wfektar

wfektar

Lives in United States United States
Joined on Feb 25, 2010

Comments

Total: 18, showing: 1 – 18
On Rare Canon EF 1200mm f/5.6L USM goes on sale in UK article (218 comments in total)
In reply to:

Robert Newman: For the reported $80K purchase price in the 1990s you could have purchased a hell of telescope with even better optics. It would not have been autofocus, but something like this is not exactly a point and shoot piece of hardware.

@stevo23: I've no idea but I'm sure you're right!

Direct link | Posted on Aug 16, 2014 at 23:26 UTC
On Rare Canon EF 1200mm f/5.6L USM goes on sale in UK article (218 comments in total)
In reply to:

Jogger: Doesnt Zeiss have a lens with a similar focal length?

There are also a Leica 1600/4 Apo-Telyt and a Nikon 1200-1700/5.6-8 zoom (!). But they don't have AF either.

BTW, the Zeiss has an entrance pupil of 425 mm (17 inches for us imperial types) and covers 6x6. No wonder it's so heavy!

Direct link | Posted on Aug 16, 2014 at 00:14 UTC
On Rare Canon EF 1200mm f/5.6L USM goes on sale in UK article (218 comments in total)
In reply to:

Robert Newman: For the reported $80K purchase price in the 1990s you could have purchased a hell of telescope with even better optics. It would not have been autofocus, but something like this is not exactly a point and shoot piece of hardware.

"They are very simple and heavily oriented around reducing coma."

A big refractor is designed for resolution (especially) and light gathering. Aberrations (CA, coma, astigmatism, etc) will reduce resolution so those are of primary consideration. Size and expense generally limit the light gathering.

Everything's a compromise and what the telescope isn't designed for include portability and performance < infinity (where it may well still be excellent). Because portability is not a primary concern, it won't have a telephoto design, which does nothing for a scope except reduce contrast and throughput. AF isn't of any use on a scope, either.

Direct link | Posted on Aug 16, 2014 at 00:10 UTC
On Battle of the titans: Top ball heads tested article (269 comments in total)
In reply to:

basis unus: I'm always wanting to get enlightened of how a high-end ball head compares to a high-end geared head, such as the Arca-Swiss D4.

Ballhead is faster, less precise. Unless of course you need the precision, then the geared head is faster.

Direct link | Posted on Jan 14, 2014 at 01:44 UTC
On Battle of the titans: Top ball heads tested article (269 comments in total)

First, thanks for doing this. Ball size is a perfectly reasonable criterion for comparison, unlike, say, claimed weight ratings. It also seems churlish to to complain about one or two missed mfrs, as a good number are reviewed here.

That said, it is not clear whether the numbers are mfr claims or actually measured. You do note that the load ratings are claimed, as there is no standard for that -- in which case, what is the point of even mentioning them? They cannot be used for comparison. But how about the dimensions, which are easy enough to measure? Also, it seems that the Novoflex ball diameter was measured -- were any of the others?

Direct link | Posted on Jan 14, 2014 at 01:33 UTC as 50th comment | 1 reply
On Canon announces EOS M2 in Japan article (613 comments in total)

Slightly OT: how do you shoot with these things? I can see holding it like a phonecam or P&S with the 22mm in good light, but people are talking about putting telephoto lenses on it. I thought either an EVF or a tilting screen would surely be the first thing to remedy on the M2 -- and Canon surely knows how to do a tilting screen at least -- but perhaps the lack of such things means owners don't think that's a problem? How do you handhold these things?

Direct link | Posted on Dec 4, 2013 at 01:37 UTC as 78th comment | 2 replies
On M50_Viv_f56 photo in wfektar's photo gallery (1 comment in total)

Pentax 50/2 M with Vivitar 2x macro converter

Direct link | Posted on Sep 15, 2013 at 17:40 UTC as 1st comment
On hydrangea-0605 photo in wfektar's photo gallery (1 comment in total)

150/5.6 Caltar IIn, probably f/22 or so. Quickie scan from Delta 100 4x5 sheet film.

Direct link | Posted on Sep 15, 2013 at 17:40 UTC as 1st comment
In reply to:

peevee1: Great job, American business schools. You teach how to gut market-dominant companies to nothing in a few short years.

ManuelVilardeMacedo -- well, it can't possibly be greedy management or stockholders, so who else is left to blame? After all, management gets paid the big bucks for the vision and competence to keep the company at the forefront of the industry, yes? Why else would they be paid better than, say, the scientists and engineers there, who were some of the best in the business?

Direct link | Posted on Aug 22, 2013 at 00:10 UTC
On untitled-03817 photo in wfektar's photo gallery (1 comment in total)

Papilio cresphontes -- Giant Swallowtail
Nikkor 180/2.8 ED at f/2.8

Direct link | Posted on Aug 16, 2013 at 00:45 UTC as 1st comment
On untitled-03819 photo in wfektar's photo gallery (1 comment in total)

Papilio cresphontes -- Giant Swallowtail
Nikkor 180/2.8 ED at f/2.8

Direct link | Posted on Aug 16, 2013 at 00:44 UTC as 1st comment
On Then and now: Photographing the Bay Bridge article (29 comments in total)

Both sets are excellent, although like most here I find the earlier ones more compelling.

As for weight of gear, there's this: http://www.shorpy.com/node/5946. Must be pre-OSHA.

Direct link | Posted on Jul 29, 2013 at 01:47 UTC as 12th comment
In reply to:

Funduro: Blue dot looks like a Nikon D600 oil/dust issue.

No it's not, it's a Hasselblad Saturn, easily distinguished from the D600 by the titanium and silicon trim. Get it right already.

Direct link | Posted on Jul 24, 2013 at 01:26 UTC
In reply to:

Henrik Herranen: One thing worth mentioning is that vertical resolution is halved only on the brightest and darkest areas where there is no tonal overlap in the two half-images. Midtones are at full resolution. And, if you use a less dramatical setting than ISO100/1600 (e.g. ISO100/400), the full-resolution overlap area is larger. Perhaps DPreview would like to correct this in the news blurb?
It's all thoroughly explained in Magic Lantern's documents, with graphs and all.

Good points, both of them.

It's also fair to point out, however, that if you need the 14 EV, it's probably because you're trying to bring out something in the highlights and shadows, beyond what can be done at native resolution. And that the 100/400 combination won't get you 14 stops. This would be a very ingenious approach to get 14 EV if it had not already been demonstrated that you can get that at full resolution.

Direct link | Posted on Jul 19, 2013 at 01:02 UTC

First: thanks for letting us know. Could be interesting.

Second: I realize that this is a press release, which means it is obliged to spend a lot of high sounding words saying practically nothing. In which it succeeds (their note on diffraction is hilarious). So how about a little analysis: how it works (beyond the fluff), what might prevent it from working, that sort of thing. That is, a reality check of all the market-buzzword speak. Thanks!

Direct link | Posted on Feb 5, 2013 at 01:12 UTC as 14th comment
On Just Posted: Canon EOS M preview samples gallery article (130 comments in total)

For the full review would it be possible to try a ~symmetric WA on it? Would be nice to know how much (if any) magenta shift and or corner smearing show up on the M.

(I realize that the M is probably not designed for that. Then again I have no idea what or whom it is designed for.)

Direct link | Posted on Nov 8, 2012 at 01:26 UTC as 13th comment
On Accessory Review: Manfrotto 294 Carbon Fiber Tripod article (50 comments in total)

Welcome to see more reviews, and not just of cameras and lenses.

That said: here's a request. Can you go with measured weights and dimensions, rather than what the mfr claims?

For tripods, how about a stability measure. One possibility is to attach a laser pointer to the hot shoe, point it at a target, and find the spread as the tripod or nearby surface is struck with a known force.

Also for tripods, how about a carrying capacity measure? I have no idea how to do this, but as long as it is reasonable and consistent it should be fine. There are too many meaningless numbers bandied around as it is.

Direct link | Posted on Nov 2, 2012 at 19:46 UTC as 20th comment | 3 replies

OK, format-wise this is basically a u43 camera, only not for reasons of ... what, corporate perverseness? $800 for a somewhat larger than typical u43 with a slow, fixed lens? From a technical performance perspective surely they could have gone u43 and made the lens separately -- those who like the all-in-one kit lens would never have to get anything else anyway, those who don't could access a wide range of existing lenses.

Direct link | Posted on Jan 14, 2012 at 15:42 UTC as 65th comment | 1 reply
Total: 18, showing: 1 – 18