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: 181, showing: 81 – 100
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On article What is equivalence and why should I care? (2341 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?

Link | Posted on Jul 9, 2014 at 03:04 UTC as 275th comment | 5 replies
On article Tamron SP 150-600mm F/5-6.3 Di VC USD Lab Test Review (268 comments in total)

Resuming: A good trash.

Link | Posted on Jun 26, 2014 at 01:54 UTC as 79th 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

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.

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

Tamron knows Panasonic will launch sensor stabilization

Link | Posted on Jun 19, 2014 at 16:36 UTC as 28th 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.

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

Pure lol.

Link | Posted on Jun 13, 2014 at 19:30 UTC as 29th comment
On article Sigma 50mm F1.4 DG HSM review (591 comments in total)

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

Link | Posted on Apr 17, 2014 at 15:40 UTC as 186th 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.

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.

Link | Posted on Jan 24, 2014 at 15:35 UTC as 16th comment
On article Nokia ad takes us inside the new Lumia 1020 (116 comments in total)

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

Link | Posted on Aug 12, 2013 at 01:55 UTC as 22nd comment

What about its video capability?

Link | Posted on Jul 17, 2013 at 00:26 UTC as 22nd comment
On article French student creates SLR using 3D printer (156 comments in total)

I do better carving wood.

Link | Posted on Jul 8, 2013 at 21:34 UTC as 58th comment | 1 reply
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?

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.

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

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

Canon should think on things more affordable.

Link | Posted on May 14, 2013 at 17:03 UTC as 57th comment | 4 replies

Sheet. I will remain on the ground.

Link | Posted on May 8, 2013 at 03:13 UTC as 114th comment

Seems to be Aedes aegypti the Dengue vector.

Link | Posted on Jan 8, 2013 at 02:20 UTC as 3rd comment
In reply to:

Ruy Penalva: More important than examine the IQ of this lens is to analyze its weak internal construction. Avoid it.

Read Roger Cicala description before say the above. Optical frontal elements fixed with glue!

Link | Posted on Nov 19, 2012 at 14:13 UTC
Total: 181, showing: 81 – 100
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