I checked the file at ISO 6400, the highest ISO I am willing to shoot at on a high-resolution body. I like what I'm seeing.
The ISO on the Phase One should be 2600 to be equivalent to full-frame ISO 6400 (the crop factor is 0.64).
The nearest ISO in the DP Review is 3200.
You may want to re-do your comparison (to be fair to Phase One).
ISO equivalence only applies for specific "equivalent image" assumptions (framing, dof, export size, etc.). It does not mean ISO 2600 on the PO is _literally_ the same as ISO 6400 on full frame.
The comparison is between actual files. ISO 6400 vs ISO 6400 is already a fair comparison.
deepDEEPpurple wrote:
ISO equivalence only applies for specific "equivalent image" assumptions (framing, dof, export size, etc.). It does not mean ISO 2600 on the PO is _literally_ the same as ISO 6400 on full frame.
The comparison is between actual files. ISO 6400 vs ISO 6400 is already a fair comparison.
"Fair" in photography is when the same amount of light (roughly the same number of photons) is allowed to reach the sensors under a comparison.
When ISO is 6400 on both FF and MF, the latter is allowed to receive ca. 2.5 times more light. I actually made a mistake in my previous post: to be equivalent, the FF ISO should be near 2600 on a FF camera when the Phase One ISO is at 6400.
Question here that I have not seen the answer to. While I understand that there is still some rolling shutter on the new A7R VI when looking at golf swings or baseball swings and the shape of the ball when compared to the A1 or A1 II what kind of distortion do you see with the wings of birds in flight or other wildlife? I’m considering buying the new body and really have no plans to use it at baseball or golf matches but only for wildlife shooting. Will you see a lot of distortion only with birds or really not at all since the flapping of bird wings is not as fast. At least not for hummingbirds.
Really would like to know what to expect. Thank you if anyone knows.
ruthenium wrote:
"Fair" in photography is when the same amount of light (roughly the same number of photons) is allowed to reach the sensors under a comparison.
When ISO is 6400 on both FF and MF, the latter is allowed to receive ca. 2.5 times more light. I actually made a mistake in my previous post: to be equivalent, the FF ISO should be near 2600 on a FF camera when the Phase One ISO is at 6400.
Yes, when a FF and a MF camera are set to the same ISO, aperture, and shutter speed, they will both expose to the same EV. Since aperture and shutter speed are the same, the "amount of light per sensor area" (in lux*sec or lumen*sec per sq meter) is the same, and the bigger MF sensor receives more total light.
By comparing FF ISO 2600 to MF ISO 6400 you would compensate for this area difference by changing how much signal amplification the FF sensor gives to each pixel, but to get the same EV as before, this requires lengthening the shutter time or opening up the aperture. Parameters are coupled and some choices have to be made, so I personally prefer setting the ISO the same so that all cameras get the same EV if they're set to the same aperture and shutter speed.
You've already made it clear by your one-liners that you are the most prepared guy in this forum.
I can't wait to read what you come up with when you go over this limit. Make sure to delve deep into pixel pitch, differences in sensor technology, exposure, etc.
Rialto wrote:
Yes, when a FF and a MF camera are set to the same ISO, aperture, and shutter speed, they will both expose to the same EV. Since aperture and shutter speed are the same, the "amount of light per sensor area" (in lux*sec or lumen*sec per sq meter) is the same, and the bigger MF sensor receives more total light.
By comparing FF ISO 2600 to MF ISO 6400 you would compensate for this area difference, and reveal the "per sensor area noise" performance of the sensors.
I can suggest a small textual correction: the "amount of light per sensor area" should be "amount of light per UNIT area" ("per sensor area" can be understood as per entire sensor). Indeed, this is what "exposure" means in photographic terminology.
I find your last sentence is unnecessarily complicated; thus, it can be misunderstood.
"this area difference" can be more specific as "the difference in the sensor surface area"
I am not sure what you mean by "per sensor area noise" (maybe removing the "area" can make it better).
Noise in a photo is relative to light. Thus, a correct comparison of noise from two sensors requires the same amount of light. The ISO acts as a light meter and correlates with lux. The amount of light on two sensors of different sizes is the same when ISO(on the larger sensor) = ISO (on the smaller sensor) x the ratio of the surface areas of the two sensors.
If the ISO is the same on both, one can immediately tell that the larger sensor received more light and should display less noise at the same brightness.
In general, there might be some misunderstanding of the advantage of larger sensors, and there might be some mistaken belief that larger sensors give better image quality (less noise) at high ISO (that is in low light). This is incorrect, and comparing a FF and a MF camera at ISO6400 is inappropriate and misleading.
The principal advantage of MF vs FF is at the base ISO and near the base ISO - this is when the MF can collect more light. Another advantage is, possibly, at the ISO when dual gain is activated. For example, on my Sony A1 and Fujifilm GFX100S II the equivalent ISO are ca. 320 and 500, respectively. The corresponding photographic dynamic range (PDR) is 9.55 (A1) vs 10.87 (GFX100S II), mostly because the dual gain is implemented at ISO500 on the GFX. Normally, the PDR (which is derived from the signal-to-noise ratio) can be expected to be practically the same at equivalent ISOs
RoamingScott wrote:
Now do pixel pitch, smart guys
As I mentioned above, normally, the PDR (which is derived from the signal-to-noise ratio) can be expected to be practically the same at equivalent ISOs, for modern sensors of different sizes. You can easily verify this on photonstophotos.
To the best of my understanding, the pixel pitch is irrelevant in practice when there are 10-20 pixels within the circle of confusion. This condition is true for practically every case excluding major cropping and very large printing.
old-gregg wrote:
dpreview just published their RAW samples for the test scene and they're spectacular. The noise is visibly lower than the A7RV at all ISO settings. As expected, the new R is the new king of IQ in the FF format.
Yeah, I updated to Adobe Camera Raw 18.3.1, downloaded the Studio high ISO RAW files from DPReview, applied Adobe's AI Denoise, and I think even the ISO 12.800 looks pretty darn good!
ruthenium wrote:
I can suggest a small textual correction: the "amount of light per sensor area" should be "amount of light per UNIT area" ("per sensor area" can be understood as per entire sensor). Indeed, this is what "exposure" means in photographic terminology.
I find your last sentence is unnecessarily complicated; thus, it can be misunderstood.
"this area difference" can be more specific as "the difference in the sensor surface area"
I am not sure what you mean by "per sensor area noise" (maybe removing the "area" can make it better).
Noise in a photo is relative to light. Thus, a correct comparison of noise from two sensors requires the same amount of light. The ISO acts as a light meter and correlates with lux. The amount of light on two sensors of different sizes is the same when ISO(on the larger sensor) = ISO (on the smaller sensor) x the ratio of the surface areas of the two sensors.
If the ISO is the same on both, one can immediately tell that the larger sensor received more light and should display less noise at the same brightness.
In general, there might be some misunderstanding of the advantage of larger sensors, and there might be some mistaken belief that larger sensors give better image quality (less noise) at high ISO (that is in low light). This is incorrect, and comparing a FF and a MF camera at ISO6400 is inappropriate and misleading.
The principal advantage of MF vs FF is at the base ISO and near the base ISO - this is when the MF can collect more light. Another advantage is, possibly, at the ISO when dual gain is activated. For example, on my Sony A1 and Fujifilm GFX100S II the equivalent ISO are ca. 320 and 500, respectively. The corresponding photographic dynamic range (PDR) is 9.55 (A1) vs 10.87 (GFX100S II), mostly because the dual gain is implemented at ISO500 on the GFX. Normally, the PDR (which is derived from the signal-to-noise ratio) can be expected to be practically the same at equivalent ISOs...Show more →
Thanks for your detailed response!
Yes, I realize the "per sensor area noise" phrase is something I cannot quantify very well, so I edited that out.
ruthenium wrote:
"Fair" in photography is when the same amount of light (roughly the same number of photons) is allowed to reach the sensors under a comparison.
When ISO is 6400 on both FF and MF, the latter is allowed to receive ca. 2.5 times more light. I actually made a mistake in my previous post: to be equivalent, the FF ISO should be near 2600 on a FF camera when the Phase One ISO is at 6400.
I am so happy I stopped caring about noise and image compassions about 20 years ago. Did you folks already figure out the difference between dpi and image dimensions?
olegkin wrote:
I am so happy I stopped caring about noise and image compassions about 20 years ago. Did you folks already figure out the difference between dpi and image dimensions?
I understand how it can be nice not to care about minute details. But I rather don't understand how some are proud to not understand stuff to the degree that they have to tell the world about it.
swldstn wrote:
Question here that I have not seen the answer to. While I understand that there is still some rolling shutter on the new A7R VI when looking at golf swings or baseball swings and the shape of the ball when compared to the A1 or A1 II what kind of distortion do you see with the wings of birds in flight or other wildlife? I’m considering buying the new body and really have no plans to use it at baseball or golf matches but only for wildlife shooting. Will you see a lot of distortion only with birds or really not at all since the flapping of bird wings is not as fast. At least not for hummingbirds.
Really would like to know what to expect. Thank you if anyone knows....Show more →
It won't be any good for hummingbirds or other small birds unless you use mechanical shutter. It will be about the same as the R5 was - so fine for most medium/large birds but expect the background to be wonky if you are panning horizontally tracking a bird or other subject.
You will be far better off with an A1/ A9 / Z8 / Z9.
Daran wrote:
I understand how it can be nice not to care about minute details. But I rather don't understand how some are proud to not understand stuff to the degree that they have to tell the world about it.
I came here for insights into a new camera. Instead, I got a tedious lecture about the amount of light hitting the sensor, a topic that became boring and unhelpful long ago. A discussion of which side of the camera the lens release button should sit on would have been more useful. Your understanding of people and their motives is lacking.
olegkin wrote:
I came here for insights into a new camera. Instead, I got a tedious lecture about the amount of light hitting the sensor, a topic that became boring and unhelpful long ago. A discussion of which side of the camera the lens release button should sit on would have been more useful. Your understanding of people and their motives is lacking.
This is a Gear Forum, so we discuss equipment. The a7rVI has a new and unique sensor so that is an exciting topic! For me it is the main reason to buy the camera. Obviously there are other choices in E mount and other brands/formats as well.
Does anyone know if there will be a way to turn off dual gain for photos? If so, I wonder if it would speed up readout time too. 8ms would still be about 2x as slow as the a1, but would be a lot more useful than a 20ms redout for moving subjects. Then, depending on our subject, we can decide if we want better dynamic range or readout times.
olegkin wrote:
I came here for insights into a new camera. Instead, I got a tedious lecture about the amount of light hitting the sensor, a topic that became boring and unhelpful long ago. A discussion of which side of the camera the lens release button should sit on would have been more useful. Your understanding of people and their motives is lacking.
Fair enough, I have one on order for reasons that were important to me, so if you would share what aspects of the camera might make, or break your decision to purchase, we can steer the conversation a bit your way.
Does anyone know if there will be a way to turn off dual gain for photos? If so, I wonder if it would speed up readout time too. 8ms would still be about 2x as slow as the a1, but would be a lot more useful than a 20ms redout for moving subjects. Then, depending on our subject, we can decide if we want better dynamic range or readout times.
If it is the same as the A7V then DGO is only available when shooting Mechanical Shutter. So in ES it should be "off".
I still believe that the shutter read is going to be half of the reported 20ms when you use the camera in Lossy Compressed RAW and ES. The A7RIV/V was twice as fast in Lossy Compressed.
So 10ms. If that turns out to be true then rolling shutter won't be much of a concern for birds. Not sure about sports?
https://i.imgur.com/6Gw6Z50.png
