Ruy Penalva

Ruy Penalva

Lives in Brazil Lauro de Freitas Bahia, Brazil
Works as a Medical Doctor
Joined on Jun 28, 2010
About me:

Ruy Penalva de Faria Neto

Comments

Total: 106, showing: 1 – 20
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On What is equivalence and why should I care? article (1756 comments in total)

Butler. My question. It is told that f/8 is the optimum limit to diffraction in digital sensor. My question to you is: The shift in aperture equivalence is followed by a decrease in diffraction too? In other words. Take a Panasonic lens with an upper f/5.6 aperture. The equivalent aperture of that lens would be f/11.2. How that real aperture of f/5.6 (or 11.2 equivalent) behaves in regard to diffraction? Is diffraction related to amount or to intensity of light?

Direct link | Posted on Jul 9, 2014 at 03:04 UTC as 121st comment | 5 replies
On Tamron SP 150-600mm F/5-6.3 Di VC USD Lab Test Review preview (192 comments in total)

Resuming: A good trash.

Direct link | Posted on Jun 26, 2014 at 01:54 UTC as 37th comment
In reply to:

Ruy Penalva: Tamron knows Panasonic will launch sensor stabilization

The shift of Tamron toward a non stabilized zoom lens is a clue to that rumor

Direct link | Posted on Jun 20, 2014 at 01:28 UTC
In reply to:

Ruy Penalva: Tamron knows Panasonic will launch sensor stabilization

Probably will adopt it universally in all MFT, I mean.

Direct link | Posted on Jun 19, 2014 at 21:37 UTC

Tamron knows Panasonic will launch sensor stabilization

Direct link | Posted on Jun 19, 2014 at 16:36 UTC as 27th comment | 4 replies
In reply to:

Shadowww: For those who are curious about focal length/aperture equivalents yet are too lazy to calculate: it's 88-320mm f/7.2-10 equivalent.

I think this concept of aperture equivalence should be discussed better from an optical point of view. Although focal equivalence is obvious in magnification, we don't feel that huge lack of light in cropped sensors as compared to 35mm sensor. As we know f/8.0 is the upper limit of optimal refraction in digital sensor, every cropped sensor would give poor results. And that is not the case. May be that is true only in terms of DoF but not in the amount of light that reach the photo-sites.

Direct link | Posted on Jun 17, 2014 at 21:53 UTC

Pure lol.

Direct link | Posted on Jun 13, 2014 at 19:30 UTC as 28th comment
On Sigma 50mm F1.4 DG HSM | Art Lab Test Review preview (545 comments in total)

The price of the lens in Side by Side comparison is wrong.

Direct link | Posted on Apr 17, 2014 at 15:40 UTC as 166th comment
In reply to:

Lan: In other news, Sony also announced Europe falling off the face of the planet ;)

What about 50p?

I think it can both NTSC and PAL along with 24P. It is described in Sony hot-site.

The sensor reads out image data from every pixel, even during Full HD and 4K*2 movie output, and enables recording and output of Full HD movies at 60p (50p), 60i (50i), 30p (25p) and 24p frame rates, as well as output of 4K movies at a 30p or 24p frame rate, with both resolutions available at both full-frame and APS-C (Super 35mm equivalent) size.

Direct link | Posted on Apr 7, 2014 at 01:50 UTC

Very practical. Is it a filter or a curtain? Probably Fred of Flintstones will adopt it.

Direct link | Posted on Jan 24, 2014 at 15:35 UTC as 14th comment
On Nokia ad takes us inside the new Lumia 1020 article (116 comments in total)

It's just time true compact cameras talk like cell phone shoot.

Direct link | Posted on Aug 12, 2013 at 01:55 UTC as 22nd comment
On Preview:canon-eos-70d (1333 comments in total)

What do you mean by:
"Canon has made no fewer than 156 EF lens models in the 26 years since the EOS system first appeared, and it says that 103 of them fully support Dual Pixel CMOS AF, including all current lenses"

This Dual Pixel support means continuous video focus in those 103 lenses?

Posted on Aug 7, 2013 at 03:13 UTC as 348th comment | 2 replies

What about its video capability?

Direct link | Posted on Jul 17, 2013 at 00:26 UTC as 21st comment
On French student creates SLR using 3D printer article (156 comments in total)

I do better carving wood.

Direct link | Posted on Jul 8, 2013 at 21:34 UTC as 58th comment | 1 reply
On Sigma 18-35mm F1.8 DC HSM Preview preview (352 comments in total)

Why not one like that to a full frame sensor?

Direct link | Posted on Jun 14, 2013 at 22:28 UTC as 38th comment | 2 replies
In reply to:

Ruy Penalva: The built quality cannot be very good since some inner glasses are fixed with glue as shown by Roger Cicala. This could means easy dis-adjustment.

I ask my self how DP could speak of good built quality when DP did know of these pitfalls in built construction such as - industrial Josh152's glue - use in front elements?

Additionally, how DP could talk about the good environmental seal with only few hours of testing?

Where are the tests made to show good built and environmental qualities?

Direct link | Posted on May 21, 2013 at 00:47 UTC

The built quality cannot be very good since some inner glasses are fixed with glue as shown by Roger Cicala. This could means easy dis-adjustment.

Direct link | Posted on May 20, 2013 at 21:56 UTC as 33rd comment | 5 replies
In reply to:

Ruy Penalva: Canon should think on things more affordable.

I hope all of you can afford to buy one like myself can. That is not a strong reason to not find it pricey, almost half a car price. I have enough money but I earn it honestly so... toidI

Direct link | Posted on May 15, 2013 at 02:29 UTC

Canon should think on things more affordable.

Direct link | Posted on May 14, 2013 at 17:03 UTC as 55th comment | 4 replies

Sheet. I will remain on the ground.

Direct link | Posted on May 8, 2013 at 03:13 UTC as 101st comment
Total: 106, showing: 1 – 20
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