Messages

1

EOS Bodies - For Stills / Re: 5d2 vs 6d

« on: November 19, 2012, 06:54:51 AM »

@steliosk
Yeah and that 1 MP is so shitty for me. on iStock i can go to XXL with 21 but only to XL with 20.

You realize photoshop has a resizing tool?

BTW I don't see the 6D as a serious tool for a pro photographer, it's more like a 60D with a larger sensor. So I'd really go with the 5D2, it just seems to offer a lot for the money, and the AF being its only real drawback probably isn't a lot better on the 6D either. Also since the noise performance in RAW mode hasn't improved that much from 5D2 to 5D3 I wouldn't really expect a big difference between these two either. But since you're gonna have to buy new glass when switching to a FF camera anyway, it might be worth looking into another brand too (not gonna say the n-word here).

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Lenses / Re: 24-105L vs 24-70 Tamron VC

« on: October 30, 2012, 06:44:36 PM »

I like the Tammy. I own it (for Nikon), and it's a really good lens. The resolution is not on level with the primes, but it's good and has no real weaknesses. I'd definitely go for it. Combining good sharpness, really good built quality, weather sealing and image stabilization it really is a great tool for events (2.8!), traveling (weather sealed 24-70), wide angle studio/ location work in people photography, video (IS!), landscapes... In the studio I don't use it much, but it's probably the lens I use the most when I leave the house.

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EOS Bodies - For Stills / Re: 1dx, or d800e?

« on: October 13, 2012, 11:15:13 PM »

The 5D3 is probably the best wedding camera out there, thanks to its silent mode. If you do lots of weddings, keep it.
I wouldn't necessarily add a D800E. Ok, it delivers more detail of course, but I'm guessing your customers usually won't notice the difference. After all, it's 5760x3840 vs. 7360x4912 - that's 28% more per edge. It's definitely something, but is it worth 3k$ + probably at least the same in lenses?
The "new toy factor" will fade after a while and for me it fades quicker with camera bodies than with lenses, so that is really where I would put my money - or maybe flashes, dishes, sofboxes, etc.

btw I myself have a D800 and I love it, perfect camera for my needs, so I'm probably pretty much unbiased.

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EOS Bodies / Re: More Big Megapixel Talk [CR1]

« on: September 25, 2012, 09:30:51 PM »

How long until we hear about people who switched to Nikon wanting to switch back to Canon..... 

Did somebody just call my name?

No seriously, I'd say it'll take a while. For me, and I think for many other people, the Sony sensor got Nikon attention, but actually Canons recent price policy had me buy the D800 instead of the 5D3.
The 5D3, good as it is, is priced at the top end of what they could take. So is the Speedlite 600XT, the 24-70 L II (gee, look what Tamron gets you for half the price), the 1D-C and, most recently, the 6D. DPReview put it very nicely: "Whereas Nikon seems to have taken the approach of taking away as little as possible from D800 when creating the D600, Canon appears almost to have gone the other way, removing as much as it thinks it can get away with at the price."

- I'm not saying Canon is stupid to do so, and I'm definitely not a Nikon fanboy, but this is a big part of what had me switch to Nikon, and since I don't see that changing soon, my bet is that system switchers like me will not reconsider as quickly.

For the big MP body: I don't know why you wouldn't want it, all Canon has to make sure is to include various downsized RAW outputs (and yes I find it annoying that Nikon didn't have that idea for the D800). They might need a pretty fast CPU in the camera, but in principle that shouldn't be a problem. Offer RAW output @46, 23 and 11.5 MP and no one can say it has too many MP. Hardly anyone NEEDS 46MP, but having it in the bag for landscapes or some commercial shoots is definitely a selling point.

However, not only the resolution, but also the aim to go for higher DR sounds like they're back on track with their sensor development. Someone here mentioned some special technology in the Sony sensors, could you go into more detail on that? I think it is very apparent that Sony has got some magic going on for the shadow noise/ DR. It's ridiculous how those Sony sensors can save your day after you screw things up in manual mode, so Ive been wondering why Canon and Nikon sensors can't put up with that. (ok this was already answered while I was typing)

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Lens Gallery / Re: Canon EF-S 55-250mm f/4-5.6 IS

« on: April 12, 2012, 02:32:14 PM »

7D, 131mm @ f9, 1/200s

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Lens Gallery / Re: Canon EF50mm f/1.4 USM

« on: April 12, 2012, 02:29:09 PM »

7D, 1/200 @ f5.6

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Lens Gallery / Re: Canon EF50mm f/1.4 USM

« on: April 12, 2012, 02:26:58 PM »

7D, 1/200 @ f5.6

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EOS Bodies / Re: I still don't get the crop debate

« on: April 12, 2012, 01:50:55 PM »

'm not a physicist but would it not be possible to produce a car that would operate in more than one car length mode? I don't mean glue 2 cars together, I mean car length -- for example, operate the car at 3m length with all the parking advantages thereunto appertaining, and also at 5m length to advantage the situations that the big cars depend on -- with a lot of space you get more people in when you don't need to fit into a small parking spot, AND you can size down to 3m for more "squeeze" and still have a 5m car that no other natively-small car would be able to rival.

And I don't need the big motor or transmission or lights thing.  I only operate at one speed and never turn or reverse.  And with a properly sized car who needs headlights at night.  If the car is designed right you should be able to see fine without them.  All those extra features are expensive and are for lazy people who don't really know how to drive anyway.

What's your point?

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EOS Bodies / Re: I still don't get the crop debate

« on: April 12, 2012, 08:13:35 AM »

I'm not a physicist but would it not be possible to produce a sensor that would operate in more than one pixel density mode (this is a Canon forum so don't fault me for missing something about the D800 here...).  I don't mean crop I mean pixel density -- for example, operate the sensor at FF 22mp with all the low light advantages thereunto appertaining, and also at FF 38mp to advantage the situations that the crop bodies depend on -- with favorable light, you get higher resolution when you don't need high-ISO, AND you can crop down to 1.6x for more "reach" and still have a 15mp image that no other natively-cropped body would be able to rival. 

I'm not a physicist but would it not be possible to produce a car that would operate in more than one car length mode? I don't mean glue 2 cars together, I mean car length -- for example, operate the car at 3m length with all the parking advantages thereunto appertaining, and also at 5m length to advantage the situations that the big cars depend on -- with a lot of space you get more people in when you don't need to fit into a small parking spot, AND you can size down to 3m for more "squeeze" and still have a 5m car that no other natively-small car would be able to rival.

"I still don't get the crop debate" - now this doesn't come as much as a surprise to me.

Edit: I know I'm bad, but COME ON.

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Lenses / Re: 36+ Mp EOS dSLR (rumored): How do existing EF lenses cope?

« on: February 17, 2012, 11:42:22 AM »

First of all, thanks for your long post, much appreciated.

At f/4 the lens could resolve about 173lp/mm, in which case the maximum useful sensor resolution at APS-C would be about 40mp, or 7716x5155 pixels.

How you get to that approximation will be obvious to me when I read through that link you posted, I suppose? Looking forward to some time to do that.

The EF 50mm f/1.4 lens has an MTF chart that indicates the lens has high contrast but acceptable resolution. Even at its ideal aperture, which appears to be f/4, this lens is not going to resolve as much detail (lp/mm) as a perfect lens. Its about 50% resolution at worst, 86% at best, or on average 68%.  This indicates that an 18.4mp APS-C sensor would be the highest resolution it could reasonably resolve to before the sensor starts consistently outresolving the lens at all apertures.

Ok, now the underlying math here seems to be interesting. Will get back to it.

From the three charts, the finest resolving sensor is in the 50D, maxed out it could (best case) deliver 106lp/mm. The MTF figure for the lens at f4 on the 50D is 2598. Can I, without any reservations, say that this figure equals 87lp/mm? (87lp/mm in turn equals about 10MP resolution on an APS-C.) If so: We now don't know what caused the gap between the sensors maximum 106lp/mm and the actual 87lp/mm, but couldn't it just be that the lens is already maxed out right there?!

Back to your post: 68% of 173lp/mm is 117lp/mm, which is like 18.5MP on APS-C, check. But: Best case you say, the 50/1.4 resolves 86% of a perfect lens. that would be 173lp/mm * 0.86 = 149lp/mm. Where does this come from?

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Lenses / Re: 36+ Mp EOS dSLR (rumored): How do existing EF lenses cope?

« on: February 17, 2012, 11:02:48 AM »

Such a technical and debatable Q &  A. Interesting, though.

I don't think we have reached that limit yet...if it really can be reached. Wouldn't you still get sharper images if, all being equal, the resolving power of the sensor kept improving? In other words, even by using older lenses, if the sensor was "better" it would still improve IQ indefinitely. I think. Shoot, I don't know. 

If you had read the previous posts you'd know the answer to that ;-)

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Lenses / Re: 36+ Mp EOS dSLR (rumored): How do existing EF lenses cope?

« on: February 16, 2012, 04:54:22 AM »

jrista:

It is possible to derive the necessary FF megapixels that would produce the same fineness of detail as an 18mp APS-C sensor if you were interested.

Yes, well I do have the math for that here already, it's not what I meant. I might have gotten a little confused about the right terminology. I'll attach a table with the numbers for a couple of cameras.
That article you posted will take me some time to read through, but I bookmarked it, so thanks!

rav:

A sensor with 1000 height cells is able to resolve about (1000*0.75)/2 = 375 lines.

Ok, now I'm still not sure what to do with that formula to get to my goal.
Let's have a look at these MTF charts:

Canon 50/1.4 on 350D (350D is APS-C and has 2304 height cells):


Canon 50/1.4 on 50D (50D is APS-C and has 3168 height cells):


Canon 50/1.4 on 5D2 (5D2 has 3744 height cells):


Now these MTF figures were derived from images that were taken with 8MP and 15MP (APS-C) and 21MP (FF) bodies. Comparing the 350D and 50D figures, they look kinda (oh well...) the same except being cut off at some point (around 2050) by the 350D. Now that cut-off-point, could that be 2304 height cells minus the AA-filter effect?

The question remains: Are these charts in any way helpful on determining if a sensor with a given pixel size (e.g. 4,31µm) will be outresolved by a certain lens at a certain setting?

Also, given this situation: A certain lens (lets say the 50/1.4) is tested on a certain body (350D). The MTF figures at a certain setting (1.8 ) are clearly lower (1850 LW/PH) than the maximum the camera can resolve (lets say 2050 LW/PH for the 8MP 350D). Can we assume that a higher resolution sensor of the same physical size will not give us any more picture detail? I know the charts above say differently - but why?
(OR could that be due to inaccurate measuring (the tests were a couple of years apart) or assembling deviations (no two lenses are the same)?)

Again, what I found was, that when you take an 18MP picture with the 50/1.4@1.8 on an APS-C camera, downscale it to 8MP and reupscale it to 18MP, there is no loss of detail (at all). Thats why I figured that this lens @1.8 doesnt even outresolve an 8MP APS-C sensor, which I think is supported by the MTF figures above.

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Lenses / Re: 36+ Mp EOS dSLR (rumored): How do existing EF lenses cope?

« on: February 14, 2012, 02:20:52 AM »

Well, yes, a 45MP full frame sensor does have the same pixel size as an 18MP APS-C. But it is actually really hard to out resolve that 7D sensor. Of course, pictures may look really sharp at 100%, but that doesn't mean the sensor got pushed to the limit. I use a 7D, mostly with a Canon 50/f1.4 in the studio, this means optimal lighting conditions. It does a good job at its sweet spot, thats somewhere between f4 and f8, but it gets really soft at 1.8 to hardly usable (for studio pictures) at 1.4. I can reduce a picture taken at 1.8 to 8MP and upscale it again to 18MP, without any loss of detail. And that is for the very center of the frame, the borders are considerably worse. Also note, that the 50/1.2L does not exceed the 1.4 in resolution.

I'm wondering though, how the line widths/ picture height (LW/PH) figures from lense tests translate to sensor resolution.
So 18MP result in 3456 "lines per picture height", while the highest LW/PH scores for APS-C I found were around 2600. If this was a 1:1 conversion, no APS-C sensor above 12MP would be of much use. So I'm guessing that's probably not it. I'd like to find a way to calculate the corresponding sensor resolution to any given lens resolution (and vice versa) OR know why this is not possible. Can anyone help?