Messages

91

EOS Bodies / Re: Canon 6D Under-Exposing?

« on: December 05, 2012, 05:44:15 PM »

"The camera’s sensor does not give equal weight to all tones. In fact, your digital sensor is heavily weighted to the brightest areas in your photo. (...) Taken another way, the camera has a fixed number of numeric values for describing the brightness of a pixel. Fifty percent of those numeric values are devoted to the brightest f-stop in your photo. Each successively darker f-stop receives one-half the number of the f-stop ahead of it, until the shadows receive only a small sliver of the total possible values. This is important information, because all detail in your photos is a result of subtle differences in tone and color between adjacent pixels. In the shadows, where fewer values are available to describe these differences, it becomes more difficult to retain details. Underexposing photos drives more of the information contained within a photo deeper into the shadows, causing a loss of detail and an increase in noise (unwanted color impurities) in the photo."
(Taken from Perfect Digital Photography, 2nd edition, hopefully not infringing any copyrights.)

That is correct. If you want to know the reason is quite simple.  Humans see light in an approximately logarithmic fashion (as if we were taking the log (base ~2) of the actual light we see).  (We also hear in a logarithmic fashion as well.)  This is very useful to us since it means we can see when there are just a few photons, and when there are tens of thousands of times more photons per until area of our eyes - and yet it looks to us like it's only a few times brighter.

Sensors are linear, they just measure the approximate number of photons per pixel.  So if your images has 9 stops of dynamic range, the brightest stop has half the the available data.  And the darkest stop only has ~0.2-0.4% of the data.

Exposing to the right (as long as you aren't blowing out the highlights), is a very good idea if you want to have more freedom to play with your images afterwards - since you'll have much more data in the shadows.  Just one stop of "overexposing" will give you twice the shadow detail.

However I digress, and still want to know what's going on with those 6D long exposures...

92

EOS Bodies / Re: Canon 6D Under-Exposing?

« on: December 05, 2012, 03:57:14 PM »

So why is the difference between this 2 shots not that big??
http://img1.focus-numerique.com/focus/articles/1566/canon-6d-100iso-nrstan-big.jpg
http://img1.focus-numerique.com/focus/articles/1541/nikon-d600-100iso-nrstan-big.jpg

Both
ISO100, f/5.6, 1/4s

I'm guessing the Nikon is about 1/3 of a stop brighter here, but it's not a big deal, and it could just be caused by the transmittance of the lenses used - or any number of jpeg engine differences.  So for normal applications, I'd guess we won't see a meaningful difference.

However, I'm a little worried about long exposures.  Interestingly Canon seems to recommend ISO 400 for bulb exposures... I wounder if this is the reason for that?

93

EOS Bodies / Re: Canon 6D ISO tests by the-digital-picture.com

« on: December 05, 2012, 01:55:44 PM »

Looks basically like what would be expected of a 20MP FF sensor with Canon's current tech.

The detail is slightly less than the 5D3, but that's expected since we have lost 2MP compared to the 5D3.  Likewise the noise is slightly less on the 6D, which again is to be expected given the larger pixels.

To be honest, I wouldn't chose one camera over the other based on this difference in noise performance or detail/sharpness - any real world differences will be small at best.

I'm getting the 6D soon, and really all I wanted was approximately 5D3 IQ, the loss of other usability features is to be expected given the price - but at least the IQ is on par.   And I am looking forward to that ~1.5 stop improvement over my 60D!

94

EOS Bodies / Canon 6D Under-Exposing?

« on: December 05, 2012, 12:21:53 PM »

This article suggests that the Canon 6D images are darker by about 1-2 stops vs. other Canon and Nikon cameras with identical settings (at least with long exposures).

http://www.borrowlenses.com/blog/2012/12/is-the-canon-6d-under-exposing/

I'm skeptical about this, and currently the article did the tests only with jpegs - so it's entirely possible this just has something to do with the jpeg engine or jpeg settings.

However, I was wondering if anyone who owns a 6D has seen this issue?  or can confirm this issue does/doesn't actually exist in the RAW files?

95

EOS Bodies / Re: Canon 6D vs 5D MKII (Focusing?)

« on: December 04, 2012, 10:01:13 PM »

Keep in mind that the 5D2 center point will only be cross type with f/2.8 and faster lenses, otherwise it's just a horizontal line sensor.  With the 6D you get cross type at f/5.6 and faster, and improved accuracy at f/2.8 on the vertical line sensor.  That to me will be the biggest difference between the 5D2 and the 6D, since I have a lot of f/4 glass, and I'd like to have a cross type point for those lenses.   

Also I think the f/5.6 type AF points tend to be faster than f/2.8 points for getting the focus into the right general area, so even if you had an f/2.8 lens on the 5D2 and only hit vertical contrast it would in theory be slower than the 6D will be - which can use the f/5.6 to get focus into the right zone, and use the f/2.8 to fine tune.

Also into the realm of speculation looking at the AF diagrams on the Canon website, the AF points on the 5D2 don't seem to extend out from the focus squares as much as the ones on the 6D.  Although I could just be reading things into the diagram...

96

Canon General / Re: What real Pros shoot...

« on: December 04, 2012, 09:30:17 PM »

Interesting that the 2 most popular lenses are the 16-35 and 70-200.  My guess is that they are the most useful for storytelling, and make an efficient combination together.

Most of the photojournalists and wedding photographers I know/have seen work use the 16-35mm and the 70-200 combo.  I think it's largely because 40-65mm tends to be a kind of boring range.  It's the normal range that we are all used to seeing.  16-35mm is great for capturing a subject and their environment, and 70-200mm is great for subject isolation (and getting closer when you physically can't).   It's the combo I would choose to shoot with if I did photojournalism. 

97

Canon General / Re: What real Pros shoot...

« on: December 04, 2012, 09:17:17 PM »

Clearly IQ isn't the most important thing in photojournalism. It's all about capturing stories. Canon is great for this because of the speed and ergonomics. Some of those pictures aren't the greatest compositionally, creatively, etc, but they tell a story. Obviously stats from say studio photographers are going to be totally different.

Pretty obvious stuff, and I don't even know anything.

Even if that is a valid point, Nikon seems dramatically under-represented in the stats.  There must be some other reason for that.  If the photos are largely shot by Reuters staff togs, that may be due to a business relationship between Reuters and Canon.  If you think purely of large sports events - there are not that dramatically more big white lenses than black ones in the photos that circulate the web.

Yeah I suspect there must be a business deal between Canon and Reuters.  There was a time when pro sports shooters were almost all Canon for their superior auto focus (that's one of the reasons Canon became the world leader in photography).  However the difference is marginal at best now days, and I would expect too see more Nikon in that list.

98

Canon General / Re: Is it worth it...for me?

« on: December 04, 2012, 08:38:29 PM »

.
Sorry to rain on the shopping parade, but you need experience far more than you need equipment. You've already got decent picture making equipment; spend your time using that to make the best images you possibly can. Give yourself a year with what you've got. A few suggestions:

1. Get involved with a photo club or some class or group that will critique your work constructively. Typically, they will give you "challenges" to go out and get a particular type of picture so you have to get focused on what it takes to MAKE that kind of image.

2. Limit your shooting to only one lens for a day or week or so. That forces you to live within the limitations of that lens and schools you in the discipline of being challenged by limitations. Photography is nothing if not dealing with limitations. The better you get at accepting and dealing with that, the better photographer you will become.

3. Take pictures relentlessly. Shoot every single day. Maybe for 2013, do a 365 project where you have to take and post a picture every day. This forces you to do the work that makes you better.

4. Do some formal training (reading, classes, online videos, etc.) in the theory of photography -- composition, lighting, optics, etc. I know the more I do this the more it eventually sinks in.

Finally, if you can't resist playing Santa for yourself this month, get one of these two lenses:

EF 100mm f/2.8L Macro. This gives you a tighter portrait capability as well as a new option to try some macro work.

EF 135mm f/2.0L. This provides some reach for the sports you mentioned, and it's great for low light, nighttime work. If you get this, go out and walk around at night taking pictures. Also spend a day doing "headhunting," portraits of everyone you see.

Both of those are L-class lenses and will become part of your kit when you move to full-frame photography. Also, you can get either one for less than $1000US.

Thanks for asking -- a good first step.

+1  This is great advice.

Also if you like taking pictures of people, I can't empathize enough how important it is to learn lighting!   Both how to use external lighting (flashes/strobes/reflectors/modifiers/etc), and how to take advantage of natural light sources.  Strobist.com is a good place to learn more about getting into cheep off camera lighting, but there are many other sources both online and in print.  The best part of lighting is you don't have to spend a lot, since a cheap $100 manual flash will give you the same results as a $600 one in manual mode.  I've had at least 10 times more ROI from lighting, in terms of how much it has improved my photography, than I have from better lenses/cameras.

Specifically I'd advise learning how to light and pose people; there are some amazing things that can be done with a combination of good posing and good lighting.  Want to make a person look lighter and thinner, or stronger and larger?  Want to create an atmosphere, or a specific mood?  No camera will do that, but there are lighting/posing/composing tricks that will.

Now I'll admit I enjoy fancy equipment as much as the next person (I'm buying a 6D this week, and I own the 100mm f/2.8L macro and I love it for portraits and macro).  And I'd love to own an 85mm f/1.2L, a 135mm f/2L, and a 5D3 someday.  It's fun to shoot with awesome equipment.  And if you have the means and will enjoy using it, why not.  However, it won't make your photos automatically better.  Only a combination of experience and knowledge will do that.  Looking at your photos you are off to a great start already.

Best of luck, and keep having fun taking pictures!

99

Canada / Re: 6D arrives in Canada?

« on: December 04, 2012, 06:00:02 PM »

Henry's is saying on their front page that they now have stock.  However, I've yet to receive a call from my local store that they have it (I know my sales guy there will set one aside for me as soon as it comes in).  So I'm guessing they got it at their warehouse, and it's in the process of making it out to the stores.

100

Canada / Re: 6D arrives in Canada?

« on: December 02, 2012, 01:08:24 PM »

I have one on order from Henry's, I talked to them on Friday and they said they weren't sure when it was coming in.  They also mentioned that Canada tends to get stock a week or two after the US.  Hoping that since the stock at B&H isn't selling out we'll see the camera here by Friday or so.

101

EOS Bodies / Re: More 6D sample images - with RAW files.

« on: December 01, 2012, 03:56:10 PM »

a shot that needed +4ev raised in the low tones was not necessarily broken by any means, it just means that it had lots of DR, enough with that nonsense

Agreed. I shoot a lot of landscape/architecture at ISO 100, and there are lots of times I need to push shadows by quite a few stops - maybe not 4 stops all the time, but pushing by 4 stops gives a good idea of how it will break down, or not.  Plus if you are shooting any photojournalism type stuff, sometimes you miss the getting the right exposure even in good light, and have no choice but to push the image.  That's what make's the Sony/Nikon sensors so great at the moment - they have more DR, and don't "band" when you push them.  I'm still sicking with Canon for the time being, but I would love it if they could improve this weakness of banding + low DR.

102

EOS Bodies / Re: More 6D sample images - with RAW files.

« on: December 01, 2012, 02:57:20 PM »

It may just be me, but I think Canon has improved their banding issues. 

The images on the left hand side have no NR, and have been pushed by 4EV.

The images on the right hand side have base 50/50 NR, and have been pushed 4EV.

5D3 images are on top, 6D images on the bottom.

Done using Capture One.

Notes:  The 5D3 images were slightly darker than the 6D images with no exposure compensation.  The difference was small enough however that I don't think it would make a huge difference to the banding.

I'm looking for some 6D RAW files with a black sky to really push this test, but I haven't found any yet.

Of course this is still a pre-production camera, but I think things are looking good.

What do others think?

Edit: It's easier to see the difference if you download the full image.

103

EOS Bodies / Re: More 6D sample images - with RAW files.

« on: December 01, 2012, 01:42:54 PM »

Very nice. I would say the difference is about 0.7 stops better for 6D (comparing ISO 12800 to 25600). Yummy!

I just had a look again, and the 6d images are softer - that maybe because...

• the pre-release raw converter is not up to it
• the (preproduction!) 6d trades in a little sharpness for less noise, maybe because Canon doesn't expect 6d owners to shoot with sharp lenses anyway, but in low light :-p
• some problem with the lens (50/1.8...)
  

The video samples of the preproduction model were said to suffer from the same thing. Btw it isn't as obvious at higher iso levels since the noise creates an impression of artifical sharpness, for the softness look at iso 800...

I guess we have to wait for raw samples from the *final* retail model with a more recent raw converter, I hope it shouldn't take long since the the 6d is already sold.

From what has been learned from the lensrentals posts, I'm guessing the 50 f/1.8 copy they used just doesn't preform as well on the copy of the 6D they got.  The other issue is the light has moved locations between the tests, so it's possible that is effecting the perceived sharpness.  It could even be that they didn't nail the focus as well, or it could even just be the effect of extra MP on the 5D3.  It may also have nothing to do with the sensor or lens and just the anti-aliasing filter being a little on the strong side.

Overall though, the difference really isn't big enough for concern.  If you really need the sharpness, the D800 is really the best option now.  For me, the difference is too small to matter in my applications.

104

EOS Bodies - For Stills / Re: 6d Reviews

« on: November 30, 2012, 08:41:48 PM »

They aren't complete reviews by any means, but LensRentals/Roger Cicala has both taken one apart and tested the AF center point:

http://www.lensrentals.com/blog/2012/11/a-quick-6d-af-test
http://www.lensrentals.com/blog/2012/11/a-peek-inside-the-6d

Sad, was hoping they'd super charge that center point, but I guess you get what you pay for (even if the cheaper option is still kind of pricey).  However at least making the point huge for low light didn't lower it's accuracy, vs. other lesser Canon's.

105

EOS Bodies / Re: More 6D sample images - with RAW files.

« on: November 30, 2012, 06:15:25 PM »

Opened with capture one 7.0.1 (preliminary support)

Thanks for posting!  It does look like the 6D is visibly a tad better than the 5D3.  However I'm guessing no more than 1/3 stop at best (likely just from the slightly larger pixels).  Still good to know Canon hasn't skimped out on the 6D sensor.   Of course it has been noted this is a per-production camera, but I don't think  anything is likely to have changed.