80D is here

coolshot wrote in post #17902840
Is 4k really important? I am a tech enthusiast, but I don't have a single 4k panel in the home. I have 3 LCD tvs in the house and 14 displays(including family tablets,laptops & phones). Short of someone buying midrange 4k tvs from Costco, how they watching 4k content?

FEChariot wrote in post #17902850
At the distance I sit from our main TV and its size that I am limited to because it's in a custom cabinet, I have a hard time telling 720p and 1080P apart. I did some number crunching based on assumptions about 4K I got from reading an article I came across at the time and I would need a 120" tv assuming 20/20 vision to be able to tell the difference.

So I think it's kind of pointless but if I were a company trying to make a sale over my competitors, I would at least offer a product with specs at least as good as the competition or offer it comparitively cheaper.

Human eye is said to resolve 0.5 seconds of arc...It can detect a single dot ...

• at 10' distance on a 1080p screen which is 33" across
  
• at 20' distance on a 1080p screen which is 66" across
  
• at 30' distance on a 1080p screen which is 100" across
  
• at 40' distance on a 1080p screen which is 133" across
  

• at 10' distance on a 4K screen which is 71" across
  
• at 20' distance on a 4K screen which is 142" across
  
• at 30' distance on a 4K screen which is 214" across
  
• at 40' distance on a 4K screen which is 285" across
  
• at 80' distance on a 4K screen which is 570" across
  

Immaculens wrote in post #17943424
I believe centre focus point is good for many lenses. Only a few select Canon lenses will AF using the various focus points

Of course, if the camera doesn't know that the TC is there, all AF points work, even if they are slower. In such a case, I would expect an AF point that can potentially work at f/8 to work better than one that is not supposed to work at f/8 at all. IOW, the 80D will probably work better "tricked" into f/8 AF than f/5.6-only cameras.

I only raise the issue because with both the 7D2 and ID IV, you only get center point or expanded center point when using a 1.4X teleconverter on a f/5.6 lens like the 100-400 ii. I don't know what impact having 27 points would make in real world circumstances, but 27 vs. 5 (at the most) seems significant.

Wilt wrote in post #17943444
Human eye is said to resolve 0.5 seconds of arc...It can detect a single dot ...

• at 10' distance on a 1080p screen which is 33" across
  
• at 20' distance on a 1080p screen which is 66" across
  
• at 30' distance on a 1080p screen which is 100" across
  
• at 40' distance on a 1080p screen which is 133" across
  

At those listed distances, if your screen is any smaller than the listed horizontal size, you CANNOT detect a single pixel!

4096 pixels which are same size as above means the eye can detect a pixel

• at 10' distance on a 4K screen which is 71" across
  
• at 20' distance on a 4K screen which is 142" across
  
• at 30' distance on a 4K screen which is 214" across
  
• at 40' distance on a 4K screen which is 285" across
  
• at 80' distance on a 4K screen which is 570" across
  

So at a viewing distance of 10' improving the screen resolution to better than 1080p when it is > 33" across indeed would be of benefit.
And if you do not want to see a 0.14" single pixel at the cinema with 43' wide 4K digital projection, do not sit closer than 72'.

I never believe any of these anecdotes and "facts" about the limits of human perception. They almost always come from someone who wants to prove a point and/or has a pathological need to draw lines in the sand.

Placement of edges and resolution of modulations are two completely different components of vision, IMO.

Do you believe that if you put a B&W single-pixel checker pattern on a monitor and walked away from it until it looked solid gray to you, that you are at the limit of what you can appreciate? That no smoother curves or more accurate placement of edges could be appreciated with a finer monitor at the same distance? I think not.

John Sheehy wrote in post #17943274
Well, it's lower at base ISO, so it has to cross somewhere.

Looks like it's around ISO 800, from the graph posted earlier in the thread (if DR maps into that particular type of noise - which I accept may not be the case).

John Sheehy wrote in post #17943274
Usable for what? I've never subscribed to the idea of ISO limits. Quality depends on lots of factors, like whether you need fine details, especially color ones; how much you need to crop and/or magnify, what color the lighting is, etc.

Usable for my personal acceptable level of quality for what I print or display (which is of course what most people actually mean when they make definitive statements about something being "good" or "bad" )

On the 7DI and 60D I generally didn't like ISO 3200. The 5D3 unsurprisingly is fine (for me) at ISO 3200, and, perhaps because of slightly better noise character, I feel that ISO 6400 on the 5D3 is better than 3200 on the 7D/60D. As such, I'd be surprised if ISO 12800 or 25600 would be of interest to me on the 80D - but if ISO 3200 is usable I'll be pretty happy. Again - all based on my subjective preferences.

AJSJones wrote in post #17943306
Now that would be convenient - Auto-ISO-ETTR. Not difficult to program if they can already provide zebra stripes at different levels approaching pixel saturation. You just set how close you want to go to full-well and have 95% of that start blinking in case the "auto" needs an assist (or a LUT says it's better to keep the ISO lower and raise it in post, based on known ISO noise characteristics for the sensor at hand).

As long as the selection of "optimum" is based on overall noise rather than max (amplified) signal - once the shutter and aperture have been set, the number of photons is fixed and the rest is electronics...

Exactly. In fact, I believe Magic Lantern has a form of auto ETTR already.

Point being, the camera manufacturer knows the optimum camera settings - e.g. whether it is better to increase the ISO for analog gain benefits, or whether there's no point (thus to cap the ISO and record a digital ISO "offset" in the RAW metadata).

Phoenixkh wrote in post #17943477
I only raise the issue because with both the 7D2 and ID IV, you only get center point or expanded center point when using a 1.4X teleconverter on a f/5.6 lens like the 100-400 ii. I don't know what impact having 27 points would make in real world circumstances, but 27 vs. 5 (at the most) seems significant.

Without trying to sound trite; it would be the difference between shooting centre point only, and having 27 points... surely? I.e. probably quite useful.

Another issue with 4K is that it eats up memory cards like crazy, and in some cameras eats battery power faster than HD. I might be more enthused in a year or so when I have something to actually watch it on.

sploo wrote in post #17943214
Isn't it a case though that the ideal exposure system would allow you to choose an aperture (for desired depth of field), a shutter speed (for desired blurring or freezing of motion, as appropriate), and the camera to then capture the scene with your brightest desired highlight just under clipping (that area/region/brightness could be chosen like choosing an AF point).

How those tones are then reproduced is the job of post. The job of the camera is to capture the scene with the best possible quality; if that's ISO 43, 100, 200, so be it.

Ah, so you do choose your own brightest highlight. Sure.

In fact, the old film Canon T90 could do precisely that.

Immaculens wrote in post #17943407
Just noticed the top dial has a C1 and C2... helpful little upgrade...

That' s pretty much the only thing that I'd personally get true benefit from compared to the 70D.

sploo wrote in post #17943501
Without trying to sound trite; it would be the difference between shooting centre point only, and having 27 points... surely? I.e. probably quite useful.

At first glance, it does seem obvious.... but I don't use all 45 auto focus points when they are available to me on my 1D IV. I tend to use expanded center point or just the center point by itself. This is my go to setting when taking wildlife photographs but I am starting to experiment a bit more.

That's why I'm thinking out loud in font on a camera forum site.

Windsun33 wrote in post #17943514
Another issue with 4K is that it eats up memory cards like crazy, and in some cameras eats battery power faster than HD. I might be more enthused in a year or so when I have something to actually watch it on.

4K with smaller sensors is kinda overrated, imho. I'd take my Super 35 sensors with high quallity 1080p over any barely-there-4K (3840) micro 4/3rd or 1 inch sensor cameras (cough, Panosonic, cough, Sony Point and Shoot series). Most people never touch video on their DSLR's, or barely dabble in amateur video with their A7's anyways.

I am pleased with the size of a crop sensor for photo quality and, 'certainly' video quality. Wow do I not care if my features support 4K video or not. 720 or even 1080 on a typical tv is just dandy. Serious about video recording? Upgrade appropriately and keep dslr's out of it. It is a dslr... 'photopraphy'. That is records high quality video is a plus...

bumpintheroad wrote in post #17943420
I think the f/8 is only for specific lenses with teleconverters.

Most EF lenses with TC will AF @ f/8 - center point only.

f/8 AF @ 27 points only with EF 100–400mm f/4.5–5.6L IS II + Extender EF 1.4x III and
EF 200–400mm f/4L IS Extender 1.4x lens + Extender EF 2x III (built-in extender not used)
http://learn.usa.canon​.com …16/eos-80D/af_at_f8.shtml

That sounds like good news for us 100-400 II owners. Perhaps those who can afford the 200-400 f/4 would prefer a different body anyway.

RDKirk wrote in post #17943551
Ah, so you do choose your own brightest highlight. Sure.

Absolutely. Without that, as you noted, the camera can't know the photographer's intention (i.e. what compromise the shooter is willing to make in clipping highlights vs getting more shadow detail). For me, the metering system just needs to let you chose your aperture and shutter speed (for DOF and movement) and then chose what highlight you want to keep. From there, the camera should be able to choose the most appropriate ISO setting given internal knowledge of what would give the best signal to noise ratio.

Phoenixkh wrote in post #17943566
At first glance, it does seem obvious.... but I don't use all 45 auto focus points when they are available to me on my 1D IV. I tend to use expanded center point or just the center point by itself. This is my go to setting when taking wildlife photographs but I am starting to experiment a bit more.

That's why I'm thinking out loud in font on a camera forum site.

Ah. Well, if you tend to only use the centre point then having more is obviously moot

Although I'm not a wildlife guy (long lenses + TC => f/8) I can see the usefulness of being able to track with off centre points, as it gives some more scope for framing.

idkdc wrote in post #17943569
4K with smaller sensors is kinda overrated, imho. I'd take my Super 35 sensors with high quallity 1080p over any barely-there-4K (3840) micro 4/3rd or 1 inch sensor cameras (cough, Panosonic, cough, Sony Point and Shoot series). Most people never touch video on their DSLR's, or barely dabble in amateur video with their A7's anyways.

Interesting point about smaller sensors. But, if you have sufficient light, then surely there's no disadvantage to having a smaller sensor (other than reduced capability for shallow DOF I guess). As a very unscientific point - I do notice that the photographic image quality on a modern smartphone is usually quite impressive in good light, but really grotty (compared to a DSLR) in anything else.

I do also wonder if a lot of the problems with 4K video on smaller devices is down to the quality of the compression algorithms. Broadcast bit rates for 4K seem to be around 40Mb/s (5MB/s), so well within the capability of even an SD card - but, you've obviously got to compress those 4K frames in real time. I suspect a lot of corners need to be cut in order to do that on a smaller device. Probably also the reason why the 1Dx II is using MJPEG (essentially, just a flick book of photos) - but then the bandwidth requirement is massive.

John Sheehy wrote in post #17943484
I never believe any of these anecdotes and "facts" about the limits of human perception. They almost always come from someone who wants to prove a point and/or has a pathological need to draw lines in the sand.

Placement of edges and resolution of modulations are two completely different components of vision, IMO.

Do you believe that if you put a B&W single-pixel checker pattern on a monitor and walked away from it until it looked solid gray to you, that you are at the limit of what you can appreciate? That no smoother curves or more accurate placement of edges could be appreciated with a finer monitor at the same distance? I think not.

So you do not believe your optometrist? Those values of human visual acuity are founded upon the principle.