Dan,
Thank you, yes I was. I have had another play and referred to the manual. That will be another improvement no doubt.
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K1 AF-C looks like a winner ........
- Thread starter robbo d
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Thank you, yes I was. I have had another play and referred to the manual. That will be another improvement no doubt.
MightyMike
Forum Pro
Please Re-Do these tables for the same subject framing as in the end its the same result we're after not 50% more out of focus area around the subject
So APS-C at 10ft, FF at 6.67ft what are the DOF differences then?
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Mike from Canada
"I am not a great photographer! God is a great creator! All I do is capture His creation with the tools He has provided me."
'I like to think so far outside the box that it would require a telephoto lens just to see the box!' ~ 'My Quote
'
www.airliners.net
So APS-C at 10ft, FF at 6.67ft what are the DOF differences then?
It is a very common mistake, repeated everywhere, and many reviewers too are just rambling without real understanding. "Shallower DoF" is used as a misnomer for "more blurry DoF to OoF transition". While in fact, FF camera has more DoF — total space in front and in the back of the subject available to achieve acceptable focus. That is 50% more room for error. Therefore correct wording should be (using same parameters as per table below):
FF has deeper DoF,
FF produces OoF transition with less details
FF allows more room for focusing errors
APS-C has shallower DoF,
APS-C produces OoF transition with more details
APS-C allows little room for focusing error
Conclusion: APS-C cameras are more difficult to master.
See this image from the DoF Calculator. Using same lens and same aperture, at the same distance an FF camera yields 50% more DoF. That is significant, and that means, you have 50% more chances to get a keeper.
Nothing was wrong with Pentax AF or its precision all these years; but Pentax needed an FF camera to show many people they don't understand at all ...
--
Madamina, il catalogo è questo; Delle belle che amò il padron mio; un catalogo egli è che ho fatt'io; Osservate, leggete con me.
--
Mike from Canada
"I am not a great photographer! God is a great creator! All I do is capture His creation with the tools He has provided me."
'I like to think so far outside the box that it would require a telephoto lens just to see the box!' ~ 'My Quote
'Aviation Photo Search | Airliners.net
www.airliners.net
MightyMike
Forum Pro
What if people don't want 50% more FOV??? matching subject framing! its perfectly acceptable.
Not for photos i take, and when it comes to airshows i just use a longer lens.
Its not miraculously fixed, its more definite about obtaining its lock but not fixed, it still have its quirks
petebfrance
Leading Member
Or, looking at it another way, do it at the same distance to get the same framing i.e. the equivalent aperture on the APSC to that used on the FF. 1.5, I think, so it should be FF 55mm versus APSC 36.666666 (oh well, say 37) mm on APSC. If the original proposal were correct it would be a miracle if I got anything in focus on my 1/2.5" sensor bridge camera. Nice, though, it really woke me up....Please Re-Do these tables for the same subject framing as in the end its the same result we're after not 50% more out of focus area around the subject
So APS-C at 10ft, FF at 6.67ft what are the DOF differences then?
--It is a very common mistake, repeated everywhere, and many reviewers too are just rambling without real understanding. "Shallower DoF" is used as a misnomer for "more blurry DoF to OoF transition". While in fact, FF camera has more DoF — total space in front and in the back of the subject available to achieve acceptable focus. That is 50% more room for error. Therefore correct wording should be (using same parameters as per table below):
FF has deeper DoF,
FF produces OoF transition with less details
FF allows more room for focusing errors
APS-C has shallower DoF,
APS-C produces OoF transition with more details
APS-C allows little room for focusing error
Conclusion: APS-C cameras are more difficult to master.
See this image from the DoF Calculator. Using same lens and same aperture, at the same distance an FF camera yields 50% more DoF. That is significant, and that means, you have 50% more chances to get a keeper.
Nothing was wrong with Pentax AF or its precision all these years; but Pentax needed an FF camera to show many people they don't understand at all ...
--
Madamina, il catalogo è questo; Delle belle che amò il padron mio; un catalogo egli è che ho fatt'io; Osservate, leggete con me.
Mike from Canada
"I am not a great photographer! God is a great creator! All I do is capture His creation with the tools He has provided me."
'I like to think so far outside the box that it would require a telephoto lens just to see the box!' ~ 'My Quote
http://www.michaelfastphotography.com/galleries/VP-BDI_3a.jpg
http://www.airliners.net/search/[email protected]&thumbnails=
audiobomber
Veteran Member
ozdean
Forum Pro
But Zvonimir if you are at the same distance your framing will be totally different.
Take a shot in FF mode then take it in crop mode - totally different framing!
I repeat the only thing that changes dof is aperture when using cameras with the same registration distance.
Even if you go from a 50mm lens on the same camera to a 100mm lens at the same aperture because you need to stand back twice as far to get identical framing the dof will be the same - it is directly proportional to the focal length.
Now if we put the same lens on the Q the dof increases and if we put it on the 645 it decreases because of registration distance.
That's why MF has that different look ie perspective.
Take a shot in FF mode then take it in crop mode - totally different framing!
I repeat the only thing that changes dof is aperture when using cameras with the same registration distance.
Even if you go from a 50mm lens on the same camera to a 100mm lens at the same aperture because you need to stand back twice as far to get identical framing the dof will be the same - it is directly proportional to the focal length.
Now if we put the same lens on the Q the dof increases and if we put it on the 645 it decreases because of registration distance.
That's why MF has that different look ie perspective.
ozdean
Forum Pro
The real advantage of FF is in the bokeh for the likes of portraiture & studio where you are working at a close set distance.
On APSC you will use a 55 - wider angle of view so busier background = less pleasing bokeh
ON FF you will use 55 x 1.5 = 82.5 (85) narrower angle of view smaller back ground = more pleasing bokeh
If you could use an 82.5, dof will be the same but bokeh better because it is a less busy background which always gives a more pleasing bokeh.
Note I have used 1.5 as the crop factor but I think it is actually slightly less than that.
On APSC you will use a 55 - wider angle of view so busier background = less pleasing bokeh
ON FF you will use 55 x 1.5 = 82.5 (85) narrower angle of view smaller back ground = more pleasing bokeh
If you could use an 82.5, dof will be the same but bokeh better because it is a less busy background which always gives a more pleasing bokeh.
Note I have used 1.5 as the crop factor but I think it is actually slightly less than that.
12HT75
Well-known member
12HT75
Well-known member
Thank you for these examples Zvonimir, that helps also.It is a very common mistake, repeated everywhere, and many reviewers too are just rambling without real understanding. "Shallower DoF" is used as a misnomer for "more blurry DoF to OoF transition". While in fact, FF camera has more DoF — total space in front and in the back of the subject available to achieve acceptable focus. That is 50% more room for error. Therefore correct wording should be (using same parameters as per table below):
FF has deeper DoF,
FF produces OoF transition with less details
FF allows more room for focusing errors
APS-C has shallower DoF,
APS-C produces OoF transition with more details
APS-C allows little room for focusing error
Conclusion: APS-C cameras are more difficult to master.
See this image from the DoF Calculator. Using same lens and same aperture, at the same distance an FF camera yields 50% more DoF. That is significant, and that means, you have 50% more chances to get a keeper.
Nothing was wrong with Pentax AF or its precision all these years; but Pentax needed an FF camera to show many people they don't understand at all ...
--
Madamina, il catalogo è questo; Delle belle che amò il padron mio; un catalogo egli è che ho fatt'io; Osservate, leggete con me.
--
Peter.
audiobomber
Veteran Member
DOF changes with focal length, position and aperture. These are the only parameters one needs to enter in a DOF calculator. Registration distance is irrelevant.
I'll copy and paste from a previous post because starting over is too much work:
Equivalence for a lens means same DOF, same FOV, same noise, same diffraction, same perspective. Perspective is dependent on subject distance, so keep it the same for each system. Adjust focal length and f-number by the crop factor. Use ISO to equalize brightness. Here are a few equivalents:
Nikon V1, 1" sensor, 100mm f/2.0, crop factor 2.7X
@ 10 ft. subject distance, DOF is 0.13 ft.
@ 100 ft. subject distance, DOF is 13.4 ft.
Pentax K-50 APS-C sensor, 180mm f/3.6, crop factor 1.5X
@ 10 ft. subject distance, DOF is 0.13 ft.
@ 100 ft. subject distance, DOF is 13.4 ft.
Nikon D800, FF sensor, 270mm f/5.6, crop factor 1X
@ 10 ft. subject distance, DOF is 0.13 ft.
@ 100 ft. subject distance, DOF is 14.1 ft. (The DOF calculator would not allow f5.4, which explains the slight difference in DOF at 100 feet).
http://www.dofmaster.com/dofjs.html
Now let's look at noise equivalence using DXOMark:
Nikon V1, 100mm, 1/300s, f/2.0, ISO 100; SNR is ~35dB
Pentax K-50, 180mm, 1/300s, f/3.6, ISO 350; SNR ~35dB
Nikon D800, 270mm, 1/300s, f5.6, ISO 640; SNR ~35dB
Nikon D800 versus Pentax K-50 versus Nikon 1 V1 - Side by side camera comparison - DxOMark
In summary, photos taken with the above setups will be equivalent in FOV, DOF, perspective, diffraction and noise, i.e. equivalent photos.
I could show the same equivalence with Medium Frame given sufficient data. (Neither the DOF calculator nor DXO show data for MF). For equivalence to the above on a 645Z (0.79 crop), you would need a 340mm lens at f6.8.
--
Dan
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