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Messages - neuroanatomist

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7816
EOS Bodies / Re: DxOMark Sensor Performance: Nikon vs. Canon
« on: October 16, 2012, 04:35:43 PM »
a specialty that I am  special proud of is my medical images .

As someone who taught Gross Anatomy and Neuroanatomy to medical students for 8 years, I appreciate the content - thanks for sharing!

What I don't see is anything that suggests your images have a wide dynamic range in the scene, such that a sensor with a broader DR would be of any meaningful benefit, whatsoever.

7817
Lenses / Re: AFMA'ed the 24-70 mk.ii ... not sure I am loving it.
« on: October 16, 2012, 04:28:51 PM »
So contrast AF is more accurate than phase AF ?

Yes, but slower.  Phase detect uses a separate sensor, and if that sensor or the optics in front of it are misaligned relative to the image sensor, focus will be off (and that why there's AFMA - to correct that misalignment).  Contrast detect uses the image sensor itself to determine focus - nothing to misalign.

7818
Lenses / Re: Lens and filter options for landscape photography
« on: October 16, 2012, 04:09:41 PM »
Here are my questions: 
1. My perception is that use of a Lee or HiTech filter holder and plates will require more setup time and more fragile than screw-on filters.  Do the virtues of a filter holder system, such as the HiTech outweigh the benefits of screw-on filters?
2. If I were to invest in a new body and lenses capable of higher dynamic range to augment my current gear, would this substantially alter the makeup, need for and cost of a filter system?  In other words, is there another equivalent technical solution?

1. Yes, IMO.  The problem with screw-in round grad NDs is they force you to put the horizon in the center of your image - which is probably not where you want it.  A rectangular filter gives you the flexibility to raise and lower the density gradation in the frame.  Note that you can pretty easily hold the filters in your hand for the shot, without the need for a holder system.

2. Theoretically, yes.  Practically, no.  At the risk of having this thread descend into chaos (aka M.R.  ;) ), there are sensors that provide additional mathematically-determined DR based on a calculated noise floor, but that is not the same as real world, usable DR that allows you to distinguish details in the shadows.  But there is another, sort of equivalent technical solution that's much cheaper - HDR.  Done properly with an intent to blend exposures as opposed to tone mapping, you can get very good results.  Probably worth a try before spending $1K on filters.

7819
EOS Bodies / Re: DxOMark Sensor Performance: Nikon vs. Canon
« on: October 16, 2012, 12:48:08 PM »
But it works, and doesn't with a Canon, do you understand the difference?

Next, Mikael, you can explain to all of us how if Kobe Bryant had only been using a Nikon camera, with it's awesome ability to lift even completely dark shots to perfectly usable, noise-free images, he would not have had the problems he experienced here...

Small | Large


We all know about TTL mode, but Nikon cameras, with their perfect sensors, can also shoot in TTLC mode (through the lens cap).   ::) 

7820
Canon can't get the 200-400 F4 L 1.4tc lens to market after more than a year of talking about it and now Sigma has a 200-500 AND its F2.8 ?!?!?!?!?   Canon is so out of touch.

Sigma is so out of touch.  Canon has a 5200mm f/14 lens - where's the cheaper 3rd party version of that one?   :D

7821
It's not new,  been out a while now!

Quite a while, the 'news' is that now you can use one (albeit briefly) for $1K, instead of $26K.

7822
EOS Bodies / Re: DxOMark Sensor Performance: Nikon vs. Canon
« on: October 16, 2012, 08:39:32 AM »
I had NOT paid ANY attention to the Canon/Nikon debate so far. But the pictures posted here by Mr. Risedal make me sit up and take notice.
And take notice is the only thing I can do as I have Mr. X, 3 and whole bunch or lenses already.
I was happily cruising along and then I see these photos... :(

So...one guy takes a few pictures with a specific agenda in mind, deliberately choosing an exposure that is not optimal (and not just a little off - several stops underexposed), and then processes them in ways which may be totally irrelevant to your images, and that makes you doubt your decision to shoot with Canon gear?

7823
I can also come home shattered, creatively drained by a conservative or pernickity client...

I far prefer the term persnickety over pernickity.  Not that I'm either.   :P

Seriously, great feedback and tips!

7824
EOS Bodies - For Stills / Re: Canon EOS-1D X DXOMark Sensor Scores
« on: October 15, 2012, 09:17:07 PM »
While I think that in the aggregate the anecdotal evaluations of Canon's 61pt AF system would generally concur, that it is currently the best available as it produces a higher rate of keepers, and really good keepers at that...

I agree that it's anecdotal.  I'll add my anecdote.  I've got very little experience with Nikon bodies, so I make no attempt at comparison.  I can tell you that I love and hate the 1D X's AF system.  I love it, because it locks on fast, stays locked on, and delivers sharp shots consistently.  I hate it, because it locks on fast, stays locked on, and delivers sharp shots consistently, and that fact combined with the 12 fps frame rate means a harder time triaging my images.   ;) 

Seriously, though - in a burst from the 7D, I could always count on throwing away a few frames as OOF without even looking at them more magnified than reduced to fit my monitor (which is at least a 17" MBP at 1920x1200, and at best a 27" Apple Thunderbolt Display at 2560x1440).  With the 1D X, they are almost always all in focus.

7825
5D MK III Sample Images / Re: Philly Open Air light show
« on: October 15, 2012, 09:00:20 PM »
Here's mine.  I'm from Boston, but was down in PA last month for a 2-day meeting a bit north of Philly.  The night I was staying, I drove down to the city, intending to grab some night cityscapes in the art muesum area.  I had no idea what the display was at the time, turns out it was the final checkout, the night before the exhibit officially opened. 


EOS 1D X, TS-E 24mm f/3.5L II, 2.5 s, f/8, ISO 1600

Ps.  You can see why I like the TS-E lens for architecture and city shots - straight verticals.  :)

7826
Lenses / Re: New 600mm f/4L IS Mk II - availability?
« on: October 15, 2012, 08:55:02 PM »
That, from a company that apparently made people pay the shipping+insurance costs to send $7-13K lenses in for a firmware update?!?  Lol...

7827
EOS Bodies / Re: DxOMark Sensor Performance: Nikon vs. Canon
« on: October 15, 2012, 08:40:45 PM »
...second   "  I can also shoot at ISO 25,600 and print 8 x 10's with general NR and they cannot get those photos" ,   what you saying more points out  that you are looking at  noise reduction nothing else and speaks against measured data , DXO measurements will show the differences
these are from Claff

So, he's talking about ISO noise performance and some aspects of camera performance, in the real world, but you bring out the dead sensor DR horse to beat it some more. Good job.

7828
Lenses / Re: New 600mm f/4L IS Mk II - availability?
« on: October 15, 2012, 07:02:06 PM »
Are price increases coming?  Amazon just bumped prices on 500's at least.  I think this a side effect of quantitative easing.  Dollar is worth less, imports more.

Ouch!  Could be, could be just a blip.  B&H and Adorama haven't increased their prices, yet.  Canon initially priced it at $9500, then increased that to $10500 before release.  Interestingly, Amazon kept their preorder price at $9500 for several months after the increase, while Adorama immediately upped theirs.  I wonder if Amazon honored those preorders...  :-X

Btw I am pretty sure back focusing means that what is in focus is in back of the subject.   Don't think it has anything to do with the buttons.

BTW, I am pretty sure you're wrong about that.  Yes, backfocus can mean (in fact, usually does mean) a focusing error where the camera focuses behind the intended subject.  That's the sort of thing autofocus microsdjustment corrects (and in fact, I just did the AFMA on my 600 II yesterday - it was giving sharp shots prior to AFMA both without and with the 1.4xIII, and sure enough, the values FoCal reported were +1 for the bare lens and -1 with the TC).

But in this case, the context says different, that 'back focus' meant back-button AF (click the link for a Canon article on the subject).  The first mention of 'back focus' in this thread was:

Just for fun I am trying to change to back focusing.


So, do you think Mwindley actually wants to intentionally focus behind the subject to get a blurry shot?  Seems unlikely...

7829
EOS Bodies - For Stills / Re: Canon EOS-1D X DXOMark Sensor Scores
« on: October 15, 2012, 06:48:13 PM »
This is the belief of a math geek who spends too much time with graphs and not enough time with real photographs. Down sampling throws away noise and detail. Dynamic range is the range of useful photographic detail. It is not the simple difference between two numbers on a graph.

Try this: shoot 4x5 Velvia. Drum scan it. Down sample to 10 MP. Did you all of a sudden gain 3-4 stops of shadow detail? No? Hmmm...

+1

Side note: arguments like this are why I hate DR by software analysis. It has zero bearing on the real world. It just leads to paragraphs and paragraphs of irrelevant and pointless theorizing. Shoot a Stouffer transmission step wedge and look at it with your own two eyes. That tells you what you can expect in the real world.

FWIW, one of the things that I do at some point after getting a new camera body is put a Stouffer T4110 on a light box, and use that to determine the 'typical' DR I get across the available ISO settings, and how far I can push that DR using more intensive post-processing of the RAW file.  To me, that's a relevant empirical measure that actually helps me determine exposure when taking real pictures in the real world.  My DR estimates are always less what DxO determines manipulates and calls a Landscape Score.

7830
Yep, me - on The Digital Picture.

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