I made this instrument with the use of the information available here.
The 1.st picture is one side
The 2.ed picture is from the other side.
The 3.ed picture is the demonstration of how to use it.
I have seen something similar somewhere in the net.
But it was so small I could not see it properlly.
How do you like this ?
It should/can be used in conjunction with this table
These "instruments" are for my lenses.
You can see the originals at: http://antoniocorreia.smugmug.com/gallery/1708250/1/86066459
Thank for watching and commenting.
digital cameras with a format smaller than 35mm, i.e. aps-c or 1.6x crop - will have MORE depth of field than a larger sensor. which is why the 5d can give you less DOF at the same aperture as a 20d or 30d or nikon dxx.
He actually hasn't contradicted my statements. Mr. Reichmann says *low-end* digital cameras have greater DOF but not because they're digital but because the lens is so small:
If those small-format cameras had a long lens like those used in a 35 mm SLR they would end up with less DOF.[/left]
Erich
that is simply not the case. it has nothing to do with the lens. it has to do with the sensor size.
of course a longer lens will give less DOF but we are talking about sensor size here with the equivalent lens/f stop.
this is definitely one of the reasons i want a 5d or FF camera.
Erich, I hope you don't mind that I keep posting here about DOF. Obrigado.
I made today the chart herewith.
You may ask: what for ? There's no use for it.
And may be you are right.
But let me explain what I had in mind.
The depth of field tables are usefull but are difficult to work with when the distances are too big.
I have written about this problem on Nikolai's assignment and my difficulties...
The table is to show the photographer, using 16 mm to 35 mm lens, where the DF is when focusing on the hyperfocal distance.
The look at this table gives a quick glance of the DOF under different apertures.
It's far easiest to estimate that the object is 4 or 6 meters away than 200 m and the quick look to the table tell us that, using an aperture under 8, we will have all in focus.
Am I messing up and making things more complicated that they are ?
The expoaperture disc will help you calculate DOF etc for different lenses etc in a single gadget
Seems to be pretty good so far in the tests I have carried out. The manual is available online so you can see how it works
Andy
A Brit among the HAWKEYES Canon 5D Mk III Canon 24-105L IS USM; Canon 16-35 f/2.8L USM; Canon 70-200 f/2.8L IS USM II Sigma 150mm f/2.8 EX DG HSM; Bigma 50-500 f/4-6.3 EX DG HSM My Galleries
Andy,
Have a look at my post here .
I made the expo disk myself !
It was agood ideia to post that link here..
Kudos for doing all that work!
I have made similar calculators to the one you showed here, using the DOFMater program, but I like the Expo one more as it is simple to use for pretty much all focal lengths
Admittedly there is some tweaking required to use with a non full frame DSLR but they tell you how to do it in the manual and it is pretty easy to do in the field
A Brit among the HAWKEYES Canon 5D Mk III Canon 24-105L IS USM; Canon 16-35 f/2.8L USM; Canon 70-200 f/2.8L IS USM II Sigma 150mm f/2.8 EX DG HSM; Bigma 50-500 f/4-6.3 EX DG HSM My Galleries
that is simply not the case. it has nothing to do with the lens. it has to do with the sensor size.
Mr. Reichmann statement is correct :
Cameras with smaller sensor do not have long lenses
But maybe it could be worded a little better: a long lens (meaning lens with long focal length) yield impractical fields of view in combination with a small sensor: too small for a camera sold to a wide audience. Therefore manufacturers use short lenses in their P&S cameras. When these lenses are used at typical FOV equivalent to 50 mm on a 35 mm camera, they are actually using 15 mm (say, size of sensors in P&S cameras are not all the same) focal length (that's wide-angle!).
The effect of the sensor size itself goes the other way: smaller sensor needs means smaller circle of confusion which implies smaller (not larger) DOF for same focal length. However the impact is proportional to sensor size. By contrast the impact of focal length on DOF is inversely proportional to the square (for most situations) of focal length. As a result for a same field of view captured with sensor of different sizes, the effect coming from the shorter focal length "wins", hence camera with the smaller sensor will have wider DOF.
The difference between FF and APS-C is small enough that it can be handled with a small aperture adjustement in most shooting situations. Most people who buy a 5D would be better served buying a 30D, save the money for better glass (which will also opens wider), and invest in a $50 book on the basics of photography. One has just to peruse the EXIF data of the 5D pics posted in dpreview forum to get an idea of what I'm talking about.
that is simply not the case. it has nothing to do with the lens. it has to do with the sensor size.
of course a longer lens will give less DOF but we are talking about sensor size here with the equivalent lens/f stop.
this is definitely one of the reasons i want a 5d or FF camera.
You are partly correct.
I used "small lens" incorrectly here. I meant "small" in terms of focal length, not aperture (this was early on when I was still sorting through all this...the right terminology is "short").
It is the focal length which determines perspective. The size of the focal plane just determines FOV and what crop you get. That said, for an equivalent FOV, a smaller focal plane requires a shorter focal length than a larger focal plane. Therefore, small focal planes tend to be paired up with *short* focal length lens. That's what creates the increased DOF.
If you take the same lens at the same aperture and put it in front of a 5D you'll just get a bigger FOV than with a 20D. The DOF will be the same all else being equal. But not all else is equal because I think the 5D's pixels are larger than the 20D's. I think larger pixels give you more "depth-of-focus" because you are not as sensitive to changes in the optical focus.
Cameras with smaller sensor do not have long lenses
But maybe it could be worded a little better: a long lens (meaning lens with long focal length) yield impractical fields of view in combination with a small sensor: too small for a camera sold to a wide audience. Therefore manufacturers use short lenses in their P&S cameras. When these lenses are used at typical FOV equivalent to 50 mm on a 35 mm camera, they are actually using 15 mm (say, size of sensors in P&S cameras are not all the same) focal length (that's wide-angle!).
The effect of the sensor size itself goes the other way: smaller sensor needs means smaller circle of confusion which implies smaller (not larger) DOF for same focal length. However the impact is proportional to sensor size. By contrast the impact of focal length on DOF is inversely proportional to the square (for most situations) of focal length. As a result for a same field of view captured with sensor of different sizes, the effect coming from the shorter focal length "wins", hence camera with the smaller sensor will have wider DOF.
The difference between FF and APS-C is small enough that it can be handled with a small aperture adjustement in most shooting situations. Most people who buy a 5D would be better served buying a 30D, save the money for better glass (which will also opens wider), and invest in a $50 book on the basics of photography. One has just to peruse the EXIF data of the 5D pics posted in dpreview forum to get an idea of what I'm talking about.
Comments
The 1.st picture is one side
The 2.ed picture is from the other side.
The 3.ed picture is the demonstration of how to use it.
I have seen something similar somewhere in the net.
But it was so small I could not see it properlly.
How do you like this ?
It should/can be used in conjunction with this table
These "instruments" are for my lenses.
You can see the originals at:
http://antoniocorreia.smugmug.com/gallery/1708250/1/86066459
Thank for watching and commenting.
Gear
*Canon 40D: 17-55IS - 70-300IS - 100mm Macro - Sigma 10-20EX
*Imagination
of course a longer lens will give less DOF but we are talking about sensor size here with the equivalent lens/f stop.
this is definitely one of the reasons i want a 5d or FF camera.
Gear
*Canon 40D: 17-55IS - 70-300IS - 100mm Macro - Sigma 10-20EX
*Imagination
I made today the chart herewith.
You may ask: what for ? There's no use for it.
And may be you are right.
But let me explain what I had in mind.
The depth of field tables are usefull but are difficult to work with when the distances are too big.
I have written about this problem on Nikolai's assignment and my difficulties...
The table is to show the photographer, using 16 mm to 35 mm lens, where the DF is when focusing on the hyperfocal distance.
The look at this table gives a quick glance of the DOF under different apertures.
It's far easiest to estimate that the object is 4 or 6 meters away than 200 m and the quick look to the table tell us that, using an aperture under 8, we will have all in focus.
Am I messing up and making things more complicated that they are ?
I posted about this in the Gadgets forum but it bears montioning here as well
Check out http://www.expodisc.com/products/product_detail.php?prodid=4&productname=ExpoAperture_Depth_of_Field_Guide
The expoaperture disc will help you calculate DOF etc for different lenses etc in a single gadget
Seems to be pretty good so far in the tests I have carried out. The manual is available online so you can see how it works
Andy
Canon 5D Mk III
Canon 24-105L IS USM; Canon 16-35 f/2.8L USM; Canon 70-200 f/2.8L IS USM II
Sigma 150mm f/2.8 EX DG HSM; Bigma 50-500 f/4-6.3 EX DG HSM
My Galleries
Have a look at my post here .
I made the expo disk myself !
It was agood ideia to post that link here..
Kudos for doing all that work!
I have made similar calculators to the one you showed here, using the DOFMater program, but I like the Expo one more as it is simple to use for pretty much all focal lengths
Admittedly there is some tweaking required to use with a non full frame DSLR but they tell you how to do it in the manual and it is pretty easy to do in the field
Canon 5D Mk III
Canon 24-105L IS USM; Canon 16-35 f/2.8L USM; Canon 70-200 f/2.8L IS USM II
Sigma 150mm f/2.8 EX DG HSM; Bigma 50-500 f/4-6.3 EX DG HSM
My Galleries
Mr. Reichmann statement is correct :
Cameras with smaller sensor do not have long lenses
But maybe it could be worded a little better: a long lens (meaning lens with long focal length) yield impractical fields of view in combination with a small sensor: too small for a camera sold to a wide audience. Therefore manufacturers use short lenses in their P&S cameras. When these lenses are used at typical FOV equivalent to 50 mm on a 35 mm camera, they are actually using 15 mm (say, size of sensors in P&S cameras are not all the same) focal length (that's wide-angle!).
The effect of the sensor size itself goes the other way: smaller sensor needs means smaller circle of confusion which implies smaller (not larger) DOF for same focal length. However the impact is proportional to sensor size. By contrast the impact of focal length on DOF is inversely proportional to the square (for most situations) of focal length. As a result for a same field of view captured with sensor of different sizes, the effect coming from the shorter focal length "wins", hence camera with the smaller sensor will have wider DOF.
The difference between FF and APS-C is small enough that it can be handled with a small aperture adjustement in most shooting situations. Most people who buy a 5D would be better served buying a 30D, save the money for better glass (which will also opens wider), and invest in a $50 book on the basics of photography. One has just to peruse the EXIF data of the 5D pics posted in dpreview forum to get an idea of what I'm talking about.
Thierry
You are partly correct.
I used "small lens" incorrectly here. I meant "small" in terms of focal length, not aperture (this was early on when I was still sorting through all this...the right terminology is "short").
It is the focal length which determines perspective. The size of the focal plane just determines FOV and what crop you get. That said, for an equivalent FOV, a smaller focal plane requires a shorter focal length than a larger focal plane. Therefore, small focal planes tend to be paired up with *short* focal length lens. That's what creates the increased DOF.
If you take the same lens at the same aperture and put it in front of a 5D you'll just get a bigger FOV than with a 20D. The DOF will be the same all else being equal. But not all else is equal because I think the 5D's pixels are larger than the 20D's. I think larger pixels give you more "depth-of-focus" because you are not as sensitive to changes in the optical focus.
Erich
I don't mind at all! IT's entirely appropriate. This is not *my* thread after all. It's the forum!
Cheers,
Erich