January 26, 2015, 11:01:42 PM

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Messages - rs

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EOS Bodies / Re: 50mp Cameras Coming in March [CR1]
« on: January 24, 2015, 11:01:33 AM »
Explanation please? What is a low pass filter in this context? What is it for and if it's necessary, why build a camera without one? Is it the same as an anti-aliasing filter (another term I don't understand...)
Yes, they are one and the same thing.

Explanation: http://en.m.wikipedia.org/wiki/Low-pass_filter

EOS Bodies / Re: High Megapixel Camera Coming in 2015 [CR3]
« on: January 22, 2015, 08:39:33 AM »
Look at all of the tests that websites such as dpreview do. Do they judge a camera's IQ by how well it focuses? Or do they judge it by how well a camera correctly captures and reproduces test patterns, colour charts, etc?

IQ is a property of the camera...

Yes, IQ is a property of the camera and lens.

Those tests to which you refer are judging the sensor, which is one of multiple components that contribute to the image quality of a camera.

IQ is a property of the sensor.

Of course you can keep your view but every camera reviewer out there on the Internet disagrees with you.

Yes, you're 100% correct. Lenses have zero influence on IQ, AF has zero influence on IQ and all the other features of a camera such as metering, shutter lag and FPS don't cobtribute anything towards creating a better image. And, the only differentiator between the IQ of any film cameras was which film they were loaded with.  ::)

Lenses / Re: TS-E Depth of Field newbie question
« on: January 13, 2015, 01:12:39 AM »
Unfortunately not.

For starters you'd be using a lens with no zoom, a slow aperture and no AF - not exactly a good recipe for sports. Then, throw in all the other manual settings such as the tilt and the rotation of the elements, and you end up with a locked into one position on a tripod solution.

It is a misconception that a TS lens increases DoF. It does not. Like any lens, it has a plane of focus, and the depth of what is acceptably in focus is controlled by the aperture (and subject distance). How it differs is you can angle this plane of focus so it is no longer parallel to the sensor. This means that for two dimensional objects such as a peice of paper, even at an angle, with lots of patience, tweaking, experience, and magnified live view, you could potentially get all of it to lie perfectly within the plane of focus. Move the camera a touch, and you'd need to readjust it all to get it back. And to make matters worse, if that was a three dimensional object, everything above or below the piece of paper would be out of focus.

If you really want an approximation of everything in focus in a three dimensional action scene, try either using very small apertures with very high ISO's, or do the equivalent of such by using a small sensor camera like an iPhone.

EOS Bodies / Re: A New xxD DSLR Coming From Canon [CR1]
« on: January 12, 2015, 05:05:24 PM »
Quick, check out the leaked page before Canon UK notice and take it offline again ;)
Leaked page? If it was posted 12 years ago, then yes  ::)

Lenses / Re: New Canon 100-400mm Mk2 lens with 2x extender mk3
« on: January 07, 2015, 01:15:47 AM »
I have tried this but it did not seem to be any better. Haven't used a cable release but I've set it to 10s delay before firing.
The idea of using liveview AF and the cable release is you can invoke autofocus without physically touching the camera - this allows you to largely work around any stability issues with your tripod.

Software & Accessories / Re: 6D Eyepiece Magnifier options?
« on: January 04, 2015, 07:18:33 PM »
Canon don't make anything, and if you find a third party eyepiece magnifier, chances are it will only show you the centre of the frame - any gains made in manual focusing will be offset by losses in composition.

How about another tack - standard focus screens don't reveal the full extend of how narrow the DoF is with wide aperture lenses, so what about the Canon Eg-S focus screen? Or even a third party split prism focus screen, and put up with slightly unreliable metering? Or, just use live view?

PowerShot / Re: New PowerShot(s) for CES Next Week [CR1]
« on: January 02, 2015, 07:02:49 PM »
That's kind of weak for a superzoom, and not much on the wide end either, but if it has excellent IQ (especially at f2) then I guess it still has potential.
Compared to the competition, it's class leading. There are currently two 1" sensored large zoom cameras out there.

The Sony RX10 with a 24-200 equivalent zoom, and a fixed f2.8 aperture. This rumoured spec clearly beats that.

And then there's the Panasonic FZ1000 with a 25-400 equivalent lens with a variable f2.8 to f4 aperture. This rumoured camera only has half the telephoto reach, but it lets in four times as much light at full zoom.

PowerShot / Re: New PowerShot(s) for CES Next Week [CR1]
« on: January 02, 2015, 06:19:54 PM »
I'm guessing it's actually an 8.9-74/1.4-2.0 lens. Otherwise that 100mm entrance pupil and 65mm equivalent wide end would make it an unwieldy compact...

MTF charts don't reveal any information about distortion. However, there are real life distortion measurements you can look at, such as this:


EOS Bodies / Re: Canon 5DIV: 36 MP US $ 3799 TBA in March 2015
« on: November 23, 2014, 08:15:46 AM »
I wouldn't bet on 36MP.

DxOMark gives some FF lenses (600mm mkII, 24-70mm mkII) as much as 13-14MP on the 70D. If the lens' corner IQ was as good as the center, they would produce a wee under 36MP on FF.

Taking DxO's ratings as gospel is almost in the same league as doing the same with KR. OK, it's not that bad  ::)

Lenses / Re: 60d lense options ?
« on: November 23, 2014, 05:28:28 AM »
The three lenses you've listed all exist as they fill very different needs. Amongst the countless lenses that could be added to your list is the highly acclaimed Canon 17-55/2.8 IS, but again, that's aimed at a different market to the other three. If you want to get any sort of meaningful advice, you'll need to answer the following:

What subjects are you planning on shooting with your new lens?
What lens/lenses have you already got?
What's your budget?
What focal lengths do you need?
Do you want a fast lens to stop action?
What are you looking to gain from this new lens?

EOS Bodies / Re: Canon 5DIV: 36 MP US $ 3799 TBA in March 2015
« on: November 23, 2014, 01:37:46 AM »
Very credible and consistent spec list. Definitely not just poorly thought out click bait:


Two CF slots.


30.0 oz. (850g) with battery and SD card.

EOS Bodies / Re: Patent: Canon EF-S 11-24mm f/3.5-4.5
« on: November 20, 2014, 03:05:25 AM »

Also the back focus of just 3.26mm means its not even EF-S, as that has a 44.0mm flange distance and a mirror box to clear.

This appears to be an EF-M lens.

+1 I don't think it's a coincidence that this patent coincides with rumours of a new EOS-M.

kind of moronic because there's already an exceptional 11-22mm EF-M out there.

Moronic or not, read the patent. How can it mount onto a DSLR with that BF?

Please remember that just because there is a patent, it doesn't mean this lens will become a production reality.

EOS Bodies / Re: Patent: Canon EF-S 11-24mm f/3.5-4.5
« on: November 18, 2014, 10:33:25 AM »
Yeah, I'd be very interested if it's EF.  I use my 10-22 almost every day, and wouldn't be at all interested in losing anything off the wide end.
If you want EF 11-24, there's the rumoured upcoming EF 11-24/4L that you should keep a look out for.

This is definitely not EF. The image height (radius of imaging circle, half the diagonal) in this patent is 13.66mm. It is enough for a 1.6x crop with its 27mm diagonal, but not enough for a 1.0x sensor with its 43.3mm diagonal.

Also the back focus of just 3.26mm means its not even EF-S, as that has a 44.0mm flange distance and a mirror box to clear.

This appears to be an EF-M lens.

EOS Bodies - For Stills / Re: Is IQ better with smaller files?
« on: November 18, 2014, 10:00:57 AM »
The S/N ratio is unaffected. There is no less noise in the low resolution image. What is going on is a difference in how much you can enlarge the resulting image.

If you view both images at a 1:1 pixel ratio on your display, there will be more noise visible in the high resolution image. But at the same time, more detail is visible. This is because the extra resolution has allowed you to enlarge that image to a much greater extent.

What you have to do is forget about what extra noise and detail you can see at a 1:1 pixel ratio, but look at them both with the same enlargement - that is, print them both at the same size, or display them both on a monitor at the same size. Then you'll quickly come to realise that there is zero difference in the amount of noise. The only difference is the higher resolution image gives you more latitude for enlargement before pixelation sets it.

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