Ricoh predicts DSLRs will bounce back

Michael Clark

Now we see through a glass, darkly...
Apr 5, 2016
1,139
570
Sales are going to be the driving force and where R&D will be positioned. Pentax is in a state a denial. If people switch entirely to mirrorless, I can't seem them transitioning back normally. The statement reminds me of a Kodak moment and we know where they went. I agree both have their strengths and weaknesses but I cannot see the shift back to just DSLR's anymore. Hopefully they will harmonize.
The prediction is not that everyone will switch back to just DSLRs and mirrorless will die out. It is that some or many will switch back once the novelty of mirrorless has worn off. For some use cases mirrorless has advantages. For some use cases DSLRs have advantages. The observation is that not everyone will permanently switch to mirrorless.
 

Rocky

EOS 6D MK II
Jul 30, 2010
918
32
News flash - DoF is dependent upon only two things: aperture and magnification.

Magnification is affected by the following:

Subject distance
Focal length of the lens
Enlargement ratio from the size of the image projected onto the sensor to the size of the image as displayed when viewed
The distance between the image and the viewer

If you take the exact same image, display it at both 8x10 and 16x20, and view both from the same distance the larger display size will have narrower DoF than the smaller display size. Why? Because as one enlarges an image one enlarges all of the blur in that image. Viewed at the same distance, the viewer's eye can discriminate blur more easily in the larger display size.

Or if you take the same exact display size and view it at different distances the DoF will change. As one gets further away from the image, the apparent DoF will increase as it takes a larger and larger blur radius to be perceived as blur instead of a point.
Thanks Mike, what you are talking about is the perception of sharpness and the human eye. Not the original definition of DOF in the film day. Kit and I are talking about DOF in film cametas
 

3kramd5

EOS 5D MK IV
Mar 2, 2012
3,083
404
I do not post any threshold. I just quote an example. A good film rangefinder is guaranteed to be accurate to 135 f4. The same system will be very accurate for 50mm or shorter. In fact I have used the system down to 50 f0.95 and still accurate
You said, “A good Film rangefinder WILL focus much better than film DSLR for focal length shorter than 50mm”

I said “That sounds arbitrary,” which you took issue with.

Now you say you just posted an example.

FYI, arbitrary = Determined by chance, whim, or impulse, and not by necessity, reason, or principle. That seems to appropriately describe how you chose to say 50mm.
 

Kit.

EOS 6D MK II
Apr 25, 2011
1,417
792
You cannot tell me , because you do not know.
In fact, I do. For a circle of confusion C, magnification M and F-number N (effective F-number for macro), if we are far from the hyperfocal distance, DOF is roughly equal to 2CN/M²

That's why rangefinders suck at closeups and even some portraits. That's why Leica was producing Mirror Reflect Housing, and later Visoflex adapters, effectively turning a rangefinder camera into a poor version of SLR. A ragefinder focusing is just not precise enough to work with relatively high magnifications.

So far you have not explain anything to me.
So far, you haven't shown any willingness to learn. You are just baselessly claiming that you have some sacred knowledge and posting statements that are both banal and inaccurate.
 

Michael Clark

Now we see through a glass, darkly...
Apr 5, 2016
1,139
570
Thanks Mike, what you are talking about is the perception of sharpness and the human eye. Not the original definition of DOF in the film day. Kit and I are talking about DOF in film cametas
DoF in film cameras is based on the unspoken assumptions of:

  • A 36x24 mm imaging area (usually cropped to about 95% when printed to avoid the rough edges)
  • A further crop along the long axis to produce a 5:4 aspect ratio
  • Enlargement to an 8x10 inch print
  • A viewing distance of 10-12 inches
  • A viewer with 20/20 vision (unless you were Zeiss, who assumed a viewer with 20/15 vision and thus used a circle of confusion of 0.25mm instead of 0.3mm like everyone else)
DoF is always about human perception. There is only one focus distance that is in sharpest focus. Everything else is blurrier to some extent. DoF is a way of defining how much blur is allowable that still looks, to human eyes, like it is in focus.

Back in the film days, we knew if we planned to print at, say, 16x20 (which is twice the linear dimensions of 8x10) we needed to account for that when we shot by doubling the f-numbers on the lens' DoF scale!
 
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Rocky

EOS 6D MK II
Jul 30, 2010
918
32
DoF in film cameras is based on the unspoken assumptions of:

  • A 36x24 mm imaging area (usually cropped to about 95% when printed to avoid the rough edges)
  • A further crop along the long axis to produce a 5:4 aspect ratio
  • Enlargement to an 8x10 inch print
  • A viewing distance of 10-12 inches
  • A viewer with 20/20 vision (unless you were Zeiss, who assumed a viewer with 20/15 vision and thus used a circle of confusion of 0.25mm instead of 0.3mm like everyone else)
DoF is always about human perception. There is only one focus distance that is in sharpest focus. Everything else is blurrier to some extent. DoF is a way of defining how much blur is allowable that still looks, to human eyes, like it is in focus.

Back in the film days, we knew if we planned to print at, say, 16x20 (which is twice the linear dimensions of 8x10) we needed to account for that when we shot by doubling the f-numbers on the lens' DoF scale!
Please go dig up the DOF calculation formula. Magnification is never in the equation. You even said it yourself that if you want to make larger than 8X10, you will override the DOF scale on the lens. Also the circle of confusion is 0.03mm for 35mm film except Leica uses 0.02mm to calculate the DOF for their lenses.
Most of your "unspoken assumption" are actually used in the DOF calculation formula. Except the circle of confusion is shifted by a factor of 10. MAGNIFICATION is never in the calculation formula.
 

Rocky

EOS 6D MK II
Jul 30, 2010
918
32
In fact, I do. For a circle of confusion C, magnification M and F-number N (effective F-number for macro), if we are far from the hyperfocal distance, DOF is roughly equal to 2CN/M²

That's why rangefinders suck at closeups and even some portraits. That's why Leica was producing Mirror Reflect Housing, and later Visoflex adapters, effectively turning a rangefinder camera into a poor version of SLR. A ragefinder focusing is just not precise enough to work with relatively high magnifications.


So far, you haven't shown any willingness to learn. You are just baselessly claiming that you have some sacred knowledge and posting statements that are both banal and inaccurate.
No need for personal attack here. I have never claim any sacred knowledge as you claimed. All my statements are accurate(may be beyond your understanding??). We started out with focusing between rangefinder and DSLR film camera( assuming within in the capacity of both cameras) Then you keep on changing and get tilt-shift lens involved. . Now it is MACRO photography. You should know that rangefinder camera are not built for these task. Just go dig up the DOF formula for normal photography, It only involve focal length of the lens, aperture, and circle of confusion. There is no magnification involved.
Since you started personal attack, that is the end of this discussion in order to keep this website being civilize. Just be cool and keep calm and take some tranquilizer.
 

Rocky

EOS 6D MK II
Jul 30, 2010
918
32
You said, “A good Film rangefinder WILL focus much better than film DSLR for focal length shorter than 50mm”

I said “That sounds arbitrary,” which you took issue with.

Now you say you just posted an example.

FYI, arbitrary = Determined by chance, whim, or impulse, and not by necessity, reason, or principle. That seems to appropriately describe how you chose to say 50mm.
You are RIGHT. I impulsively bought the Leica M4 (too expensive), not by necessity, to use parallel with my other SLR. ( I arbitrarily not to mention the made or the model) I bought 35mm, 50mm for both system. got 135mm ( for flowers and close up) for the SLR and 90mm (for portrait),. I compare the focusing ability for both 35mm and 50mm only in both system, and draw the conclusion by my own personal experience, not by principle. No comparison for 90mm and 135mm, that is incomplete and whim. I cannot compare the 90mm and 135mm because I do not have them on both system by chance. So I draw conclusion for 50mm and 35mm .it is unreasonable.
SO everything fits the ARBITRARY.
Just for my education., which rangefinder film camera have you used
 

3kramd5

EOS 5D MK IV
Mar 2, 2012
3,083
404
Please go dig up the DOF calculation formula. Magnification is never in the equation.
Of course it is; it’s a factor in the circle of confusion, which is used to compute far and near limits of acceptable focus, the difference if which is DOF.
 
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Kit.

EOS 6D MK II
Apr 25, 2011
1,417
792
No need for personal attack here.
You started personal attacks here, by absolutely baselessly claiming that I don't know what DOF is.

I have never claim any sacred knowledge as you claimed.
"If you have ever use a Leica rangefinder film camera. you will understand " - is a claim of sacred knowledge.

All my statements are accurate(may be beyond your understanding??). We started out with focusing between rangefinder and DSLR film camera( assuming within in the capacity of both cameras) Then you keep on changing and get tilt-shift lens involved.
Your statement “A good Film rangefinder WILL focus much better than film DSLR for focal length shorter than 50mm” was inaccurate. First, it mentioned some "film DSLR". Then, your statement is completely wrong for the only lens fully shorter than 50mm that I use regularly: my TS-E 17.

Now it is MACRO photography. You should know that rangefinder camera are not built for these task.
If you shoot near hyperfocal distance, you don't need good focusing. Basically, you are claiming "a good film rangefinder will focus better than SLR when you don't need good focusing".

Just go dig up the DOF formula for normal photography, It only involve focal length of the lens, aperture, and circle of confusion. There is no magnification involved.
Of course magnification can be easily found there. For non-macro photography, magnification is a ratio of focal length to focus distance.
 

Michael Clark

Now we see through a glass, darkly...
Apr 5, 2016
1,139
570
Please go dig up the DOF calculation formula. Magnification is never in the equation. You even said it yourself that if you want to make larger than 8X10, you will override the DOF scale on the lens. Also the circle of confusion is 0.03mm for 35mm film except Leica uses 0.02mm to calculate the DOF for their lenses.
Most of your "unspoken assumption" are actually used in the DOF calculation formula. Except the circle of confusion is shifted by a factor of 10. MAGNIFICATION is never in the calculation formula.
OK, so it was late and I dropped a decimal place. My mistake.

It's still all about aperture and magnification. The only factor in the DoF formula that isn't about magnification is the aperture expressed as an f-number. Everything else in that formula is directly related to magnification: that is, how many degrees-minutes-seconds of arc the subject occupies in the viewer's field of view.

Although the CoC is expressed as a linear measurement on the imaging sensor or film, it is determined by the angular measurement of the largest blur circle that the viewer can be expected to perceive as a point with an assumed display size and viewing distance. When we use a CoC of 0.03mm with 135 format film, it is based on the assumption of an enlargement ratio to an 8x10 image that will be viewed by a person with 20/20 vision from a distance of one foot. If we use the metric "standard" of 10cm viewing distance, the CoC drops to 0.025mm because the viewer is proportionally closer to the image by the same proportion as that between 0.03 and 0.025.¹ If we change the viewing distance to two feet, the CoC grows to 0.06mm. If we change the display size to 16x20 and still view it from one foot, the CoC shrinks to 0.015. If we view the 16x20 image from two feet, the CoC is again 0.03. In every single case, the CoC is based on the exact same angular size of the largest amount of blur that will be perceived as a point by the viewer.

¹ The ratio between 0.03 and 0.025 is 1.2:1. The ratio between 12 inches (30.48cm) and 25cm is 1.2192:1.

Total magnification is defined as the relative angular size of the actual subject as measured from the camera compared to the angular size of the subject in the viewed image as seen by the viewer. As stated earlier, factors that influence magnification:
- Subject distance
- Focal length
- Enlargement ratio
- Viewing distance
 
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Michael Clark

Now we see through a glass, darkly...
Apr 5, 2016
1,139
570
No need for personal attack here. I have never claim any sacred knowledge as you claimed. All my statements are accurate(may be beyond your understanding??). We started out with focusing between rangefinder and DSLR film camera( assuming within in the capacity of both cameras) Then you keep on changing and get tilt-shift lens involved. . Now it is MACRO photography. You should know that rangefinder camera are not built for these task. Just go dig up the DOF formula for normal photography, It only involve focal length of the lens, aperture, and circle of confusion. There is no magnification involved.
Since you started personal attack, that is the end of this discussion in order to keep this website being civilize. Just be cool and keep calm and take some tranquilizer.
Focal length is an expression of magnification! That's what a lens does when it refracts light! It magnifies it! For most lenses, the magnification factor is less than 1.0, but if an image of the subject on the sensor/film is one half the size of the actual subject, then the magnification ratio is 1:2 or 0.5X. That's still a magnification factor.

The DoF formula also includes subject distance in addition to focal length, aperture, and CoC. This is because subject distance also affects magnification!

If a lens has a reproduction ratio (i.e. magnification) of 1:1 at a MFD that is equal to 4X the focal length - at "unity" a single element thin lens with 100mm focal length (as measured when focused at infinity) is 200mm from the imaging plane and the subject is another 200mm beyond the lens, or 400mm from the imaging plane - the size of the subject as projected onto the imaging plane will equal the the size of the subject. Both the subject and the virtual image of the subject will have the same angular size as measured from the lens. If the subject is moved further away from the camera and the lens is moved closer to the imaging plane to bring the subject into focus, the size of the subject is reduced in the virtual image. That is, the virtual image of the subject is now smaller than the actual size of the subject because both are still the same angular size as measured from the lens but the lens is much closer to the imaging plane (sensor/film) than to the subject.

For example, when we take a 300m lens and fill the long side of a 35mm/FF with a person 6 foot (1.829m or 1829mm) tall standing at a distance of 49 feet 9 inches from the camera's imaging plane, the magnification ratio is 35mm/1829mm, or 1:52.25 for a magnification ratio of 0.019X. This occurs because both the subject and the virtual image of the subject projected onto the the camera's imaging plane (film/sensor) have an angular size of 6.9° as measured from 300mm in front of the camera's imaging plane.

From wikipedia:

Magnification is the process of enlarging the apparent size, not physical size, of something. This enlargement is quantified by a calculated number also called "magnification". When this number is less than one, it refers to a reduction in size, sometimes called minification or de-magnification.
Also from wikipedia:

The angular diameter, angular size, apparent diameter, or apparent size is an angular measurement describing how large a sphere or circle appears from a given point of view.
Everything about DoF is based upon the angular size, as measured by the viewer's eyes, of the largest blur circle that will not be distinguishable from a single point.
 

Tugela

EOS 6D MK II
Feb 12, 2014
855
13
The prediction is not that everyone will switch back to just DSLRs and mirrorless will die out. It is that some or many will switch back once the novelty of mirrorless has worn off. For some use cases mirrorless has advantages. For some use cases DSLRs have advantages. The observation is that not everyone will permanently switch to mirrorless.
The advantages of the DSLR will disappear fairly quickly though, but the disadvantages will remain. It is hard to see people going back. Ricoh are delusional on this one. They clearly do not understand how the market is evolving and it is going to leave them flatfooted at the exit door like Kodak.
 

Michael Clark

Now we see through a glass, darkly...
Apr 5, 2016
1,139
570
The advantages of the DSLR will disappear fairly quickly though, but the disadvantages will remain. It is hard to see people going back. Ricoh are delusional on this one. They clearly do not understand how the market is evolving and it is going to leave them flatfooted at the exit door like Kodak.
Until someone invents an EVF that requires no battery power, cameras with OVFs will continue to have at least one advantage over those with only EVFs.
 

neuroanatomist

I post too Much on Here!!
Jul 21, 2010
24,619
2,105
Just go dig up the DOF formula for normal photography, It only involve focal length of the lens, aperture, and circle of confusion. There is no magnification involved.
Sorry, Rocky – no pulling a rabbit out of the hat for you. Bullwinkle says DoF is determined by only two factors – aperture (the apparent size of the iris diaphragm) and magnification. We replace magnification by focal length and subject distance for convenience when estimating DoF because we can determine those factors pretty easily, whereas measuring magnification is not simple, since it's determined by the size of a subject in object space (the real world), image space (subject projected onto the sensor), and in the resulting output (which for DoF calculations is assumed to be an 8x10" print).
 

stevelee

FT-QL
Jul 6, 2017
1,259
288
Davidson, NC
From age c. 19-22 I used my first 35mm camera, a Yashica rangefinder with a 45mm lens. Since it was the only camera I used, I didn’t have to have the camera with me to compose and previsualize the picture. I did have to get the camera to take the picture. When I looked through the viewfinder, I could see the finished picture better than I can now with an OVF or LCD. It probably helped that it was very close to a theoretical “normal” lens, so my brain didn’t have to resize it. Focusing was never an issue, thanks to the rangefinder.

I was glad to get the SLR, and I still enjoy the aesthetic experience of looking through an OVF. Some things were lost and some were gained in the process.