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Why ISO 200?

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Is there an insurmountable reason why  Fuji X's lowest ISO is 200?   ISO 50 would much appreciated on certain occasions:  moving clouds, flowing water, etc.  Yes, I can (and do) use ND filters (note the plural) but needed two full stops of ND filtration just to slow the shutter down to what I used to start with Koda/Ekta-Chrome is annoying at times.  

 

(PS- if this topic was covered else where I appologize  --   please advise -- I looked unsuccessfully)

Edited by MSW

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This may help. A bit tedious but you may get a clearer picture.

 

"It is supposed to be the sensitivity where the sensor gives its “best” performance, as determined by dynamic range (large) and noise (minimal)"

 

http://dpanswers.com/content/tech_iso.php

 

If the base ISO is 200, there will be little benefit going below that although some cameras do have a selection for "pseudo" ISO50 or 100.

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Seven Fuji X models use ISO 100 as their base: X10, X20, X30, X-S1, XF1, XQ1, XQ2. That's because they use a different sensor type that has a different base sensitivity.

 

IIRC, cameras such as the Arri Alexa use base ISO 800, and the Leica Monochrom uses base ISO 320.

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I don't know how a simulated ISO 50 is implemented but I certainly wouldn't mind having that option on bright summer days.

 

 

Actually, simulated ISO is more useful on dull days with little DR. On bright days, they do not change a thing. Btw, all Fuji models with base ISO 200 offer simulated ISO 100. The X-Pro2 also saves ISO 100 RAWs. Doesn't help at all on bright days, as highlight DR drops 1 stop.

 

Btw, my books describe how it is implemented.

Edited by flysurfer

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The sensor itself has only one ISO which is the base ISO.
Some cameras adjust the analog amplification when the electrical charge is transferred from the sensor to the analog to digital converter. But most part of ISO adjustment is done by over or under exposure and compensation when the JPEGs are created. It does not matter if they are created internally or by a RAW converter.
I remember that Rico/flysurfer wrote about ISOless sensors some time ago.

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I've always heard that Fuji is using a different ISO standard than Nikon/Canon. Basically their ISO 200 is about the same as Nikon/Canon ISO 100, which means you will get about the same exposure. It's the same reason you can't compare Nikon 6400 ISO with Fuji 6400 ISO... it's more fair to compare with Fuji 12800 ISO.

 

Maybe someone can confirm what I'm saying..

Edited by sebas1430

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I've always heard that Fuji is using a different ISO standard than Nikon/Canon. Basically their ISO 200 is about the same as Nikon/Canon ISO 100, which means you will get about the same exposure. It's the same reason you can't compare Nikon 6400 ISO with Fuji 6400 ISO... it's more fair to compare with Fuji 3200 ISO.

 

Maybe someone can confirm what I'm saying..

 

Oh certainly, first of all Fuji is not even using the same ISO standard as Canikon, as you said it yourself. I forgot all the technicalities of it but, they do have different ISO behavior while at the same ISO numerical value.

That started the whole "Fuji Cheats their ISO" thingy a couple of years ago and we are still seeing that comment pops up every one in a while. Long story short, there is about 2/3 stops worth of differences between Fuji ISO standard and Canikon's.

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This is also what I do not understand, why RAWs are not posible when using the extended ISO settings. When someone pushes the sensor to its limits then RAW would deliver the best starting material for the processing steps.

 

Yes, you can over oder under expose to get the same result, but the EVF does not give a proper preview of the exposure.

 

Obviously Fuji came to the same conclusion when they designed the X-Pro2.

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This is also what I do not understand, why RAWs are not posible when using the extended ISO settings. When someone pushes the sensor to its limits then RAW would deliver the best starting material for the processing steps.

 

Yes, you can over oder under expose to get the same result, but the EVF does not give a proper preview of the exposure.

 

Obviously Fuji came to the same conclusion when they designed the X-Pro2.

 

 

They are possible and users asked for them, so Fuji put them in the Pro2 (and probably all future models, too).

 

Of course, you can always produce an ISO 100 RAW by simply overexposing one stop at ISO 200, then pull the data –1 EV in the built-in RAW or an external converter. That's exactly what the camera does before writing the ISO 100 RAW file.

 

It's the same with extended high-ISO. EXR I/II cameras stopped at ISO 1600 and left all higher values to the RAW converter. X-Processor III burns everything up to ISO 25600 in the RAW file, so only ISO 51200 requires an additional 1 stop push during RAW conversion. As usual, Adobe took this single opportunity to mess things up in Lightroom, so imported ISO 51200 RAWs will look like ISO 25600 RAWs, because Adobe forgot the push. They also messed up other things like DR-Auto maker notes, once again providing proof that they don't give a shit about users of Fujifilm cameras.

Edited by flysurfer

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Is there an insurmountable reason why  Fuji X's lowest ISO is 200?   ISO 50 would much appreciated on certain occasions:  moving clouds, flowing water, etc.  Yes, I can (and do) use ND filters (note the plural) but needed two full stops of ND filtration just to slow the shutter down to what I used to start with Koda/Ekta-Chrome is annoying at times.  

 

(PS- if this topic was covered else where I appologize  --   please advise -- I looked unsuccessfully)

It's a double edged sword don't forget... If it started at ISO 50 it would have less quality at ISO6400, in fact ISO1600 would look like existent ISO6400! Scary thought :)

 

Max DR is base ISO. So base ISO gives you the most room in the highlights and shadows, and maximum details

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Oh certainly, first of all Fuji is not even using the same ISO standard as Canikon, as you said it yourself. I forgot all the technicalities of it but, they do have different ISO behavior while at the same ISO numerical value.

That started the whole "Fuji Cheats their ISO" thingy a couple of years ago and we are still seeing that comment pops up every one in a while. Long story short, there is about 2/3 stops worth of differences between Fuji ISO standard and Canikon's.

Celsius / Fahrenheit :)

 

Hey, you just helped the OP, Fuji base ISO is now about 160 :) :) :)

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They are possible and users asked for them, so Fuji put them in the Pro2 (and probably all future models, too).

 

Of course, you can always produce an ISO 100 RAW by simply overexposing one stop at ISO 200, then pull the data –1 EV in the built-in RAW or an external converter. That's exactly what the camera does before writing the ISO 100 RAW file.

 

It's the same with extended high-ISO. EXR I/II cameras stopped at ISO 1600 and left all higher values to the RAW converter. X-Processor III burns everything up to ISO 25600 in the RAW file, so only ISO 51200 requires an additional 1 stop push during RAW conversion. As usual, Adobe took this single opportunity to mess things up in Lightroom, so imported ISO 51200 RAWs will look like ISO 25600 RAWs, because Adobe forgot the push. They also messed up other things like DR-Auto maker notes, once again providing proof that they don't give a shit about users of Fujifilm cameras.

Am I right in thinking that X-Trans I/II used analogue ISO push up too 1600 then digital gain up to 6400 (on raw)?

 

Thanks

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Am I right in thinking that X-Trans I/II used analogue ISO push up too 1600 then digital gain up to 6400 (on raw)?

 

Thanks

 

Somewhat analog, somewhat digital up to 1600, from there only in the RAW converter. 

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I've always heard that Fuji is using a different ISO standard than Nikon/Canon. Basically their ISO 200 is about the same as Nikon/Canon ISO 100, which means you will get about the same exposure. It's the same reason you can't compare Nikon 6400 ISO with Fuji 6400 ISO... it's more fair to compare with Fuji 12800 ISO.

 

Maybe someone can confirm what I'm saying..

 

I recently tested my Fuji X-T10 against a Canon 5D Mark III and a free lightmeter app, and it seemed more like the Fuji's ISO was only 1/3 stop darker.

Edited by MarkHaertl

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Ah back in the good ole days I remember by Fuji Finepix S1Pro dSLR with the two different batteries, had a MINIMUM ISO of 320!!  Those 3 megapixel files were fabulous!  ISO 800 was about the max unless you had some serious noise reduction skills as LR wasn't around.  I remember using Noise Ninja back then.  

 

Ahhhh.  The good ole days (insert sarcasm here)

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Go back in time. Get some low speed films. ORWO NP 10. Expose at 50 % and develop half time. Make a scan.

Or put some welding safety glass in front of your Fujinon. Or sandwich two Pola filter together; rotate the filter and block the light

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