F8 or Higher for small birds?

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Russell
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Hi, for those who photograph smaller birds, what F stop do you use most of the time? I when doing landscapes could get the scene in focus but with these small birds if I get the eye in focus the tail is OOF shooting at F8 on a Sony A9 at around 200 to 360 on the shutter. Thanks for any advice. Russ
 
I shoot wide open a lot of the time with my 200-600mm, so that would be f5.6 or f6.3
Although in the summer when there's usually more light I will generally use f8.
 
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It's very rare that I have enough light to be stopping down the lens. I normally shoot wide open (f6.3 with my lens at the moment).
And if I could afford to go even wider (aperture wise) I would.
 
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f/8-f/11 Is where my Tamron 100-400 is sharpest for birds.
 
Thank you for the replies, thinking small birds maybe better with a higher shutter speed even on a tripod so going out tomorrow weather permitting to test that out, even with a higher ISO better to get a sharp image I think. Russ.
 
Depth of field is dependant on the focal length, aperture and distance to subject. You will still need a fast-ish shutter speed to freeze the movement of the bird even if you’re on a tripod. Birds still move quite a bit even when perched.

I had fun trying to get a puffins face and beak all in focus. The problem I had was I was shooting from 2-3m away and the beak when face is about 2-3cm long. There’s a reason why most Puffin photos are shot side on!
 
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Depth of field is dependant on the focal length, aperture and distance to subject. You will still need a fast-ish shutter speed to freeze the movement of the bird even if you’re on a tripod. Birds still move quite a bit even when perched.

I had fun trying to get a puffins face and beak all in focus. The problem I had was I was shooting from 2-3m away and the beak when face is about 2-3cm long. There’s a reason why most Puffin photos are shot side on!
F7.1 on M43 for this one....100-400mm lens.

2020-11-15_03-07-59.jpg
 
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At my hide, where birds are small and usually 8 feet or so away, I use as small an aperture as I can get away with, usually around f8 and even then, all of the bird isn't sharp all the time. I have to at least have the eye sharp, this is a must. It's much easier side on and parallel to the senor, then you can go as wide as you like. That said, wildlife rarely sits still for long, so it's challenging.

If the bird is further away, it's easier but then you'll probably be cropping in and losing quality.

Wait until you try macro ;).
 
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Depth of field is dependant on the focal length, aperture and distance to subject. You will still need a fast-ish shutter speed to freeze the movement of the bird even if you’re on a tripod. Birds still move quite a bit even when perched.

I had fun trying to get a puffins face and beak all in focus. The problem I had was I was shooting from 2-3m away and the beak when face is about 2-3cm long. There’s a reason why most Puffin photos are shot side on!


^^^

This, fairly basic stuff without wanting to sound 'know it all' about things but a Depth of Field calculator will help you immensely.

Like this one but there are a few suitable apps for mobile phone use when out in the field.
 
^^^

This, fairly basic stuff without wanting to sound 'know it all' about things but a Depth of Field calculator will help you immensely.

Like this one but there are a few suitable apps for mobile phone use when out in the field.
Your right it is basic stuff but at the time I didn’t have a DoF app installed or any internet signal to check it (O2 mobile signal was pretty poor when I stayed on Skomer) and it was a pretty spur of the moment composition idea. It was nearly 5 years ago so I’ve got a bit better since but I still couldn’t give an exact DoF figure depending on the variables at the time (I know how it works so could work it out with some trial and error).
 
Your right it is basic stuff but at the time I didn’t have a DoF app installed or any internet signal to check it (O2 mobile signal was pretty poor when I stayed on Skomer) and it was a pretty spur of the moment composition idea. It was nearly 5 years ago so I’ve got a bit better since but I still couldn’t give an exact DoF figure depending on the variables at the time (I know how it works so could work it out with some trial and error).
On the Sony, you can switch to manual and use the yellow highlight thingys to show what's in focus and confirm dof quite quickly....
 
Your right it is basic stuff but at the time I didn’t have a DoF app installed or any internet signal to check it (O2 mobile signal was pretty poor when I stayed on Skomer) and it was a pretty spur of the moment composition idea. It was nearly 5 years ago so I’ve got a bit better since but I still couldn’t give an exact DoF figure depending on the variables at the time (I know how it works so could work it out with some trial and error).

My apologies, I typed the 'this' as i was agreeing with your post and not having an issue with it! Sorry for the confusion.
 
^^^

This, fairly basic stuff without wanting to sound 'know it all' about things but a Depth of Field calculator will help you immensely.

Like this one but there are a few suitable apps for mobile phone use when out in the field.
Sounds sense to me if you are unaware of the distances to DOF. Prior to venturing out check two or three distances/DOF and remember them.
 
You need to think more about shutter speed than aperture. Slow lenses will seriously hinder you also.
 
Depth of field is dependant on the focal length, aperture and distance to subject.
There's actually two separate things going on...
The focus tolerance (depth of focus) is determined only by the subject distance (relative size) and the physical aperture diameter (angle of incidence, not f#). This determines how sharp details are recorded relative to each other.
The depth of field is then determined by the magnification (+/-) of that recorded focus tolerance; either with focal length (lens/recording magnification), or with cropping/enlarging/viewing distance (viewing magnification).
I think this distinction is important, because you can't use a shorter FL to increase the DoField if you are then going to have to crop/enlarge the result more.

Both of these are from the same original.
129724223_3808444319179299_1338385097894463769_n.jpg
 
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Hi, for those who photograph smaller birds, what F stop do you use most of the time? I when doing landscapes could get the scene in focus but with these small birds if I get the eye in focus the tail is OOF shooting at F8 on a Sony A9 at around 200 to 360 on the shutter. Thanks for any advice. Russ

what is the sharp sweet spot on your lens/camera combination?
I've just started with a sigma 150-600mm and will test out the sharpest apertures to use this week.
 
despite what the pundits say, every lens/camera combo will have its own variables .. so to give a answer that works for you (the o.p) we would first have to know what your camera is and what lens your using
 
despite what the pundits say, every lens/camera combo will have its own variables .. so to give a answer that works for you (the o.p) we would first have to know what your camera is and what lens your using


Yes, Bob's excellent puffin with fish image above is shot at f7.1 on m43 , which is the equivalent of f14 on full frame, isn't it? So DoF is also dependent on sensor size.
 
Yes, Bob's excellent puffin with fish image above is shot at f7.1 on m43 , which is the equivalent of f14 on full frame, isn't it? So DoF is also dependent on sensor size.
NO it doesn't work like that . f6.3 is still the same whatever sensor you use ..if that was the case anyone using a long lens on MFT would not be able to see the bird. which is definetly not the case .. the lenses are made specifically for the size of sensor they are being used on . . which I believe also has a bearing on the thickness/width of mount adaptors for mirrorless cameras otherwise they would be wafer thin
 
Yes, Bob's excellent puffin with fish image above is shot at f7.1 on m43 , which is the equivalent of f14 on full frame, isn't it? So DoF is also dependent on sensor size.
NO it doesn't work like that . f6.3 is still the same whatever sensor you use ..
If it was at 400/7.1 on M43 it is equivalent to 800/14.2 on FF... and it is also equivalent to a 50% crop in post of a 400/7.1 FF image (in terms of DoF and light).

They would all have the same focus tolerance (depth of focus @ sensor) because they all have the same sized aperture (mm) and the same subject distance. And the equivalent enlargement (50% crop/2x FL) causes an equivalent depth of field for any given displayed image size/distance.
 
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If it was at 400/7.1 on M43 it is equivalent to 800/14.2 on FF... and it is also equivalent to a 50% crop in post of a 400/7.1 FF image (in terms of DoF and light).
the old equivalence theory again . simply doesn't make sense in any real world situation Steve ..if I use a 1.4 tc on my lens it then becomes 1160mm reach in full frame terms and following your analogy it would be f9 x 2 = f18 ...and if so you simply would have black screen to look at .. the theory doesn't fit the actual usage and simply muddles the waters with off putting ideas that dont work in real world terms
 
.if I use a 1.4 tc on my lens it then becomes 1160mm reach in full frame terms and following your analogy it would be f9 x 2 = f18
It's not an analogy... it is physics. If you place a TC on a lens it magnifies the image circle as it leaves the lens. This causes the light to be spread out farther resulting in a loss of light intensity/exposure (otherwise known as bellows factor). And it magnifies the projected details/relative sharpness, resulting in less depth of field.

If you add a 1.4x TC to an 800/5.6 lens it literally becomes an 1120/8 lens; because the TC is doing exactly the same thing as the telephoto elements do in a telephoto lens design... that's why they are called "telephoto converters." (a "telephoto" is not a long FL lens; it is an optical design where the resulting physical length of the lens is less than the focal length magnification)

The available light has a lot to do with what you can/can't see/record... I've taken pictures (video) at f/94 on FF before.

This shows the projected image circle of a 300/4 w/wo a 2x TC (with a fixed light source and flange distance)... the pencil marks are just reference for diameter.
70024835_2665024946854581_359120147107020800_n.jpg
 
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So DoF is also dependent on sensor size.

As far as I understand it, the apparent difference in DoF between crop and full frame cameras occurs when comparing shots with the same field of view. For instance, a 400mm lens used on a 1.6 crop sensor camera would give the appearance of 640mm on a FF. The DoF would be the same at these two apparently 'different' focal lengths, because it's still a 400mm lens.

To get the same field of view as using a 400mm lens on a FF camera, you'd need to use a 250mm lens on a 1.6 crop sensor camera. As a 250mm lens will give a greater DoF than a 400mm lens at the same aperture, the DoF will appear greater on a crop sensor camera when comparing it to a shot with the same field of view from a full frame camera. This is because you're shooting at 250mm on the crop sensor and 400mm on the full frame to get the same field of view.

This means that you'll get the same DoF at the 640mm equivalent on a 1.6 crop sensor as you do from a FF at 400mm, it's actually the same focal length, it's just the field of view that's been cropped, which makes a 400mm lens look like it's a 640mm one. I hope that makes sense?
 
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Well, I'm no wiser! It would be nice to have a definitive answer to this but I have a very small brain today.....
OK, I'll have another go. :)

Q. Which lens gives a deeper (more in focus) depth of field when shot with the aperture wide open (at the smallest f/ number)? A wide angle lens like a 24mm or a longer lens like a 135mm?

A. It's the wide angle lens.

Imagine if you put a 24 to 105 mm f/4 zoom lens on a full frame camera body and set it to 100mm at f/4 and took a photo (are you with me so far?).

Then you put the same zoom lens (still set to f/4) on a 1.6 crop sensor camera body, you would have to zoom out to 62.5mm to get the same 'field of view' (to frame the photo the same as the one you took with the FF camera in terms of width and height). (are you still with me there?) If so:

Q. Which focal length would give more depth of field? A wider angle 62.5mm lens, or a 100mm lens?
A. The wider angle 62.5 mm one.

This is why a crop sensor camera appears to give more depth of field at the same aperture. It's because you're actually using a shorter focal length (less mm = wider angle and more DoF) to frame the photo the same. If you kept the lens on 100mm at f/4 on both cameras, the actual DoF would remain the same, but the image would look like it had been taken with a 160mm lens on the 1.6 crop sensor camera. Does that make more sense?
 
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Imagine if you put a 24 to 105 mm f/4 zoom lens on a full frame camera body and set it to 100mm at f/4 and took a photo (are you with me so far?).

Yep!

Then you put the same zoom lens (still set to f/4) on a 1.6 crop sensor camera body, you would have to zoom out to 62.5mm to get the same 'field of view' (to frame the photo the same as the one you took with the FF camera in terms of width and height). (are you still with me there?) If so:

yes again......

This is why a crop sensor camera appears to give more depth of field at the same aperture. It's because you're actually using a shorter focal length (less mm = wider angle and more DoF) to frame the photo the same. If you kept the lens on 100mm at f/4 on both cameras, the actual DoF would remain the same, but the image would look like it had been taken with a 160mm lens on the 1.6 crop sensor camera. Does that make more sense?

I do get that, yes. :clap:
 
Q. Which focal length would give more depth of field? A wider angle 62.5mm lens, or a 100mm lens?
A. The wider angle 62.5 mm one.
You're 80% there.
If you use the same lens on a crop sensor, and back up for the same composition, which gives more DoF and why? They both have the same FoV.

In post 20 I stated that the focus tolerance (depth of focus) at the sensor is controlled only by the aperture diameter (in mm) and subject distance.
If you use a shorter focal length lens at the same f#; that is actually a smaller aperture diameter, which increases the focus tolerance. Or, if you move back to keep the composition the same, using the same lens and f#; the subject distance increases, which increases the focus tolerance.
The focus tolerance dictates how sharp things are relative to each other, as recorded by the sensor. And it is the focus tolerance that most are actually talking about when they talk about depth of field.

However, depth of field is actually a variable; and it is dependent on the magnification at which the focus tolerance is viewed...
Depth of field is your perception of acceptable sharpness. That is why a depth of field calculator uses a circle of confusion limit which is predicated on a display size and viewing distance (standard viewing conditions by a person w/ average eyesight).
Anything that increases the magnification of the focus tolerance reduces the perceived depth of field... that can be lens magnification, it can be cropping and enlarging (sensor/post), or more critical viewing from a shorter distance. All of those things are really just different versions of cropping/magnifying the scene/light.

Take an image of marginal sharpness and display it on your monitor so that the flaws are apparent. Now make it smaller so that the flaws are not apparent... it looks sharper. Now make it larger again to where it looks bad, then get up and move a distance away to where the flaws are not apparent again... it looks sharper again. THAT is depth of field in practice... while the recorded focus tolerance/depth of focus has remained constant.


How aperture diameter affects focus tolerance/depth of focus (the narrow aperture rays are also inside of the wide aperture; just not depicted for simplicity/clarity)
85100299_3001191829904556_3941081494256091136_n.jpg
 
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You're 80% there.
If you use the same lens on a crop sensor, and back up for the same composition, which gives more DoF and why? They both have the same FoV.

In post 20 I stated that the focus tolerance (depth of focus) at the sensor is controlled only by the aperture diameter (in mm) and subject distance.
If you use a shorter focal length lens at the same f#; that is actually a smaller aperture diameter, which increases the focus tolerance. Or, if you move back to keep the composition the same, using the same lens and f#; the subject distance increases, which increases the focus tolerance.
The focus tolerance dictates how sharp things are relative to each other, as recorded by the sensor. And it is the focus tolerance that most are actually talking about when they talk about depth of field.

However, depth of field is actually a variable; and it is dependent on the magnification at which the focus tolerance is viewed...
Depth of field is your perception of acceptable sharpness. That is why a depth of field calculator uses a circle of confusion limit which is predicated on a display size and viewing distance (standard viewing conditions by a person w/ average eyesight).
Anything that increases the magnification of the focus tolerance reduces the perceived depth of field... that can be lens magnification, it can be cropping and enlarging (sensor/post), or more critical viewing from a shorter distance. All of those things are really just different versions of cropping/magnifying the scene/light.

Take an image of marginal sharpness and display it on your monitor so that the flaws are apparent. Now make it smaller so that the flaws are not apparent... it looks sharper. Now make it larger again to where it looks bad, then get up and move a distance away to where the flaws are not apparent again... it looks sharper again. THAT is depth of field in practice... while the recorded focus tolerance/depth of focus has remained constant.


How aperture diameter affects focus tolerance/depth of focus (the narrow aperture rays are also inside of the wide aperture; just not depicted for simplicity/clarity)
View attachment 312263
And tomorrow night's task is to explain to us all, in 3 colours or less, exactly how a tilt shift lens works. ;) :exit:
 
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