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Messages - CarlTN

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91
Animal Kingdom / Re: BIRD IN FLIGHT ONLY -- share your BIF photos here
« on: April 03, 2014, 04:30:32 AM »
A less good job with the 6D and 70-300L, lol.  Difficult to get these, was all the way in at 300mm (these are almost full frame images, downscaled).  Distance was about 6 feet, conditions relatively dark...single shot AF mode.  Shot through double pane window glass, at a 45 degree angle!  I doubt servo would have helped...might have on a 5D3 or 1DX.  This is the delay of my reaction time combined with the camera's shutter lag.  Both of these were just single snaps, not a series.  The birds are definitely out of the frame by the next in a sequence at 4.5 fps anyway!  At least the back feathers on the chickadee and the tail of the titmouse are close to in focus.  ISO 10,000 for chickadee and 6400 for titmouse, shutter speed 1/1000, both shot as jpegs only.

92
Animal Kingdom / Re: BIRD IN FLIGHT ONLY -- share your BIF photos here
« on: April 03, 2014, 04:22:48 AM »
Mollymawk (medium sized Albatross) Tasman Sea, NZ

6D 70/300L combo











Great job with the 6D!

93
Photography Technique / Re: 1D X - 12 FPS or 14 FPS?
« on: April 02, 2014, 10:53:54 PM »
Why wouldn't an array of strobes work?  One could hand off to another, that way you could either have more flash power and fast recycling time, or even more flash pops per second.  Of course the light source/direction from each strobe would alternate between each photo frame, but that might give more interesting lighting to choose from in post...besides the added wing positions.

94
EOS Bodies / Re: Canon's Medium Format
« on: April 02, 2014, 10:41:43 PM »
So arguing that the DP2, which itself is still just a 4.7mp camera (or even the SD1, which is a much higher resolution Foveon), is potentially equivalent to a 39mp camera, is gravely missing the point of having a truly higher resolution sensor (in luminance terms...luminace is where detail comes from, color CAN be of much lower spatial resolution so long as your luminance information is high...as a matter of fact, this is actually a standard practice in astrophotography, to image at high resolution in luminance, then when you switch to RGB filters, you bin 2x2 or 3x3, which increases your sensitivity, and reduces your resolution by 4x or 9x...and your never the wiser when looking at the final blended result). It buys into the very misleading hype that Sigma spews, which I believe is ultimately, in the long term, going to damage their reputation and hurt Foveon (because as more people try to produce images with a 4.7mp or 15mp Foveon sensor that compare to even the regular old D800, let alone the D800E or the 645D, and realize they simply cannot...they are either going to ditch Foveon and go back to bayer type sensors, or they are going to begin badmouthing Foveon.)


Nobody said the first generation Foveon sensor is equal to 39 MP.  Jrista, again you learn about what you're interested in, but this leaves a lot of facts for you to miss. 

When I mentioned the "new DP2", I was referring to this...it's called the Quattro.

http://www.sigma-global.com/en/cameras/dp-series/

...And it's most definitely more resolution than the SD-1...it's a new sensor with more pixels.  Just exactly how many pixels it is, is kind of unclear.  I think Sigma don't mind that it is unclear...lol.  The actual pixel dimensions of the RAW image, might be 19 MP, or might be more.  For some reason it can produce JPEGs that are 7680 x 5120 = 38.3 MP. 

To argue about what outresolves what, on such a new product, is a waste of time in any case.

I try to speak about what I have had experience with.  I've owned the original DP2, and it most certainly had more resolution than its native 4.6 MP image.  As I said, it could easily scale to about 25 MP, and still look sharp enough to me for a print at 300 ppi. 

So there's no reason to start bashing Sigma, and talking about what "TROUNCES" what.  Nobody thinks a crop sensor is ever going to be "better" than a full frame sensor...other than you and your 7D :P.  Everybody knows nothing compares to the mighty 7D!


I don't know where you guys are getting your info. On your own site, the DP2 is listed as having 29mp effective (non-masked) "photo detectors", which are the same thing as a photodiode. From the dp-series link:

Color Photo Detectors    Total Pixels: Approx.33MP, Effective Pixels: Approx.29MP

That is 29 million PHOTODIODES. That means, from a SPATIAL standpoint (actual resolving power), you have 29/3 million PIXELS (actual square areas on the sensor that are light sensitive), or 9.7mp. The DP2 that you are referring to is a TEN MEGAPIXEL sensor. Not only that, it is a 10mp APS-C sized sensor, so were talking pretty small pixels.

I'm sorry, but it doesn't matter how good those pixels are...there is no way, physically, that they could ever compare to the 36.3mp of a D800 nor the 40mp of the 645D. Spatially, from a luminance (detail) perspective, there is no loss of data or resolution in a bayer array. There is only, ONLY, a loss of color data or color spatial resolution. The loss of spatial color detail is a bit of a detractor for bayer type sensors, it hurts their color fidelity a little bit, however it is not enough of a detractor to warrant calling a 9.7mp Foveon as good as a 39mp bayer. The FULL detail luminance from a bayer is more than enough to offset the loss in color detail.

Neuro has explained how a properly designed OLPF (which is usually the case these days, even leaning towards the slightly weak side more often than not), despite blurring high frequency data, is not a huge detractor for bayer sensors as OLPF's blur predictably and consistently across the area of the sensor, meaning a light sharpening filter in post usually reverses the softening impact of an OLPF.

The whole "eqivalent megapixels" deal that Sigma uses is also very misleading. Currently, today, megapixel counts are based on output image widthxheight. A 15mp Sigma Foveon is 15mp, in terms of actual megapixels stored in the output JPED image or a JPEG that you can create from RAW. It may have 45 million photodiodes, but that is not the same as megapixels, and I really wish Sigma would stop being so misleading.


No more misleading than stating a sensor has so many megapixels, when each photodiode samples one color, and the other two are interpolated in the JPEG.


Your misunderstanding. Every bayer pixel may have only one color, but regardless of color, every pixel receives "light". This is why the spatial resolution of a bayer sensor is so high, and why a D800 is capable of resolving so much detail. If you convert a bayer sensor's data to monochrome, you effectively have just the full detail luminance. Advanced demosaicing algorithms like AHDD are explicitly designed to preserve as much luminance detail as possible, while effectively distributing color data to avoid mazing artifacts and other demosiacing quirks. A bayer sensor needs no interpolation from a luminance standpoint, they only need interpolation from a color standpoint. Bayer sensors have nearly their full resolution in terms of luminance, and since luminance is really what carries your fine detail, they DO have FAR more resolution than any Foveon on the market today, including the SD1.

This isn't missleading, it's how the physics and mathematics of interpolation work. Interpolation algorithms like AHDD are actually capable of producing crisper, smoother, sharper results with a bayer than your standard, basic demosaicing algorithm, and AHDD is pretty ubiquitous these days (LR/ACR use it, Adobe Aperture uses it, and it's a demosaicing option in most Linux RAW editors like RawThearapy and Darktable.) AHDD is even used in lower level tools, often used for astrophotography, like DeepSpaceStacker, Iris, and PixInsight.

The only loss with a bayer type sensor is in terms of color spatial resolution and color fidelity. The most obvious of those is really color fidelity, as when chrominance is blended with luminance, our eyes can't really tell the difference, or at least the difference is small enough that it isn't an issue unless you are directly comparing, side-by-side, a Foveon and Bayer image with the same image dimensions (in other words, if you had a 10mp bayer and a 10mp Foveon, then you would be able to tell that the Foveon had slightly better color microcontrast and better color fidelity...however when comparing a 35 or 40mp bayer to a 10mp Foveon, the only visible difference MIGHT be sharpness...that would depend on the strength or presence of an AA filter.)


It's not "my own" website.  If you calculate the RAW image dimensions, it is 5424 x 3616 = 19.61 MP.  Obviously there is some processing and/or interpolation involved to arrive at this image size, but there it is.

I never claimed it would outresolve a D800 "spatially", I just asked if he had seen it, and that it looked interesting...especially considering it's a crop sensor.  The fair comparison would be, what is the resolving power of this camera, compared to the 70D and the Exmor 24 MP 1.5x crop sensor's best output, with its best lens mounted.  To compare it to a full frame, is not a fair comparison, for various obvious reasons.

You're claiming that this new Sigma camera and sensor, could not resolve more than 10 MP worth of (equivalent "bayer"?) spatial information.  I submit that you are jumping to conclusions, and they are quite possibly in error.  Let's wait and see how it does when tested, rather than approaching a new product with a closed mind, and conclusions drawn...because of an unapologetic bias against the design, and the manufacturer.

It's not as if Canon have not explored their own foveon-type sensor ideas, all mockery aside.

95
EOS Bodies / Re: Canon's Medium Format
« on: April 02, 2014, 10:28:16 PM »
My girlfriend bought 5Dc couple of years ago and I bought 5Dmk3 couple of months ago. We print mostly on fuji machines on fuji luster paper. We have bunch of Lenses. Shitloads of MF& 135 cameras too. 2 MF/Lf scanners and one dedicated 35mm scanner. Both of us make our living from photography and live photography everyday. On assignments both of us shoot nikons, canons. We love every camera which shuffles in our hands, be it fuji, sony, olympus or canikon.
In our bedroom we never discuss the issues posted on previous page of this thread. In our kitchen we never discuss the very same issues. When we have drinks with our colleagues we never discuss these same issues.
What have this world come to?

Haven't seen much girls around this forum.

True, there aren't many "girls" on this forum.  But what does that have to do with anything?  And I'm not surprised you wouldn't discuss the science behind the hardware of the cameras you use every day.  It's because you aren't curious about it, it doesn't fascinate you.  Or at least not both of you.

96
Lenses / Re: Canon 400mm DO
« on: April 02, 2014, 10:18:15 PM »
Carl
What do you think of the 400 DO outresolving a 600 f/4 L?
Alan
I have been searching for the images I took to illustrate my post but I have to admit I can't find them - sorry! They may be on my old PC (which I still have) so I will see if they are on there.
Basically I fancied one (but couldn't afford it!) so I tried out the 2 at my local camera shop. As a comparison I then mounted my Canon 600 F4L IS and took pictures of the same subject (a BMW 3 Series) from the same place. The difference was that we could see that the lacquer on the rear of the car had crazed slightly with the DO lenses we weren't easily able to pick this up with the 600.
As I said I will have another look for the images.
The 400 DO is certainly a very controversial lens - but the ones I have tried have impressed me though less so with extenders.

Yes, I think the use case for the 400 DO is the bare lens.  If you plan on only using it with extenders, you won't be getting the most out of it.  That's true with all lenses, but especially with one that is not quite up to the "series 2" sharpness.  Even though I've yet to try one, I do feel the 400 DO is not deserving of the bad reputation...however I think I read somewhere that the earlier samples from a decade ago or so, may have had some production inconsistencies.  That alone could have contributed to a lot of the negative buzz on this lens, and has endured.  It was first introduced in 2000.  So most guys who are ready to blow a lot of cash on a supertele, want "the latest and greatest"...and anything that isn't, is sub-par to them.  It's a similar snobbishness that third party lenses usually get.  But I was surprised at how poor the Sigma 120-300 f/2.8 looks in Bryan's tests, even compared to the "less than perfect" 400 DO.  Yet the images I've seen from it online, look pretty sharp with decent contrast.  I guess it just means the better lenses would be that much better doing the same shot.

97
EOS Bodies / Re: Patent: EF 85mm f/1.2L III and Others
« on: April 02, 2014, 10:06:58 PM »
Quote
[...]this lens has really bad LOCA that's difficult to fix in post[...]

Did you try DXO Optics? I have no problem with LOCA/CA after developing it in this Raw-tool. Sometimes, if they're really harsh I also use RawTherapy for manually optimze some pictures... but normally all optical problems are gone after a stock conversion. And..no, this is no advert. But in the beginning I also thought the OOC-JPG is the final picture... but hell, there is so much more to get of your pictures. Especially with the 85LII.

I'm surprised how good LR is with LOCA/CA...

98
EOS Bodies / Re: Patent: EF 85mm f/1.2L III and Others
« on: April 02, 2014, 10:05:49 PM »
Apologies guys, getting my loca and coma confused....but it's not something which is much of an issue with portraiture, I've never pointed this lens at the stary night sky. With all large aperture prime lenses, one has to take the vices with it's benefits. It's not a perfect general lens but it takes some fine portraits.
I have used it for landscape work, which showed that my copy is very sharp wide open and stopped down. But it's heavy for an 85mm prime and it's max stopped down aperture of f16 is a bit short for star bursts

Not many users of this lens are that fussed by weather sealing. Adding a rubber ring doesn't really add much to it's weather sealing capacity. I've ridden my 85IIL in quite heavy rain and not had any issues:
https://www.flickr.com/photos/23849425@N06/4494339793/in/photostream/

Well they sure are bothered by the Sigma 35 Art not having a rubber ring...I guess if it cost $2000, then they wouldn't have a problem?  lol.

99
...the processor that controls autofocus, very likely uses a lot less power than the 1DX's autofocus processor (it's a "Digic 4")

The Digic4 chip in the 1D X processes only data from the 100,000-pixel RGB metering sensor. The Digic4 chip is not the AF processor, although it does feed data to the AF processor to support 'intelligent tracking and recognition' (iTR, which uses size/shape/color for AI Servo tracking).

Interesting.  In any case, it seems to me the 1DX requires more processing power than the D4 or D4s.  It's possible that just running that extra Digic4 processor uses up a lot of power.  Unless you think the power is being sucked up elsewhere...by the shutter and reflex mirror motors or something.  The LCD screen surely does not use any more power than the one Nikon uses...they might even be the same screen, I forget.

100
See the idiotic comment at the end. I sent in a comment 2 days ago but it is awaiting moderation............

http://blog.iamnikon.com/en_GB/product-news/nikon-d4s-review-experts-verdict-bob-martin/


I agree, the guy is very biased.  Never mentions how it compares to the 1DX, or even mentions the 1DX.  Could that be because he's never used one?  I can only guess that he has not.  Obviously he's a committed Nikon and Ashton Kutcher lover.

Have any of you...anyone on Canon Rumors' forum...seen an unbiased test of the D4s, or better yet, a comparison of it and the 1DX?

I suspect there are things it might do better than the 1DX, but I doubt it can autofocus better...and it certainly still can't shoot as many fps.  Seems like the only definite thing it can do better, is last longer on a battery.  And why is that?  Does it not use the same 18650 tri-cell pack?  If so...it seems to me that a camera would last longer, if its digital processing used less energy.  And that could at least partly be because, it has less processing power...It needs less for one basic reason.  It has 16 MP vs. 18 MP...but also, the processor that controls autofocus, very likely uses a lot less power than the 1DX's autofocus processor (it's a "Digic 4").

I suspect that the 1DX replacement, probably still won't last as long on a charge, as the D4s, even if it has more efficient processing and better batteries...because Canon will still opt for the maximum processing they can cram in there!


Efficiency does not necessarily have to compromise processing power. If you notice, successive generations of Intel processors have gotten more powerful AND more energy-efficient.


Kind of an apples and oranges comparison there, though.  Canon aren't manufacturing the processors, are they? 

101
Sports / Re: Your favourite motorsports events
« on: April 02, 2014, 09:57:42 PM »
Hallo,

Keep Smiling!


About 9.000 HP !


Sorry - no winner!



Looks bigger than Top Fuel engines!

102
Software & Accessories / Re: Tripod & Head - $500 or less
« on: April 02, 2014, 09:55:42 PM »
If you are going to buy a tripod buy the last tripod you will ever need.  Same for the head.  DP review recently did reviews of 10 full size ball heads.  most are out of your range but one budget model was found that is very, very good.  http://www.dpreview.com/articles/8192473209/battle-of-the-titans-top-ball-heads-tested/7Start with this $200 head and spend 300 on legs.  Carbon fiber has advantages but you will get much more bang for your buck with Aluminium.  I liked Benro and Manfrotto.  you should do very well at $300 dollars.  2 points to consider.  3 section or 4 section. 3 is quicker to setup and use, 4 will be smaller when carrying.  The other thing to consider is leg locks.  Some people like the twist ones, I like snap hinge ones.  your taste may differ.  I like the hinge because I can see when it's locked.  That prevents surprises if the twist is not locked.


Interesting.  They didn't give a reason for not including the Giottos in their test.  Did they intentionally exclude Chinese brands?

103
EOS Bodies / Re: Will the next xD cameras do 4k?
« on: April 02, 2014, 09:53:35 PM »
Regarding Don's problem with a beat frequency in bird wings, if you have software capable of doing it, you could probably record at 60fps, then interpolate that sequence back down to 24fps for inclusion with other 24fps sequences, WITHOUT resulting in the 60fps sequences playing back as "slow motion".


That's EXACTLY what I did....

Still playing and learning.... and having lots of fun doing it.

BTW... GooseCreek2 on Vimeo is what happens when you shoot geese at 30HZ....


Have you tried shooting at 24fps instead of 30fps? Just curious if that would help. BTW, unless you've configured things differently, if you are shooting at 30fps, I would expect the actual shutter speed to default to 1/60th of a second. Given that, it isn't all that surprising that your getting some stutter...it's that whole timing issue (which will present regardless of whether you are playing back at 60Hz, or down interpolating your video to 30fps for playback at 30Hz). If you drop to 24fps, your shutter speed would be 1/48th of a second (by default, at least I would expect), and that offset might help avoid the stutter problem when playing back.

I'd also offer that NOT harrassing the geese while in your canoo would probably avoid wing beats entirely. ;P

Also, what do you use to process your videos? Premier?


The 60D allows a shutter speed of 1/30 second when shooting 30FPS. Obviously, they cheat and it isn't really 1/30th but is close to it...

The editing software I have for video is Pinacle Studio. I do NOT recommend it.


Oh yes, I've encountered Pinacle Studio. Bleh.

I am a bit surprised that at a shutter speed of 1/30th, your getting stutter like that. Maybe it's still just a timing issue,  but I would have expected 1/30th to produce a bit more motion blur, which should smooth out the issue a bit. Of course, these are lower end DSLRs...they aren't exactly designed for video, it's more of an afterthought, and they all still have rolling shutters and the like as well. (Even the GoPro's have rolling shutter issues...a friend of mine builds and flys model airplanes, and he often sticks his gopro on the plane itself for some cool videos...but wow, the rolling shutter and stutter effects are BAAAD.)


The GoPro footage I see on tv via helmet cams in Supercross racing, does not appear to have any rolling shutter issues, but maybe it is subtle...I don't know.  I thought the whole appeal of GoPro was that it didn't have rolling shutter issues, at least not when compared to similarly priced consumer level video cameras.

104
Sporgon, I think the small canopy on the 109 is intentional, to make the pilot harder to hit.  The plane was really not a great design, relied too heavily on the huge canon that fired slowly and didn't work a lot of the time.  As I commented in an earlier thread...it's very ironic that the 109's the Spanish airforce used in the 1950's, use the Merlin engine from the Spitfire and P-51!

105
Hallo,

the Messerschmitt Me 262 is a replica with General Electric J85/CJ-610 Jet Engines, not the original Juno.
http://en.wikipedia.org/wiki/Messerschmitt_Me_262
http://www.lexikon-der-wehrmacht.de/Waffen/Me262.htm
http://www.flugmuseum-messerschmitt.de/

gazzo


The airframe is a replica too?  Or is it an original airframe with different engines?

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