dbm305

dbm305

Lives in Australia Sydney, Australia
Works as a Academic Philosopher
Has a website at www.dbm305.smugmug.com
Joined on Feb 24, 2008

Comments

Total: 14, showing: 1 – 14
On Zeiss announces Compact Zoom CZ.2 15-30mm T2.9 lens news story (62 comments in total)
In reply to:

dbm305: Hmm. What are the chances of ZE/ZF versions? a 15-30F2 right? It covers the full frame. And he hugely expensive 'compact' primes are the same optics as the ZE/ZF lenses....

F2.8? That makes T2.9 pretty impressive given how many elements there are in it (my guess was actually F2.5; F2 was a typo..)
Well the compact primes well for about five times the price of the same stills versions here, so that would make it $US5K if the same ratio held. So about the price of a relatively fancy Leica M rangefinder lens. I think some might pay.... Not me!

Direct link | Posted on Mar 28, 2014 at 08:17 UTC
On Zeiss announces Compact Zoom CZ.2 15-30mm T2.9 lens news story (62 comments in total)

Hmm. What are the chances of ZE/ZF versions? a 15-30F2 right? It covers the full frame. And he hugely expensive 'compact' primes are the same optics as the ZE/ZF lenses....

Direct link | Posted on Mar 28, 2014 at 02:45 UTC as 15th comment | 2 replies
On Sony Cyber-shot DSC-RX10 Review preview (423 comments in total)
In reply to:

Garth Wood: Maybe I've missed it somewhere in the review, but can anyone tell me definitively what the raw image bit-depth is? Discussion around the Intertubes seems to waver between 12-bit (which I expected) and 14-bit (a surprise), with at least one commenter claiming to have heard directly from Sony that it's 14-bit depth.

I own this little gem, and it's wonderful. But I don't have a solid idea of how much post-processing I can do before the image starts to break down or posterize; and the manual that came with the camera (and other official docs from Sony) is/are strangely silent on image bit-depth.

It'll be the usual Sony cRAW; it's very slightly lossily compressed, so it's hard to say what the bit depth really is: in practice it varies from area to area of the image. If I were to say average 12 that might be a bit meaningless, but maybe it helps. But it starts with 14 before compression. If you mess around with RAW digger or similar tools you might be directed to bits of the image at 100% where you can see the effects, but at the whole image level you get a smaller file size for no visible loss.

Direct link | Posted on Mar 20, 2014 at 23:16 UTC
On Sony plans March firmware update for Alpha 7 and 7R news story (120 comments in total)
In reply to:

dbm305: What does "support for fast AF mean"? Is it something separate from support for the new 70-200? Could it be a general AF speed upgrade, or perhaps enabling AF in the faster burst mode?

Perhaps then it's support for the focus limiting buttons. But are you sure? I know it was listed in the same line as mention of support for the 70-200, but it seemed pretty ambiguous to me and the translations are not that terrific!

Direct link | Posted on Mar 8, 2014 at 06:11 UTC
On Sony plans March firmware update for Alpha 7 and 7R news story (120 comments in total)

What does "support for fast AF mean"? Is it something separate from support for the new 70-200? Could it be a general AF speed upgrade, or perhaps enabling AF in the faster burst mode?

Direct link | Posted on Mar 8, 2014 at 04:17 UTC as 21st comment | 2 replies
On Sony Alpha 7R Review preview (759 comments in total)
In reply to:

moimoi: Shutter vibration that makes blurry images, have you forgotten dpreview?

It is a HUGE con.

Hmm. I suppose if the shutter speed needed to combat camera shake is also high enough to eliminate shutter shock, then that's a way of thinking that for practical purposes it's the same issue with the same fix...

Direct link | Posted on Feb 14, 2014 at 00:30 UTC
On Sony Alpha 7R Review preview (759 comments in total)
In reply to:

moimoi: Shutter vibration that makes blurry images, have you forgotten dpreview?

It is a HUGE con.

What Shawn says about shooting it like an MF camera is fair enough when it comes to camera shake; but shutter shock is another matter - it's a flaw. There are lots of potential ways of fixing it: electronic first curtain, a shutter that only goes to 1/4000 and which might not as much vibration. Maybe they couldn't do it yet, but it does count as a 'con', and a distinct con from the general fact that a very high res camera needs careful shooting. I'm still tempted though.

Direct link | Posted on Feb 13, 2014 at 22:03 UTC
In reply to:

highwave: It looks so good on the black OM-D

Both looks and spec wise, it's more fittingly the kit lens for the OM-D than the 12-50mm ever will be

E = MCsquared?

Direct link | Posted on May 21, 2012 at 08:11 UTC
In reply to:

topstuff: All very lovely, but this is'nt really an F2.8 lens is it, compared to APSC or FF?

What would be the equivalent APSC lens? A 17-50 I guess? And if my understanding is correct, would this 4/3 lens have to be a F1.4 to have the same light gathering as a F2.8 in larger sensors?

As said somewhere below, I don't think it is a simple as simply doubling the focal length to get a "FF equivalent" and keeping the max aperture the same.

I am not sure if this really a f2.8 as we know it. I am sure the people at DPR can clarify !

A lovely thing though I am sure, especially with an OMD EM5.

Of course the exposures will be identical. But the poster is still correct that four times the total light (not light per area) will be collected on an FF sensor in the larger image circle.

Of course that's what gives the better noise characteristics of the FF: total light.

So what needs to be disentangled are three things:

Depth of field: function of aperture, distance from subject, angle of view of lens and used image circle.

Total light: (and hence noise level): function of aperture, and used image circle (holding light levels and length of exposure fixed)

Exposure: function of aperture (holding light levels and length of exposure fixed).

Much of the discussion of these matters conflates the three.

Direct link | Posted on May 21, 2012 at 08:09 UTC
In reply to:

ZAnton: There is already Samyang 14mm f/2.8 for almost 1/10 the price.
Only real crazy techno-geeks will buy Zeiss.

Yes: which tells you something about Ken Rockwell!
The Samyang is cheap; yes. It has wild but correctible distortion, yes. But it's sharper than the N 14-24 or canon 14 2.8. Less CA. Better flare control than the N. It's not just me: read photozone or Lenstip.

Direct link | Posted on Mar 29, 2012 at 11:41 UTC
In reply to:

lucavascon: Aaaahhh... Zeiss!
It looks quite a deal if compared to 2nd hand 15mm f3.5 in Contax mount!!!
However I do prefer old Contax mount primes adapted to 5D. And new ones still have better taste than Nikon and Canon primes (specially Canon primes, that are disappointing me so much).
For those who do not appreciate the difference between the Zeiss and other lenses, if you don't see it, it means your way, taste, and preferred light condition in taking pictures is not putting your lens in crisis. No "absolute"better in lenses and tools There is simply a tool that "fits better" in your hand for that situation

@ZAnton, I tried the Samyang 14, quite unusable for me. Far prefer using the good 15mm fisheye Sigma and than correct it with PanoTools

@thx1138, you got the point. I do not like zooms, I usually prefer zeiss and do not use filters (although sometimes, I'd like a polarizing one). But I've tried that 14-24 and I can only say that it is a fantastic, German-feeling ultrawide, I'd go for it.

What problem do you have with the Samyang? It has crazy distortion, but one of the good things about it's distortion pattern is that when you correct it with a LR profile you don't lose much angle of view. And it has extremely
high resolution.

Direct link | Posted on Mar 29, 2012 at 11:39 UTC
On Canon EOS 5D Mark III studio samples published news story (287 comments in total)

Oh well. I haven't downloaded and normalized the D800 RAW pics yet, but based on how they look (only slightly worse than the 5dIII at 1:1) I'm guessing it'll come out the same or slightly better normalised. And all those nice pixels. Still, I don't regret my 5D III: it's handily better than the II (2/3 stop in RAW? That's really pretty useful = especially if it cleans up better which is my experience so far) and it would take me three years to get as proficient with the Nikon interface, by which time who knows who'll have the nicest sensor? And I do love my 17mm TSE....

Direct link | Posted on Mar 28, 2012 at 13:33 UTC as 97th comment
On Canon EOS 5D Mark III studio samples published news story (287 comments in total)

Um, they don't seem to be up yet....

Direct link | Posted on Mar 28, 2012 at 13:07 UTC as 108th comment
On First Impressions: Using the Canon PowerShot S100 article (191 comments in total)
In reply to:

ET2: "Sometimes reviews get delayed."

No kidding. The preview (forget the review) of Nex-7 was promised back 3 months ago?

The first S90 I got was just frighteningly decentred; the whole right side was smeared and the right hand corners were just a blur. I sent it back to Adorama (I think) and got another that was still noticeably decentred - soft in lower right at all apertures, but not so much that it was too much of a pain in normal shooting.

Direct link | Posted on Dec 8, 2011 at 07:10 UTC
Total: 14, showing: 1 – 14