Camera Labs

Foveon sensors are a bit off topic (and yes I did read the Sigma thread) but I think it does form part of a wider discussion on what it takes to get the most from an image....of which total resolution, bit counts for processing, types of sensors, as well as the size etc are part of that "performance matrix".

A thread on the nature of all of that would be an interesting one, but I don't regard myself as being qualified to even know where to start on that one....

Given the nature of the consumer at present, 3 x 4.66 mega pixels aint nearly as funky or as marketable as 14 mega pixels and that's where companies like Canon would have to swallow a LOT of brave pills to go down the path. Shareholders get nervous about that sort of thing....

Hi folks,

I've tried to build a little on the content of this thread in the new topic Full-frame or Cropped Sensors: Which is best for Landscapes?.

Bob.

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OM-D E-M5 + ED 12-50mm, H-PS14042E, H-F007014E, L-RS014150E, M.ZUIKO DIGITAL 45mm 1:1.8.
Gitzo GT1541T, Arca-Swiss Z1 DP ball-head.
Astrophotography: TEC 140 'scope, FLI ML16803 camera, ASA DDM60 Pro mount.

Hi folks,

I've been reading another analysis of the pros and cons of full-frame vs. cropped sensors. It's a little wordy (actually, it's a lot wordy) but well worth a look if you find the subject interesting. Check it out here.

Another site which has some great content on the subject is ClarkVision.com. Check out Digital Camera Sensor Performance and Digital Cameras: Does Pixel Size Matter.

Bob.

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OM-D E-M5 + ED 12-50mm, H-PS14042E, H-F007014E, L-RS014150E, M.ZUIKO DIGITAL 45mm 1:1.8.
Gitzo GT1541T, Arca-Swiss Z1 DP ball-head.
Astrophotography: TEC 140 'scope, FLI ML16803 camera, ASA DDM60 Pro mount.

Hi folks,

Well, I've been comparing full-frame sensors against cropped sensors in this thread so why not go the extra mile and look at how crazy the cropped sensors in Compact cameras are? Sorry guys and gals - I love you really.

As a typical example, take the Panasonic Lumix DMC-TZ5, which Gordon reviewed here. From the specification page we see that it can record, in 3:2 aspect ratio, 3552x2368 pixels and that its lens has a focal distance range of 4.7-47mm (35mm Equiv.: 28-280mm). This gives a crop factor of about 6x (280÷47) so implying that the height of the sensor is about 4mm (the 24mm height of a full-frame sensor divided by 6). As a gross error check my post here shows we are in the right ballpark for a "1/2.33 inch" sensor. Remembering that we have a vertical pixel count of 2368 then each of those pixels must be about 1.7μm high.

Now 1.7μm equals 1700nm (nm stands for nanometres, of which 1,000 fit into one μm and 1,000,000 fit into one millimetre). "Why do I care?" I hear you yawn. Well, the light we capture with our cameras has wavelengths ranging from roughly 475nm at the blue end up to 650nm at the red end. It's bad enough, with this type of sensor, that to avoid image softening from diffraction the lens needs to work at roughly f/4 or faster (see this page for more on that) but it seems that the lens has to focus each photon onto an area only three times wider than the wavelengths typical in a sunset.

Frankly, I'm absolutely gob-smacked that the things work at all, though there is plenty of evidence in various images posted here on the forum that they do. It certainly seems as though the pixel count can only be significantly increased from this point on by increasing the size of the sensor, not just from the well worn arguments about high ISO picture noise, but also because we already have pixel sizes not much bigger than the wavelength of the light they are meant to capture. Forget micro-lenses - they'll have to fit waveguides next.

Bob.

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OM-D E-M5 + ED 12-50mm, H-PS14042E, H-F007014E, L-RS014150E, M.ZUIKO DIGITAL 45mm 1:1.8.
Gitzo GT1541T, Arca-Swiss Z1 DP ball-head.
Astrophotography: TEC 140 'scope, FLI ML16803 camera, ASA DDM60 Pro mount.

After reading that story, I was amazed by the size of the pixels, sooo small! Great analysis Bob.
My next camera is going to be full frame, I'm pretty sure. Maybe I should start saving already?

- Bjorn -

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Street and documentary photographer | Google+ | Twitter | Blog | Tumblr

Leica M9-P (my article on Camera Labs) | Leica D-Lux 5 | 50mm Summilux

A few days ago I read a lens review and the result intrigues me. The lens tested was the relatively new Nikkor 60mm AF-S Macro. Here's the link.

http://www.slrgear.com/reviews/showproduct.php/product/1175/cat/12

Now the lens is FX format compatible and was tested both in the D200 (cropped sensor or DX) and the D3 (Full frame sensor or FX).

Most of the results are logical, at least from my humble point of view:
- Less vignetting when used in a DX body.
- Similar figures for CA.
- Similar figures for distortion (slightly worse for the FF)

But the sharpness test surprised me. Results were slightly better on the D200. How is that possible? What am I missing? I thought the large geometry of the photosites of a FF sensor will almost always produce sharper images than a DX with the same lens (and shooting conditions)

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Nikon D90 | AF-S 18-200 VR II | AF-S 35mm f/1.8 | Sigma 10-20mm f/4-5.6 | SB-600 | Gorillapod + Manfrotto 484RC2

Hmm. From one of those sites which actively block links back to us here at CameraLabs.

Without knowing their testing methodology I don't really know the answer but the results look pretty darn good with either body. Don't forget that because of the nature of the Bayer sensor DSLRs have an anti-aliasing filter. It's purpose, as I understand it, is to reduce the effects of moirée patterning, particularly with coloured images. The effect is to soften the image slightly so that light isn't just focussed on a single pixel. If it was then, for instance, if you took a picture of the stars then some would be red, some would be green and some would be blue. The softening is reversed, as far as possible, by the camera's processor.

So, at a guess, maybe the anti-aliasing filter of the D3 is either a little stronger or the default onboard sharpening is a little less aggressive?

Bob.

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OM-D E-M5 + ED 12-50mm, H-PS14042E, H-F007014E, L-RS014150E, M.ZUIKO DIGITAL 45mm 1:1.8.
Gitzo GT1541T, Arca-Swiss Z1 DP ball-head.
Astrophotography: TEC 140 'scope, FLI ML16803 camera, ASA DDM60 Pro mount.

Thanks!

Is there a list of cameralabs blocking sites somewhere in the forum? Anyway I'll be more careful in the future, I already put my leg a few month ago with a link out of dpreview and now this one... Sorry about that.

EDITED: Ok, managed to find the link myself to the thread that discusses the link blocking matter. As I said, I'll be more careful from now on.

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Nikon D90 | AF-S 18-200 VR II | AF-S 35mm f/1.8 | Sigma 10-20mm f/4-5.6 | SB-600 | Gorillapod + Manfrotto 484RC2

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As far as I'm aware the other two sites are dcresource and imaging-resource. Personally, I'm very pleased that Gordon allows us the luxury of self-discipline rather than just blocking links. It also means that, when the situation really warrants it, we can link to those sites. I've done this myself when there has been no other source of relevant information and I needed to illustrate a point.

Bob.

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OM-D E-M5 + ED 12-50mm, H-PS14042E, H-F007014E, L-RS014150E, M.ZUIKO DIGITAL 45mm 1:1.8.
Gitzo GT1541T, Arca-Swiss Z1 DP ball-head.
Astrophotography: TEC 140 'scope, FLI ML16803 camera, ASA DDM60 Pro mount.

Very interesting discussion! Have learned a lot, though I now have more questions than before, hehehehe.

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Canon 5D Mark II
Canon 24-105mm f/4.0 L

I think it's interesting that Canon, for example, have increased their mp on APS-C sensors from 10mp in the 40D, through 15mp in the 50D and now 18mp in the 7D, with very little improvement in the IQ at low ISO levels and more grumblings about IQ at high ISOs. In the past it seemed that an increase in mps would naturally increase the IQ. However, this would suggest that there is an optimal number of pixels on an APS-C sensor (possibly around the 10-12mp range), and thus if you're looking for greater quality, a FF sensor is the only answer.

Probably the best question raised in the thread thus far, as it pertains to a very valid, but unfortunately for many; realistic issue surrounding APS-C Vs Full frame DSLR's: i.e. Affordability.

Moreover, I can't believe that no one has attempted to answer it yet!

The reality is that here in Australia, you won't find a DSLR Full frame body for under $3500 (Body only!) and for many people, it's a very unrealistic and unjustifiable expense unless you're a Professional Photographer. I'm sure that in the U.S. U.K. and Europe it's similarly beyond the budget of many people.

Every time I go into a camera shop quizzing the sales people about the Canon EF-S lenses; I get the same response:

"Why buy an EF-S lens? If you're that serious about photography, why not buy an EF or "L" series lens, that way, when Full Frame DSLR's become cheaper and you upgrade, you'll have lenses for the full frame DSLR. EF-S Lenses don't work on Full Frame DSLR's"

Nice one... Yes, thanks mate.... But when is that going to happen???

Two years from now? A decade from now? Sometime in the next quarter century?

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Canon 500D, EF 50mm F1.4, Tokina 11-16mm F2.8, EF-S 17-55 F2.8 and EF 70-300mm F4-5.6

Hi jimlad74,

Yes, you're right in that cost is certainly an issue but it's not a factor I wanted to introduce into this thread as it has everything to do with the ability of an individual to afford a full-frame camera and nothing at all to do with the capability of the sensors.

As for prices in Australia, a quick search, without due diligence on the e-tailers or any hidden taxes, shows the 24.6MP FF Sony Alpha A850 as available from three sources for between $2265 and $2449.

Bob.

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OM-D E-M5 + ED 12-50mm, H-PS14042E, H-F007014E, L-RS014150E, M.ZUIKO DIGITAL 45mm 1:1.8.
Gitzo GT1541T, Arca-Swiss Z1 DP ball-head.
Astrophotography: TEC 140 'scope, FLI ML16803 camera, ASA DDM60 Pro mount.

When pretty much any technology you buy becomes obsolete within weeks, why worry? Take pictures now and be happy. Upgrade if/when you need to.

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Olympus e-620 / 14-42mm / 40-150mm
Metz 48 AF-1
Kata 3-N-1 20, LowePro Orion Mini, LowePro Nova 2
My Flickr

Hi Bob,

Sorry mate, not trying to hijack the thread, but I thought Dudeskis raised a very valid point.

i.e. It's pretty clear that Full Frame DSLR's are better cameras than DSLR's with cropped frame sensors, but when the hell are they going to be affordable for everyone, so that not just Prof photographers and the wealthy can enjoy their many features and fine image quality?

After all, I've heard from many a camera retailer that; "they will be comming down in price to be almost as affordable as cropped frame sensor DSLR's"



Mate, In retail camera stores in Australia the A850 is still priced at $3500 reccomended retail.

I'm not sure where you're seeing it advertised at over $1000 less than that, however, the cheapest I've seen it so far is at Ted's cameras in Sydney for $3200. This is a discounted price and it's for the body only:

http://www.teds.com.au/www/6/1001102/displayproductcategory/sony-a850--5568790.html

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Canon 500D, EF 50mm F1.4, Tokina 11-16mm F2.8, EF-S 17-55 F2.8 and EF 70-300mm F4-5.6