fireplace33

fireplace33

Lives in Austria Upper Austria, Austria
Joined on Nov 28, 2007

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Total: 206, showing: 1 – 20
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Thanks for the inspiration :-)
Nice article.
Had some fun after reading this when I tried this myself and posted the results here if anyone wants to see.
https://www.dpreview.com/forums/thread/4204129

Link | Posted on Sep 17, 2017 at 17:08 UTC as 1st comment
In reply to:

fireplace33: Thought provoking article.
One thing I think some commenters seem to overlook is that at higher light intensities the noise is actually larger!
There isn’t a constant size of noise at all intensity levels, as I think some commenters are assuming.
Now we all know, after Richard’s many articles, that shot noise is the dominant noise source in an image (Poisson distribution), and the Standard deviation of that Shot noise coming from a light source is like sqrt(average number of photons arriving)
So, at higher light intensity levels, although the Signal to noise RATIO is much better, the ABSOLUTE number of digitised levels of noise is also GREATER vs. lower light levels
So at higher levels, a finer resolution of levels (more bit depth) will record the shot noise better, as Richard stated

e.g.
10 photons (S/N ratio is bad), something like +/-3 photons shot noise
10000 photons (S/N ration is much better) but something like +/-100 photons are shot noise
True or false? :-)

@ Arun H
Agree about read noise becoming more important at low levels

> "bottom line"
yes, for those reasons, for some time now I've been shooting with the "ETTR at lowest possible ISO" method to get the biggest signal and largest DR with lowest noise onto the sensor.
In PP I'll adjust and reduce the levels as necessary.

Link | Posted on Sep 3, 2017 at 13:11 UTC
In reply to:

fireplace33: Thought provoking article.
One thing I think some commenters seem to overlook is that at higher light intensities the noise is actually larger!
There isn’t a constant size of noise at all intensity levels, as I think some commenters are assuming.
Now we all know, after Richard’s many articles, that shot noise is the dominant noise source in an image (Poisson distribution), and the Standard deviation of that Shot noise coming from a light source is like sqrt(average number of photons arriving)
So, at higher light intensity levels, although the Signal to noise RATIO is much better, the ABSOLUTE number of digitised levels of noise is also GREATER vs. lower light levels
So at higher levels, a finer resolution of levels (more bit depth) will record the shot noise better, as Richard stated

e.g.
10 photons (S/N ratio is bad), something like +/-3 photons shot noise
10000 photons (S/N ration is much better) but something like +/-100 photons are shot noise
True or false? :-)

Agree !
.. a better S/N RATIO is good. And at high light levels it doesn't help much to differerentiate between 2 output values that are very close to each other since the absolute value of the noise is much bigger than these 2 adjacent bit values (at high light levels)

At the lower light levels you'll want those values to be close together to differentiate between them and get more DR but as we all know the noise starts to show it's ugly head when the light goes down. (because the S/N ratio is smaller at lower light levels)

Link | Posted on Sep 3, 2017 at 13:02 UTC

Thought provoking article.
One thing I think some commenters seem to overlook is that at higher light intensities the noise is actually larger!
There isn’t a constant size of noise at all intensity levels, as I think some commenters are assuming.
Now we all know, after Richard’s many articles, that shot noise is the dominant noise source in an image (Poisson distribution), and the Standard deviation of that Shot noise coming from a light source is like sqrt(average number of photons arriving)
So, at higher light intensity levels, although the Signal to noise RATIO is much better, the ABSOLUTE number of digitised levels of noise is also GREATER vs. lower light levels
So at higher levels, a finer resolution of levels (more bit depth) will record the shot noise better, as Richard stated

e.g.
10 photons (S/N ratio is bad), something like +/-3 photons shot noise
10000 photons (S/N ration is much better) but something like +/-100 photons are shot noise
True or false? :-)

Link | Posted on Sep 3, 2017 at 09:16 UTC as 31st comment | 4 replies

https://www.dpreview.com/forums/thread/4192047
This is a link to a post on the landscape forum where I just posted some waterfall shots from this weekend with similar equipment.
Oly Omd em5ii + 12-40 f2.8.
A great lens. And a nice lightweight system compared to my heavier Nikon gear.
The stabiliser on the oly is truely amazing! Surprisingly it allows for better handheld shots whem the light levels go down, despite the smaller sensor !

Link | Posted on Aug 14, 2017 at 09:44 UTC as 21st comment
On article Caltech research team develops lensless camera (61 comments in total)

Some time ago, I used to work as an ultrasound physicist developing machines for medical diagnostic imaging.
This idea reminds me of the phased arrays used in the ultrasound world to modify the focus of the ultrasound probe in both transmission and receive modes.
Very effective and superb ultrasound images produced, despite of course their own special set of limitations and artefacts.
Many here have probably even seen the very first photo of their children with this phased array technique!
… and I thought working at the speed of sound was difficult. Light is a whole new ball game 😉

Link | Posted on Jun 25, 2017 at 13:40 UTC as 4th comment
On article Surreal photo shows London high-rise fire from the air (16 comments in total)
In reply to:

steelhead3: Don't English buildings have sprinkler systems or was this neglected due to it being housing for the poor?

A news report mentioned that while most high rise buildings in the USA use "active" systems like sprinklers, British buildings more often use (less expensive) "passive" systems to contain a fire to a specific area and stop a fire from spreading.
--> Something that clearly did not work at all in this particular case!

Link | Posted on Jun 17, 2017 at 08:23 UTC
On article Before and after photos show Big Sur landslide (21 comments in total)

Very interesting article.
Amazing landslide photo. Well presented!

Link | Posted on May 28, 2017 at 15:45 UTC as 2nd comment
On photo tempête de neige in the Storms challenge (1 comment in total)

Nice shot !
I like the way the snow flakes make such bright streaks here.
Must have been quite windy!

Link | Posted on Mar 19, 2017 at 22:29 UTC as 1st comment
On photo Fresh and juicy in the fruit challenge (2 comments in total)

Great, would make a nice bright and bold series.

Link | Posted on Mar 12, 2017 at 21:07 UTC as 1st comment | 1 reply
In reply to:

Camera5: Guys, in future, please use logarithmic scales and make the use of colour more contrasty on your charts.

This cellphone comparison graph is making a valid point and making it very visually!!

Well done DPR!
I’m glad this particular chart was designed by DPR and not by Camera5 :-)
If it was presented in the more usual scientific , mathematical, “data design” way it would not provoke much attention at all.
... People would look at a “log plot” of this same info and forget it within seconds.
Presented in this long, long, long format, it stays in people's minds for much longer and shows just how big the cell phone market is.

Link | Posted on Mar 8, 2017 at 21:10 UTC
In reply to:

shademaster: you guys should look up "logarithm" ;)

@photomedium
yes, indeed ;-) like going to jail for 3 years for making a typo, then falling into a coma, & waking up three years later and walking free :-)

Link | Posted on Mar 7, 2017 at 20:48 UTC
In reply to:

falconeyes: For a much richer source of information, let me direct you to the joint presentation of CIPA and German GfK from 2017, February 24!

-> http://www.cipa.jp/stats/documents/common/cr1000.pdf (35 pages PDF)

Citation: "2016 is half of 2008 but still double size of film era."

@ Drogonrider
This cellphone comaprison graph is making a valid point and making it very visually!!

Well done DPR!

If it was presented in the more usual scientific , mathematical way it would not provoke much attention at all.
... People would look at a log plot of this same info and forget it within seconds.
Presented in this long, long, long format, it will stay in people's minds for much longer and show them just how big the cell phone market is in comaprison.

Link | Posted on Mar 7, 2017 at 19:09 UTC
In reply to:

shademaster: you guys should look up "logarithm" ;)

This cellphone comaprison graph is making a valid point and making it very visually!!

Well done DPR!

If it was presented in the more usual scientific , mathematical way it would not provoke much attention at all.
... People would look at a log plot of this same info and forget it within seconds.
Presented in this long, long, long format, it will stay in people's minds for much longer and show them just how big the cell phone market is in comaprison.

Link | Posted on Mar 7, 2017 at 19:05 UTC
On photo Sunset on the mud flats near Heide in the Mobile phone photography challenge (6 comments in total)

Thanks !
Nice to have a mobile phone with you when the conditions are looking good!
This was taken in the evening during a biz trip where I didn't have my normal bigger gear with me.
Quite pleased with the resulting image, and the win of course :-)

Link | Posted on Nov 28, 2016 at 09:29 UTC as 1st comment
In reply to:

lesnapanda: to charge a phone for full week in a couple seconds would require a charging current from a std 230V AC socket of around 185 amperes.

Ha!
Try putting that sort of current through a typical phone usb cable connector without frying it. :-)

Link | Posted on Nov 24, 2016 at 12:38 UTC
In reply to:

T3: Camera bags that force you to take them off and put them down in order to get your gear out of them kinda suck. Very impractical and cumbersome. I call these "never-ready" bags, because with your gear so out of reach and inaccessible, these camera bags mean you're never ready to shoot. These kinds of bags are fine for transporting all your stuff to a shoot location, at which time you put down the bag and set up shop, so to speak. But they are terrible for travel or street shooting where you really want to be able to access any piece of equipment at a moment's notice.

Very much agree!
the sling shot bag concept allows you to easily get to your gear and change lenses when you want, without having to stop and put the bag down somewhere; probably in the dirt and possibly out of sight.
I've been using and enjoying the sling shot bag for a few years now. Recently I had to go back to using a Rucksack, for a whole week, and this reminded me just how impractical any type of rucksack is for hiking while doing photography.
But each to their own,...

Link | Posted on Nov 6, 2016 at 11:57 UTC

"Barry Lyndon" is a great film. Watching it is like walking through a series of paintings from the old masters. Slow moving and quite long but intensely enjoyable.

Each set is carefully staged and beautifully shot. That Special lens certainly worked its magic in the low light scenes. Pure romance in the old traditional sense!
I'd definitely recommend it for photographers looking for some tips on composition.

Link | Posted on Jul 29, 2016 at 19:43 UTC as 22nd comment | 1 reply

Very impressive video!
Thanks , I enjoyed that

Link | Posted on Jul 13, 2016 at 18:48 UTC as 26th comment
In reply to:

fireplace33: A general question about tripods in carry on luggage,...
Is there ever an issue with such sharp metal spikes by the zelous secuity guards when checking in?

Fair enough,...I suppose a terrorist wouldn't think of screwing the removeable spikes back on once he's passed the security check ;-)

Link | Posted on Jul 9, 2016 at 12:41 UTC
Total: 206, showing: 1 – 20
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