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Messages - LetTheRightLensIn

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2746
Lenses / Re: Wide or ultra-wide angle with excellent corner performance
« on: September 28, 2012, 09:04:03 PM »
Good evening to all,

Knowing that there's no perfect lens, I am desperate to find an ultra-wide angle or wide angle with a performance excellent or very good in the corners.

Here's what I found with the lenses I had or still have:

(had) 17-40mm L f4.0: Poor in the corners at 24mm and 20mm, but unusable for me becaus it's only f4.0.

(had) 16-35mm L f2.8 mark ii: Very poor in the corners at 24mm and 20mm, at 16mm it was terrible. 

(have) 20-35mm L f2.8: Much better than all the previous ones in the corners and at any focal length, but with two probems: the minimum focusing distance is too long, only 50cm; and the lens is very prone to flare.

(had) 24-70mm f2.8: I always found this lens not very sharp at 2.8, and the performance in the corners was not better than 17-40.

Are the 20mm f2.8 or the 24mm f1.4 better? The lens I want doesn't exist? =) I will mostly use it at 24mm or 20mm.

absolutely forget the 20mm
or the 24 2.8 non-IS

You need modern primes or a superduper zoom.

Basically you tried almost everyone but the ones you need to try  ;D.

24 1.4 II is very good at the extreme edges, extreme corners are not perfect but ok enough (not at f/1.4 though! gotta stop down some)

24 T&S II has good corners

zeiss is pretty decent

24 2.8 IS is apparently sharp there stopped down

17 T&S might not be bad

samayng 14mm is actually pretty sharp stopped down there is seems, VERY wide and good deal of distortion though

the samples from the new 24-70 II look decent, stopped down a bit, other than maybe the extreme corners (but extreme edges appear to be very sharp stopped down a bit it would seem)


2747
EOS Bodies / Re: Comparing 6D with 5D3
« on: September 28, 2012, 05:10:56 PM »
The 6D sensor is just 35.8mm x 23.9mm.
The 5D III's is 36mm x 24mm.
I don't know how significant that difference would be to you (or me.)

6D 855.62 sqmm
5D3 864 sqmm

6D has a crop factor of 1.01 compared to the 5D3.

So the 6D is definitely going to be the better cam when you are reach limited.

 ;D

2748
EOS Bodies / Re: Comparing 6D with 5D3
« on: September 28, 2012, 05:08:26 PM »
Am I reading it wrong? The 6D performs better in half the light of MKIII is able to do??? What does that mean exactly? Focusing in low light?  :o

Yes, AF (with the center point and an f/2.8 or faster lens) is possible in half as much light with the 6D as with the 5DIII/1D X.  In theory, based on specs - whether that holds true in practice remains to be seen.

That makes a huge difference. I don't shoot sports but lots of candid in-motion people. I'm just use to using center point focus on everything I do in low light situations. Now I wonder if I really need all the extra AF points for from the MKIII if the 6D center point is actually that much better and what I'm use to. I never had good enough AF on any of my previous cameras so I just learned to only use center.

Hard to say, also just because it can focus in lower light doesn't mean that it will focus as precisely or quickly when there is enough light for either camera to handle. Maybe under bright light it will even get a bit blinded. Who knows. Nothing below 5D2/7D has been much reliable for one shot AF from Canon and even those two, especially the 7D, miss often enough. The pro 1 series and especially new 5D3/1DX are better.

2749
EOS Bodies / Re: Comparing 6D with 5D3
« on: September 28, 2012, 05:05:38 PM »
One thing no one has mentioned so far, but might be relevant for some users.  The 5DIII does not have a user-replaceable focus screen, but the 6D does - and it's compatible with the Eg-S super precision screen (whereas even the 1D X is not metering compatible with the corresponding Ec-S).

This is not true. Adapted screens can be fitted to the 5D Mark III by simply removing two small screws. There are a limited number of suppliers for the screens that, while not as easy to replace as in the 1Dx, or in fact the consumer APS-C devices, take no more than ten minutes to swap.

Yeah but the metering gets messed up then and there is no menu item to compensate.

2750
EOS Bodies / Re: Comparing 6D with 5D3
« on: September 28, 2012, 05:04:12 PM »
Don't forget ergonomics and button layout.   Myself coming from a 7D, it would be awkward going to the smaller joystick less 6D.   Personally I like the larger body, even the 60D feels a bit small. 

Personally I think the joystick is a con.  The setup on the 6D is just like the 60D and I loved it.  Once I went to my 7D, I was disappointed.  You have to constantly switch back and forth between the pad and joystick.

The wheel sounds like it would be very awkward to quickly change focus points around precisely.

2751
EOS Bodies / Re: More Big Megapixel Talk [CR1]
« on: September 28, 2012, 04:58:34 PM »

Well, I don't think its that simple. Which Canon books? They have a presence in countries all over the world. And which R&D budget? They've done research and development in multiple countries. Are they moving R&D out of China and into Japan? Are they moving more to the US? Or out of both the US and China? Or more into China? Following a multinational companies books isn't an easy thing to do. Who knows exactly what Canon is doing? Anyone who claims to know what they are going to do in the future is just speculating.

Hopefully you are correct. One was some Swedish website or group and I don't know whether they knew how or were able to dig deep enough or not. They said they didn't see evidence of building any expensive new sensor lines. But who knows.

The R&D slash was Canon person but not from DSLR group (although I believe referring to that group). But who knows.

Hopefully they are wrong or it won't matter.


Quote
I'm rather skeptical about "some website" looking over Canon's books. As I said, not an easy task to figure out what a multinational company does with its money, what its funding, etc. It takes armies of accountants to manage that stuff.

Hopefully and possibly so.

Quote
If Canon really does slash their R&D budget and refuses to improve their fabs, that very well may hurt them in the long run. But its illogical to think, and for Canon to actually ignore, the threat of competition. I don't believe they intend to simply ignore Sony.

Hope so.

Quote
To be honest, when you have a significant advantage...whatever that advantage is, even if its simply market share and momentum...its the nature of the free market to capitalize on that advantage as cheaply as possible. Can't say I particularly like that, I really want a nice high-res, low noise landscape camera...but its the nature of the beast.

True, although such companies usually stumble more in the long run than the ones that keep charging, but it is a very common occurrence for companies to end up acting like that. For some you can sort of understand the fear about pushing forward and risking this and that for cameras it seems a lot more stable so it seems a bit less understandable but it had definitely happens all the same.


2752
Lenses / Re: what filter for my first "L" Lens
« on: September 28, 2012, 04:47:50 PM »
Cheers well iv just purchased a B+W 77mm UV MRC

is this good yeah?

yeah that's good  ;D

If conditions are safe and you are shooting lots of back lit stuff you might want to take them off, especially on wide angles as even the best filters, add more reflective layers and it's a flat bit of glass in front, although it still might not be too bad most of the time.

2753
Lenses / Re: what filter for my first "L" Lens
« on: September 28, 2012, 04:46:17 PM »
Good evening all,

i will say hi as I'm not new just this is my first post.

wondering what filters people use to protect there lenses if any...

I'm really undecided on what type of filter i need i have just purchased the 17-40 L so i know i need a 77mm filter and i know i need a top quality one as there would be no point putting cheap glass in front of it..

so what do you guys and girls do?


any help appreciated.

thanks

I like B+W, good quality and easy to clean. I think they might have ones that are different now, but a few years ago for sure, Hoya were a nightmare to clean, some sort of weird surface, if you go Hoya I'd verify that their new ones are easier to clean and make sure to get that particular newer model.

You don't need UV, clear is fine, clear sometimes costs more though anyway.

A circular polarizer can be very nice to have.

Make sure to get all of them with the MRC coating.

2754
EOS Bodies / Re: More Big Megapixel Talk [CR1]
« on: September 28, 2012, 02:25:58 PM »

Your missing my point. IF <-- key word here -- Canon can reduce their ISO 100 read noise to the minimums recently seen in their cameras (1.5e- worth in the 1D IV sensor), they then could achieve an improvement in total DR at ISO 100. Sony Exmor effectively normalized read noise across all ISO settings. DXO's measurements seem a little sloppy...I've seen measurements from other reviewers that have much more consistent results, so my guess is that the D800 has a consistent 2.7e- read noise at all ISO settings (effectively the minimum read noise at all ISO settings.) IF Canon CAN DO THE SAME THING....make their minimum read noise from the highest ISO the read noise for all ISO's, like Sony did with Exmor, then Canon would have lower read noise than a D800.


Yeah but they have not been able to since they have bad read noise at one of the two stages, at higher ISO they boost the shadow signal above the point where the one stage adds tons of garbage to the lowest end of the signal. I mean that's the whole trick isn't it? You could say the same about just about any of the sensors out there.

As someone said if you use ISO1600 to read shadows and ISO100 to read highlights you'd have good DR.

Nikon can do it now because of the Exmor ADC architecture. They hadn't been able to do it too much before Exmore, although their D4 does show that you can do better than Canon does even with a pure straight design if you have better fab process or something.

Quote
As for your presumption that Canon is incapable of developing a new fab or producing complex sensors at 180nm, there is nothing to stop Canon from innovating.

The unfortunate thing is that some website claims they looked over Canon's books and see no sign of the sort of expenditure that hints that they have done this and one Canon employee says they just slashed R&D development.

Quote
Thats what competition does in a free market...it spurs innovation. Right now all we have about Canon's next cameras is rumor and speculation, but usually those rumors contain nuggets of factual, if not 100% accurate, insight. Based on the current rumors, I speculate that Canon IS innovating, and developing ways to improve their sensor technology beyond the current limitations it experiences today.

I sure hope so. I'd almost think they'd have to be. But then again I was sure the 5D3 would show low ISO improvements too and again some websites say looking over the books they don't necessarily see positive signs, at least not in terms of new fab lines, but I have no idea how well the website really looked things over or if Canon has some other way. But you would think they'd have to wake up to it all at some point.


2755
EOS Bodies / Re: Who said Canon cameras suck?!?
« on: September 28, 2012, 12:50:14 PM »
I don't necessarily disagree, however I think your starting to conflate contexts. I was trying to discuss DR in terms of a digitized image in the context of scaling, which I think narrows the scope and does simplify things a bit. Your now talking about DR in a much larger context, that of the sensor. That moves us out of the realm of the digital and into the realm of the analog, and I fully agree: Dynamic range in the analog realm of a sensor is an entirely different beast, and a much more complex discussion. But...we were originally talking about the dynamic range gained by the act of downscaling a high resolution image. In that context, I don't believe we can "interchange" the dynamic range gained by normalizing read noise...which always exists in the lower levels of a digital image...with highlights. You would always be gaining on the shadow end when you normalize and average read noise, however I think we've both demonstrated that gain is small, even though it can be called a "full stops worth".

A stop of dynamic range in the shadows is interchangeable with a stop of dynamic range in the highlights because you can always meter differently (e.g. underexpose by a stop)

You went off on a bit of a tangent suggesting that the extra dynamic range does substantially not increase the number of "levels" of luminance available, and I showed that it actually does (more precisely, that if I reduce noise by a factor of two, I get twice as many luminance levels). I also showed that by downsampling you can interchange spatial resolution for both dynamic range and number of luminance levels.

So the analysis where you try to demonstrate that the difference is "small" by using that table is incorrect. It's incorrect because when you add noise, you don't just lose the "bottom stop(s)" on the table (for example, levels 1-15) and keep all the others, you're really losing information content in the low order bit(s). You're not eating away at the "bottom of the table", you're eating away at the low order bits.

Perhaps we are on different pages. Once an image is digitized, its digitized. It has a fixed bit depth. In the case of modern DSLR's, the 14-bit output of a RAW is fixed, and the physical dimensions of that image are also fixed (so downscaling really isn't an option to start with...not if you wish to continue working with the image as a RAW image.) If you do export that 14-bit raw to say, TIFF, then you now have a 16-bit image. The number of bits is fixed. It doesn't change. If you scale that TIFF image down, yes, you can mitigate noise. You'll really be mitigating two types: Photon Shot and Read Noise. When it comes to Photon Shot, the D800 doesn't have any real advantage over any other camera, and the benefit of scaling would be the same for any image. When it comes to Read Noise, that noise only exists in the black and shadow levels. If you scale an image down, your only affecting the bottom small percentage of the total tonal range of your TIFF image. You could certainly move the gray point around, but your not redistributing bits...your only redistributing the existing tonal levels in the image...so the gain in the shadows of a few levels isn't going to translate into thousands of highlight levels by moving the gray point around after downscaling.

Again, though, I've been trying to discuss this topic in the context of a digital image on a computer. You keep conflating the issue by bringing in the behavior of the hardware in a camera. I'm not talking about metering and adjusting the exposure value pre-exposure time. I'm talking about working an image in post after its been digitized by the ADC and imported off the camera/memory card, as the original debate was whether you can really actually gain over a stop of DR by the simple act of scaling an image down (an act that occurs well beyond the camera, so discussing how you can use the DR of the hardware to gain shadow or highlight range is out of context.) I believe you can gain a couple stops of DR by downscaling, however since it is in the "lower order bits", or in the darkest tonal levels of an image, the gain is minimal. Were not talking about a huge difference overall, we are talking about a very small difference overall. That difference well indeed may improve the dynamic range of your shadow detail a bit, but its not like your gaining more than double the total tonal range you had before (which I had mistakenly thought was the opposing argument.)

Quote
I'm still adamant that the D800 sensor is only capable of what its capable of...which by all indications, including DXO's, is about 13.2 stops.

Yes, that's 13.2 stops per pixel. I'm not sure why this matters so much -- the Canon also drops (by about .8 EV) when you go from print to screen because the two cameras don't differ that much in megapixel count. Depending on whether you use DxO's "screen" or "print" number, the Nikon leads by 2.2Ev or 2.5Ev. I'm not sure why you think those 0.3 Ev matter a whole lot -- either way, the Nikon sensor trounces the Canon, so why devote so much effort to trying to prove that the Nikon is "only" 2.2Ev better ?

Back to your #95, the D800 user could underexpose by 1.2 stops. If he downsamples to 8mpx, he will be able to recover those shadows, and get 14.4 stops of dynamic range. I agree that he can't get 14.4 stops per pixel at full resolution.

 As long as the destination for the image is some fixed size (print or on screen) and not a 100% crop, the "print" benchmark is the one you should care about. So I don't agree for example with the notion that medium format, full frame and crop cameras are equal in terms of dynamic range even if they are on a per pixel basis.

That last statement is your mistake, though. It's also the same mistake DXO makes: Why is the assumption that a "print" is always less than native resolution (the same as a 100% crop)? The D800 has a native print size of around 17x22 (roughly speaking). If I print at native size, I am not downscaling. That effectively is a 100% crop. There isn't any averaging of any pixels going on when I print at native size, and once ink is laid down on paper, at best (assuming I use something like Epson UltraChrome or Canon Lucia ink on a high luster paper) I might get a dMax of 2-2.3, which is around 6 to 7 stops. The only time DXO's "Print DR" actually results in greater dynamic range is when that 8x12" printable image is viewed on a computer, and even then...you would require a 14-bit display to actually observe the all the detail at any level offered by a 14 stop image. Generally speaking, if I buy a camera like the D800, I'm not going to print at just 17x22. I'm going to print huge: 24x36, 30x40, 40x60. Those prints will probably be on Canvas (maybe 6 stops), or possibly on a fine art paper (which have a limited dynamic range around 5 stops.)

I argue about this because the entire notion of "Print DR" is assumptive, misleading, and attempts to nail down a specific result in a world (the world of print) that has thousands of potential final output options, viewing distances, inks, color gamuts, lighting scenarios, etc. etc. Its a terrible concept, a very misleading concept. It doesn't belong in the world of objective camera testing, at least not the way DXO does it where its a primary factor of measure for Sensor IQ.

He is not conflating anything. You have a lot of knowledge but you are not getting the true conceptual meaning of one or two pretty important things it seems.

2756
EOS Bodies / Re: Who said Canon cameras suck?!?
« on: September 28, 2012, 12:46:29 PM »
I don't necessarily disagree, however I think your starting to conflate contexts. I was trying to discuss DR in terms of a digitized image in the context of scaling, which I think narrows the scope and does simplify things a bit. Your now talking about DR in a much larger context, that of the sensor. That moves us out of the realm of the digital and into the realm of the analog, and I fully agree: Dynamic range in the analog realm of a sensor is an entirely different beast, and a much more complex discussion. But...we were originally talking about the dynamic range gained by the act of downscaling a high resolution image. In that context, I don't believe we can "interchange" the dynamic range gained by normalizing read noise...which always exists in the lower levels of a digital image...with highlights. You would always be gaining on the shadow end when you normalize and average read noise, however I think we've both demonstrated that gain is small, even though it can be called a "full stops worth".

A stop of dynamic range in the shadows is interchangeable with a stop of dynamic range in the highlights because you can always meter differently (e.g. underexpose by a stop)

You went off on a bit of a tangent suggesting that the extra dynamic range does substantially not increase the number of "levels" of luminance available, and I showed that it actually does (more precisely, that if I reduce noise by a factor of two, I get twice as many luminance levels). I also showed that by downsampling you can interchange spatial resolution for both dynamic range and number of luminance levels.

So the analysis where you try to demonstrate that the difference is "small" by using that table is incorrect. It's incorrect because when you add noise, you don't just lose the "bottom stop(s)" on the table (for example, levels 1-15) and keep all the others, you're really losing information content in the low order bit(s). You're not eating away at the "bottom of the table", you're eating away at the low order bits.

Quote
I'm still adamant that the D800 sensor is only capable of what its capable of...which by all indications, including DXO's, is about 13.2 stops.

Yes, that's 13.2 stops per pixel. I'm not sure why this matters so much -- the Canon also drops (by about .8 EV) when you go from print to screen because the two cameras don't differ that much in megapixel count. Depending on whether you use DxO's "screen" or "print" number, the Nikon leads by 2.2Ev or 2.5Ev. I'm not sure why you think those 0.3 Ev matter a whole lot -- either way, the Nikon sensor trounces the Canon, so why devote so much effort to trying to prove that the Nikon is "only" 2.2Ev better ?

Back to your #95, the D800 user could underexpose by 1.2 stops. If he downsamples to 8mpx, he will be able to recover those shadows, and get 14.4 stops of dynamic range. I agree that he can't get 14.4 stops per pixel at full resolution.

 As long as the destination for the image is some fixed size (print or on screen) and not a 100% crop, the "print" benchmark is the one you should care about. So I don't agree for example with the notion that medium format, full frame and crop cameras are equal in terms of dynamic range even if they are on a per pixel basis.

+1

2757
EOS Bodies / Re: Who said Canon cameras suck?!?
« on: September 28, 2012, 02:51:45 AM »
Do you people actually take pictures or do you just sit around and analyze the camera and data all day long?  Reading all of this gave me a headache and I had to GO OUTSIDE and take pictures!

Hah I took like 7500 shots over the last two weeks. That said this thread does seem to have been ultimately pointless, to a certain extent, since it ended where it began.

2758
EOS Bodies - For Stills / Re: 5D3 - problem?
« on: September 28, 2012, 02:48:29 AM »
I don't understand why people are troubled with the dial button.  I mean come on, my 5-year old niece is able to turn the mode dial with ease.

I have it on my 60D and thank goodness Canon didn't leave it out on the 5D3 (unlike the flip-out screen).  I was asked to shoot with a different camera a few times for events  (7D and T3i without a grip) and the button kept being changed the whole time when I'm using it in portrait orientation, it was annoying.  Fortunately I only shoot in manual mode and I noticed right away if the dial had been changed otherwise I would have a lot of bad photos.

I think it's one of those little additions on my 5D3 that makes it close to perfect.  All it needs now is the reticulating screen.

agreed. Originally I was against it since it makes it a pain for a quick real time swap between C modes shooting action (making up for  still faulty AutoISO implementation) but then I was shooting two bodies all weekend with the 7D dangling around my back and hitting my backpack and I kept grabbing it and it would in weird modes and at first I'd be what the what is going on, so I quickly learned to love the idea of the mode dial button concept.

2759
EOS Bodies / Re: Who said Canon cameras suck?!?
« on: September 27, 2012, 10:26:06 PM »
Canon cameras don't suck nearly as bad as this thread does.

I agree with that!  ;D

2760
EOS Bodies / Re: Who said Canon cameras suck?!?
« on: September 27, 2012, 10:25:17 PM »
whatever did we do back when we had to properly expose.

If you knew how to properly expose you would realize that talk about wanting more DR is not primarily about 'proper exoposure'.

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