[Xastoul]

Hi all,



During the week I was able to take some nice picture here in washington Dc since I had some free time after working. For a stupid reason, I end up with my camera without my bag and I forgot to put back mmy lense cap. To make a Long sotry short, my filter have now a big scracht on it and it's unsable.



On my trip I saw a beautiful waterfall and I was trying to find a way to get a nice picture without my Nd filter. So I drop the ISO as low as possible (0.1). That make me wonder about the camera performance on lower than base ISO. Do really low ISO have the same effect than high iso?



Does it affect more the higlight?





Thank

[frank]

I think if the highlight is not cut off then low iso can get better image quality than base iso (with more shadow details).

[Xastoul]

[quote name='Frank' timestamp='1336616751' post='18085']

I think if the highlight is not cut off then low iso can get better image quality than base iso (with more shadow details).

[/quote]



In that case, it would be a better option to lower iso than using a filter, wright?

[frank]

[quote name='Xastoul' timestamp='1336617180' post='18086']

In that case, it would be a better option to lower iso than using a filter, wright?

[/quote]



I think so, if the low iso on your camara can give you the exposure that you want. It depends on the ability of your camera in lowering the iso. For example, the lowest ISO of D700 is 100, only one stop from the base iso 200. So, in general low iso cannot replace ND filters.

[Xastoul]

On my D5000 there is 3 setting lower than 200: low 03. ,low 0.7 and low 1. ( in that order)



I not sure why but the .7 setting is loer than .3... kind of strange. but the low 1 seem to give about 3 stop.

I'm happy that this was enough for what I was shooting.



But I see the limit of low iso.





thank

[frank]

[quote name='Xastoul' timestamp='1336622870' post='18089']

On my D5000 there is 3 setting lower than 200: low 03. ,low 0.7 and low 1. ( in that order)



I not sure why but the .7 setting is loer than .3... kind of strange. but the low 1 seem to give about 3 stop.

I'm happy that this was enough for what I was shooting.



But I see the limit of low iso.





thank

[/quote]



As far as I know low 1 corresponds to iso 100, low 0.7 and 0.3 correspond to values between 100 and 200: something like 125 and 175 respectively (I don't remember exactly). So, on D5000 the lowest iso is also 100, just 1 stop from the base iso 200 (low 1: 1 stop from 200; low 0.7: 2/3 stop from 200; 0.3: 1/3 stop from 200). If you are serious about long-time exposure in bright light, the low iso is definitely not enough.



In addition, usually low iso cannot be applied to a scene with high contrast since it tends to cut off the highlight.



Frank

[Xastoul]

[quote name='Frank' timestamp='1336623839' post='18090']

As far as I know low 1 corresponds to iso 100, low 0.7 and 0.3 correspond to values between 100 and 200: something like 125 and 175 respectively (I don't remember exactly). So, on D5000 the lowest iso is also 100, just 1 stop from the base iso 200 (low 1: 1 stop from 200; low 0.7: 2/3 stop from 200; 0.3: 1/3 stop from 200). If you are serious about long-time exposure in bright light, the low iso is definitely not enough.



In addition, usually low iso cannot be applied to a scene with high contrast since it tends to cut off the highlight.



Frank

[/quote]



Ok, that make more sense, I always taka care to not clip higlight . From what I understand , Those setting can allow me to "increase" the filter effect if the scen is suited for it.



Thank again for a new tip to increase my photography skill.

[Xastoul]

I would put my pic in but it seem I'm too dumb to upload it on here....





Edit:

anyways here a Link to it:

[url="http://forum.photozone.de/index.php?/gallery/image/943-first-waerfall/"]http://forum.photozo...first-waerfall/[/url]



but it seem somethin got wrong it the process when I put it into a "smal" Jpeg... ;(

[oppitronic]

I'll quote dpreview here:

The base sensitivity of the sensor used in the D5000 is ISO200. There is also a Lo 1.0 mode that attempts to mimic ISO 100 but it's effectively just ISO 200 over-exposed by a stop. The result is that the sensor becomes saturated and clips to white quite easily, limiting that mode's dynamic range. For most applications, you'd be better off buying a neutral density filter if you need slower shutter speeds than ISO 200 will allow.

(source: Nikon D5000 Review on dpreview.com http://www.dpreview.com/reviews/NikonD5000/18)



And my own experience matches that.

I only use Lo when I don't have my filter with me and want to take a wide open shot at bright sunlight and 1/4000s isn't fast enough.

[Xastoul]

[quote name='deroppi' timestamp='1336631960' post='18094']

I'll quote dpreview here:







(source: Nikon D5000 Review on dpreview.com [url="http://www.dpreview.com/reviews/NikonD5000/18"]http://www.dpreview....s/NikonD5000/18[/url])



And my own experience matches that.

I only use Lo when I don't have my filter with me and want to take a wide open shot at bright sunlight and 1/4000s isn't fast enough.

[/quote]



Interesting, Thank for the link!