Hey Lawrence... about DOF... [Archive]

lkeeney

09-15-2005, 08:18 PM

wazza wrote:
Did you ever figure out all that stuff about getting a \'blurry\' background?

Cheers
Wazza

No, I am still puzzled about getting a blurry background.

I have been able to get a nice shot of my grandson, similar to the photo Dean posted. However, this was a head shot and was done with the 14-54mm lens at a close distance.

My initial problem was with the car shot I posted on dpreview, where I was using the 50-200mm lens.

After taking that shot, I thought I had it figured out somewhat. I purchased a #4 ND filter that I thought would allow me to use the lens at its wideest openening that I thought would fix my problem. Last week, while on the Bikini Jam shoot, I used the 50-200 lens with the ND filter, but when I shot the models at full height, I still could not get the blurred background.

There is somethng here I just don\'t understand.

Lawrence

wazza

09-15-2005, 08:26 PM

Which photo at the Bikini Jam, how far from the background was she?

gunnerx

09-15-2005, 08:48 PM

Would this help? http://www.dofmaster.com/dofjs.html

admin_old

09-15-2005, 09:13 PM

shallow DOF is hard to do on our lenses.... in none macro areas. you have to get close and keep them open. I am hoping that the next batch are more compact cam, and more SLR, which I think they will be. Part of it is the sensor size that causes the problems.
I put together this to show in about 2 minutes. 14-54mm flash, E-1.
http://www.fourthirdsphoto.com/pictures/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=875&g 2_serialNumber=1&g2_GALLERYSID=fb7f17275c13fc5801c 40202564cdef5
The important part is the chair to my wife\'s side, and not her. IT is just a standard shot she is sitting on a chair, 4 feet from a wall (about).
When I was close I was able to blur the background. (I even sharpened it a bit to show.)
In the shot on the right I am very far back the lens reads infinity. And it is all wide open.
So to blur backgrounds shoot wide open, and get close. And good luck.
It\'s not the greatest of shots, but its an example.
T

Post edited by: tspore, at: 2005/09/15 22:16

lkeeney

09-15-2005, 10:34 PM

wazza wrote:
Which photo at the Bikini Jam, how far from the background was she?

I will see if I can find a good example.

lkeeney

09-15-2005, 10:45 PM

gunnerx wrote:
Would this help? http://www.dofmaster.com/dofjs.html

I have tried to use similar DOF charts before and find I don\'t understand them.

As an example, I used this chart. I plugged in the E1 camera, 200mm lens, f3.4, subject distance of 40 feet. The chart indicates a Total Depth of Field of only 1.21 feet. In the case of my car photo, there was a tree that was about 15 - 20 feet behind the car and it was quite clearly in focus. Well, certainly not very fuzzy anyway.

I must be missing something here.

Lawrence

lkeeney

09-15-2005, 10:48 PM

tspore wrote:
shallow DOF is hard to do on our lenses.... in none macro areas. you have to get close and keep them open. I am hoping that the next batch are more compact cam, and more SLR, which I think they will be. Part of it is the sensor size that causes the problems.
I put together this to show in about 2 minutes. 14-54mm flash, E-1.
http://www.fourthirdsphoto.com/pictures/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=875&g 2_serialNumber=1&g2_GALLERYSID=fb7f17275c13fc5801c 40202564cdef5
The important part is the chair to my wife\'s side, and not her. IT is just a standard shot she is sitting on a chair, 4 feet from a wall (about).
When I was close I was able to blur the background. (I even sharpened it a bit to show.)
In the shot on the right I am very far back the lens reads infinity. And it is all wide open.
So to blur backgrounds shoot wide open, and get close. And good luck.
It\'s not the greatest of shots, but its an example.
T<br><br>Post edited by: tspore, at: 2005/09/15 22:16

Tony,

This is my problem. When I shoot full length shots of models as at the edge of a swimming pool I would like the far side of the pool to be completely out of focus. However, to get the full length shot I have to move a far distance from the model and by doing so, the background is always in focus.

Very frustrating.

Lawrence

admin_old

09-15-2005, 10:54 PM

I hear you.
With the 14-54 or 11-22mm and shooting a group shot at a wedding. I would love to get rid of the background many times. But as it is, its not happening. If I get to close they will be distorted. If I get to far away they are in infinity. 9 feet is not that far away at 35mm, but it is not wide enough on the 2X lenses.
This is one of the downfalls of the 4/3 format. I am hoping that the new lenses with not go to infinity at 3 meters. This is not the only factor in Boken, but it is one of the factors, that we have to keep in mind.
T

lkeeney

09-16-2005, 10:27 AM

lkeeney wrote:
wazza wrote:
Which photo at the Bikini Jam, how far from the background was she?

I will see if I can find a good example.

Wazza,

I think this is a good example of where the background is not completely out of focus. The background in this image is miles from the main subject, yet it seems to be in focus.

This image was shot at ISO 100, 54mm focal length, 1/2500 sec. @ f3.5.
http://fourthirdsphoto.com/components/com_simpleboard/uploaded/images/sample.jpg

wazza

09-17-2005, 03:48 AM

Well Lawrence,

You have had me and my brother (who is visiting with his E-300) running up and down the street trying to work this out.

And I think we have....

The background is blurred, but the problem is the amount of background which has to be put into the frame. You could have a kilometer of coastline in this shot, and you have to try to fit 1km of info into the frame, so the perception of how we see the blurriness is not perhaps as you would like due to the amount of info required to be recorded.

If you were to double your focal length, and back up the appropiate distance, you would have roughly half the coastline in the shot streatched accross the frame. This would mean approximately half of the info needs to be shown, therefore our perception of the background would be that its blurrier.

Where this gets hard for you as opposed to the bird shots you see, is you are shooting a much bigger target, so inherently you need to have a slightly wider view to fit it all in, which also results in you having to have more background in the shot, therefor more info need to be recorded, therefor our perception of how the backgrounded is recorded is \"less blurry\".

Do you get what I mean???
Clear as mud???

I geuss you need either a larger apature lens (f/2 maybe?), a longer lens or a bigger sensor (which will introduce a whole new lot of problems).

Cheers
Wazza

lkeeney

09-17-2005, 09:22 AM

wazza wrote:
Well Lawrence,

You have had me and my brother (who is visiting with his E-300) running up and down the street trying to work this out.

And I think we have....

The background is blurred, but the problem is the amount of background which has to be put into the frame. You could have a kilometer of coastline in this shot, and you have to try to fit 1km of info into the frame, so the perception of how we see the blurriness is not perhaps as you would like due to the amount of info required to be recorded.

If you were to double your focal length, and back up the appropiate distance, you would have roughly half the coastline in the shot streatched accross the frame. This would mean approximately half of the info needs to be shown, therefore our perception of the background would be that its blurrier.

Where this gets hard for you as opposed to the bird shots you see, is you are shooting a much bigger target, so inherently you need to have a slightly wider view to fit it all in, which also results in you having to have more background in the shot, therefor more info need to be recorded, therefor our perception of how the backgrounded is recorded is \"less blurry\".

Do you get what I mean???
Clear as mud???

I geuss you need either a larger apature lens (f/2 maybe?), a longer lens or a bigger sensor (which will introduce a whole new lot of problems).

Cheers
Wazza

Wazza,

I understand what you are saying.

What I don\'t understand is the DOF charts. I plugged the numbers in for this shot into one of the DOF calculator programs, and it gave me a Total DOF of a little over 13 feet. From what I see this number has very little real meaning. There is just too much I don\'t know about this subject.

wazza

09-20-2005, 12:50 AM

lkeeney wrote:
wazza wrote:

Wazza,

I understand what you are saying.

What I don\'t understand is the DOF charts. I plugged the numbers in for this shot into one of the DOF calculator programs, and it gave me a Total DOF of a little over 13 feet. From what I see this number has very little real meaning. There is just too much I don\'t know about this subject.

Lawrence,

I think (and I don\'t claim to be an expert on the matter), if you could mark out the 13 feet on this pic, and zoom in, you will see that the subjects within this are in fact sharp. If you zoom in on stuff outside of this 13 feet, you will see they are not sharp.

I think the problem comes with the amount of info which has to be crammed into the frame (that km of coast line), infact I am not even sure the f/2 zooms could blur the background more than it already is here due to the nature of the shot.

As for the solution....???? I am already over my head on this one, I was hoping bumping it back up again might get someone who really knows their stuff so we can both know.

Cheers
Wazza

Bojan Volcansek

09-20-2005, 07:40 AM

As far as I understand DOF etc, the key to have background blurred (OOF) is the camera to subject distance. The shorter distance, DOF is shorter and background will be more blurred.

For the DOF itself, if the DOF is let say 2m \"around - back and forth\" subject, that means that EVERYTHING in that 2m will be IN focus. However out of focus area will not be always the same \"outfocused\".

Sometimes, like in example with the girl and photographer - citi line IS out of focus but not completely blurred. Why? Because distance from camera to the subject that is in focus is already quite big, and out of focus areas are inspite being out of focus not blurred enough.

Very similar like Lawrence\'s example with the car. Distance from camera to subject was big enough, so that background is OOF but not completely blurred.

Also \"bluriness\" will depend on the background. If background is more colour/contrast uniform, it will look more blurred then if background has higher contrast/eye recognizible shapes.

Our eyes are amazing when trying to recognize something. And they will often \"sharpen\" image automatically if they have anything to work with - anything that can be recognizible.

That is MY understanding of DOF, and OOF and bluriness.

If you really want to perform the test - rather simple one, try to change the distance between camera and subject and different background. Once when you perform the test, try to memorize what is good distance that you have background out of focus and then try to use that distance in the future.

Sincerely yours
Bojan

lkeeney

09-20-2005, 04:11 PM

Bojan Volcansek wrote:
As far as I understand DOF etc, the key to have background blurred (OOF) is the camera to subject distance. The shorter distance, DOF is shorter and background will be more blurred.

For the DOF itself, if the DOF is let say 2m \"around - back and forth\" subject, that means that EVERYTHING in that 2m will be IN focus. However out of focus area will not be always the same \"outfocused\".

Sometimes, like in example with the girl and photographer - citi line IS out of focus but not completely blurred. Why? Because distance from camera to the subject that is in focus is already quite big, and out of focus areas are inspite being out of focus not blurred enough.

Very similar like Lawrence\'s example with the car. Distance from camera to subject was big enough, so that background is OOF but not completely blurred.

Also \"bluriness\" will depend on the background. If background is more colour/contrast uniform, it will look more blurred then if background has higher contrast/eye recognizible shapes.

Our eyes are amazing when trying to recognize something. And they will often \"sharpen\" image automatically if they have anything to work with - anything that can be recognizible.

That is MY understanding of DOF, and OOF and bluriness.

If you really want to perform the test - rather simple one, try to change the distance between camera and subject and different background. Once when you perform the test, try to memorize what is good distance that you have background out of focus and then try to use that distance in the future.

Sincerely yours
Bojan

Bojan,

My problem is I am most interested in blurring the background when I am shooting a model full length, such as at a pool, or the beach. No matter what lens I use, if I crop the image so the model is full length I have never been able to blur the background. When shooting like this, there is very little I can do about the distance of the model from the background.

I have tried different lenses, added #4 ND filter to allow me to open the lens wide open, and nothing seems to help.

I have posted images on the lighting forum at dpreview and I always seem to get comments that I should have blurred the background. Are other digital camera better at doing this?

Lawrence

admin_old

09-20-2005, 05:52 PM

It is a serious problem for the 4/3 system as it stands. I am hoping that the 35-100 F2 will solve it. IF not then the 4/3 system will probably not go far in the minds of many. (Including mine) I see images all the time from Canon shooters they can... We will see.
T

lkeeney

09-20-2005, 06:20 PM

tspore wrote:
It is a serious problem for the 4/3 system as it stands. I am hoping that the 35-100 F2 will solve it. IF not then the 4/3 system will probably not go far in the minds of many. (Including mine) I see images all the time from Canon shooters they can... We will see.
T

Hi Tony,

I sure hope they come out with a lens that will give me this feature. I am 110% sold on the 4/3 system, and there are very other features, other than a few extra pixels, that I want.

Larry

admin_old

09-20-2005, 06:27 PM

I sure hope they come out with a lens that will give me this feature. I am 110% sold on the 4/3 system, and there are very other features, other than a few extra pixels, that I want.
ME Too!!
Blurry backgrounds, and High ISO. I would love . If I could get great ISO 3200 That looked like ISO800 on the E-1 I would take that over IS. I would rather have high shutter speeds. (If shooting a person, or object that moves it will be blurry at slower shutter speeds)
Anyhow we will see what they have to do.
T

First Light

09-21-2005, 12:53 AM

We do not need a new lens in order to shoot pictures with very out-of-focus (OOF) backgrounds with our E-1 and E-300 cameras. Many of the existing Olympus ZD lenses can easily do this. It isn\'t an equipment problem.

Sure, there are differences from one camera to the next depending on the size of its image sensor. But even though the DOF of a 4/3rds camera is approximately twice that of a 35mm film camera with the same FOV and f-stop, it won\'t have a significant effect on background objects in the far distance. Such differences are overshadowed by the real problem: the technique used.

It seems like there is a big misunderstanding of the DOF equation and how to use it. If you want the background to be way OOF (that is, very blurred) then you have to (1) keep the FOV small and (2) use a large aperture.

It is obvious why the mountains are only mildly OOF in the swimsuit model photo. The camera is too far away from the subject, making the FOV too large. A 35mm film camera shooting the same FOV with the same aperture wouldn\'t do that much better at blurring the mountains. The wrong technique was used to achieve a shallow DOF.

Don\'t ever expect to shoot a wide FOV and achieve a shallow DOF at the same time. They are opposites. Nor will using a wide aperture be enough compensate for a wide FOV. You must either move the camera closer to the subject to reduce the FOV or you must use a longer focal length to reduce the FOV. For example, the FOV could have been reduced by 2/3rds so that only the swimsuit model fit within the frame.

A better lens for this shot may have been the ZD 50mm f2.0 macro prime. Framing the model much tighter (smaller FOV) by moving the camera closer and having a wide aperture of f2.0 would have easily put the mountains way, way OOF. Just be prepared to add a neutral density (ND) filter sometimes when you do this in bright sunlight since a wide open aperture may result in overexposure.

Finally, how do you decide which technique to use to reduce the FOV? Whether you choose to move closer or use a longer lens will depend on the perspective that you want. The longer lens will give you a longer perspective which will make the picture look more \"flat\". A shorter lens will shorten the perspective and increase the sense of depth. But you also have to balance the amount of geometric distortion which will be greater with a shorter focal length.

NrthrnHrse

09-21-2005, 01:33 AM

I shoot with a Sigma 50-200 and I\'ve NEVER had a problem with getting a blurry background or Depth of Field with it. I primarily shoot with it over at least a 1/4th way zoomed and the background is usually a bit back.

Here is one example... http://fourthirdsphoto.com/components/com_simpleboard/uploaded/images/P8272466.jpg

NrthrnHrse

09-21-2005, 01:42 AM

Here is a picture of the same flowers, but the focal point is on the blue Pansey in one picture and the red/white Petunia in the other. Again with my Sigma 200 and I\'m quite a distance away. http://fourthirdsphoto.com/components/com_simpleboard/uploaded/images/P8182353.jpg

NrthrnHrse

09-21-2005, 01:43 AM

2nd picture
http://fourthirdsphoto.com/components/com_simpleboard/uploaded/images/P8182354.jpg

wazza

09-21-2005, 02:38 AM

Hi Northernhorse,

All 3 of your examples, especially the last 2 are very different from the pics Lawrence has provided. Your subjects are much smaller.

I think firstlight may have hit the nail on the head and eloquently stated that which I inequently tried to state.

Lawrence, does this help?

Cheers
Wazza

NrthrnHrse

09-21-2005, 02:54 AM

The last 2 pictures are demonstrations of how the focus of the camera can be. It wasn\'t meant to be comparisons to a human body.

The flowers were only a few inches apart, yet they were blurred because of the amount of zoom I was using with the lens and my distance from the subject. If you want to talk about the size of a subject, try shooting a horse show sometime! ;)

I was posting in response to the complaint that you can\'t obtain an OOF background with a 4/3 camera. I can and have quite consistantly in the short time I\'ve had the camera.

NrthrnHrse

09-21-2005, 03:58 AM

Also, the farther back I am and greater my zoom is (over 180) the more OOF my background is. Here are two more examples on much LARGER (horses) subjects. ;) I guess I must be using a much larger aperature at that point? http://fourthirdsphoto.com/components/com_simpleboard/uploaded/images/P7241710.jpg

Post edited by: NorthernHorse, at: 2005/09/21 05:04

NrthrnHrse

09-21-2005, 04:03 AM

2nd picture. Notice the jump in front is slightly out of focus, as is the jump behind. I\'ve noticed that my Evolt is very particular on what it focuses on and if I\'m not careful in AF mode it will pick up the rider instead of the horses head etc to focus on. http://fourthirdsphoto.com/components/com_simpleboard/uploaded/images/P7241836.jpg

wazza

09-21-2005, 04:45 AM

Yep, thats closer, these horses look a little bigger than Lawrence\'s models :) .

I guess though, looking at these, you still have a smaller FOV, which seems to be where the trick lies for OOF backgrounds.

Cheers
Wazza

lkeeney

09-21-2005, 09:53 AM

NorthernHorse wrote:
2nd picture. Notice the jump in front is slightly out of focus, as is the jump behind. I\'ve noticed that my Evolt is very particular on what it focuses on and if I\'m not careful in AF mode it will pick up the rider instead of the horses head etc to focus on. http://fourthirdsphoto.com/components/com_simpleboard/uploaded/images/P7241836.jpg

NorthernHorse,

Thank you for taking the time to post the nice images.

I think I have somewhat of an understanding of DOF in that I do use a ND filter, keep the lens fully open, use a fast shutter speed, and try to try to reduce the angle to reduce the amount of background visible. However, for the images I want to shoot (model full length at poolside, fashion model on runway, etc.) I find it impossible to achieve the blur that you have shown in your images.

I have no problem with blurring the background when shooting head shots.

The one thing I don\'t understand is the DOF charts where in one of my typical model shots they indicate a DOF of about 1 foot, yet the background that is hundreds of feet away is still not very blurry.

I guess I just don\'t feel like I have much control over how blurry the background will be.

Lawrence

lkeeney

09-21-2005, 09:54 AM

First Light

09-21-2005, 11:16 AM

It sounds like what is needed here is a table that compares the diagonal distance covered by the FOV verses the distance to the background behind the subject for different degrees of background OOF at various f-stops. Unfortunately, I\'m not aware of any such table. If they existed for digital cameras, they would change slightly, depending on the size of the image sensor because the sensor size determines the size of the circle of confusion or COC (an important component of the DOF equation).

Even with a large aperture like f2.0 I\'m sure that the ratio has to be pretty high (like 1:100 or 1:1000 or more) before the background will be strongly blurred. In other words, the background must be much more distant compared to the size of the FOV before it will be very OOF. Plus, the smaller the aperture (the bigger the f-stop), the bigger the ratio would be.

The background of the fashion runway shoot may be hundreds of feet behind the models but that may simply not be enough for the desired full-body FOV. For example, if you want to tightly frame a full-body shot, you may allow your FOV to cover a 7 foot height. If you\'re framing in portrait mode (vertical shot) then the diagonal FOV will be about 9 feet. If you need a 1:100 ratio between the FOV and the background distance for a very blurry effect at your chosen f-stop, then your background would need to be 900 feet away. But I\'m just guestimating here. You could determine you own ratios by setting up some test shots outdoors.

Remember that we\'re only talking about the distant background here. Any near background objects would be less OOF. So if you\'re shooting into an audience beside the fashion runway you can expect nearby spectators to be only mildly blurred.

In a case like this, the only variables you have left are the aperture and sensor size. You would probably need a medium or large format body with an f1.0 or f1.2 lens to push the background significantly further OOF without reducing the FOV.

russ.will

09-21-2005, 01:07 PM

It would appear that in the face of the onslaught of new technology we all forget to go back to basics. The DOF problem we are all suffering IS a result of smaller sensor sizes which bears no further discussion here as we are stuck with it.

The problem lies in the fact that with the almost total reliabilty of AF many of the manual focus lense markings have disappeared as nobody uses them or have forgotten how to. AF focuses on a subject. Whatever depth of field is available fore or aft of a subject is, as we know a function of aperture and relative distance between the camera/subject/background/focal length/sensor size.

We now have comparatively large DOF at all apertures on most lenses. Therefore only relatively extreme combinations of large aperture, long focal length and a large distance from subject to background versus camera to subject will provide the blured background we will require without further input. There is however a solution...

HYPERFOCAL DISTANCE

For a given focal length and aperture the DOF is fixed, however with increasing focal distance the DOF encompasses a greater range. If we all examine our 14-54s we will note that the distance on the scale is very small from 3m to infinity but very much larger for 3m back to 1.2m. Yet a subject taken at either of these distances will, proportionally, have the same amount of DOF fore and aft. NOT the same amount, but the same percentage. What we need to do is to move the DOF relative to the subject whilst maintaining subject focus.

http://www.fourthirdsphoto.com/pictures/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=976&g 2_serialNumber=2&g2_GALLERYSID=683bd7bbcb91e57b2e7 a079e8c4fe240

Above you can see a theoretical focal distance of 25ft at an aperture which for the sake of argument is F8. Using the Hyperfocal scale between the distance window and the aperture ring we can see that everything is in focus from infinity down to about 12ft. You have a sharp image from 12ft all the way to infinity which is great for snapshots of your wife/husband/life partner pointing at mountains but not where you want the bikini clad dream boat to remain the centre of attention.

We need to utilise the hyperfocal distance thus:

http://www.fourthirdsphoto.com/pictures/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=972&g 2_serialNumber=2&g2_GALLERYSID=683bd7bbcb91e57b2e7 a079e8c4fe240

Knowing that we have selected F8 we move the 25ft marking toward the F8 hyperfocal marking. As we can now see 25ft is still within the depth of field available but everything beyond has been pushed well outside of this range. We have an out of focus background. Of course we now have even more infocus foreground down to about 10ft but as this should be clear air you won\'t see it. It\'s not about where you focus but where you place the DOF. The subject hasn\'tmoved, nor the camera, nor the aperture - just the DOF.

This effect is increased with focal length, hence the \'fan\' of lines you used to get on old push/pull zoom lenses with the widest part of the fan at the widest angle end of the lense with the largest DOF. The break even point DOF movabilty against ease of adjustment was in the range of 100 to 135mm which is why these were the 35mm weapons of choice for portraiture. With our weeny sensors this same point has been shifted up to 200mm plus (35mm equivalent).

Problem is that these massively useful lines disappeared with the advent of twist to zoom and AF, which is why we now need to carry DOF charts and why we really need to learn to use them. This is one aspect of photographic technique that has not been made quicker with technology, but owing to the laws of physics, cannot be worked around at the time of shooting.

Post edited by: russ.will, at: 2005/09/21 14:12

Post edited by: russ.will, at: 2005/09/21 14:33

Post edited by: russ.will, at: 2005/09/21 14:35

Post edited by: russ.will, at: 2005/09/21 14:35

Post edited by: russ.will, at: 2005/09/21 14:37

First Light

09-21-2005, 03:06 PM

russ.will wrote:
...The DOF problem we are all suffering IS a result of smaller sensor sizes... ...Therefore only relatively extreme combinations of large aperture, long focal length and a large distance from subject to background versus camera to subject will provide the blured background we will require without further input. ...
I must respectfully disagree with this assessment because it places the emphasis on our equipment. Yes, it is true that smaller image sensors have contributed to a generally longer DOF. However, we still have adequate DOF range with many available lenses to create excellent portrait-style photos with nicely OOF backgrounds.

The examples offered here (swimsuit model photo with wide FOV and full-body shots on a fashion runway) would still be difficult shots for a full-frame dSLR like a Canon 1Ds MkII or a 35mm film camera to achieve a very blurred background. So I don\'t see our situation today as being that \"extreme\".

It seems clear to me from reading this thread that the greater issue is one of education about general photographic technique. Russ, your explanation of how to locate the subject farther back in the DOF region is great and a very useful tool that addresses this educational need. However, the DOF will often be so shallow when using typical wide apertures settings (f2.0 to f3.5) that it won\'t make as big a difference as desired. I\'ve seen the technique used more often to maximimze the DOF in a landscape shot at high f-stops (small apertures).

Let\'s return to the swimsuit model photo. It was shot with a focal length of 54mm and aperture of f3.5. If the E-1 was 20 feet away from the subject, the total DOF would be about 4.3 ft. If the camera was 30 feet away from the subject, the total DOF would be about 10 ft. In either case, adjusting the focus point forward so the subject is near the rear limit of the DOF region would not have been enough to put the distant mountains way OOF as desired.

russ.will

09-21-2005, 05:44 PM

30ft with a 10 ft DOF - Thats a DOF OF 30%. Look at your 14-54 and if focusing at 30 ft, infinity is well within the DOF. You have to pull the focus back to about 8ft to start bluring the background. Whatever you may think, the emphasis IS on the equiptment because this is a problem related to the physics that govern it.
http://www.fourthirdsphoto.com/pictures/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=162&g 2_serialNumber=1&g2_GALLERYSID=913a8603614c6fdd487 7c057b0064a04
I posted this one the other week in the WDYSPPTW section. 47mm, F3.5 distance about 8ft, but the background is OOF enough not to distract. Note the relative sharpness of the railings infront of the sprog compared to behind. AF+MF then I focused manually to about 2ft in front of where the camera was focusing. In the viewfinder the kid was bordering on blurred but I knew the natural DOF would keep him in focus. Trust me, it works with experience and practice.

As regards the shallow depth of fields at longer focal lengths - that\'s exactly my point. Our 1/2 diametre sensors give you twice the depth of field of a full 35mm frame. You need to be getting on twice the focal length to claw the shallow DOF advantage back.

54mm, 30ft and no appreciation of hyperfocal distance - of course the background looked sharp.

Russell

Post edited by: russ.will, at: 2005/09/21 18:48

NrthrnHrse

09-21-2005, 05:52 PM

Great example Russell and thanks to First Light and yourself for such a great discussion!:kiss:

gunnerx

09-21-2005, 07:27 PM

There\'s a good tutorial using the EVOLT on the Olympus site too.

http://olympusdigitalschool.com/e-system_cameras/e-300/EVOLT_E-300_Controlling_Depth_of_Field_in_Outdoor_Portrait s/index.html

barondla

09-21-2005, 09:03 PM

Use one of the OM 50mm f1.8, 1.4, or 1.2 lenses to get less dof. Even the dz 50 f2 would help.
thanks
barondla

pixelmaniaman

09-21-2005, 10:32 PM

I can\'t say I have really noticed the DOF problem taking into consideration the type of work I have recently done with the E300 & standard 14-45, but now I am going to do some tests. Has anybody seen this problem referred to on any other DSLR sites.
L

lkeeney

09-21-2005, 10:45 PM

I want to thank everyone for all the information on DOF. I am going to have to take some time to digest everything I have read.

I like the idea of the fast 50mm lenses. I sure wish I could try some before I put out my money.

Lawrence

admin_old

09-22-2005, 11:28 AM

Here is a DOF chart I found for the E-1 at my43.
http://myfourthirds.com/document.php?id=11015
Also if you have a Palm or pocket PC you can download this:
http://www.olympus-pro.com/eu/en/downloads/depthoffieldcalculator.html
Finally if you have OSX 10.4 (Widgets) You can try this widget:
http://www.apple.com/downloads/dashboard/calculate_convert/dofcdepthoffieldcalculator.html

T

lkeeney

09-22-2005, 11:57 AM

tspore wrote:
Here is a DOF chart I found for the E-1 at my43.
http://myfourthirds.com/document.php?id=11015
Also if you have a Palm or pocket PC you can download this:
http://www.olympus-pro.com/eu/en/downloads/depthoffieldcalculator.html
Finally if you have OSX 10.4 (Widgets) You can try this widget:
http://www.apple.com/downloads/dashboard/calculate_convert/dofcdepthoffieldcalculator.html

T

Hi Tony,

I have been using the DOF chart on the Digital Diver site http://www.digitaldiver.net/dof.php as it also has information for the E1 camera. However, when I plug in the information for the photo of the photographer taking a photo of the model, with the mountains in the background, it indicates the Total DOF to be approximately 1 meter (I originally read this as being 1 foot), But as you can see from the photo, the mountains, which are many miles away, and not very blurry. This tells me a DOF chart is of very little help when shooting an image like this.

I tried reading the Lens Tutorial at http://www.photo.net/learn/optics/lensTutorial and found it to be a little over my head the first time through. I am going to have to really study this tutorial to see if I can understand everything I think I know about lenses.

I guess what it comes down to is that my test shots don\'t seem to agree with the DOF charts, or I don\'t understand what \"Total DOF\" really means. It seems the Total DOF has very little to do with the point at which the image becomes blurry. But then again, blurry is subjective, so what do I know.

Lawrence

lkeeney

09-22-2005, 12:01 PM

Tony,

You may want to consider adding a link to this \"Lens Tutorial\" page. http://www.photo.net/learn/optics/lensTutorial

Someone here, who is smarter than I am, may be able to understand it.

Lawrence

Bojan Volcansek

09-22-2005, 12:09 PM

lkeeney wrote:
I want to thank everyone for all the information on DOF. I am going to have to take some time to digest everything I have read.

I like the idea of the fast 50mm lenses. I sure wish I could try some before I put out my money.

Lawrence

Dear Lawrence,
if you have OM adapter I can send you one of my OM 50mm f1.8 for a test.
Or you can simply buy one if it, prices were really low when I was getting them - around 20$ (both US and CAD) each.

I forgot where are you located - I bet 2 way shipping would be more expensive then buying one. But if we are near (I\'m in Toronto, Ontario), we can meet in person.

I\'ve just checked KEH, now it is slightly more expensive, in bargain condition 10USD, in excelent 27USD
http://www.keh.com/shop/product.cfm?bid=OM&cid=06&sid=newused&crid=1210588 5

they also have f1.4 and even that one is not too expensive 69USD in excellent condition.

If you have some local store or some pawn shop nearby you can check in their used equipment, it should be rather inexpensive.

Sincerely yours
Bojan

lkeeney

09-22-2005, 02:10 PM

Bojan Volcansek wrote:
lkeeney wrote:
I want to thank everyone for all the information on DOF. I am going to have to take some time to digest everything I have read.

I like the idea of the fast 50mm lenses. I sure wish I could try some before I put out my money.

Lawrence

Dear Lawrence,
if you have OM adapter I can send you one of my OM 50mm f1.8 for a test.
Or you can simply buy one if it, prices were really low when I was getting them - around 20$ (both US and CAD) each.

I forgot where are you located - I bet 2 way shipping would be more expensive then buying one. But if we are near (I\'m in Toronto, Ontario), we can meet in person.

I\'ve just checked KEH, now it is slightly more expensive, in bargain condition 10USD, in excelent 27USD
http://www.keh.com/shop/product.cfm?bid=OM&cid=06&sid=newused&crid=1210588 5

they also have f1.4 and even that one is not too expensive 69USD in excellent condition.

If you have some local store or some pawn shop nearby you can check in their used equipment, it should be rather inexpensive.

Sincerely yours
Bojan

Bojan,

I thought I responded to your message, but I must have pressed the wrong button.

Thank you for your suggestion and for your offer to loan me a lens.

I like your idea about using an OM lens. I looked at the f1.4 at KEH, and like that one. However, I don\'t have an OM adapter for my E1, and the prices I find are close to $200 USD. I have no problem with the lens price, but the adapter is pretty expensive for a test. Do you know where I may find one that is less expensive?

I live outside of Las Vegas, so I doubt we will get a chance to speak in person, unless you want to take a nice Las Vegas vacation.

I will keep looking for an inexpensive adapter.

Thanks again.

Lawrence

Bojan Volcansek

09-22-2005, 02:42 PM

LAS VEGAS, wow,
well, then, we (my wife and I) can use you when we go to visit Grand Canyon, Zion and all other beautiful landscape around.

About the adapter, why don\'t you ask one from Olympus? They were providing them for free, and I think they are still doing that in US. Simply try to call them (phone # is: HOTLINE for E-1: 1/800-260-1625 is not available on Fridays, Saturdays) and ask them, I called them when we\'ve got our E1 (a year ago) and they send one, when it was available (about 2months after that), but I think they have them now readily available. They didn\'t even ask for the E1 serial number, just for the shipping address (Toronto, Ontario, Canada for me).

Hope this help,
and if you called them, let me know how was the conversation. I always have great time talking with them

yours Bojan

pixelmaniaman

09-22-2005, 03:04 PM

Hi, I just had an email from Olympus, the adaptor is no longer free. L

lkeeney

09-22-2005, 03:23 PM

Bojan Volcansek wrote:
LAS VEGAS, wow,
well, then, we (my wife and I) can use you when we go to visit Grand Canyon, Zion and all other beautiful landscape around.

About the adapter, why don\'t you ask one from Olympus? They were providing them for free, and I think they are still doing that in US. Simply try to call them (phone # is: HOTLINE for E-1: 1/800-260-1625 is not available on Fridays, Saturdays) and ask them, I called them when we\'ve got our E1 (a year ago) and they send one, when it was available (about 2months after that), but I think they have them now readily available. They didn\'t even ask for the E1 serial number, just for the shipping address (Toronto, Ontario, Canada for me).

Hope this help,
and if you called them, let me know how was the conversation. I always have great time talking with them

yours Bojan

Bojan,

By all means, if you come to Las Vegas please contact me.

I called the number you gave me and had a half hour conversation with the fellow. I was told Olympus did not make the OM adapter that they gave away. From what I understand, it was a deal where the manufacturer gave the adapters to Olympus for them to give away. In return, the manufacturer got feedback on how they worked, etc. so they could decide if this was a product they wanted to continue to manufacture. In any case there are no more available.

In talking with the fellow, he sort of talked me out of using the OM lens as he said I would lose a couple of f stops by doing this. He suggested I either look at Sigma, or wait until Olympus announces a faster 50mm lens. I\'m not sure about Sigma, as I don\'t want to purchase a plastic lens. I doubt they would be as sharp as a glass lens.

I think I will just wait for a faster 50mm Olympus lens.

Lawrence