KentG

KentG

Lives in United States MD, United States
Works as a Computer guru
Joined on Aug 5, 2004

Comments

Total: 52, showing: 1 – 20
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On Accessory Review: Drobo Mini RAID article (149 comments in total)
In reply to:

Lukas Gal: Little mistake RAID = redundant array of independent disks not Inexpensive.

Sorry also. In was "inexpensive" from the original designers/inventors of RAID because you could use cheap non-server rated drives in simple RAID systems. Later on the RAID manufacturers changed the wording because they didn't like the idea of inexpensive since RAID systems are not exactly cheap compared to comparable single drive systems. And in actuallity all of the RAID modes up to 5 existed before the name RAID was even published in a paper.

Direct link | Posted on Aug 19, 2014 at 21:09 UTC
On Readers' Showcase: Astrophotography article (43 comments in total)
In reply to:

rrccad: so out of all these, only one would I consider the be "astro-photography" which is a challenging discipline in it's own right.

the rest i consider nightscapes. it's a shame that only one DSO made it on this list, as photographing DSO's is a technological challenge , extreme patience and time far exceeding that of the regular nightscape photograph.

I agree as a 45+ year astrophotographer only #3 and #8 qualify as far as I am concerned. Not to mention I was doing as good as #8 as a junior high school student in 1963 with an RV-6, Practika 35mm, and Plus-X film.
Every astro-imager has to start somewhere but calling these exceptional (except #3 which is decent) would tend to call into question the experience of the person choosing them.

Direct link | Posted on Aug 18, 2014 at 19:19 UTC
On Tamron SP 150-600mm F/5-6.3 Di VC USD Lab Test Review preview (211 comments in total)
In reply to:

racketman: is this lens actually still for sale anywhere?

This lens is brand new not to be confused with anything made previously. It was only announced late in 2013.

Direct link | Posted on Jun 25, 2014 at 21:04 UTC
On Sigma 50mm F1.4 DG HSM | Art Lab Test Review preview (557 comments in total)
In reply to:

ulfie: Size-wise, it's a dang blunderbuss! Kind of negates its low-light, f1.4 shooting abilities if camera shake adds blur due to its size/length, no?

It is actually easier to hold a heavier item steady than a lighter one when you need to point it at something. Just ask any professional shooter. Lighter weight is better when you need to move something you are pointing, like when panning.

Direct link | Posted on May 29, 2014 at 05:51 UTC

Doctor Optic

Direct link | Posted on Apr 2, 2014 at 04:14 UTC as 19th comment
On Battle of the titans: Top ball heads tested article (268 comments in total)
In reply to:

TheDman: I'm not sure how a ball head improves my experience. Why would I not want the control of my pan/tilt that came with the tripod?

I used pan/tilt heads for about 2 decades. Then I bought a big used Graf Studioball so I could mount a Wimberly Sidekick. Since that time 25 years ago everytime I buy a new tripod I chuck the pan/tilt head into a box and put a ballhead on it instead. The only time they come out of that box is when I decide to sell one. I still have that Studioball and it still works fine, even though I have other Arca-plate ones.

Direct link | Posted on Jan 14, 2014 at 05:28 UTC
In reply to:

ceaiu: Why is everyone assuming only Sigma is affected? Maybe they're the only ones (or just the first) to have a fix.

Sorry but both Tokina and Tamron pay licensing fees to just about all the camera makers that don't have an open standard mount. Camera makers, including Nikon, are willing to make a buck just like everyone else. Most don't know that the Big 4 (Canon, Nikon, Minolta, and Pentax) have had a cross licensing agreement on their patents for at least 4 decades.
Sigma on the otherhand, due to the lawsuit they won, can only reverse engineer everything (except open standard mounts). And occasionally when a new camera comes out the OEM may change some responses in the code table and may make Sigma lenses erratic. Whether intentional or not I don't know. At least until Sigma can figure out the changes and redo a firmware fix. As far as I know any Sigma DG lens should be fixable, but I know absolutely that any non-DG lens will not be fixable. I have an analog era Sigma 100-300/4 EX HSM IF in Canon that still works with bodies upto and including the 60D but have not tried it on anything later.

Direct link | Posted on Nov 20, 2013 at 08:10 UTC
On Ten one-of-a-kind cameras from the 21st century article (248 comments in total)
In reply to:

zycamaniac: Not to be picky, but 2000 is the last year of 20th century...

Its true though. There was no year 0 so a decade goes from year 1 to year 10 (1 BC was followed by 1 AD). That means a century (100 years) ends at x000 not x999.

Direct link | Posted on Sep 5, 2013 at 02:09 UTC
On Ten one-of-a-kind cameras from the 21st century article (248 comments in total)
In reply to:

Sordid: What happened to Eye Controlled Focusing by the way?
IMO an extremely useful thing!

Pentax actually did the original R&D on eye-controlled focus but never decided to keep going on it to put it in any of their cameras. Canon picked up the ball and ran with it. One of its issues was on the EOS-3 if you had the AF set to 45 point it would often switch points from the time you wanted the picture till the time you pressed the shutter. As a result many pros just left it in 11-point AF mode. One reason why most DSLRs still have between 9-15 AF points. Too many is often too much.

Direct link | Posted on Sep 5, 2013 at 01:57 UTC
On Sigma 18-35mm F1.8 DC HSM Review preview (333 comments in total)
In reply to:

photogeek: I don't get why people use "normal" zooms — this is the range where it's incredibly easy to "zoom" by just getting closer or farther from the subject. I get UWA and tele zooms, but I haven't owned a "standard" fast zoom for well over a decade now. I just have 35 and 50mm primes instead, and 80% of the time I just leave the 35 on the body.

Well for one thing you won't be getting better image quality with primes, period. And you don't have to miss something by taking time to put a prime on or change one. I used primes for over 30 years. Now I generally use top zooms because there is little difference between them and primes, sorry. A bag full of primes will weigh as much as this lens of course.

Direct link | Posted on Sep 3, 2013 at 05:01 UTC
On Sigma 18-35mm F1.8 DC HSM Review preview (333 comments in total)
In reply to:

falconeyes: I would have been keen to learn about AF consistency using the new 70D's dual pixel live view AF.

You seem to be under the misconception that reviews happen in the present and not in the past. Reviews are just like articles. They get done, then written up, then proofed, and then finally get published. Chances are when this was started they were not in the stores as yet and they only had a pre-production model somewhere in someones possession. And likely not the reviewers.
Commenters need to have a better grasp of reality.

Direct link | Posted on Sep 3, 2013 at 04:51 UTC
In reply to:

Press Correspondent: This is a fake record. I don't know what "antique cameras" this guy owns, pinhole, Polaroids, digicams, or smartphones, or may be he owns a thousand copies of the same model, but in my book "antique camera" stands for film. The world record for having the largest number of film cameras belongs to Richard LaRiviere (USA) who owns 894 DIFFERENT film cameras that he has collected since 1960.

What part of "every CAMERA in the photo is a film camera" don't you get?
Technically, in the USA, antique can be anything older than 25 years ago or more. And all the large cameras in the photo I can identify as large format film because they all have lensboards on them.

Direct link | Posted on Aug 30, 2013 at 04:07 UTC
In reply to:

Press Correspondent: This is a fake record. I don't know what "antique cameras" this guy owns, pinhole, Polaroids, digicams, or smartphones, or may be he owns a thousand copies of the same model, but in my book "antique camera" stands for film. The world record for having the largest number of film cameras belongs to Richard LaRiviere (USA) who owns 894 DIFFERENT film cameras that he has collected since 1960.

Well for a fact every camera in that photo is a film camera. And the Guinness record he set for the second time is "stills" cameras, meaning no video or phones or even video film cameras. Since he inherited 600 from his father in 1977 when there was nothing but film cameras I'm sure he could round up another 300 to beat Richard's supposed record. He has rare cameras going back to the 1890's. As for Richard, his collection record is for motion picture film cameras not stills. That is the only record he holds.

Direct link | Posted on Aug 29, 2013 at 05:25 UTC
In reply to:

oklaphotog: You left out the Dimage EX 1500!

http://www.dpreview.com/reviews/minolta1500

How could you leave out the first non-Kodak DCS non-hybrid DSLR, the 1.75 MP Minolta RD-175 back in 1995?

Direct link | Posted on Aug 21, 2013 at 05:08 UTC
In reply to:

Marco Cinnirella: Tamron's 6 year warranty is sounding more appealing if you are going for a 70-200 f2.8 than chancing it with a Canon, Sony or Nikon lens and, at most, a 2 year warranty?

Just remember that warranties are marketing things these days and have nothing to do with reliability. Its just insurance for the maker actually and perceived reliability.

Direct link | Posted on Aug 14, 2013 at 04:16 UTC
On Sigma USB Dock quick review article (139 comments in total)
In reply to:

AllOtherNamesTaken: So, you still need to manually test every lens for front/back focus? I would have expected that much to be automated. I don't really see the point of this. Basically it just prevents you from having to send your lenses to Sigma for calibration, but instead you pay for it instead of have it done under warranty. It gives some other neat options but I'm not sure how popular this will be.

Every Nikon lens I've ever owned has required zero AF fine tune. I would expect the same if paying big money for one of the nice new Sigmas.

Then obviously you don't have much experience, otherwise Nikon would not have put AF tuning in their cameras either. Every camera maker had the same problems when they went to 10 MP from 6 MP, every one of them. AF sensor technology was not up to par during that time. Plus there are reasons today when you might want to play with the front and back focus to change the amount of each for a particular shot.
As for the Sigma USB Dock of course you have to test it out. The camera is what decides the focus point not the lens. The Dock does not have a built in test sensor.

Direct link | Posted on Aug 13, 2013 at 04:38 UTC
On Sigma USB Dock quick review article (139 comments in total)
In reply to:

Spectro: The reason you even need this for sigma and not like tokina or tamron is that they reverse engineer their af for Nikon, canon, Sony,etc. Tamron and tokina liencse with the camera makers. My big local camera store refuse to carry sigma of issues. Maybe this USB will help with my sigma 85mm 1.4 jerky af issues.

The other companies do in fact license the mount technology from Nikon, Canon, Pentax, and Sony (in fact most of the big Nikon pro telephotos are built in a Tokina plant or were). Sigma doesn't because they are not allowed to. They won a big suit in the film days that broke the monopoly on the proprietary nature of each camera makers mounts. So none of the Big 4 will sell them a license and the original suit approved a method they used to reverse engineer the electronic protocols. The original suit broke any proprietary nature on the mechanical specs of the mount at the time. More that likely since Sigma actually kept the third party industry alive we would be paying as much as 2x for factory lenses these days. In fact the only reason they sell lens technology licenses at all is to allow others to compete with Sigma.

Direct link | Posted on Aug 13, 2013 at 04:18 UTC
On Sigma 17-70mm f/2.8-4 DC Macro OS HSM | C review preview (89 comments in total)
In reply to:

forpetessake: I tested that lens, it's rather mediocre performer. Resolution is poor on both ends. True, it does get much better closed one stop, but who needs a big and heavy f/4-5.6 lens. There is also some glow and loss of contrast in high contrast transitions, pretty unpleasant to look at. Color-wise it's probably neutral, but still somehow images look drab. The images don't really look any better than from cheap kit zooms. And somebody needs to check its T-stop, it probably loses an extra 1/2 stop at f/4.

They have made 3 versions of the 17-70/2.8-4 and all have different optical formulas.

Direct link | Posted on Aug 6, 2013 at 04:14 UTC
On Sigma 17-70mm f/2.8-4 DC Macro OS HSM | C review preview (89 comments in total)
In reply to:

jorg14: I'm very confused. I've been shooting macro at 1-5cm for years and have had my photos published throughout the states. This length lets me shoot with one hand while stabilize the flowers with the other, plus renders the background nice and blurry while keeping much of the flower in focus. Of course I'm using a Compact (G series or Nikon P7700) for most of my work. I have no problems with light, as simply turn the subject sideways to the sun until well lite which often gives interesting lighting effects. So why exactly is this 'short' 22cm, (10x as long as I use) a problem?

A macro with a short working distance is a problem when shooting live creatures like insects because they can see the lens and get spooked. Main reason most insect shooters use macros from around 100mm and longer.

Direct link | Posted on Aug 6, 2013 at 04:12 UTC
On Sigma 17-70mm f/2.8-4 DC Macro OS HSM | C review preview (89 comments in total)
In reply to:

Peter Gregg: How do you know if a lens like this will work on Canon's new 70D. Canon has list of "approved" lenses for a reason. With 3rd party lenses work on the new Canon 70D?

Canon has a set of "approved" lenses to try and keep you from going out and finding a 3rd party lens that works just as good for 1/2 the money. That may mean that Sigma will have to reverse engineer any new camera code sequences and publish a firmware update you can load yourself with the USB Dock.

Direct link | Posted on Aug 6, 2013 at 04:09 UTC
Total: 52, showing: 1 – 20
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