December 15, 2017, 01:15:31 PM

Author Topic: Sony A7R3 manual drops -- here comes the fine print  (Read 4681 times)

ahsanford

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Re: Sony A7R3 manual drops -- here comes the fine print
« Reply #30 on: November 08, 2017, 04:05:18 PM »
Re: temperature of the camera (not the WB):

"If the same part of your skin touches the camera for a long period of time while using the camera, even if the camera does not feel hot to you, it may cause symptoms of a low-temperature burn such as redness or blistering."  (Page 8.)

- A

Yeh, ever look at page 20 of the 1DX MkII manual?

Or page 15 of the 5D MkIII manual?

FAKE NEWS!

Honestly never knew this about my 5D3, thanks.

- A

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Re: Sony A7R3 manual drops -- here comes the fine print
« Reply #30 on: November 08, 2017, 04:05:18 PM »

Tugela

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Re: Sony A7R3 manual drops -- here comes the fine print
« Reply #31 on: November 15, 2017, 03:41:25 PM »
I’m not sure I’d call the AF lock thing “shenanigans.” The fact that it will (allegedly) focus at f/11 at all is noteworthy. My 1dx won’t even try.

What aperture the lens uses to AF vs. capture the shot are different things, aren't they?   My 5D3 can take continuous shots at f/11, f/14, etc. with working AF provided the lens is capable of f/5.6 or quicker, correct?

For instance, I'm looking through the front element as I half-shutter for AF on my 5D3 and my 35 f/2 lens set at f/11 is autofocusing (to my eye) wide open.  The f/11 closing of the blades doesn't happen until I actually take the shot.

Oh... is this a mirrorless/liveview vs. SLR AF thing I'm missing?   I just repeated the exercise on my 5D3 -- but this time in LiveView -- and the half shutter press for AF did indeed close the iris down.

- A

When the camera is doing burst shooting the aperture likely stays stopped down, so focusing is difficult as a result. The only time the camera will be able to focus like that would be immediately prior to the sequence starting. The focusing then would be done with the aperture wide open and consequently gets the benefit of narrow dof.

That is not a surprising thing when you think about what is actually happening with the camera while the burst is in progress.

Tugela

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Re: Sony A7R3 manual drops -- here comes the fine print
« Reply #32 on: November 15, 2017, 03:50:00 PM »
I’m not sure I’d call the AF lock thing “shenanigans.” The fact that it will (allegedly) focus at f/11 at all is noteworthy. My 1dx won’t even try.

You're confusing the max aperture of the lens with the set value.  Your 1D X won't AF through the viewfinder with an f/11 max lens (e.g., a 400/5.6 + 2x TC), although it will AF in live view with that combo.  But if you set your 70-200mm f/4 lens to f/11, your camera will happily focus between shots in AI Servo.  The Sony focuses at the aperture you choose for the shot, so if you mount an f/4 lens and set the aperture to f/11, the camera won't focus between shots even if set to AF-C. 

That certainly fits my definition of shenanigans.

No. You are comparing a situation where the apeture resets with every shot to one where it is continually stopped down. A lens can focus easily when it is wide open because dof is narrow and the computer can lock it down quickly. But when the lens is stopped down dof is broad and consequently it will take the computer much longer to find focus. When you are shooting at very high speed bursts that length of time required to focus will exceed that available before the next frame is shot, and that is why focus is fixed with the first frame. With wider apetures there is enough time to focus before the next shot, so every shot will focus properly.

It is not shenanigans, it is you not understanding how cameras and their integrated computers work.

neuroanatomist

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Re: Sony A7R3 manual drops -- here comes the fine print
« Reply #33 on: November 15, 2017, 04:13:04 PM »
No. You are comparing a situation where the apeture resets with every shot to one where it is continually stopped down. A lens can focus easily when it is wide open because dof is narrow and the computer can lock it down quickly. But when the lens is stopped down dof is broad and consequently it will take the computer much longer to find focus. When you are shooting at very high speed bursts that length of time required to focus will exceed that available before the next frame is shot, and that is why focus is fixed with the first frame. With wider apetures there is enough time to focus before the next shot, so every shot will focus properly.

It is not shenanigans, it is you not understanding how cameras and their integrated computers work.

So why not simply open the aperture between between frames, focus, then stop the aperture back down for image capture?  Do you understand that's exactly what Canon dSLRs do, and my 1D X can shoot 12 fps and still AF between each frame of the burst?  So, is it simply that Canon's cameras and their integrated computers just work better than Sony's, or is it just Sony shenanigans?  You pick.

By the way, how did that, "All Canon cameras with Digic 7 will shoot 4K," claim of yours work out?   ::)
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AlanF

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Re: Sony A7R3 manual drops -- here comes the fine print
« Reply #34 on: November 15, 2017, 05:47:34 PM »
Concerning the camera temperature - that's crazy :) I think that's probably the reason why they are rushing this poor camera to the market. They want to sell as much as they can while it's cold and people didn't realize it'll overheat during the summer.

Up here in Canada, a camera that helps keep you hands warm could be a great marketing feature!

Canon cameras don’t have a built in hand warmer..... Canon is doomed!

As a Canadian you must surely know by heart:

https://www.poetryfoundation.org/poems/45081/the-cremation-of-sam-mcgee

 And there sat Sam, looking cool and calm, in the heart of the furnace roar;
And he wore a smile you could see a mile, and he said: "Please close that door.
It's fine in here, but I greatly fear you'll let in the cold and storm—
Since I left Plumtree, down in Tennessee, it's the first time I've been warm."
5D IV, 5DS R, 400mm DO II, 1.4xTC III, 2xTC III, EF 1.8 STM,  EF 24-105, 100-400 II, EF-S 15-85, Sigma 150-600mm C, EOS-M5 15-45, f/2 22, 11-22, Samyang 8mm f/2.8 fisheye: sold 7D II, EOS-M, Powershot G3 X,  Sigma 10-20, EF 300/2.8 II, 70-200/4 IS.

Tugela

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Re: Sony A7R3 manual drops -- here comes the fine print
« Reply #35 on: November 20, 2017, 06:37:05 AM »
No. You are comparing a situation where the apeture resets with every shot to one where it is continually stopped down. A lens can focus easily when it is wide open because dof is narrow and the computer can lock it down quickly. But when the lens is stopped down dof is broad and consequently it will take the computer much longer to find focus. When you are shooting at very high speed bursts that length of time required to focus will exceed that available before the next frame is shot, and that is why focus is fixed with the first frame. With wider apetures there is enough time to focus before the next shot, so every shot will focus properly.

It is not shenanigans, it is you not understanding how cameras and their integrated computers work.

So why not simply open the aperture between between frames, focus, then stop the aperture back down for image capture?  Do you understand that's exactly what Canon dSLRs do, and my 1D X can shoot 12 fps and still AF between each frame of the burst?  So, is it simply that Canon's cameras and their integrated computers just work better than Sony's, or is it just Sony shenanigans?  You pick.

By the way, how did that, "All Canon cameras with Digic 7 will shoot 4K," claim of yours work out?   ::)

There is a physical limit on how quickly mechanical devices such as iris blades can work, so at very high frame rates they will have to be kept stopped down. Most modern Canon DSLRs can image at 60 fps or more, but there is absolutely no way their iris blades can flex at that rate. DSLR focusing works in a different way, and has far fewer focusing elements, so the overhead on the processor is lower. Accurate focusing requires shallow depths of field, and at 20 fps with a full sensor read (which the Canon processors can't handle) when you need to keep the aperture stopped down you are not going to have enough time to calculate the focus point at small apertures. That is the price you pay for very high frame rates. Canon would have the same problem if they shot at those frame rates. At that speed focusing would have to be handled like video focusing, which does not happen every frame but rather happens dynamically over a number of frames and is independent of the frame rate itself. You need the aperture stopped down for that since you are monitoring trends over time and using that to control focusing. Which is fine for video but obviously would less optimal for stills where you would want focus on every frame. That is where the compromise comes in, it is to enable those high frame rates where the data that is used for focus calculation is less optimal. In situations where you have enough data (wider apertures/lower dof) you can focus at those frame rates. The Sony is behaving more like a video camera at those high frame rates, something the Canon can't do unless it also behaves like a video camera (in which case it will experience the exact same problem).

In any case it is academic since I doubt there is any lens that can focus fast enough at that frame rate. No matter what camera you have it is going to be an approximation.

The hardware for 4K is there in the latest Digic, it just isn't implemented due to the processor overheating. The Digic 7 and the DV5 are the same processors for the most part, just like all of the earlier processors came in families. They don't redesign the processor separately for video or stills, the core logic is the same, you just have areas enabled/disabled to optimize performance for a particular application. Likewise the DV6 will be the same as the Digic 8, when it is eventually used. The DV6 implementations appear to have fans as well, so we may still not get hardware 4K in Digic 8, if the thermal envelope is not yet controlled enough.

neuroanatomist

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Re: Sony A7R3 manual drops -- here comes the fine print
« Reply #36 on: November 20, 2017, 08:03:21 AM »
No. You are comparing a situation where the apeture resets with every shot to one where it is continually stopped down. A lens can focus easily when it is wide open because dof is narrow and the computer can lock it down quickly. But when the lens is stopped down dof is broad and consequently it will take the computer much longer to find focus. When you are shooting at very high speed bursts that length of time required to focus will exceed that available before the next frame is shot, and that is why focus is fixed with the first frame. With wider apetures there is enough time to focus before the next shot, so every shot will focus properly.

It is not shenanigans, it is you not understanding how cameras and their integrated computers work.

So why not simply open the aperture between between frames, focus, then stop the aperture back down for image capture?  Do you understand that's exactly what Canon dSLRs do, and my 1D X can shoot 12 fps and still AF between each frame of the burst?  So, is it simply that Canon's cameras and their integrated computers just work better than Sony's, or is it just Sony shenanigans?  You pick.

By the way, how did that, "All Canon cameras with Digic 7 will shoot 4K," claim of yours work out?   ::)

There is a physical limit on how quickly mechanical devices such as iris blades can work, so at very high frame rates they will have to be kept stopped down. Most modern Canon DSLRs can image at 60 fps or more, but there is absolutely no way their iris blades can flex at that rate. DSLR focusing works in a different way, and has far fewer focusing elements, so the overhead on the processor is lower. Accurate focusing requires shallow depths of field, and at 20 fps with a full sensor read (which the Canon processors can't handle) when you need to keep the aperture stopped down you are not going to have enough time to calculate the focus point at small apertures. That is the price you pay for very high frame rates. Canon would have the same problem if they shot at those frame rates. At that speed focusing would have to be handled like video focusing, which does not happen every frame but rather happens dynamically over a number of frames and is independent of the frame rate itself. You need the aperture stopped down for that since you are monitoring trends over time and using that to control focusing. Which is fine for video but obviously would less optimal for stills where you would want focus on every frame. That is where the compromise comes in, it is to enable those high frame rates where the data that is used for focus calculation is less optimal. In situations where you have enough data (wider apertures/lower dof) you can focus at those frame rates. The Sony is behaving more like a video camera at those high frame rates, something the Canon can't do unless it also behaves like a video camera (in which case it will experience the exact same problem).

In any case it is academic since I doubt there is any lens that can focus fast enough at that frame rate. No matter what camera you have it is going to be an approximation.

The hardware for 4K is there in the latest Digic, it just isn't implemented due to the processor overheating. The Digic 7 and the DV5 are the same processors for the most part, just like all of the earlier processors came in families. They don't redesign the processor separately for video or stills, the core logic is the same, you just have areas enabled/disabled to optimize performance for a particular application. Likewise the DV6 will be the same as the Digic 8, when it is eventually used. The DV6 implementations appear to have fans as well, so we may still not get hardware 4K in Digic 8, if the thermal envelope is not yet controlled enough.

Let me explain. No, there is too much…let me sum up:

Canon ILCs can focus in between frames while tracking a subject in a high fps burst (even my EOS M6 will AF between frames while tracking at 7 fps), Sony ILCs lock focus after the first frame of the burst which means moving subjects will often move OOF; and when you stated, "All Canon cameras with Digic 7 will shoot 4K," you were wrong. 
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Re: Sony A7R3 manual drops -- here comes the fine print
« Reply #36 on: November 20, 2017, 08:03:21 AM »

bhf3737

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Re: Sony A7R3 manual drops -- here comes the fine print
« Reply #37 on: November 20, 2017, 12:18:07 PM »
There is a physical limit on how quickly mechanical devices such as iris blades can work, so at very high frame rates they will have to be kept stopped down. Most modern Canon DSLRs can image at 60 fps or more, but there is absolutely no way their iris blades can flex at that rate. DSLR focusing works in a different way, and has far fewer focusing elements, so the overhead on the processor is lower. Accurate focusing requires shallow depths of field, and at 20 fps with a full sensor read (which the Canon processors can't handle) when you need to keep the aperture stopped down you are not going to have enough time to calculate the focus point at small apertures. That is the price you pay for very high frame rates. Canon would have the same problem if they shot at those frame rates. At that speed focusing would have to be handled like video focusing, which does not happen every frame but rather happens dynamically over a number of frames and is independent of the frame rate itself. You need the aperture stopped down for that since you are monitoring trends over time and using that to control focusing. Which is fine for video but obviously would less optimal for stills where you would want focus on every frame. That is where the compromise comes in, it is to enable those high frame rates where the data that is used for focus calculation is less optimal. In situations where you have enough data (wider apertures/lower dof) you can focus at those frame rates. The Sony is behaving more like a video camera at those high frame rates, something the Canon can't do unless it also behaves like a video camera (in which case it will experience the exact same problem).

In any case it is academic since I doubt there is any lens that can focus fast enough at that frame rate. No matter what camera you have it is going to be an approximation.

The hardware for 4K is there in the latest Digic, it just isn't implemented due to the processor overheating. The Digic 7 and the DV5 are the same processors for the most part, just like all of the earlier processors came in families. They don't redesign the processor separately for video or stills, the core logic is the same, you just have areas enabled/disabled to optimize performance for a particular application. Likewise the DV6 will be the same as the Digic 8, when it is eventually used. The DV6 implementations appear to have fans as well, so we may still not get hardware 4K in Digic 8, if the thermal envelope is not yet controlled enough.

It seems that there is confusion in your statement about how still and video cameras process images they take.
There are 3 sets of core functionalities in both still and video cameras:
1. A/D performed usually by external circuitry to get the image/video signal in.
2. Core ARM based functions that don't change regularly. These include Connectivity (USB, HDMI, SD/CF Cards), sensor (Wifi, GPS, tilt/level), display (LCD back and top, OVF/EVF), actuators (shutter, focus, lens drives, buttons, etc.)
3. Image/Video processing using CPU and GPU, that includes: audio processing (in and out), image/video processing (compression), and DRAM/buffer management.

Depending on how the sensor array processing is performed (4:2:0, 4:2:2, etc. also number of bits for color 8, 10, etc.) and how much of this is pushed off the CPU/GPU to the sensor chip itself the image/video processing may vary. The image/video processing is done within the CPU/GPU using the stored processing software. The processing itself depends on how much data you want to move, how much processing you need (e.g. noise, color profile, edge smoothing, aberration correction, etc.) and how much compression you want to apply to the data before packaging it and sending to the SD/CF cards.
Therefore, there is no fundamental difference between the way the image and video is processed and everything is done with a combination of software and hardware.
Canon's technology encompasses all three areas. The focus in between frames is a technology that Canon has developed and is included in all newer version of its DIGIC processors.
Heat management is part of the design process. There is no dedicated ventilation mechanism for the CPU. If the whole circuitry produces so much heat, fan is added, e.g. in XF series.   
Some other companies concentrate mostly on the third set of functionalities and for some heat management is an after thought.



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Re: Sony A7R3 manual drops -- here comes the fine print
« Reply #37 on: November 20, 2017, 12:18:07 PM »