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Messages - dgatwood

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EOS Bodies - For Stills / Re: clown* photographer
« on: Today at 03:32:32 PM »
The poorest cameras of today are better than the cameras of decades ago.

Cameras, yes.  Lenses, no.  The poorest cameras today have fixed-focus wide-angle lenses.  That's what holds back iPad/iPhone photography most, not the sensor.  That and the lack of a built-in tripod mount.  The sensor causes problems only when the lighting is bad.  :)

EOS Bodies - For Stills / Re: LP-E6N Backwards Compatible
« on: Today at 03:27:16 PM »
Also, I bought mine shortly after I bought my 6D, so there's some possibility that Delkin fixed a bug in the hardware's handling of certain cells during the 1.5 years between when that review was written and when I bought mine.

EOS Bodies - For Stills / Re: How to differentiate crop vs. FF
« on: October 23, 2014, 06:23:14 PM »
Crop vs. Full frame.

As a 6d owner - my first full frame- im very unimpressed at its low iso quality. There is no 3d-ish POP that i have seen in so many 5d2/5d3 images over the years - image quality that i could easily see was not reproducible on my crop cameras.

To these ultra pixel peeping eyes, the 6d is only slightly better at dynamic range than my t2i.  High Iso handling is generally FANTASTIC, which is why i figure the low iso takes an image quality hit. Low light photography is a whole other ball game compared to my crop bodies.

So while i enjoy my 6d, its nowhere close to the full frame experience i thought it would be. Still dreaming of a 5d3 and non-ancient AF.  :(

Really? From what I've seen, 5D2-3 and 6D images side by side look almost identical :).

All else being equal, the 6D images are slightly better, because they have less banding noise in the shadows.  Of course, that usually isn't obvious until you boost them by a couple of stops.

If one has seen and admired a '3D-ish POP' in 5DII/III images taken by others over the years, but doesn't see that quality in one's own 6D images, I suppose "it's the camera" is one possible explanation.  It's certainly a more palatable one than the far more likely and rational reason for the discrepancy.

There are three likely reasons: the lens, the lighting, and differences in post-processing choices.  The camera shouldn't matter much at all, except insofar as it affects the choice of lens....

EOS Bodies - For Stills / Re: LP-E6N Backwards Compatible
« on: October 23, 2014, 06:13:02 PM »
... Delkin dual universal battery charger ...
And no idiotic chip checks.  :)

Unfortunately neither the Delkin nor the Pearstone/Watson dual chargers seem to be able to (reliable) charge Original Canon LP-E6 (or other Canon batteries) - just read the user reviews on BHPhoto or amazon.

I've been using the Delkin as my primary charger with LP-E6 batteries for almost a year now.  I basically never use the factory charger, because it charges only one battery, and my grip contains two.  I haven't had any problems whatsoever with it.

I can't imagine what could cause the problems described by the one review, other than perhaps the battery's charge indicator not getting recalibrated as the cells degrade (in which case the problem would be purely cosmetic—the battery really *does* have less capacity, and the Canon charger's recalibration would just hide that fact).

The complaint I've seen about the plates being a little loose is a valid one.  I'm tempted to add a layer of electric tape to make it more snug.  But charging failures?  No.  Maybe with really early LP-E6 batteries, but not with the 6D version or later versions.

Third Party Manufacturers / Re: How Strong is a Sony Lens Mount
« on: October 23, 2014, 05:55:21 PM »
What I care about is that my lens not disconnect from my camera body at the wrong time.  This happened to me with my 5D3 and 500mm f/4 with 1.4x III extender.  I connected the lens to my Black Rapid with my hand wrapped around the foot of the lens in order to stabilize it while walking.  Nevertheless, my 5D3 disconnected with the lens and fell on the concrete (my RRS L-bracket took the hit).  Somehow my 5D3 loosened and rotated off the lens while I was walking along.  I have no clue how it happened.  Anyone who thinks Canon is not prone to mount-related issues is mistaken.

Your hand or some part of your clothing or the strap depressed the lens release button.  That's a 'mount-related issue' only in the wetware sense (i.e. you).  I speak from experience, in my case it was the belt loop of my jeans when carrying the 5DII with 70-200 II after mounting the 2xII.  The TC altered the balance of the rig and I didn't change the position of the 1" clamp connecting the BR strap to the lens foot.  FWIW, my camera was fine although when I checked AFMA I found the values for all lenses had shifted ~10 units negative.


That's a issue that has been around for Bayonet mounts since they were first invented.  Push the button or pull a lever, twist the lens, and it comes off.  Threaded lenses were better in that respect, a lot of people preferred the breech lock system, but the same thing could happen, just not quite as easily.

I'd think that a secondary safety lock might be useful for those who are carrying the camera on a type of strap that lets that button get pressed unknowingly.  The standard Canon neck strap cause the accidental release, it merely puts my neck and back into agony.

Maybe someone could convince Fotodiox to make something like that, or a kick starter project.  I'd have to have funding to buy one each of all the Canon DSLR's and lenses in order to test it out  thoroughly.  I guess I'd need to try it with all the carry straps as well.

I've a couple of ideas to do it.

There's a much simpler way to handle that problem: glue a security eyelet to the side of each lens, attach a short strap with a carabiner, and when you attach the lens, clip the carabiner to your camera strap.  That way, even if it detaches, the lens won't fall very far.

EOS Bodies - For Stills / Re: LP-E6N Backwards Compatible
« on: October 22, 2014, 03:30:31 PM »
I keep thinking, Canon sells battery grips, why on Earth don't they sell chargers that can charge two batteries simultaneously?

They do...for the 1-series bodies.  :P

For other Canon dSLR batteries, check out the hähnel ProCUBE.

Or, for a more flexible two-battery charger, take a look at the Delkin dual universal battery charger.  You can get various charging plates for different batteries.  I have plates for the LP-E6 (for my 6D) and for the NB-2LH (for my old XTi backup body).  I could even get a plate for my 300D's BP-511 if I wanted one.

And no idiotic chip checks.  :)

EOS Bodies - For Video / Re: 6D video for sports
« on: October 18, 2014, 09:40:11 PM »
Also, since the 6D doesn't have the AA filter there is tons of moire. Honestly, it makes a lot of footage look like crap  :-\

Unfortunately, you're wrong - the 6d does have an aa filter that also makes still shots softer, the moire is the result that downscaling to hd resolution cannot use "pixel binning" like on the 22mp 5d3 but needs to interpolate some of the 20mp lines - and the 6d is very bad at doing this.

They could just as easily do exact pixel binning on the 6D.  They would just have to crop the image first.

  • At 720p, the sensor is 4.275 pixels per output pixel, so you could throw away the outer pixels (use a 1.07x crop factor) and then scale 4:1.
  • At 1080p, that approach would be more problematic, because the ratio is 2.85:1.  Making it 2:1 would be a 1.43x crop factor, making it almost like shooting video on a crop body in terms of what it does to your field of view, but it still might be worth it if the results had less moiré.

With that said, it isn't just a question of binning.  If you just bin a bunch of pixels together, you'll get more moiré, not less.  You have to do the binning in combination with a digital low-pass filter that effectively does the low-res video equivalent of what the antialiasing filter does for stills.  The real question is whether the 6D has the CPU power to do the low-pass filtering.  If it doesn't, then binning won't help.  And if it does, then someone could probably come up with a better algorithm for non-integer downsampling than whatever the 6D currently uses, resulting in video that is comparable to what you'd get with binning, but without the field-of-view change.

I'd much rather see Canon bake the continuous gyroscope data into the EXIF tags and leave the processing to computers that actually have the CPU power to handle it.  Ideally, they'd downsample the video footage and compress it at somewhere around 1280p instead of 1080p, leaving a nice margin so that when you process the footage, you'd still have 1080p, and they would show you the center portion of that footage so that in the absence of massive correction, what you see would be the final, cropped output.

That scheme would also have the advantage of being able to correct more robustly by virtue of being able to look at the entire set of data rather than trying to guess whether that was a shake or a deliberate pan.  And when compensating for a particular shake would cause a black border, if you're working with the data all at once, you can retroactively adjust the center of previous frames to avoid the problem, or at least smooth it out in ways that you cannot accomplish in real time.

And just to clarify, lens IS does do this, but it isn't really designed for video; it is designed for holding the image dead still.  For video, it is suboptimal, because that usually isn't what you want.  You want motion to be smoothed out, not eliminated.  Otherwise, when you hit the limit of its range, you get a nasty jerk in the picture.

As for "no downsampling", you're downsampling anyway.  Just about nobody shoots RAW video.  And with the 16:9 aspect ratio, you're throwing away pixels on the top and bottom no matter what, even after downsampling, because you don't use the full height of the sensor.  Those pixels could be made available for post-processing... essentially for free, without even needing to crop, though you would probably want to crop a little bit to accommodate horizontal shake.  And because vertical shake usually has the highest amplitude, that's a real win.

I don't think people get offended, they just disagree and want to say why they disagree. Nothing wrong with that.

I think some of the posts on this website go a little beyond simply disagreement.

Name calling, personal insults, and ad Hominem attacks are not disagreements.  ;)

Also, just because someone publishes somethign that I disagree with, does not mean that I have to respond.   I disagree with a lot of stuff in life and I don't respond.  ;D

But... but... but...

(xkcd #386)

Lenses / Re: Why are Cine Lenses so expensive?
« on: October 15, 2014, 03:10:18 PM »
Another reason Cine lenses are more expensive: Calibration.

Roger Cicala of lensrentals.com in another post (not the one quoted earlier in the thread) was writing about sample variation and how shocked the average photographer would be at the differences between even high end pro lenses right out of the box.    Since as part of their business, they routinely re-align elements and test the lenses very carefully, he pondered how much effort would go in to making sure every lens is perfectly tweaked before it leaves the factory.

He reckoned it'd about triple the cost of the lens.  Which, he noted, is about what Cine lenses go for...

That might be true if you have a person do it.  If you design an automated calibration rig that tunes each lens precisely before final assembly, it would be a fixed equipment cost that, amortized over millions of lenses, should have minimal impact on the cost of the lens.

The big cost of Cine lenses is lack of amortization.  All of the design is spread across a much smaller number of lenses, because most people don't demand parfocal lenses for still photography (even though they really should).  If Canon designed every lens to be parfocal, the impact of parfocal designs on the cost of lenses should also be pretty small.  The same goes for other design decisions, such as lack of focus breathing.

So basically, they're expensive because not many people buy them, and not many people buy them because they're expensive.  The day someone new enters the market and decides to make all their general-purpose lenses be up to Cine lens standards, Canon will suddenly find ways to bring the cost down.

EOS Bodies / Re: EOS 6D Mark II to Move Upmarket? [CR1]
« on: October 14, 2014, 06:46:42 PM »
The 6D, while completely capable of capturing beautiful images, has some serious limitations for certain types of photography. That is not to say it is a bad camera, just better suited to other types of photography.
Sure, a better AF system would be better for sports, but I'd hardly call it seriously limited.  I've used a 6D to shoot sports (basketball), birds in flight, landscapes, panos, portrait work, etc., and it did a reasonably good job at all of them.
I didn't say the AF system was a serious limitation. Why would you interpreted my comment as referring to the AF system?

I can only think of two aspects of the 6D that qualify as limitations: the AF system and the frame rate.  The frame rate might not be 1DX speed, but it is fast enough to be usable to get great shots, even for sports.

Anyway, since you brought it up sports photography, why would a professional sports photographer choose the 1D-X to shoot at the Olympics rather than the 6D?

The question is not which one is better.  There's no question that the 6D is outclassed by the 5D Mark III and the 1D X.  The question was whether it has serious limitations—that is, if there are aspects of it that would prevent someone who knew how to use it from being able to get decent shots.  Personally, I don't think so.

As for Samsung, I think you're right.  Why not go with them?  They've integrated the Android OS into some of their cameras.  You can shoot an image, run your favorite mobile processing app, and share it all in the span of a few moments right from the "camera".  Time barriers to creativity collapse.

IMO, Samsung entering the interchangeable lens camera market is a recipe for disaster.  I have very little faith in their ability to pull it off, because it is too completely different from any market in which they've ever had the slightest bit of success.

The big problem is that Samsung has a long history of building cheap consumer crap that doesn't last very long, with buggy firmware that never gets fixed.  They have no need to design for the long term, because consumers throw everything out after two or three years anyway.

Contrast this with the harsh reality of photography—that glass (good glass, anyway) is expensive.  It is a long-term investment.  It has to be done right the first time, it has to last for the long haul, and it has to be forward-compatible with future hardware for many years, or else people feel ripped off.

Samsung has not shown the ability to design for the long haul, and worse, has shown plenty of evidence that they are completely unable to do so.  Just take a look at all the horror stories from people whose Samsung refrigerators have exhibited repeated hardware failures under warranty, in which the electronic brain crashes and all of their food spoils.  And this is a company that you think will build lenses that people will still be using in twenty years?

That's not to say that they couldn't cheat—build bodies that are electrically compatible with a more competent company's lenses—but I can't see them ever being a serious player in the high-end camera market, because they have so epically failed at every attempt to build high-end products of any kind every time they've tried..

EOS Bodies / Re: EOS 6D Mark II to Move Upmarket? [CR1]
« on: October 14, 2014, 04:52:38 PM »
The 6D, while completely capable of capturing beautiful images, has some serious limitations for certain types of photography. That is not to say it is a bad camera, just better suited to other types of photography.

Sure, a better AF system would be better for sports, but I'd hardly call it seriously limited.  I've used a 6D to shoot sports (basketball), birds in flight, landscapes, panos, portrait work, etc., and it did a reasonably good job at all of them.

EOS Bodies / Re: Multilayer Sensors are Coming From Canon [CR2]
« on: October 13, 2014, 03:22:27 PM »
Quote from: dgatwood link=topic=2316channel 1932#msg4channelste=1413081039
It would also be a tremendous amount of data, and a lot more data to be factored into image processing. Five layers at 25megapixels is 125megaphotodiodes. At 14-bit, that's around 235-245 megabytes per image. RAW editors would also have to add the right kind of support to utilize those extra layers.

Even three layers would be unworkable uncompressed at 25 megapixels per layer.  It's hard enough to deal with 25–30 megabyte image files, much less four times that.  They're clearly going to have to come up with a good lossless compression algorithm.  A lossless scheme similar to PNG should get you about 2.7:1 compression, which means about 81 MB with all five layers included, or 49 MB with only three layers.  But I think it is possible to do better than 2.7:1.  After all, the high order bits of nearby pixels are likely to be fairly similar except near high-contrast edges, and the more bit depth you have, the more identical bits you'll probably have.

Storage space probably isn't nearly as big a concern, as yes, you can compress the files. However when your working on them, you need the full pixel data. It's like opening a large 16-bit or 32-bit TIFF in Photoshop...if you look at the memory usage, it is usually several hundred megs.

So what?  When you're working in Lightroom or Camera Raw you're working on demosaiced data anyway at 16 bits per channel for four channeks.  The size is 8 bytes * pixel count.

I doubt they maintain an alpha channel during processing; it would always be 1.0f/65535.

Either way, jrista is correct that when you process the data, you'll need more working space, because every time you edit the IR/UV handling, you'd have to redo the computation where you collapse the five channels into three.  (I'm not going to call it demosaicing because it isn't mosaiced in the first place.)  With that said, outside of cell phones, the difference between 50 megabytes (25 megapixels at two bytes each) and 250 megabytes is IMO mostly noise compared with all the other memory usage in these sorts of apps.

It also requires more CPU power to read three or five 16-bit values than one; effectively, each destination pixel in a traditional debayer algorithm requires reading on average one new subpixel value that hasn't been read before, so assuming your algorithm achieves maximum reuse of values (which it won't), a multilayer sensor would be 3–5 times as CPU-intensive.  In practice, it is probably closer to a factor of two, though, and I'm pretty sure the debayer algorithm is a small percentage of the total processing, so I doubt this will be a serious problem.

Basically, if your computer is barely tolerable now, it might be intolerable with a multilayer sensor.  In practice, though, the apps will probably evolve to take better advantage of multiple cores, and this will probably make the difference moot.

Speedlites, Printers, Accessories / Re: CF Cards Vs SD Cards
« on: October 13, 2014, 12:09:36 AM »
Using 1d4 and 5d3 its simple: I prefer the CF cards due to the slow SD interface
In my Sony or Fuji the SD shine with speed.....

7d2 supports finally the UHS protocol- wow. Canon, the late adopter.

The 6D supported UHS-I (2009), too.  Too bad Canon still hasn't adopted UHS-II (mid-2011).  :/

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