NIKON > nastavenie ISO L1.0, - Digitálne zrkadlovky - Fórum | ePhoto.sk

maRmaRko 2011-06-17 15:02:25+02

Ahojte, mám takú otozočku.
Na mojej D90, ale aj na iných nikonoch (predpokladám) je takáto možnosť nastavenia ISO:
• L1.0 (100 equiv.)
• L0.7 (125 equiv.)
• L0.3 (160 equiv.)
• HI 0.3 (4000 equiv.)
• HI 0.7 (5000 equiv.)
• HI 1.0 (6400 equiv.)

Neviete ako to vlasne funguje? je to nejaké soft nastavenie foťáku? ale je to reálne iso ako ja napr. 200? (ako nemyslím to teraz že či je 6400 = 200

) Ale tak, že ak je to rálne iso 100 / 125 .... / 6400 Prečo je to potom značené ako L1 , H1.

nahlásiť nevhodný príspevok reagovať

0

Karol Srnec redakcia ephoto.sk

2011-06-17 15:14:19+02

Vcera vysvetloval Michael Jurak v BB. Cislami su znacene "prirodzene hodnoty" s ktorymi snimac pracuje. U oststnych bud dochadza k vyraznej zmene kvality, alebo je citlivost vyraznejsie ovplyvnena prevodnikom a softverom.

nahlásiť nevhodný príspevok reagovať

0

Karol Srnec redakcia ephoto.sk

2011-06-17 15:15:07+02

P.S. A vlastne je to aj tak suma fuk. Treba odskusat a pouzivat to, co sa ti zda dobre.

nahlásiť nevhodný príspevok reagovať

0

wikislav 2011-06-17 15:18:32+02

príspevok od: maRmaRko

Ahojte, mám takú otozočku.
Na mojej D90, ale aj na iných nikonoch (predpokladám) je takáto možnosť nastavenia ISO:
• L1.0 (100 equiv.)
• L0.7 (125 equiv.)
• L0.3 (160 equiv.)
• HI 0.3 (4000 equiv.)
• HI 0.7 (5000 equiv.)
• HI 1.0 (6400 equiv.)

Neviete ako to vlasne funguje? je to nejaké soft nastavenie foťáku? ale je to reálne iso ako ja napr. 200? (ako nemyslím to teraz že či je 6400 = 200

) Ale tak, že ak je to rálne iso 100 / 125 .... / 6400 Prečo je to potom značené ako L1 , H1.

Pridavam citat z http://www.flickr.com/groups/nikon_d300s_users/discuss/72157622290279947/

"The Hi and Lo ISO settings are digitally pushed at the ADC whereas the normal ISO settings are analougue gain settings on the amplifier. Light hitting the sensor fills the photosites of the sensor with photons which are charge accumulated, counted and turned around as a charge value. This is an analogue value. The amount of that value is determined by the sensitivity and gain. Like film, the sensor has a base sensitivity. For some sensors, it's 100 and others it may be 200. Any ISO value above that is the result of a gain setting on the amplifiers that increase the analougue signal level. This happens before the signal gets to the analougue-to-digital converter (ADC). At the ADC, the signal is quantised and digitally encoded. If a Hi or Lo ISO setting is used here something extra happens.

With a Lo setting, the sensor's amps are left at the lowest possible setting and the sensor is at its base/native ISO. The analougue signal is then fed to the ADC which then downgrades the signal levels when quantising them.

With a Hi ISO setting, the sensor is first boosted in gain up to its highest available analougue setting. The signal is then digitally quantised by upgrading (mapping) to a higher level.

The impact on DR and tone-curve when using Hi/Lo ISO settings is due to the digital conversion of remapping the analougue levels into a different quantisation value and thus this can cause either a compressed or extended tonal range from the original.

A somewhat analogous layman's way of thinking about the difference between regular ISO and Hi/Lo ISO settings is the comparison between optical zoom and digital zoom. As you know, an optical zoom does not produce pixelisation artifacts whereas digitally zooming (essentially cropping and magnifying) does."

nahlásiť nevhodný príspevok reagovať

0

maRmaRko 2011-06-17 15:19:14+02

príspevok od: Karol Srnec

P.S. A vlastne je to aj tak suma fuk. Treba odskusat a pouzivat to, co sa ti zda dobre.

Hej to je jasné vyskúšam

Nebol som v BB

Čiže vravíš, že relatívne môže byť na ISO L1 horší výsledok ako na ISO200?
Správne som to pochopil?

nahlásiť nevhodný príspevok reagovať

0

Marcel Rebro 2011-06-17 15:21:25+02

príspevok od: maRmaRko

Hej to je jasné vyskúšam

Nebol som v BB

Čiže vravíš, že relatívne môže byť na ISO L1 horší výsledok ako na ISO200?
Správne som to pochopil?

vyskusaj a uvidis ze ano

nahlásiť nevhodný príspevok reagovať

0

maRmaRko 2011-06-17 15:23:39+02

príspevok od: wikislav

Pridavam citat z http://www.flickr.com/groups/nikon_d300s_users/discuss/72157622290279947/

"The Hi and Lo ISO settings are digitally pushed at the ADC whereas the normal ISO settings are analougue gain settings on the amplifier. Light hitting the sensor fills the photosites of the sensor with photons which are charge accumulated, counted and turned around as a charge value. This is an analogue value. The amount of that value is determined by the sensitivity and gain. Like film, the sensor has a base sensitivity. For some sensors, it's 100 and others it may be 200. Any ISO value above that is the result of a gain setting on the amplifiers that increase the analougue signal level. This happens before the signal gets to the analougue-to-digital converter (ADC). At the ADC, the signal is quantised and digitally encoded. If a Hi or Lo ISO setting is used here something extra happens.

With a Lo setting, the sensor's amps are left at the lowest possible setting and the sensor is at its base/native ISO. The analougue signal is then fed to the ADC which then downgrades the signal levels when quantising them.

With a Hi ISO setting, the sensor is first boosted in gain up to its highest available analougue setting. The signal is then digitally quantised by upgrading (mapping) to a higher level.

The impact on DR and tone-curve when using Hi/Lo ISO settings is due to the digital conversion of remapping the analougue levels into a different quantisation value and thus this can cause either a compressed or extended tonal range from the original.

A somewhat analogous layman's way of thinking about the difference between regular ISO and Hi/Lo ISO settings is the comparison between optical zoom and digital zoom. As you know, an optical zoom does not produce pixelisation artifacts whereas digitally zooming (essentially cropping and magnifying) does."

Super dík, posledný odstavec je presne to vysvetlenie ktoré potrebujem

nahlásiť nevhodný príspevok reagovať

0

Karol Srnec redakcia ephoto.sk

2011-06-17 15:25:26+02

príspevok od: maRmaRko

Hej to je jasné vyskúšam

Nebol som v BB

Čiže vravíš, že relatívne môže byť na ISO L1 horší výsledok ako na ISO200?
Správne som to pochopil?

Pouzil som ISO 100 niekolkokrat a ziaden dramaticky pokles kvality som nevidel. Pouzivam bez vahania, napr. ked potrebujem predlzit cas. Inac pracujem vacsinou na ISO200.

nahlásiť nevhodný príspevok reagovať

0