rhlpetrus

rhlpetrus

Lives in Brazil Campinas, Brazil
Works as a math professor
Joined on May 4, 2007

Comments

Total: 620, showing: 1 – 20
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On Nikon D810A: An astrophotographer's perspective article (113 comments in total)

Astro or not astro, very interesting landscape photography. Very far from my own style and needs, thus much more interesting to me than most other stuff I see more frequently. Enormous effort for each image, I can appreciate that as well. Thanks for posting it.

Direct link | Posted on Jul 7, 2015 at 22:56 UTC as 15th comment | 2 replies
On Nikon offers AF-S DX Nikkor 16-80mm F2.8-4E ED VR article (329 comments in total)
In reply to:

oselimg: Ok, it has f2.8-4, credit given where it's due. This is an "enthusiast" lens not a main stream one therefore $1060 ok. However it's only 1/2 stop faster at the wide end and 1 stop at the long end compared to mainstream alternatives which in most cases is not significant. No wedding photographer will dare shooting with f4 at the longer end. if it had f2.8 throughout it would have made sense especially at the long end and even slightly bigger premium would've been justified if it were, performance wise, the "jack of all trades". With todays sensor performances I think the target audience wouldn't hesitate increasing the ISO one step instead of paying $$$ premium. 7 blades aperture is another Achilles heel for this zoom.

@samfan: agreed, the 18-70mm was my standard zoom with the D80, such a great combination. Nikon finally has a true heir to that lens.

Direct link | Posted on Jul 2, 2015 at 15:37 UTC
On Nikon offers AF-S DX Nikkor 16-80mm F2.8-4E ED VR article (329 comments in total)
In reply to:

brownie314: Why Nikon! Why make a lens that already exists for DX. The Sigma 17-70 2.8-4 is an excellent lens that can be had for less than half the price of this Nikon lens. Why not give us a nice, compact 24mm 2.8 (or 2.4) prime! It would make the D3300 and D5500 very compact. But no.

I own the 17-50 f/2.8 Sigma. Decent lens, but not up to Nikon standards re AF and resistance to flare (and that greenish flare Sigmas produce is so ugly!!!). If I were not waiting to see the new FF ML that has been rumored I might get it, but I can wait. Cheers!

Direct link | Posted on Jul 2, 2015 at 15:33 UTC
On Leica Q First Impressions Review preview (564 comments in total)

Question: do the crop factors for 35mm and 50mm show as full view in the EVF? Or some sort of frame crop like the Ms?

Direct link | Posted on Jun 15, 2015 at 00:19 UTC as 35th comment | 1 reply
On Leica Q First Impressions Review preview (564 comments in total)

I really liked the RAW performance of this camera, compared to the FF standard set by the D750. The lens seems to be outstanding in the studio scene shots.

Too bad the price is ....

Direct link | Posted on Jun 15, 2015 at 00:18 UTC as 36th comment
On Nikon D7200 First Impressions Review preview (1114 comments in total)
In reply to:

califleftyb: I bought the D7100 and found the images to be rather noisy. After looking at the sensor specs I saw why - the sensor's pixel pitch was one of the smallest of any Nikon camera, at 3.9µ similar to the D3200. In fact Nikon reduced the pixel pitch from the D7000 (from 4.8). I was rather shocked at this ploy to get "more megapixels" to induce more sales. I wish DPReview added this information to the specs when they do a review. I suggest anyone looking to upgrade to any Nikon camera look at this number carefully if it is an important issue to you.

Is it true that this carries a Sony sensor? If true, then maybe it'll at least match the D7000's one in low ISO IQ, still the unmatched sensor in that respect, APS-C format.

Direct link | Posted on Mar 2, 2015 at 21:53 UTC
On Nikon D7200 First Impressions Review preview (1114 comments in total)
In reply to:

Aur: I'll never undererstand the argument some ppl use about weather sealing. Afaik, none of the DX lenses have weather sealing, only FX lenses have it. Are people really putting $2000 lenses on a crop sensor?

If you want weather sealing, you should be looking at Pentax, they have $200-$1000 lenses with weather sealing. Nikon only has weather sealing in their most expensive lenses, and even on those, Nikon seems very reluctant to tell users how much they can withstand, the info is really hard to find. Pentax has no problem telling it's users which lenses are fully weather proof and they even show it off in promotional videos.

Ppl take these cameras on safaris and then complain about dust on their pictures with Nikons, yes..because none of the DX lenses are weather sealed, so your body being weather sealed is completely irrelevant.

I have the D7000 and my main landscape lens is the lowly 12-24 f/4 lens. Once I went with friends, both DPR members, on a Lake District shooting adventure, late March or early April. As fit, it rained through the day, sometimes quite heavily. I had to wipe the lens front element quite a few times with a piece of microfiber cloth to get the water out, so you can imagine the whole camera was getting very wet. It never failed, no fog on VF, no issues with lens. The only care was to leave them close to a warm area at the end of the long day. This issue is overstated and used by people who likely never venture out on a wet day.

Direct link | Posted on Mar 2, 2015 at 21:44 UTC
In reply to:

deep7: It looks almost too simple. An interesting concept. I hope it does well as it gives us more options in the market.

I think this is concept, there will be buttons in the back for the usual stuff.

Direct link | Posted on Feb 24, 2015 at 20:12 UTC

This is what Leica should be doing, an all electronic RF system at a reasonable price. If the IQ is good, this could be a very interesting camera for those with M lenses that find current Leica prices beyond their reach.

Direct link | Posted on Feb 24, 2015 at 20:10 UTC as 138th comment | 3 replies

Very nice that a photography company will invest in such a specialized HQ product, makes Nikon users quite comfortable with the direction Nikon have been taking in terms of HQ photography. That's what brought them to the top of the photo world.

Direct link | Posted on Feb 10, 2015 at 14:04 UTC as 63rd comment | 3 replies
In reply to:

mpgxsvcd: I have been saying it for years that Olympus’s live time and Panasonic’s constant preview functions make them ideal for Astro Photography. Now that Nikon slapped the “Astrophotography” label on a camera everyone is also singing the praises of those functions.

I have no doubt this new Nikon Astro camera will be great. However, let me propose some reasons why something like a modified Olympus E-PL5 is a better choice.

1. The E-PL5 has the excellent Sony sensor for outstanding long exposure high ISO photos.
2. The crop sensor is actually better than full frame because full frame requires a much bigger and more expensive scope to cover the full frame.
3. It has the articulated LCD.
4. Cost – A modified E-PL5(Less than $400 fully modified) is about 1/10 the cost of the 810a and a modified camera is even more sensitive to Ha than this astronomy geared Nikon.

I am not saying this camera is not a good choice. However, there are much less expensive options that can achieve the same results.

You forget that Nikon also makes lots of other relevant components that would make it interesting to have a Nikon body for AP. Besides, there are technical aspects in the sensor that make it a likely choice for AP.

Direct link | Posted on Feb 10, 2015 at 14:01 UTC
On Canon EOS 5DS / SR First Impressions Review preview (3410 comments in total)
In reply to:

Earthlight: The resolution as such is fantastic and I welcome it with open arms. Those claiming diffraction ruins everything need to educate themselves on the matter. Those who actually need the res will know how to handle it.

But...

The dynamic range is the same as with 5D3...? What about pattern noise? Still there too?

By Dr_Jon (22 min ago)
That is pixel-level DR (or so they say), you have 2.5x the pixels to average out the noise over.

Better study a bit about what that means ...

Direct link | Posted on Feb 6, 2015 at 11:23 UTC

If the optics are decent, interesting alternative, even for APS-C (Nikon DX).

Direct link | Posted on Jan 24, 2015 at 22:46 UTC as 15th comment | 1 reply
On Nikon D750 flare investigated: Why we're not worried article (365 comments in total)
In reply to:

DDWD10: If I could just play Devil's Advocate for a second.

Both the stepped flare and AF calibration issues would be impossible in a MILC. More complicated machines increase the likelihood of quality control issues. Glad to see Nikon is stepping up to the plate and taking care of this.

"The only camera makers not having new issues are those who don't produce new products."

Or those that sell so little that there are no users available to test cameras.

Direct link | Posted on Jan 21, 2015 at 20:20 UTC
On Nikon D750 flare investigated: Why we're not worried article (365 comments in total)
In reply to:

Ramjager: Let me guess if it was a Canon camera from DPR's perspective it would be another nail in the coffin.
Instead it's Nikon but hey it's ok...
Let me guess who is paying the bills..

Oh my, more conspiracy going on ...

Direct link | Posted on Jan 21, 2015 at 20:17 UTC
On Nikon D750 flare investigated: Why we're not worried article (365 comments in total)
In reply to:

Artpt: Directed @Rishi, do you think manufacturers will get sophisticated enough to have camera bodies fine tune their PDAF with various lens using the CDAF in camera...much like manual white balance with indoor lighting?

I rough comparison is a printer's/scanner's calibration process...

Just a thought?...and as always, thanks.

Art

The latter cameras from Nikon and Canon seem to require less AF microtuning with newer lenses, so maybe this is already going on, maybe not a full-fledged tuning, but some sort of generic FT.

Direct link | Posted on Jan 21, 2015 at 20:16 UTC
On Nikon D750 flare investigated: Why we're not worried article (365 comments in total)
In reply to:

AbrasiveReducer: Say you were working for a small company and not getting the publicity you felt was deserved...Instead of spending tons of money on pure photography, leave a screw out somewhere and your product will be in the news every day for months. All for a problem that is easily fixed. And between shows, too when there is no other news.

Paranoid and conspiratorial minds abound around the internet.

Direct link | Posted on Jan 21, 2015 at 20:12 UTC
On Nikon D750 flare investigated: Why we're not worried article (365 comments in total)
In reply to:

Eleson: "Much of the talk on the internet since the launch of the D750 has been about flare, "
I would disagree. At least equal much talk have been about how Nikon would handle this (non-) issue.
The track record with Oil and left side AF has been the reason for this.
- And the handling on this matter from Nikon have been 2nd to none and a really good statement in customer care.

Totally agree, from the start, after seeing how many othe rbodies showed the same effect, I felt this was an overblown internet affair. Nikon, scolded for their unproper handling of D600 issue, mainly, responded in a way I find a bit unexpected. Good for us Nikon users, actually, so I don´t condemn the whistle-blowers, even those with some paranoid tendencies.

Direct link | Posted on Jan 21, 2015 at 20:10 UTC
On Nikon D750 Review preview (1935 comments in total)
In reply to:

Horshack: Very nice follow-up on the flare issue Rishi. Ever since you started contributing to the editorial content on the site the depth of technical information has increased markedly. I just wanted to say thanks and to let you know your contribution hasn't gone unnoticed.

Indeed, KUTGJ! Hi Phil!

Direct link | Posted on Jan 21, 2015 at 11:32 UTC
In reply to:

sfpeter: My 750 is in the affected range, and after some trial and error I've been able to reproduce it. Use a wide open prime, in my case a 50mm f/1.4, in live view. Point a bright light source at the lens from high up and gradually move it down. At about a 45 degree angle, give or take 2-3 degrees, it will appear. You're basically pointing it right at the AF sensor.

How big this is depends on the type of shooting you do--and as been repeated ad nauseum, it's not flare but an internal reflection off the AF sensor, and in a very limited 2-3 degree range. The "dark band" would be completely black if something was blocking it.

If I shot video all the time and used flare this would be an issue, I'm not sure if this is important enough for me to bother--I haven't seen it any actual photos I've taken.

Unless you are like me and, when updating, keep cameras as collecting items, I'd do it. It'll affect its resale value.

Direct link | Posted on Jan 20, 2015 at 15:29 UTC
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