November 23, 2014, 05:32:45 PM

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Messages - jrista

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46
Photography Technique / Re: High shutter speed, low aperture but what ISO?
« on: November 12, 2014, 03:33:50 PM »
I totally agree with this.

Well, I disagreed with pdb, so maybe you agreeing with me was to be expected :-p. But I still feel I might have finally got something right around here :-)


Oh, no! I agree with you because I agree with you. Despite how some may portray me, I am not petty like that. I have no interest in agree with anyone as a means of disagreeing with someone else. If I disagree with someone...well, I disagree with them openly (I think everyone on these forums knows that by now.)


I don't know you as someone who gets things wrong...your very knowledgeable in my book. You are a great source of ML knowledge in particular, and I think that's great. I think your spot on with your comment here about ISO as well.


I always find it interesting that somehow some concepts, which really don't seem difficult or complex to me, are often portrayed as "too difficult" for the average photographer. As far as I am concerned, if someone is using a DSLR day in and day out, then learning a little bit about the nuanced behavior of ISO settings can only help them produce better results. Why hold knowledge back?


You are absolutely correct that pushing ISO higher and higher to get a "correct" exposure may be costing the photographer dynamic range. Dynamic range is just as important at higher ISO as it is at lower ISO. These days I think dynamic range is as important for my bird and wildlife photography as it is for landscapes. Ever photograph a chickadee? Brilliant bright white paired up with dark blacks. Doesn't really matter how you approach a subject like that...something, somewhere, is going to suffer. It's difficult not to clip the highlights of those little birds (assuming you want any amount of detail in the black feathers...otherwise you just block up the black feathers into pure black, no detail at all...personally, I don't like that option), especially when you usually need shutter speeds over 1/1000s to freeze their constant motion. Sometimes, underexposing at a lower ISO is necessary to protect those highlights, and still get the shutter speed you need.


So, I really do agree with you. And I agree with you because I think your correct. ;)

47
Like I said...not revolutionary and likely irrelevant for dSLR/MILC.

people said the same about BSI sensors.
they will only be used in smartphone and tiny sensors.

or exmor.. how many said that´s useless.

well a few years later everyone wants exmor sensors.

 
 
What people said about backlit sensors in 2008 were that it was more effective for small sensors, but with a few years of development, that might change.  Its still true, as the sensor gets larger, given the same pixel sizes, backlight technology is not as useful.  For very high MP sensors where there is not enough room for wiring on the front side, than moving the wiring to the back allows for larger photosites which is a definite help. 
 
So, yes, years later, BSI technology is finding its way into larger sensors each generation.


It's already found it's way into a 1.5x crop APS-C sensor with Samsung's NX1 camera.

Yes, Samsung was one of the early companies to start working on BSI.  I think that we will eventually see it even on MF sensors when the MP count climbs so high the the wiring is causing a issue.
 
I think that the 35MP point on FF starts to see a slight advantage, and at 50-60MP, it might be enough to make a big difference.  I hope Canon does it before then, even a small reduction in noise helps.


If Canon is moving to layered sensors, I believe they will be BSI. The more recent patents we have seen from them regarding layered sensors showed BSI designs.

48
Quote
......
– Records 2K with 16,000 frames per second.

So a 7D2 at 2K 60Hz video cranks out 440Mbytes per minute.... At 16000 fps that becomes 117,333Mbytes per minute or a mere 1,956Mbytes per second. My 32Gbyte CF card would hold 16.3 seconds worth of video....

I think I need a bigger card :)


Are those values for RAW video? Generally speaking, you can gain massive compression ratios with video, and at such high frame rates, the differences between frames are going to be quite small, so I would expect the compression ratio to be even higher.

49
Photography Technique / Re: High shutter speed, low aperture but what ISO?
« on: November 12, 2014, 01:21:07 PM »
Never intentionally underexpose and then try to raise exposure in Lightroom.

I disagree because...

Always choose higher iso and brighter exposed shot. Dealing with well exposed noise is much easier than dealing with underexposure and noise.

... unless the iso value you're dealing with is just digitally amplified (usually above 3200 or 6400, varies among models) - in that case, increasing iso just cuts away dynamic range.

One additional benefit of underexposing a bit on lower iso is highlight safety in varying higher contrast outdoor light. If your camera metering misses with a "properly" exposed setting, the whites are blown. ymmv with what camera metering you use, but my 6d is dodgy so I'd rather play safe.

The problem esp. with my 60d's crop sensor is that higher iso values destroy color accuracy, so personally I rather underexpose 800 a bit than raise to 1600 or even 3200. You can always try to get rid of noise in post, but preserving colors after the fact is difficult. Again ymmv depending on the scene and your camera model.


I totally agree with this. There is a point of diminishing returns as far as pushing ISO goes. Once you hit the read noise floor, using higher and higher ISO settings is going to start severely impacting your DR, for practically zero gain on the noise front. Technically speaking, using ISO 12800 is better than using 6400 because your still amplifying the signal before read noise is introduced, but on current cameras read noise at those ISOs is usually <3e- anyway, so the difference between ISO 6400 and 12800 is by far the loss in dynamic range (by orders of magnitude). You could easily shoot at ISO 6400 and lift in post, and not notice any difference as far as shadow noise goes...however if you clip the signal at ISO 12800, your better off using ISO 6400.

50
Like I said...not revolutionary and likely irrelevant for dSLR/MILC.

people said the same about BSI sensors.
they will only be used in smartphone and tiny sensors.

or exmor.. how many said that´s useless.

well a few years later everyone wants exmor sensors.

 
 
What people said about backlit sensors in 2008 were that it was more effective for small sensors, but with a few years of development, that might change.  Its still true, as the sensor gets larger, given the same pixel sizes, backlight technology is not as useful.  For very high MP sensors where there is not enough room for wiring on the front side, than moving the wiring to the back allows for larger photosites which is a definite help. 
 
So, yes, years later, BSI technology is finding its way into larger sensors each generation.


It's already found it's way into a 1.5x crop APS-C sensor with Samsung's NX1 camera.

51
The guys at image sensors world were thinking the report was faked:


http://image-sensors-world.blogspot.com/2014/11/rumor-sony-to-introduce-active-pixel.html


Wonkey voltages and such.


They also seemed to believe it was just another standard layered sensor design, nothing particularly out of the park as far as electronic movable filter arrays or anything like that. The guys who comment on ISW very often ARE sensor designers...so I would take their word over some random report at sony rumors any day. :P

52
EOS Bodies / Re: Canon 7D Mark II - DXO, Tony Northrup, and You
« on: November 11, 2014, 03:18:02 PM »
He really said that? Yikes...that's nuts.

Not really, no.  The context makes it pretty clear they are saying there is no reason to switch from Canon to Nikon unless you need the absolute best IQ.  The wording was clumsy but you'd have to really have an axe to grind to think they were dogging on the 5DIII.

Will the CR admins delete this comment too?  Lets find out!

They also deleted my comment praising your fairness and eloquence.


I think it was the, um, rumphurt stuff. :P

53
Canon General / Re: Hello everyone!
« on: November 11, 2014, 01:06:58 PM »

Welcome aboard, pcdebb. Welcome to the Canon side. ;) It's whiter over here.


Jrista,

Terrific write-up! Definitely going into my files.

Thanks for the time and effort.

FWIW, did I miss something, or was mention of "STM" lenses absent?


STM, USM, and all the various acronyms that often get attached to lenses was something I skipped. I guess I could get into that, but I covered all that a long time ago here:


http://photo.stackexchange.com/questions/496/what-do-all-those-cryptic-number-and-letter-codes-in-a-lens-name-mean/508#508

54
Canon General / Re: Hello everyone!
« on: November 11, 2014, 10:51:27 AM »
I know it sounds wierd, but the camera feels better in my hands.  I was out and about a few weeks ago, and a lady and her friend were out as well.  She asked me to take a pic of them with her Canon.  I was impressed.  I dont know if it's build quality or not.  I've been looking at Canon gear for a while anyway but just never acted on it.  I'm already comfortable with the menu layouts of the camera, I can find everything and change it quickly.  I dont want to say Nikon is cheaply built, but it felt that way in comparison.


You will probably find that one of the key things that keeps people using Canon is the ergonomics and button placement. Many of us desperately want the sensor IQ of a Nikon, but are unwilling to really give up our Canon bodies. Personally, I think Canon DSLR body ergonomics and button placement are at the pinnacle of DSLR design. They fit my hands perfectly, have ever since the 7D. It's just one of the thing that I think Canon does better. (And trust me, I am the first to admit Canon has their faults...there are some things about Canon I just downright do not like.)

55
Canon General / Re: Hello everyone!
« on: November 11, 2014, 01:37:41 AM »
For maximum upgrade compatibility, only use true EF mount (full frame) lenses. Those are compatible with pretty much everything, including APS-C and EOS-M cameras. The other sibling mounts, EF-s and EF-M, are far less compatible, and if you ever move from APS-C to FF, any EF-s lenses you get will not work on the FF body.


It should also be noted that all L-series lenses are strait up EF full-frame lenses, and therefor always compatible with all the sibling EF mount variants.

56
It IS compatible with both the 1.4x and 2x teleconverters.


Sure, but what camera body is going to AF at f/11?

57
Canon General / Re: Hello everyone!
« on: November 10, 2014, 11:59:33 PM »
Welcome aboard, pcdebb. Welcome to the Canon side. ;) It's whiter over here.


First off, L-series lenses are the Luxury line. Anything with a red band is an L-series lens, and they have the best build quality, glass quality, and all the bells and whistles. Many of Canon's L-series telephoto lenses, zooms and primes, are white...kind of an iconic look, but pragmatic as well (the lighter color reflects more heat out in the sun, resulting in slower expansion of the lens.) So, if you want the best glass, you want L-series glass.


You should also learn the difference in mounts. Canon has a few now. At their core, they are all EF mount, or Electronic Focus. The EF mount is a full frame mount with a full set of electronic contacts that support full communication between lens and camera. Derived from the EF mount is the EF-s mount. This is the short-backfocus version of the EF mount. EF-s lenses are only compatible with APS-C DSLR bodies, or crop bodies. I'll get to the naming system of Canon's DSLRs in a moment (it's very logical, which should be a nice change from Nikon's oft-changing and sometimes confusing naming scheme.) When buying lenses, it is very important that you make SURE you don't buy EF-s lenses for use on a full-frame body. The design of EF-s lenses makes use of shorter backfocus, often protruding into the mirror box a short ways. This is possible due to the fact that the mirror in a crop body is a lot smaller, allowing some clearance room for the extra protruding length of an EF-s lens. Finally, there is the EF-M mount, or mirrorless mount. EF-M lenses are only compatible with Canon's mirrorless EOS-M line of cameras, which...entirely lacking a mirror...have a much shorter flange focal distance.


All EF lenses, including EF-s and EF-M, use the same basic bayonette mount. This makes the whole system generally compatible. For example, you can use a simple passthrough adapter to attach EF-s and EF lenses to EOS-M bodies.


When it comes to Canon ILC bodies, Canon's naming scheme is pretty simple. There are several key camera series, usually denoted with xs and Ds. :) They are as follows: xxxxD, xxxD, xxD, xD. The four-digit, or xxxxD, models are the low end entry level DSLRs. Like the Canon EOS 1200D. (Oh, side note...EOS stands for Electro-Optical System, the overarching technology brand for Canon's cameras.) The three-digit, or xxxD, models are the standard entry level DSLRs. Like the Canon EOS 750D. It should also be noted that these two lines, the low end and standard entry level DSLRs, have alternative names. Together they make up the Rebels, or in Japan the "KISS" models. They usually have alternative names, such as in the US, the 1200D is also the Rebel T5, while the 750D is the Rebel T6i. For the most part, I think Canon users just refer to them by their common model number, like 1200D or 750D.


The two-digit, or xxD, models are the midrange semi-pro level DSLRs. Like the Canon 70D or 60Da. In the semi-pro line, Canon periodically releases "astrophotography" versions. The first was the 20Da, and the current is the 60Da. These models use a special filter stack over the sensor that has weaker IR filtration, increasing the "Hydrogen-Alpha" sensitivity of the camera, making it more sensitive for imaging the emission nebula that permeate the galaxies of the cosmos.


Each of these lines of cameras tend to have their own general size ranges as well. The xxxxD and xxxD lines tend to be the smallest, with the xxD line gaining a moderate bump up in size. When you get to the professional lines, the xD lines, size jumps up again. As far as generation-successive naming goes, Canon's models all increase by a certain sequence count each new generation. So, the 1200D will upgrade to the 1300D in the next generation (increase by 100), the 750D will upgrade to the 800D (increase by 50), and the 70D will upgrade to the 80D (increase by 10).


This is Canon's lower end series of DSLR cameras. They are all APS-C (cropped sensor frame) DSLR bodies, and therefor are all compatible with both EF and EF-s lenses. These cameras are all incompatible with EF-M lenses.


Canon's professional-grade models are organized a little differently. All of them are grouped into the xD models, however instead of there simply being one line of "pro-grade" cameras, there are a few. There is the 1D line, the 5D line, the 6D line, and the 7D line. The first three are all full-frame cameras, while the latter is an APS-C camera.


The 1D is Canon's premium DSLR offering, the true "professional" line, bringing with it all the top of the line features with a top of the line price. The 1D line bodies are huge, including an integrated grip, bigger batteries that deliver more power for faster AF, and a whole host of other fancy features. The 5D line is Canon's workhorse professional-grade line of cameras, the high volume higher end model, used by countless professionals in the wedding, portraiture and journalism fields, as well as by landscape photographers, bird and wildlife photographers, and pretty much any kind of photographer who needs a highly capable, general purpose DSLR.


The 6D line is the "entry level" full frame camera in Canon's lineup. It brings the full frame sensor to a more "affordable" body in the lower $2000 range (street price well below that.) The 6D takes a hit to a lot of the features...it uses a simpler AF system, lower frame rate, fewer custom functions, etc. The 7D line is Canon's premium APS-C body. It's relatively unique in the DSLR world, combining high end features like ultra fast frame rate, highly advanced AF and metering system, and lots of custom functions and customizability in a smaller and more compact, agile body than the 1D line. The 7D comes at a prime price in the "affordable" range, bringing true action and sports tracking quality to the masses (and for less than $2000.)


Because the xD lines are single digit, successive generations do not increase numerically. Instead, Canon has the "Mark" system for denoting generations. Such as the 1D Mark IV, the 1D X (Mark X or Mark 10), the 5D Mark III, the 7D Mark II.


The 1D, 5D, and 6D lines, being full frame cameras, are only compatible with Canon's EF lenses. They are incompatible with EF-s and EF-M lenses. The 7D line, being APS-C, is compatible with EF and EF-s lenses, but is still incompatible with EF-M lenses.


So, now that you know how Canon's system works, how each camera model is named, and what mounts they are compatible with, you should be equipped to NOT buy the wrong lens. ;)


As for what lenses you "should be looking at", assuming you only do landscapes, then there are a variety of options. First, you have the 16-35mm and 24-70mm lenses. These are generally your "wide angle landscape" zooms. You can find these zooms in both f/2.8 and f/4 varieties, and which one you choose will ultimately depend on budget and goals, and whether you need IS or not. If you generally stop down for your landscapes, you probably don't need the f/2.8 versions of either. The EF 24-70 f/2.8 L II is one of Canon's sharpest zoom lenses in their lineup, and produces excellent quality wide open. If you are just going to stop the lens down to f/8 or f/11 for a landscape photo, you might not want to spend the extra money for the f/2.8 version. The same generally goes for the 16-35mm lenses, which also come in both apertures. The older EF 16-35mm f/2.8 L II lens uses a poorer optical design, and as such suffers fairly heavily in the corners. The newly released EF 16-35mm f/4 L IS has been rated as one of Canon's sharpest zooms, and would make for a superb wide angle landscape lens. It also has image stabilization (IS), so if you need to hand-hold it for any reason, it gives you stops of improved hand holdability.


There are also some other options for landscape photographers. Canon has a bunch of wide and ultra-wide angle primes. Like the EF 14mm f/2.8 L II, EF 24mm f/1.4 L and EF 24mm f/2.8 IS, etc. Canon also has some unique options that can bring a lot of interesting capabilities to lanscape photographers. The TS-E (Tilt/Shift Electronic) manual focus lenses, the TS-E 17mm f/4 L and TS-E 24mm f/3.5 L II, are a couple of relatively unique options to the Canon system. They are not entirely unique, as there are tilt/shift lenses for the Nikon system. However the 17mm TS is currently unique to Canon's system, and offers one of the widest tilt-shift lenses available for DSLRs. Both lenses are extremely sharp, with the TS-E 24mm being one of Canon's sharpest lenses, period. With a tilt-shift lens, you can adjust the plane of focus, and get the entire depth of your scene, from ultra close foreground objects to ultra distant background scenery, in very sharp focus at non-diffraction limited apertures (i.e. at f/4, if you wanted to...no need to stop down to f/11, f/16, f/22 for DOF.)


Canon has plenty of other lenses, including other totally unique items like the MP-E 65mm f/2.8 1-5x Zoom Macro. They have all the standards, like your 50mm, 85mm & 135mm fast (and ultra fast) portraiture primes, your 70-200mm zooms, and a whole range of other lenses, extending out to the "Great White" L-series ultra high end telephoto and supertelephoto primes (200 f/2, 300 f/2.8, 400 f/2.8, 500 f/4, 600 f/4 and 800 f/5.6), in case you need super fast or ultra long reach.

58
I don't know about your lenses or shooting circumstances, but for me lifting the +0.5lv af limit of the 60d (that's not very dark esp. with f4+ lenses) is a merit on its own.

FWIW, I measured +0.1 EV with my Sekonic 558 on an indoor target i was using for some tests.
with the 100-400 L mounted and stroked out to the 400mm end, the 60D and the 7d2 were both able to AF, and oddly, the 60D did it subjectively faster every time.
I think there may be some minor issues the 7d2 needs to have addressed with some firmware tweaks.
I'm pretty sure 7d2 would deliver better IQ than the good old, non-ML-equipped, 60D.


Well, is it possible the 7D II has firmware that is explicitly designed to throttle AF speed on lenses that need it to happen more slowly? The old 100-400 has it's issues...mine seemed to hunt more than I ever liked. Maybe they are forcing a slower AF speed now to limit hunting. Have you tried other lenses?


Also, is the 7D II consistently accurate and precise? I mean, is the issue just that it's slow, or is it actually misfocusing? The thing I'm most interested in is whether Canon's new 65pt AF system inherited the 19pt AF system's inherent "jitter"...in that, frame to frame, it would always adjust focus ever so slightly, resulting in some frames just being enough OOF that you could tell...then popping back into perfect focus the next frame.

59
EOS Bodies / Re: Canon 7D Mark II - DXO, Tony Northrup, and You
« on: November 10, 2014, 08:13:49 PM »
I think that he makes excellent videos and I do not understand that bashing here

In the first Northrup video I watched (which immediately became the last and only one I'll watch), he and his co-host basically concluded that the Canon 5D Mark III was probably ok for non-pros posting their pictures to Facebook.   Really, really excellent.  ::)


He really said that? Yikes...that's nuts. I have my issues with the 5D III, and there are things about it that BUG THE CRAP out of me...but I have no doubt it's a professional grade DSLR.

60
Lenses / Re: Is the new 100-400L II going to be a push/pull after all?
« on: November 10, 2014, 07:52:05 PM »
The new 100-400 II still has the focus tension/locking ring that the push/pull design had (so I can understand why you might think the lens was a push/pull design), however it is NOT a push/pull design itself. My guess is that Canon included the tension ring for the same reasons...that the weight of the lens would change focus if you pointed it up or down enough.

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