ISO Expansion - ISO 50, Good or Bad?

[Waddizzle]

I am fairly new to DSLRs, with just over 2 years under my belt, but not SLR photography.  I am still learning all of the nuances that digital photography brings to the table, compared to my film world from 30 years ago.  Let's say I took a sabbatical from the hobby, so I could raise a couple of sons.  The drug store disposables were more economical than using an SLR.

Enough of that.  I have recently rediscovered that my 6D has ISO expansion at the top end, like most Canon DSLRs.  But, it also has an expansion in the low, "L", direction, too.  The higher ISOs tend to introduce noise, and freely admit that I have never used them. 

However, I recall going through the menus early on, and making a decision not to make ISO 50 available for use.  I have run into several occasions where a wide open aperture [f/1.4], ISO 100, and a 1/4000 shutter speed, added up to an overexposure.  I found that I either had to stop down the aperture, which upset the bokeh I wanted, or resort to using an ND filter, which frequently introduce their own set of WB and CA problems.

I do not recall the rationale behind my decision to make ISO 50 unavailable for use.  Does the ISO 50 setting put extrain strain on the sensor or electronics?  At the moment, I cannot think of how it could be harmful.  Obviously, there is some drawback associated with it.  Otherwise, why would it be made an option, like high ISO expansion, instead of simply making it available at all times?

[ebiggs1]

Peter 

Yes sir I think we got on the same page!

"...  to show how much greater Sony is (than Canon) ..."  

I don't think this is even a point of contention any more.  Probably why Nikon started using sensors made by Sony for a lot of their cameras.  But I think I read they went back to a Nikon designed sensor made by some other company, not Sony, for the D4 and D4s.  Maybe even the D5.

[Peter]

With all this said I don't know the behaviour of the new 1DxII or 80D.

[ebiggs1]

Neither do I but I am not interested in a 80D.  However I can see a 1Dx or 1Dx Mk II gracing my formerly stop bath stained hands.  So we might just have to see!

[RobertTheFat]

---

@ebiggs1 wrote:

Neither do I but I am not interested in a 80D.  However I can see a 1Dx or 1Dx Mk II gracing my formerly stop bath stained hands.  So we might just have to see!

---

Ernie, despite your earlier disclaimers, it's perfectly clear that you've been bitten by the 1DX bug. There is no known antidote other than aquisition of the device itself; the alternative is to scratch the resulting itch indefinitely. You can keep up the charade for as long as you please, but you're only torturing yourself by doing so. The 1DX2 has already been announced, and the waiting list grows with the passage of time.

[ebiggs1]

Bob from Boston,

 I am guilty as charged.