know that there are many advocates on here of the 1/3rd rule, but I REALLY want to learn the hyperfocal method.

I have looked at the DOF master on the internet - Great but leaves me with a problem. Have dowloaded the DOF programme onto my PC, excellent I thought.

My problem is this. In the field, so to speak, where I have no access to my PC and do not have a programme to do it for me, is there a SIMPLE chart I can use for all situations? I thought I had it on the PC prog, then realised that if the distance is different between each landscape then the focussing distance is different - I think? :thinking:

Oh hell :thinking: I just don't know any more!!:bonk: Need a chart I can take out with me.
 
Hyperfocal distance is the distance at which you need to focus with a given lens and aperture combination to give maximum depth of field from the far distance to close up. The far distance should extend to infinity.

The HD will vary with the aperture and lens used just to make life more difficult. One of the sad things about modern digital lenses is we've lost a proper depth of scale on the lens barrel.

You really answered your own question though - a simple chart tucked in your gadget bag which you can refer to is the way to go. :thumbs:
 
OR:-

This looks handy and bag/pocket sized.

CLICKY
 
Suvv said:
Have you looked here?
http://dofmaster.com/charts.html
Download the calculator, enter your lens details etc & print out the chart.
This may be the one you have already got, if so I apologise
Click to expand...

Hi Suvv, I have already got this one - Maybe I've got the wrong end of the stick, but isn't this only good for one specific picture where your focal point is xx metres away? Am I right in thinking that if that xx metres changes on a different pic then this chart needs to be redone with those new measurements?

Is it the same regardless of all distances? So one of these for each lens will work in that case, right?:help::bonk:

Am I being a total idiot?
 
LOL. Have a look at this chart Sara, which is probably easier to understand.

CLICKY

At least with this chart you could print out a version for each of your lenses.
 
Thanks Cedric. 2 questions raised here.

1) I use the distance in feet to determine where the main focus wants to be in the picture right? Then go across until I get to the aperture I'm using, and that tells me where I want to be focussing?

Am I understanding this properly?

2) How the hell do I use this for my zoom that I use for landscapes?

Ps. I hope being a total thick idiot is helping some others out there!!!!:D
 
swag72 said:
Thanks Cedric. 2 questions raised here.

1) I use the distance in feet to determine where the main focus wants to be in the picture right?
Click to expand...

Right!

Then go across until I get to the aperture I'm using,
Click to expand...

Right!

and that tells me where I want to be focussing?
Click to expand...

No. It tells you how far DOF extends (at that aperture) both behind and in front of the distance you chose in Step1.

2) How the hell do I use this for my zoom that I use for landscapes?

Ps. I hope being a total thick idiot is helping some others out there!!!!:D
Click to expand...

You select the focal length on the chart to match the focal length you're actually using your zoom at for the shot.

LOL. You're not being thick Sara, and these charts could be better I reckon. ;)
 
CT said:
It tells you how far DOF extends (at that aperture) both behind and in front of the distance you chose in Step1.
Click to expand...

How does this relate to Hyperfocal distance? I have looked at the DoF disks in your previous link - Looks like a great idea ......... but how do these tell me WHERE I need to focus?:bang:
 
swag72 said:
Thanks Cedric. 2 questions raised here.

1) I use the distance in feet to determine where the main focus wants to be in the picture right? Then go across until I get to the aperture I'm using, and that tells me where I want to be focussing?

Am I understanding this properly?

2) How the hell do I use this for my zoom that I use for landscapes?

Ps. I hope being a total thick idiot is helping some others out there!!!!:D
Click to expand...

I`m in the same boat... so your helping me as I was just gonna start this type of thread and ask all these questions. :D

I`m struggling a bit with it too tbh... trying to work out how to use it with modern lens`s is not easy.

Does anyone know of a chart that`s for (or would do for) the Tokina 12-24mm?

Thanks for starting this Sara. :D

:)
 
Hi Sara
I'm not sure but you may be confused about Depth of Field (DoF) & Hyperfocal Distance (HD).

DoF is the extent of distance from the lens that the picture will have acceptable sharpness.
If you look at the Depth of Field Table that CT linked to you can see that for a 50mm lens on a Canon 40d if you focus at 20 feet then anything between 16 feet 11 inches and 24 feet 6 inches will be acceptably sharp.
That distance between 16ft 11in and 24ft 6in is the DoF. Anything nearer or further than those distances will appear blurred as out of focus points do not focus to a point at the sensor but are actually small circles, and at distances outside the depth of field the circles are large enough for the eye to see them as a blur. Within the DoF things nearer or further than the distance you are focused on are still small circles at the sensor but are so small that the eye sees them as points. If you enlarge the picture too much, or view a print with a magnifying glass you will see the small circles.
If you use a larger aperture then the circles will be larger and you have a reduced depth of field, if you use a small aperture the circles are smaller and you have an increased depth of field.

If you are taking pictures of a landscape you often want the maximum DoF and you want the horizon in focus. If you simply focus the lens on the horizon, which is normally infinity on the lens, then the DoF for the same 50mm lens considered above will be from 305 feet to beyond infinity (whatever that means). To get the maximum DoF you need to focus the lens at the Hyperfocal Distance. In this case the HD is 305ft, the Dof is then from about 150ft to Infinity. This HD is correct for a 50mm lens at that aperture, other apertures and focal lengths will have different HDs.
Hyperfocal Distances are only used if you want the maximum DoF up to infinity
 
Thanks Suvv, got that difference well and truely now:thumbs: Great explanation.

So................ How do I get a nice compact and useable guide to HD's for difference focal lengths on my zoom lens? How do people do it in the field with no access to gadgets and PC's?

All I want is a simple chart!!:bang::bang:
 
If you downloaded the program in the link I gave earlier you can use that to print a chart for your various zoom lenses. Enter the Zoom settings in the Short Lens Length & Long Lens Length boxes, enter the Max & Min distances you may be using and enter the f stop range of the lens. Then print out the chart and take it with you.
 
Suvv said:
If you downloaded the program in the link I gave earlier you can use that to print a chart for your various zoom lenses. Enter the Zoom settings in the Short Lens Length & Long Lens Length boxes, enter the Max & Min distances you may be using and enter the f stop range of the lens. Then print out the chart and take it with you.
Click to expand...

I thought I had this one sussed, before I thought about it. If I print this off, I'm not going to know the min and max distance I am using until I get there to take the picture....... Right? Or am I missing something?!!
 
Yes thats right.
However what is the max aperture of your lens?
You only need the line for that aperture to meet the line coming up from the 55mm focal length. Whatever focus distance that corresponds to is the max distance you need. Just set the min to 1 for now, if you find you do not use such near distances print a different chart later.
 
This is how I do it.
I have a hand calculator that is programable (CASIO 730xp) with my prog on it. Just a few key pushes and I have all the info. Trouble is I never bother to use it.
 
As the HD = FL^2/(a * CofC)/1000. Thats great, after you have calculated this HD, all you have to do now is find an object that is this distance away from you,
What a load of rubbish.
 
oldfella said:
As the HD = FL^2/(a * CofC)/1000. Thats great, after you have calculated this HD, all you have to do now is find an object that is this distance away from you,
What a load of rubbish.
Click to expand...

So how do you get maximum DoF from infinity back towards the camera?
 
swag72 said:
My 17-55mm, wouldn't bother doing landscapes with anything else. You?
Click to expand...

12-24mm Tokina...

It`s new and I have to say seems very sharp, I`m happy :love: with it but would be happier if I could get this HD sorted/understood :gag: lol...
 
Using the "f/8 and be there" principle, you could simplify things to:

17mm HFD=2m DOF= 1m to infinity

21mm HFD=3m DOF= 1.5m to infinity

24mm HFD=4m DOF= 2m to infinity

28mm HFD=5.5m DOF= 2.7m to infinity

35mm HFD=10m DOF= 4.5m to infinity

Focus on a point at the hyperfocal distance (HFD) to get the the depth of field indicated.
 
Have you missed the link to this posted by CT above? Here is another one, where you can buy this very handy DoF calculator, ExposAperture2, for £25 from Robert White:

http://www.robertwhite.co.uk/product.asp?P_ID=537&P=Expo-Aperture2

If all you want is hyperfocal distance, that is just one focus setting for each focal length and f/number. That's say half a dozen numbers to write down. Even for a zoom, all you have to do is input the numbers from an on-line calculator, and note the HD for all the focal length points marked on your lens, at all the apertures. Let's say another six focal lengths. You should be able to get all that down onto something hardly bigger than a credit card to carry with you.

But if you want to calculate depth of field over a variety of different situations, this can get a bit confusing so I highly recommend that ExpoAperture thing as it is so easy to take with you and use quickly.

Another thing about the ExpoAperture disc is that in using it you will quickly understand how and when depth of field changes, and it will become intuitive. Aparently it's used in teaching quite a lot.

The other thing I'll say is that many landscapers are wary of hyperfocal distance. It does not always deliver as much sharpness as they's like because it pushes everything to the limit of acceptable sharpness, according to agreed international standards, and you might not agree with these standards in your own work.

There's a simple way around this though, just by closing down an extra stop. So set your HD according to the table/calculator at, say, f/5.6 then close down to f/8 to make certain everything is really crisp.

Richard.
 
I think I may just get one of those discs you know. Then write down the hyperfocal distances for a range of focal lengths on my lens. Thanks for all the input guys. You have made this an interesting read :thumbs:
 
Hoppy made a very good point- there's only one hyperfocal distance for each aperture of a given lens. Once you've ascertained what those distances are, all you need is a simple bit of card in your bag listing the hyperfocal distance for each aperture. That disc looks like a good idea to me Sarah. ;)
 
CT said:
Hyperfocal distance is the distance at which you need to focus with a given lens and aperture combination to give maximum depth of field from the far distance to close up. The far distance should extend to infinity.

The HD will vary with the aperture and lens used just to make life more difficult. One of the sad things about modern digital lenses is we've lost a proper depth of scale on the lens barrel.
Click to expand...


Absolutely! But its zoom lenses that are the problem not digital ones!

Although it always seemed to work for me, someone on yesterdays thread said you should never, ever use the DoF scale on a lens barrel for accurate focusing.

You can also use the DoF preview button on your lens to assist.
 
You lot have confuddled the bejesus outta me...........:eek:

I stick to my old 35 F2 prime, does using a zoom not complicate things to the n`th degree?

Are things easier with a widish prime?

Maybe I should hit the sack?


:shrug:
 
:lol:

zooms just change the sheet completely, hyper focal distance is different for every focal length.
At least with a fixed focal length, there's only one sheet, and if you stick to f/8 f/11 f/16.....its just three columns.

20mm :love:

or stuff it and focus on 1/3rd
 
Or why not print out the chart for your zoom at A6 size & take it with you ?
 
The DOFMaster iphone app is pretty useful. I may actually use it next time I'm out taking shots!
 
reading this got me interested.

I downloaded the DOFmasters windows program to print out that circular chart. and it does for upto 4 focal lengths.

Now can someone please explain how it works?

there is series of distance scales on the edge ring and then focal lengths with apparent f-stop marks on the inner disc. I am really confused. the online calculator was comprehensive enough.

my idea was to print out this disc thing for each zoom lens, so it covers a good zoom range and extrapolate between the focal lengths

screenshot.gif
 
That's pretty straightforward Ricky. The example shows a 50mm lens focused at infinity. It doesn't show the aperture used at that starting point, (it's probably f2) but you can see if you read to the left of the arrow that at that aperture DOF extends from infinity to 100 feet.

At F4 it extends from infinity to about 75 feet. At f22 it extends from infinity to 12 feet. Obviously you can read off the DOF for all the intermediate apertures.

This is a bad example image though as focusing at infinity doesn't give you the hyperfocal distance for maximum DOF. To do that you need to rotate the outer scale past the focusing arrow and align the infinty mark with one of the apertures on the right side of the scale. The arrow pointer will then point at the hyperfocal distance you need to focus at FOR THAT APERTURE. The aperture no.on the right side will show the far DOF (infinity) while the corresponding aperture no. on the left side will show the near limit of DOF.

Hope that helps?
 
In short Rick, you don't align the infinity mark with the focusing arrow - you align infinity wth one of the aperture nos. on the right of the focusing mark. It should all become pretty clear once you do that. :)
 
Here's an example using f22. As you can see I've aligned infinity with f22 on the right side of the index. By looking at f22 on the left side of the index you can see that DOF extends fom infinity to 6 feet, which actually sounds about right.

The arrow is now pointing to the distance at which you need to focus on your lens to achieve this DOF, or put another way ..... the hyperfocal distance. In this case it's 12 feet.

3226427453_f5984289d7_o.jpg
 
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