BorisK1

BorisK1

Lives in United States West Bloomfield, MI, United States
Works as a Software engineer
Joined on May 7, 2004
About me:

Equipment:
Bodies: Olympus E-3, E300
Lenses: 11-22mm / 50mm / 14-45mm / 40-150mm (rev. I)
FL-36 flash
4:3/OM adapter
OM bodies: OM 4Ti, OM 4
OM lenses: 28mm 3.5 / 50mm 1.8 / 135mm 3.5
T32 flash
Pentax Optio 43wr (pretty much dead now)

Comments

Total: 191, showing: 21 – 40
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On Medium well done: Two takes on the Pentax 645Z article (245 comments in total)
In reply to:

sportyaccordy: For whatever its worth, in the studio comparison anyway, the D810 gives nothing up to the 645Z on a 100% view basis as far as noise goes. Def want to see its DR capabilities as well as ability to pull info from dark/underexposed areas. DxOMark's data can't come soon enough. Not in the market, just want to see what it can do.

"Um, I thought transistors step discretely, unlike vacuum tubes"
No, that is not the case. A transistor can be fully "open" or fully "closed", but gradually increasing the driving voltage causes its resistance to decrease in a smooth curve, not as an abrupt tradition.

If not for this smooth response curve, it would have been impossible to use transistors in amplifiers.

You should be able to confirm this with a quick Google search, or a wiki article.

Direct link | Posted on Dec 11, 2014 at 03:50 UTC
On Medium well done: Two takes on the Pentax 645Z article (245 comments in total)
In reply to:

sportyaccordy: For whatever its worth, in the studio comparison anyway, the D810 gives nothing up to the 645Z on a 100% view basis as far as noise goes. Def want to see its DR capabilities as well as ability to pull info from dark/underexposed areas. DxOMark's data can't come soon enough. Not in the market, just want to see what it can do.

Transistors are the basic building blocks of electronics. One can use transistors to build both analog circuits (like amplifiers) and digital circuits (like logic gates). But a transistor, by itself, is analog, and its response is a smooth curve.

Direct link | Posted on Dec 11, 2014 at 01:02 UTC
On Medium well done: Two takes on the Pentax 645Z article (245 comments in total)
In reply to:

sportyaccordy: For whatever its worth, in the studio comparison anyway, the D810 gives nothing up to the 645Z on a 100% view basis as far as noise goes. Def want to see its DR capabilities as well as ability to pull info from dark/underexposed areas. DxOMark's data can't come soon enough. Not in the market, just want to see what it can do.

HowaboutRAW:
> "The photo receptors on sensors are transistors"
No, photodetectors are not transistors. The two are fundamentally different. Photodetectors generate electricity when hit by photons. Transistors change resistance when hit by electrons.
Photodetectors have linear responses, transistors don't (look at their response curves in Google images).

However, both photodetectors and transistors are analog devices. Their response curves are smooth, not stepped.

Direct link | Posted on Dec 10, 2014 at 21:44 UTC
On Medium well done: Two takes on the Pentax 645Z article (245 comments in total)
In reply to:

sportyaccordy: For whatever its worth, in the studio comparison anyway, the D810 gives nothing up to the 645Z on a 100% view basis as far as noise goes. Def want to see its DR capabilities as well as ability to pull info from dark/underexposed areas. DxOMark's data can't come soon enough. Not in the market, just want to see what it can do.

falconeyes:
You put my name on top of HowaboutRAW's text. Why?

Direct link | Posted on Dec 10, 2014 at 19:45 UTC
On Medium well done: Two takes on the Pentax 645Z article (245 comments in total)
In reply to:

sportyaccordy: For whatever its worth, in the studio comparison anyway, the D810 gives nothing up to the 645Z on a 100% view basis as far as noise goes. Def want to see its DR capabilities as well as ability to pull info from dark/underexposed areas. DxOMark's data can't come soon enough. Not in the market, just want to see what it can do.

HowaboutRAW:
Sorry, I mistyped, I meant ADC, not DAC.

Yes, photons hitting a sensor are discrete events, but sensors *function* as analog devices. There is no counter that would get incremented every time a photon hits it. There's no way to walk through each atom within a sensor element and total up their electrons' energy levels.

Just as they did when were first invented, sensor elements accumulate electric charge, which is then transferred to the edge of the chip, amplified, and then measured by an ADC converter. That charge is proportional to the number of photons that hit the sensor, but there's no way ADC could measure it with enough precision to count individual electrons.

Sure, a sensor is not a solar sell - but an individual sensing element is very similar to one.

"All raws are cooked a bit by the processor" - I must have missed the day this became common knowledge. Could you post a link?

Direct link | Posted on Dec 10, 2014 at 17:21 UTC
On Medium well done: Two takes on the Pentax 645Z article (245 comments in total)
In reply to:

sportyaccordy: For whatever its worth, in the studio comparison anyway, the D810 gives nothing up to the 645Z on a 100% view basis as far as noise goes. Def want to see its DR capabilities as well as ability to pull info from dark/underexposed areas. DxOMark's data can't come soon enough. Not in the market, just want to see what it can do.

HowaboutRAW: The only way a processor could affect raw DR is by being "quiet" electrically and cold (meaning literally, temperature-wise) while the image data is being captured and DAC-converted.
Well, unless we consider "cooked RAW" - with some NR applied before JPEG conversion - but I thought FF cameras didn't do that, as a rule?

Direct link | Posted on Dec 10, 2014 at 16:18 UTC
On Medium well done: Two takes on the Pentax 645Z article (245 comments in total)
In reply to:

sportyaccordy: For whatever its worth, in the studio comparison anyway, the D810 gives nothing up to the 645Z on a 100% view basis as far as noise goes. Def want to see its DR capabilities as well as ability to pull info from dark/underexposed areas. DxOMark's data can't come soon enough. Not in the market, just want to see what it can do.

falconeyes:
Aside from CMOS vs CCD differences, there's the matter of electromagnetic noise. Nikon is very good at keeping the camera "quiet" electrically. There were DSLRs (sorry, don't remember which off the top of my head) where Nikon managed to get a stop more DR than Sony - using the same sensor.
To sportyaccordy - I think, the formula is just falconeyes way of saying "DR goes up with sensor area and goes down with ISO". It's a very rough estimate that only works (kind of) because the sensors' base ISO doesn't change very much (unless you want to mention that Kodak DSC 14n that had ISO of 6 :) ).

Direct link | Posted on Dec 10, 2014 at 15:48 UTC
On Medium well done: Two takes on the Pentax 645Z article (245 comments in total)
In reply to:

sportyaccordy: For whatever its worth, in the studio comparison anyway, the D810 gives nothing up to the 645Z on a 100% view basis as far as noise goes. Def want to see its DR capabilities as well as ability to pull info from dark/underexposed areas. DxOMark's data can't come soon enough. Not in the market, just want to see what it can do.

"What is the denominator in this formula" - I assumed, base ISO.

Direct link | Posted on Dec 9, 2014 at 19:09 UTC
On Medium well done: Two takes on the Pentax 645Z article (245 comments in total)
In reply to:

Jogger: Things will get interesting once the next generation of high resolution Sony FF sensors come online. Scaling a 24mp APSc up would give you about 54mp.

"There are dynamic range advantages to bigger pixels"

For the reference:

D810 pixel width = 0.04891mm
645Z pixel width = 0.05329mm
D750 pixel width = 0.05984mm

Direct link | Posted on Dec 9, 2014 at 18:54 UTC
On Medium well done: Two takes on the Pentax 645Z article (245 comments in total)
In reply to:

sportyaccordy: For whatever its worth, in the studio comparison anyway, the D810 gives nothing up to the 645Z on a 100% view basis as far as noise goes. Def want to see its DR capabilities as well as ability to pull info from dark/underexposed areas. DxOMark's data can't come soon enough. Not in the market, just want to see what it can do.

falconeyes:
According to your formula, 645D's DR should've been the same (33x44 / 100 = 14.5). And yet, DxO measured it at 12.55:
http://www.dxomark.com/Cameras/Pentax/645D---Measurements
What leads you to expect two stops DR improvement in 645Z?

Direct link | Posted on Dec 9, 2014 at 18:33 UTC
On Medium well done: Two takes on the Pentax 645Z article (245 comments in total)
In reply to:

sportyaccordy: For whatever its worth, in the studio comparison anyway, the D810 gives nothing up to the 645Z on a 100% view basis as far as noise goes. Def want to see its DR capabilities as well as ability to pull info from dark/underexposed areas. DxOMark's data can't come soon enough. Not in the market, just want to see what it can do.

The Davinator: I agree. Fast lenses are more needed for low light and shallow DOF scenarios.
badi: Agreed as well. If you have to get those 50Mpix in a single shot, your options are limited.

Direct link | Posted on Dec 9, 2014 at 15:25 UTC
On Medium well done: Two takes on the Pentax 645Z article (245 comments in total)
In reply to:

sportyaccordy: For whatever its worth, in the studio comparison anyway, the D810 gives nothing up to the 645Z on a 100% view basis as far as noise goes. Def want to see its DR capabilities as well as ability to pull info from dark/underexposed areas. DxOMark's data can't come soon enough. Not in the market, just want to see what it can do.

Chances are, Pentax DR will be behind the D810 by at least a stop. Resolution is the *only* advantage you get.
What you lose though, is the fast lenses. I don't think there are any modern Pentax lenses faster than f:2.8 (equivalent to f:2.24 on FF).

Direct link | Posted on Dec 9, 2014 at 15:01 UTC
In reply to:

fmian: Hopefully they will fix the shutter shock issues.
Otherwise what good are 40mp photos if they are blurry?

Electronic shutter fixed that problem a while ago.

Direct link | Posted on Dec 5, 2014 at 02:08 UTC

So, is this just for backup/storage, or for photo hosting too?

If I have pictures stored on Amazon Cloud drive, can it create a gallery visible to somebody who is not logged in?

Direct link | Posted on Nov 4, 2014 at 19:59 UTC as 38th comment
On Panasonic Lumix DMC-LX100 First Impressions Review preview (1864 comments in total)

To all you complaining about noise in ISO 200 shot (the Seattle view):

On a bright sunny day, the "sunny-16" rule says that for F/8, ISO200 the exposure needs to be 1/400 or thereabout.

This is sunset, so it's a couple of stops darker. Proper exposure should be at least 1/100, probably longer.

The shot used 1/3200. That's FOUR TO FIVE STOPS under (at least).

FIVE STOPS!

Then it's pushed up 4 stops in postprocessing.

The comment says it's done "to protect highlights".

Direct link | Posted on Oct 30, 2014 at 15:07 UTC as 52nd comment
In reply to:

Menneisyys: Regarding the new uploads,

3040827 – In the new images too, shadow noise is rather high even in base ISO - see the white/gray rocks' surface in the lower right corner. This camera in no way can match the noiseless-ness of full frame or Fuji crop cameras at base ISO.

3040823 – in sweep panos,

1, exposure changes could be a little bit less obtrusive (see the subtle exposure change steps in the sky) and
2, more vertical pixels used (I assume this camera also shoots at either 1920 or 1080 pixels high panoramas, just like Sony's cameras).

These may mean you still won't want to stop shooting individual images and stitch them on the desktop.

3040827 is coping with extreme contrast. Background is in bright sunlight, the subject is in deep shadow. The face is *massively* underexposed and then pushed up several stops.

It's Panasonic's "Intelligent exposure" DR expansion at work.

Direct link | Posted on Oct 6, 2014 at 14:11 UTC
On Leica T (Typ 701) First Impressions Review preview (2242 comments in total)
In reply to:

stevens37y: "solid block of aluminum"
They should use titanium. Looks and feels much better.

But with enriched uranium, you'd get a much brighter flash!

Direct link | Posted on Jul 23, 2014 at 15:32 UTC
On Leica T (Typ 701) First Impressions Review preview (2242 comments in total)
In reply to:

stevens37y: "solid block of aluminum"
They should use titanium. Looks and feels much better.

A camera made from same material as *bicycles*? That's so pedestrian!
(badabum)

Direct link | Posted on Jul 23, 2014 at 13:44 UTC
On Leica T (Typ 701) First Impressions Review preview (2242 comments in total)
In reply to:

cgarrard: I wonder if Leica will consider make matching toilet paper for this camera?

C

Matching? As in, machined from solid aluminum? Yikes!

Direct link | Posted on Jul 23, 2014 at 13:32 UTC
On Leica T (Typ 701) First Impressions Review preview (2242 comments in total)
In reply to:

groucher: Should be a good caver's camera - a bit of grit, mud, water, bashed around in a tackle bag. Don't like the silly touch screen though - will it work with muddy hands?

From the manual:
"If you intended to take a shot and discovered that your hands were muddy, ask the enclosed butler to wipe them for you with dry, clean cloth."

Direct link | Posted on Jul 23, 2014 at 13:29 UTC
Total: 191, showing: 21 – 40
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