BJL

BJL

Lives in United States United States
Joined on Dec 17, 2002
About me:

Olympus E-520, E-1, 14-54 f/2.8-3.5, 50-200 f/2.8-3.5
Olympus C2040
Canon Elan II/EOS-50, 28-105 f/3.5-4.5
Pentax K1000
Kodak Instamatic
First camera: Kodak Brownie

Stabilization by Manfrotto

Comments

Total: 216, showing: 21 – 40
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On AJA enters cinema camera market with 4K Cion article (28 comments in total)
In reply to:

BJL: Why is the sensor called "APS-C" size, when its output is in the wide-screen 1.89:1 shape of cinema 4K (4096x2160), not the 3:2 of "APS-C", and is likely instead to be something closer to Super 35mm format?

It is strange to describe a digital motion camera's format in terms of a failed still camera film format of different shape (3:2) when there is are well-established motion camera formats like Super 35mm that describe the situation better.

Agreed that "super 35mm" is used loosely when describing video sensors. But it makes more sense to me to indicate roughly the format of a video sensor by comparing to a similar, well-known, widely used motion picture format than to compare to an obscure, failed still film camera format in a quite different shape: this sensor is in the roughly 1.9:1 shape of cine-4K, 4096x2160.

Direct link | Posted on Apr 10, 2014 at 00:09 UTC
In reply to:

Joseph S Wisniewski: Wonder how many uFT lenses will cover the 25.3mm Super35 image circle.

Weird. If Panasonic hadn't recently dumped all their JVC Kenwood stock (they were JVC's largest single investor for half a century) I'd say "oh look, a Panasonic subsidiary has joined four thirds".

But right now, it makes no sense.

P. S. Also "Super 35mm" is being used as loosely as "APS-C" these days. The actual sensor seems to have a 23.7mm diagonal for the cine-4K format, which is only 1.2mm more than the 22.5mm diagonal of official 4/3" format (18x13.5mm).

Direct link | Posted on Apr 9, 2014 at 22:17 UTC
In reply to:

dark goob: This is just wrong. Super35 is 24.9x16.6.

21x12 is the same thing BlackMagic's Production Camera uses.

For Reference the GH2's multi-aspect sensor is 18.9x10.6mm at 16:9.

The phrase "Super 35mm" is being used with digital video the way "APS-C" is used with digital still cameras: as a rough indication of the size using a hopefully familiar film format, which Super 35mm is for cinema and video professionals.

I do not see many people complaining about using "APS-C" to describe sensor formats as small as Canon's 22.3x14.9mm, when the actual APS-C film format is 25.1x16.7mm, larger than any "APS-C" sensor.

Direct link | Posted on Apr 9, 2014 at 22:13 UTC
On AJA enters cinema camera market with 4K Cion article (28 comments in total)
In reply to:

BJL: Why is the sensor called "APS-C" size, when its output is in the wide-screen 1.89:1 shape of cinema 4K (4096x2160), not the 3:2 of "APS-C", and is likely instead to be something closer to Super 35mm format?

It is strange to describe a digital motion camera's format in terms of a failed still camera film format of different shape (3:2) when there is are well-established motion camera formats like Super 35mm that describe the situation better.

APS-C film format was 15.1x16.7, so 3:2. In fact the "C" refers to the "classic" 35mm film frame shape of 3:2.
It was always strange describing digital formats by using the name of a film format that hardly anyone ever knew and is anyway different (bigger).
On the other hand, Super 35mm has a well-established meaning for motion photography, both film and digital; in particular, the customers for such a camera know what Super 35mm means. So why not use motion camera format jargon when describing a motion camera?

Direct link | Posted on Apr 9, 2014 at 00:30 UTC
In reply to:

Joseph S Wisniewski: Wonder how many uFT lenses will cover the 25.3mm Super35 image circle.

Weird. If Panasonic hadn't recently dumped all their JVC Kenwood stock (they were JVC's largest single investor for half a century) I'd say "oh look, a Panasonic subsidiary has joined four thirds".

But right now, it makes no sense.

From the press release http://www.jvckenwood.co.jp/en/press/2014/04/press_140407.html

Proposal for new 4K-compatible camera system
1. [Reference Exhibit] 4K mini camera system
... This proposal will provide a new solution to expand the shooting field of the 4K camera system.

2. [Reference Exhibit] Interchangeable 4K compact handheld camera recorder
A “4K compact handheld camera recorder” will be on exhibit, featuring a 4K Super35mm image sensor, and MFT* Mount to flexibly accept a wide range of interchangeable lenses.

Item 2 makes me think that MFT mount is being used mostly as a "universal recipient", through which many lenses can be connected via adaptors.

But the Item 1 comment about "a new solution to expand the shooting field" intrigues me..

Direct link | Posted on Apr 8, 2014 at 23:44 UTC
On AJA enters cinema camera market with 4K Cion article (28 comments in total)

Why is the sensor called "APS-C" size, when its output is in the wide-screen 1.89:1 shape of cinema 4K (4096x2160), not the 3:2 of "APS-C", and is likely instead to be something closer to Super 35mm format?

It is strange to describe a digital motion camera's format in terms of a failed still camera film format of different shape (3:2) when there is are well-established motion camera formats like Super 35mm that describe the situation better.

Direct link | Posted on Apr 8, 2014 at 14:46 UTC as 8th comment | 5 replies

The 21x12mm mentioned in the article is a bit smaller than Super35mm, which is 24.9mm wide. So either that is a typo, or JVC is proposing a slightly smaller variant of 35mm cinema format (there are already plenty of variants around!). It is also only a 1.7mm larger image circle diameter than the 22.5mm diagonal of the official 18x13.5mm of official 4/3" format, even if current MFT sensors are a bit smaller than that.
Since many lenses cover a comfortably larger image circle that the format they are for (in particular, longer than normal lenses and zooms at all except their shortest focal lengths), I doubt that vignetting will be much of a problem. Also, mild vignetting in the corners of a video frame could be corrected with "lens correction" firmware.

Direct link | Posted on Apr 7, 2014 at 18:41 UTC as 31st comment | 2 replies

Does it come in Apple bayonet mount?

http://connect.dpreview.com/post/7100428395/apple-patents-bayonet-mount-for-mobile-devices

Direct link | Posted on Apr 3, 2014 at 17:27 UTC as 8th comment
In reply to:

razorfish: Why doesn't anyone have the guts to make a 17-120mm for a dslr or mirrorless? That would be a dream standard zoom, but everything starts at 24mm only so you still need to carry a true wideangle

This is for Super35mm movie camera format (frame width about 24mm) so its wide-angle coverage is comparable to 24mm with the 36x24mm frame of 35mm still camera format.
http://www.usa.canon.com/cusa/professional/products/lenses/cinema_lenses/cine_servo_lenses/cine_servo_17_120mm_t2_95_pl

Direct link | Posted on Apr 2, 2014 at 17:52 UTC
On Samsung announces tiny NX mini mirrorless camera article (80 comments in total)
In reply to:

Joe Ogiba: The smaller Panasonic GM1 has a larger sensor.
http://camerasize.com/compare/#545,491

"LxWxD" gives the volume of a box needed to store the camera with no lens attached; that does not strike me as a useful measure of portability.

Depth (front to back) with a lens attached is often the main constraint on fitting comfortably into a pocket or purse.

Direct link | Posted on Mar 19, 2014 at 18:01 UTC
On Samsung announces tiny NX mini mirrorless camera article (80 comments in total)
In reply to:

mpgxsvcd: How is this better than a Panasonic LX7? You get a brighter lens with a bigger zoom range for a lot less money. Sure it has a bigger sensor than the Panasonic. However, the Panasonic's lens is much brighter(More than 2 stops).

The LX7's combination of 1/1.7" sensor with a very bright f/1.4-2.3 zoom lens gives about the same DOF wide open as 1" format with f/2.4-3.9: shallower DOF than with either of the initial two NX-M lenses, the f/3.5 prime and f/3.5-5.6 "25-75mm equivalent" zoom.

Also:
- the lower f-stops of the LX7 allow use of lower ISO speeds by a factor of about 6, so it probably has better low light performance.
- the LX7 zoom range of 24-90mm equivalent goes a bit wider and longer that the NX-M zoom.

So interchangeable lenses (not many for now though!) and the "selfie-screen" are the main advantages of the NX-M.

Direct link | Posted on Mar 19, 2014 at 17:55 UTC
In reply to:

drawer77: i have a question about Red cameras for you gurus out there. i know the Red camera are modular cameras. But do they use a reflex system like a DSLR or are they mirrorless ?

Do you see an OVF on the body in the photo above?

REDs are purely video-out cameras, with very big, high-quality EVFs and external LCDs available to attach to the basic 'brain'".

Direct link | Posted on Mar 4, 2014 at 18:45 UTC
On Olympus OM-D E-M10 First Impressions Review preview (619 comments in total)
In reply to:

tjbates: Whichever way I look at it - the E-M10 looks like a marketing mistake in favour of the consumer. That doesn't happen very often.
The E-M10 is marketed as an entry level OM series camera - however on paper and I'm sure in reality - this camera looks to perform (purely in terms of image quality) as well as the E-M1. That's pretty special for a camera about half the price of it's bigger brother.

Olympus cameras follow the tradition of film cameras: cheap models get the same sensor/film as more expensive models in the same format, and are differentiated on other features of the body like weather sealing, higher frame rates, fancier AF systems, bigger and better viewfinders. I much prefer this to the Canon/Nikon/Sony approach where cheaper models in a given format often got inferior, older sensor designs.

BTW, Pentax does it right too: for example, the sensor that arrived in the K-5 was then used in all subsequent lower-priced Pentax DSLR bodies.

Direct link | Posted on Mar 2, 2014 at 15:24 UTC
On Olympus OM-D E-M10 First Impressions Review preview (619 comments in total)
In reply to:

bobbarber: Question:

If the output of this camera at ISO 200 is "not good", "unacceptable", "noisy", blah, blah, blah, as so many posters claim, and there are two stops difference between m43 and FF, does that mean that the output of Nikon FF cameras at ISO 800 is "not good", "unacceptable", and "noisy"?

There is no reason to expect smaller sensors to have a lower minimum usable exposure index ("ISO"), since that minimum is based on saturation of the photosites at highlights, and is mostly set by how many electrons the sensor can count _per_unit_area_ (along with the fraction if incoming photons that the sensor detects: QE). That measure is roughly 1500 to 2000 electrons per square micron regardless of sensor size, so the base-ISO speed does to vary much with sensor or photosite size: certainly not in direct proportion to sensor or photosite size.
This highlight-based lower limit (base ISO speed) is unrelated to the film-like "ISO speed", which is about signal-to-noise ratios and handling of low light levels, not highlight handling.

It is unfortunate that these different measures [(1) exposure level or EI (2) saturation-based lower limits on usable EI, (3) maximum EI or "ISO speed" based on noise] all get called "ISO" just because the same organization (The ISO) defines them all.

Direct link | Posted on Feb 28, 2014 at 16:53 UTC
On Phase One announces IQ250 50MP CMOS medium format back article (192 comments in total)
In reply to:

Anastigmat: I wonder if Canon and/or Nikon will shake up the market by making its own medium format CMOS sensors, cameras and lenses.

Almeida:
(1) Phase One management has said that the Sony sensor is available to all; no exclusivity. So I hope for a Pentax 645DII using it soon.

(2) One big barrier for Canon, Nikon or Sony offering a full system in a format larger than 35mm is developing a range of high quality lenses for what is always going to be a low volume market with vastly loess total revenues and profits than the 35mm and APS-C format DSLR markets. I doubt they see sufficient return on investment there, compared to investing in their 35mm and APS-C format systems.

After all, Canon and Nikon never bothered with MF film cameras (nor did Minolta or Konica or Olympus or ...), and that was a far larger and more profitable market than digital MF. (DMF has higher unit prices and profits, but only about one tenth the sales volume of MF film cameras, and about one hundredth the unit sales of 35mm format DSLRs.)

Direct link | Posted on Jan 27, 2014 at 21:23 UTC
In reply to:

James Pilcher: I'm a µ4/3 user and I'm glad to see the OMD E-M1 receving such recognition. The E-M5 received similar accolades last year. Having used 35mm film cameras since 1971 before switching to digital, I have to wonder why the giants Nikon and Canon are not better represented at the forefront of camera development right now. Are we awaiting an explosion of technology from Canikon, or is something amiss at those companies?

I am very happy with the innovations in Micro Four Thirds (and from Fujifilm X and Sony E), but since Canon and Nikon DSLRs still dominate system camera sales and profits, their apparent lack of innovation might simply mean that they will only have a profit motive to take mirrorless systems seriously when those newcomers bite deeper into DSLR sales.

In particular, Canon is probably in a good position to make EOS-M a more serious competitor, by adding an EVF, dual pixel PDAF, and a few more lenses. All of which might already exist in the R&D department.

Direct link | Posted on Jan 4, 2014 at 17:21 UTC
On Want to remember something? Don't take a photo article (183 comments in total)
In reply to:

neo_nights: One more thing: did anyone actually read the WHOLE study?

Anyone who has done an academic research knows how frustrating/infuriating it is to spend months/years reading, reasearching and such, write pages and more pages about something and then the press just publish a couple of lines about it, about its conclusion, and then everyone starts b*tching about it.

Be careful with pre-judgements, people.

Some commenters here do not even seem to have read the whole of the DPReview article; maybe they scanned the headline and jumped straight to the comments.

The second quote from the research paper indicates that the effect is likely to be only when people just take a quick snapshot and move on without otherwise paying attention to the subject, whereas looking at the subject carefully enough to compose a good photograph has the opposite effect.

In other words, some commenters here looked at the article in the the same way that some sloppy snapshooters look at the objects they are photographing; in either case, little is learnt.

Direct link | Posted on Dec 14, 2013 at 16:10 UTC
On Roger Cicala cynically re-defines photography article (54 comments in total)

He overlooked the classic
"Circle of Confusion: a bunch of photographers sitting around a table arguing about depth of field".

Direct link | Posted on Nov 26, 2013 at 00:06 UTC as 30th comment | 1 reply
On SD card labeling for 4K video announced article (50 comments in total)
In reply to:

scrup: Will the compact flash card die now! all it takes is for canon and Nikon to stop using this format. SD cards are getting faster and faster. all laptops have sd card slots.

The battle to replace CF is now between SD on one side and the two new rival "post-CF" high end formats, CFast and XQD on the other. The latter two offer higher speeds and capacities than CF or SD, and so might win some of the high-end video camera market, but I suspect that SD will continue its path to overall market dominance by becoming "good enough, supported by far more computers and cameras, and a lot cheaper".

Direct link | Posted on Nov 8, 2013 at 23:15 UTC
In reply to:

Archiver: Interesting how this is available only for the C100 at this time. If this can be implemented with the C300, it will show that dual pixel AF is a function of the CMOS sensor shared by the C100, C300 and C500, rather than the C100's hardware.

The C100 has four photodiodes for each output pixel: a 3840x2160 photosite array but maximum output resolution of 1920x1080 pixels, so it could easily have a single microlens over each 2x2 cluster of photodiodes, allowing it to use a pair of them for AF. Maybe
GG
RB
under each lens and feeding wach output pixel,
and using the GG pair for AF.

Direct link | Posted on Nov 8, 2013 at 02:29 UTC
Total: 216, showing: 21 – 40
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