September 30, 2014, 08:19:34 PM

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Messages - jrista

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46
EOS Bodies / Re: Canon Says Higher Resolution Sensors Are Coming Soon
« on: September 27, 2014, 03:10:24 AM »
I don't want or need the 7d2 - 10 fps is way too fast..and I prefer the FOV of FF.

You can always jack the frame rate down. You have the high speed and low speed continuous modes, so when you don't want to rip out 20 frames a burst, you can always drop down to three or four per second (and I think it's configurable on the high end models...I don't think the 7D allowed it, but the 7D II definitely should).

i am sure it does, and i am sure it has a silent burst too which is throttled down...the bigger aspect is i don't need a crop body, FF has it's claws in me.  I favor splitting the lines more for MP count (too much is not always needed) and low IS quality...  and yeah, i'd rahter other things like higher sync speed than burst.

Yeah, I can understand that. I have uses for crop, but there are ultimately ways of mitigating the need. I can always get closer to my subjects, for example...and if I can get close enough, FF will always win. One advantage that the 7D II can offer that I don't think the 5D III or 1D X could ever really compete with is the ability to get long equivalent focal length at a faster max aperture...allowing the use of more than just the central cluster of AF points at the much slower f/8. The 7D II could achieve an effective 1344mm focal length (FoV equivalent) at f/5.6. At best, FF cameras can achieve 1200mm f/8. The added AF power the 7D II can offer at a very long effective focal length is intriguing.

honestly.... 1344mm focal length... i so have no NEED for that...want...sure...i do like shooting the moon at times...but i really have no bird shooting desire...and...while i do like putting the couple far away from me at times and shooting with the 70-200...for what makes me $$$...no need at all...

on a side note...i just sold a $1000 piece that was shot on...my old 7d...don't even own that now, nor do i still own the lens i it was shot with (the old 244-70mm 2.8)....go 7d...still earning after being sold...lol

Congrats on the sale! Must feel nice.

I don't generally need that kind of focal length myself. I use 1200mm on the 5D III, but usually it's to get headshot closeups of shore and wading birds and waterfowl. I'm usually at 840mm on the 5D III and 600mm on my 7D for birds. I'm usually at 600mm on the 5D III for wildlife (much better FoV than the 7D ever offered). I've used 840mm, and even as much as 1680mm (2x + 1.4x) on the 7D for astro stuff, but at that level diffraction is really kicking in, and I'm better off with a proper large aperture telescope.

47
EOS Bodies / Re: Just for Jrista: 2014 Market Data
« on: September 27, 2014, 03:06:50 AM »
Oh, I agree about the blooming. That's pretty nasty. There are other problems with the A7r as well, if you pull down the RAWs. It has some pretty wicked aliasing and moire in the EVF. When I pointed at the blinds, it was pretty bad.

The focus is also NOT fast. There is only one out of several AF modes available for use with EF lenses, AF-S, which seems to be contrast detect. In better light, there seems to be a quick initial shift, then a slow contrast drive. It's difficult to see what's in focus in the EVF...but, I haven't messed with all the EVF features. Focusing is not intuitive, though.
...

Once you used it a while you won't even notice the aliasing and moire in the viewfinder :). Also I don't know if you already have done this but it is hard to see things in the deep shadows through the VF unless you enable DRO.

Yeah, I enabled DRO. Still messing with all the settings. I do find the EVF to be pretty useless once you get down to around 1/30th second frame rate. I'm not sure why, but the EVF doesn't seem to use simulated exposures like the LCD screen on the back. The LCD screen maintains a high frame rate, but when I use the EVF, it only refreshes at the rate of your shutter speed...so a 1/4s shutter results in truly hideous EVF performance.

I won't get involved in these pointless discussions but I find the discussion about optimal exposure quite symptomatic. With exmor sensors you don't even have to bother thinking about getting the optimal exposure, you can focus on the other stuff and just shoot.

Yeah, I totally agree. I always have to get just the right amount of ETTR with the 5D III, so I'll usually (with landscapes, I work it a bit different with birds and wildlife) take a couple test shots to make sure I have the exposure right. With the A7r, it just isn't an issue...get the exposure generally right, take the shot. If your off by a third of a stop, either over or under exposed, it doesn't matter. You can usually recover it either way. (The A7r seems to have very pessimistic highlight warnings, too...when it shows blinkies, there still seems to be a ton of headroom...and you can even see it in the in-camera histogram.)

48
Technical Support / Re: Dynamic Range questions..
« on: September 27, 2014, 02:46:39 AM »
Hi,
   One think I don't understand is that how a camera can have more than 14 stops of DR when the camera only record in 14-bits... when you record in 14-bits, shouldn't mean that you should have a maximum of 14 stops and not more than that?? Or they don't record that data in a linear way??

   Have a nice day.

It's a conversion from decibels. Downsampling averages noise out. It's like binning or having larger pixels. So, if you start with a D810, with FWC of 78133e- and RN of 5.6e-. Your dynamic range is 20 log(78133/5.6), or ~83dB. Divide by six to get stops: 13.82. If you downsample, you average the read noise. Downsample by a factor of two, you average the read noise. It drops by a factor of the square root of the number of pixels averaged. A factor of 2 downsampling means you average 2x2 (4) pixels together, so your 5.6e- RN drops to 2.8e- RN. Your dynamic range is now 20 log(78133/2.8), or 89dB. That's 14.8 stops.

For comparing cameras, this can be useful. You need to figure out a common size to downsample to for the cameras you are comparing, and calculate the read noise for each one at that specific size. DXO uses an 8x12" 300ppi print target as their common size. So long as you downsample to that exact size, then you could theoretically get more than 14 stops of DR. There are a number of factors with that...for one, you can't edit downsampled RAW images. Downsampling doesn't tell you how much DR the camera can capture in a single shot, either. Only the native DR tells you that.

With a 14-bit ADC, the D810 has 13.8 stops of "hardware DR"...what the sensor itself is capable of actually capturing in a single shot. It gives you an idea of the editing latitude your going to have when pushing exposure around in a program like Lightroom. In the case of the D810, if your screen is an 8-bit screen (likely), then you have 13.8-8, or 5.8 stops worth of shadow lifting ability. Most Canon sensors, with ~11.5 stops of DR, have 11.5-8, or 3.5 stops of shadow lifting ability. (These would basically be absolute maximums with perfect circumstances...your probably going to get less than this in most cases.)

So, the CAMERA does not have more than 14 stops of DR. The IMAGE could be downsampled, which would result in more DR in the image. You can also apply regular old noise reduction routines, and accomplish the same thing...lower noise, more DR. If you want to obliterate high frequency noise in your images (noise at or very near pixel scale), you could buy PixInsight, and apply the TGVDenoise routine. That'll skyrocket your DR (assuming you don't have banding :P). When publishing to the web, most people downsample, so you can generally assume that your final images that you upload to a web site somewhere are going to have lower noise/better DR (overall, not just in the shadows) than what comes out of the camera directly.

49
EOS Bodies / Re: Canon Says Higher Resolution Sensors Are Coming Soon
« on: September 27, 2014, 02:22:48 AM »
I don't want or need the 7d2 - 10 fps is way too fast..and I prefer the FOV of FF.

You can always jack the frame rate down. You have the high speed and low speed continuous modes, so when you don't want to rip out 20 frames a burst, you can always drop down to three or four per second (and I think it's configurable on the high end models...I don't think the 7D allowed it, but the 7D II definitely should).

i am sure it does, and i am sure it has a silent burst too which is throttled down...the bigger aspect is i don't need a crop body, FF has it's claws in me.  I favor splitting the lines more for MP count (too much is not always needed) and low IS quality...  and yeah, i'd rahter other things like higher sync speed than burst.

Yeah, I can understand that. I have uses for crop, but there are ultimately ways of mitigating the need. I can always get closer to my subjects, for example...and if I can get close enough, FF will always win. One advantage that the 7D II can offer that I don't think the 5D III or 1D X could ever really compete with is the ability to get long equivalent focal length at a faster max aperture...allowing the use of more than just the central cluster of AF points at the much slower f/8. The 7D II could achieve an effective 1344mm focal length (FoV equivalent) at f/5.6. At best, FF cameras can achieve 1200mm f/8. The added AF power the 7D II can offer at a very long effective focal length is intriguing.

50
EOS Bodies / Re: More Talk of an October Announcement of a DSLR [CR1]
« on: September 27, 2014, 02:18:09 AM »
I believe, at the high end (for cameras like the 5D III/D800/810, 1D X/D4, 6D/D600), that there has already been a bit of a redistribution of sales. In 2012, Nikon sales of ILC cameras grew dramatically, by 50%. They attributed most of the growth to strong Mirrorless sales, and the D800/E.

I don't know if D800 units sold matches 5D III units sold, all I know is that Nikon attributed a decent amount of their 50% ILC growth in 2012 (the year the D800 was released) to that amazing new camera.

Pre-2012, overall Canon market share was around 45% or so, while Nikon market share was under 30%. The gap was at least 15%. Today, the market share distribution is more like 40% vs. 35%...the gap has shrunk to a mere 5% on average...and as little as 3% (at best for Nikon/worst for Canon).

It's difficult to look at such changes occurring over the last two years, and not think that it has something to do, at least partly, with differences in camera technology (particularly at the high end.) It's impossible to make concrete conclusions, companies don't make the necessary data available. It's just difficult to think the market share shift is entirely unrelated to the differences in sensor technology. (It's also illogical to think it's entirely related to it...or even primarily related to it, but no more logical to think it's unrelated.)

51
EOS Bodies / Re: Canon Says Higher Resolution Sensors Are Coming Soon
« on: September 27, 2014, 01:54:13 AM »
they aren't switching ,in fact many are getting their toes wet with the A7r and not liking it ....lol.  But, even jrista loves the DR doesn't but like the A7r enough to buy...

I'd buy the A7r for landscapes, since I really wouldn't need the majority of it's features. I wouldn't buy it as a general purpose camera...too many issues. Plus, I'm NOT a fan of EVFs...and that isn't a thing unique to the A7r. I'm not buying it yet because I want to see what Sony does next (which isn't far away, if they are really releasing new things in January). If they don't change anything, then I found some used A7r's for $1700, which is a lot more reasonable for a landscape-only camera than $3400 for a D810 (and more for some lenses.)

52
EOS Bodies / Re: Canon Says Higher Resolution Sensors Are Coming Soon
« on: September 27, 2014, 01:49:20 AM »
I don't want or need the 7d2 - 10 fps is way too fast..and I prefer the FOV of FF.

You can always jack the frame rate down. You have the high speed and low speed continuous modes, so when you don't want to rip out 20 frames a burst, you can always drop down to three or four per second (and I think it's configurable on the high end models...I don't think the 7D allowed it, but the 7D II definitely should).

53
@zlatko: It's not about any of that. It's simply data. There are lots of debates that go on about DR. There aren't very many RAW files that people can download and play with themselves. That's all this is about. I'm not trying to push anything with this thread. I'm just trying to provide data. People make decisions. It's useful to have data to back up those decisions.

YES, this is an extreme example. It's not intended to be a totally realistic demonstration. All it is supposed to do is give people who may have questions about what it really means to have more DR the ability to see for themselves. To actually download RAW files that they can open up in their preferred editor, work with themselves, and...see what's what. If some people conclude that more DR does nothing for them, fine. I don't care.

I simply care about providing some concrete data. The DR debate is never going to end until the playing field is level. So it's going to rage on. At least I can provide something people can reference. That's all this is. I am hoping I'll have the opportunity of photographing some landscape scenes tomorrow to provide some more realistic and balanced examples than this. Personally, I'm impressed with how well the A7r holds up under a 5-stop push (especially given it's compression). I don't think that's a particularly common scenario...but the data held up very well, all things considered. For smaller prints, like an 8x10, it's entirely viable.

It won't be any surprise to me if most of the responses to this thread are like yours, this is a Canon community, so it makes sense that people will decry the value of having more DR, defend their preferred brand, and even get hostile. That seems to be the nature of this community (sadly). Well, so be it. There's the data. Shred it as you will.

54
thats great for the type of photography he shoots...but let me see him try to shoot a full wedding with that rig or a heavily scheduled fashion shoot or sports....

mirrorless is a neat technological development but i don't see it ever replacing entirely the convenience of looking through an OVF and being able to see and react quickly to your subject matter.

call me old school....

Aye! I'm playing with the A7r right now, and even though it has some cool features, even a relatively advanced EVF like this is no replacement for an OVF. You can feel the lag...it's not obviously apparent, this is a fast EVF, but it is still there. Movement also has a blurred appearance as you pan around, which is frustrating. The worst thing is the moire...MASSIVE moire an aliasing in the EVF, especially around things like blinds in windows or the deckboards of my deck. It's really bad.

The other thing about an EVF is you have that limit on detail. I can readily see the pixels in the A7r EVF. I can also tell that there is a limit on resolution. It's always been claimed by EVF advocates that the ground glass in an OVF limits resolving power. That may be true, however it doesn't limit it anywhere even remotely close to how limited EVFs are. The difference is massive. I can very clearly tell when my subjects are focused in the 5D III (much better than in the 7D even). I really have a tough time telling what's focused with the A7r EVF...because of that resolution limit.

Another vote from me for OVF. EVF has awful lag and appearance... Apparently, it doesn't bother many. EVF is OK for casual photography.

I've learned that the Sony A7r EVF performance seems to depend on what your pointing at. Not sure why, but there are times when it lags HORRENDOUSLY bad. Part of it is the EVF update speed is related to your chosen exposure...once you get down to large fractions of a second, the EVF lags at that rate. But even at higher frame rates, there are times when panning around when it seems to hit an object or texture or whatever, and that jerks on the lag, and it becomes very visible for a moment or two.

I know a lot of people are fans of EVFs because of what they can do. There is no question this thing can overload you with information about...everything. For me, though, information overload should very much be a secondary concern to high image quality, high frame rate, high resolution, and otherwise being non-intrusive to assisting you in what a viewfinder is designed for: Framing the shot.

I wonder if the low shutter speed issue will always exist. It is probably the single biggest issue...once you get down to 1/30th of a second or slower, it really has a major impact on the EVF frame rate. I got down to 1/4 second at one point...and WOW. I figured the camera would simulate exposure, but it actually seems to really do the exposure you've chosen, even for slow shutter speeds. It really kills the user experience.

55
EOS Bodies / Re: More Talk of an October Announcement of a DSLR [CR1]
« on: September 27, 2014, 12:19:27 AM »
There was the testing being done late summer on a 1D  body with prototype workings inside... That was confirmed... (I believe)

I wouldn't doubt that there is testing being done on prototypes. That can take a while to really get a camera fully tested (especially the way Canon does it.) I think there were rumors about the 5D III and 1D X being out in the field about a year before their announcements.

56
Technical Support / Re: What are the best ND Grads? No circular!
« on: September 27, 2014, 12:14:21 AM »
Personally I prefer the Lee system...it's fairly compact and extremely flexible. Lee, Singh-Ray for the filters. 

Hitech makes some decent filters...but you gotta know what your purchasing. I own a Hitech ND filter that ended up being an "IR" version. I'd purchased it and then ended up not being able to take the trip I'd planned, and never knew that the filter was IR until too late. It wasn't labeled clearly as such, and there were multiple products with very similar names. I'm now stuck with a rather expensive filter that I have no use for. :P I find Lee and Singh-Ray have clearer filter names.

57
EOS Bodies - For Stills / Re: Why haven't you left canon?
« on: September 27, 2014, 12:07:44 AM »
I like Canon for most things. Their L-series lenses are generally great (few outliers, like the 16-35 that aren't the greatest). Their ergonomics are awesome. Their AF is excellent. They have a very broad base of software support thanks to their SDK.

I don't care for the sensor IQ at low ISO. I always want better IQ (I don't like my equipment to limit me in any way...not to say that I'm super good, but limitations slow my progress in becoming a better photographer...and I hate fighting with gear or data.) I particularly don't like Canon IQ for landscapes and macro. It's not an end results thing, it's just a workload thing...more work to achieve any given desired result. I have no intention of jumping ship...but I am very interested in adding to my kit to find a solution for my IQ needs.

58
Well, it's clear this thread will be chock full of sarcasm.  ::)

Have at it, ppl. Real data. That's what it's all about. For those who really want to know what the difference between Canon sensor/ACD IQ vs. Exmore IQ is, I hope the data I provide will help you figure that out. I'll try to provide more example RAW images over the next few days. I don't want to conclude for everyone...just, if your interested, download the RAW images and see for yourself. Draw your own conclusions.

59
When you don't have a flash...then flash cannot be used to solve the DR issue. Which means, more DR IS needed. I do not have a flash for the A7r.

60
EOS Bodies / Re: Just for Jrista: 2014 Market Data
« on: September 26, 2014, 11:22:51 PM »
I fully plan to create some "optimal" exposures, that was actually the entire point of renting the A7r in the first place. It also so happens that this weekend is the last weekend for fall colors in the mountains. It might be raining, not sure yet, but I'm going to try to get some landscape photos, every scene with both cameras, bracketed, etc. I don't have a lot of time to go hunting for awesome landscape scenes, so don't expect any kind of impressive artwork, but I always planned to do a more rigorous comparison between the two.

I've seen lengthy geometric proofs for the fact that a square is the largest rectangle that can be inscribed in a circle, and even lengthier algebraic proofs that 1 + 1 = 2.  At the end of your testing, I'd be quite surprised if don't conclude that the a7R has more DR than the 5DIII and you can push the shadows harder. 

Still, there's value in demonstrating to ourselves that which we expect to be true.  Enjoy!

There are still a number of people on these forums who don't believe 1+1=2. I'm not calling you one of them. Some of these people believe that Canon cameras have the same kind of DR as Exmor cameras. I'll let them draw their own conclusions, I'm kind of tired of having the same old debate, but one in particular did demand that I supply my own data to back up my claims. I told him I would rent the A7r, and do just that...so here I am. Trying to be a man of my word.

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