ISO vs "Takes great low light photos"

[greenx]

I am under the presumption that ISO was always a camer's sensitivity to light in its contribution to exposure but does that necessarily always correlate with taking great night time photos? Reason why I bring this up is that I always tend to hear that the Sony a77 is great in low light conditions but noisy at higher ISO levels....

Thanks!

 

[o hey tyler]

I am under the presumption that ISO was always a camer's sensitivity to light in its contribution to exposure but does that necessarily always correlate with taking great night time photos? Reason why I bring this up is that I always tend to hear that the Sony a77 is great in low light conditions but noisy at higher ISO levels....

Thanks!

Are you asking if a camera with a larger ISO range will take better photos? Well, I've heard that the A77 gets pretty noisy at ~ISO1600.

I think the A77 is bad in low light due to the refresh rate of the electronic viewfinder. Go into a camera shop and use an A77. Pan the camera left to right and back again at a moderate pace. You'll see the viewfinder drag and be sluggish. Not a characteristic I'd want to deal with when there's less than favorable light.

 

[KmH]

The ISO range specification for a particular camera does not always mean the the entire range produces acceptable amounts of noise.

Note the image sensor ISO performance values from this independent testing lab that uses industry standard testing protocols:
DxOMark - Compare cameras side by side

You can also check independent camera reviews

Sony SLT-A77 In-depth Review: Digital Photography Review
Conclusion - Pros

• Excellent 2.4 million-dot OLED EVF
• Versatile full-time live view system
• Very high-resolution 24MP CMOS sensor (but see caveats in 'cons', below)
• Exceptionally 'deep' feature set including Auto HDR and Sweep Panorama
• Class-leading video resolution
• Solid, well thought-out ergonomics
• Fast and responsive operation
• Very good continuous shooting performance (particularly with UHS-I memory card)
• Efficient SteadyShot INSIDE image stabilization system
• In-camera GPS
• Good battery life

Conclusion - Cons

• In-camera JPEGs don't show off the 24MP sensor to its best extent
• Comparatively strong noise reduction at medium and high ISO settings
• Very noisy raw files at high ISO settings
• Little control over high ISO noise reduction in JPEG mode ('auto' or 'weak')
• Limited control in 12 fps continuous shooting and movie modes
• No live view in 8 or 12 fps continuous shooting modes makes accurate panning very difficult
• Menu system a little confusing (hard to orientate yourself sometimes)
• Slightly 'laggy' menu system and UI.
• Awkward to navigate between stills and movie playback mode

 

[greenx]

So is it fair to generalize poor high ISO settings equates to poor low light exposures/not the best camera for low light photography?

 

[unpopular]

aside from perhaps the a99, Sony has always struggled with low light/high ISO. There's some neat things about the SLT, especially for video and maybe high burst/action photography, provided that the newest batch of cameras have fixed the lag issue - but high ISO has never been Sony's strong point.

 

[Kolia]

So is it fair to generalize poor high ISO settings equates to poor low light exposures/not the best camera for low light photography?

No. The ISO rating refers to the old film sensitivity and is basically used in digital photography to signify how much signal amplification is being applied. Not all cameras will perform the same when shooting at a given ISO number. A camera labeled "better in low light" will have a better picture than an other one "less good" when using the same exposure settings.

 

[Kolia]

I think the A77 is bad in low light due to the refresh rate of the electronic viewfinder. Go into a camera shop and use an A77. Pan the camera left to right and back again at a moderate pace. You'll see the viewfinder drag and be sluggish. Not a characteristic I'd want to deal with when there's less than favorable light.

Total BS.

There is NO lag at all on the a65 and above (Using OLED EVF). You have either played with a defective camera or have not used one at all. Using both eyes, one looking through the EVF and the other unaided and there is no lag at all, regardless of light.

 

[Sw1tchFX]

So much for pushing my Tri-X...

 

[2fastlx]

I think the A77 is bad in low light due to the refresh rate of the electronic viewfinder. Go into a camera shop and use an A77. Pan the camera left to right and back again at a moderate pace. You'll see the viewfinder drag and be sluggish. Not a characteristic I'd want to deal with when there's less than favorable light.

Total BS.

There is NO lag at all on the a65 and above (Using OLED EVF). You have either played with a defective camera or have not used one at all. Using both eyes, one looking through the EVF and the other unaided and there is no lag at all, regardless of light.

I agree. I have both the a65 and a77 and there is practically no lag in the viewfinder. High iso performance is a different story though.

 

[unpopular]

So is it fair to generalize poor high ISO settings equates to poor low light exposures/not the best camera for low light photography?

No. The ISO rating refers to the old film sensitivity and is basically used in digital photography to signify how much signal amplification is being applied.

This is not true. As of 2006 the ISO has established standardization for digital cameras. The argument that it's "only roughly equivalent to film" is no longer accurate.

 

[KmH]

According to this, since 1998:

Film speed - Wikipedia, the free encyclopedia
The ISO 12232:2006 standard
The ISO standard ISO 12232:2006[SUP][55][/SUP] gives digital still camera manufacturers a choice of five different techniques for determining the exposure index rating at each sensitivity setting provided by a particular camera model. Three of the techniques in ISO 12232:2006 are carried over from the 1998 version of the standard, while two new techniques allowing for measurement of JPEG output files are introduced from CIPA DC-004.[SUP][56][/SUP] Depending on the technique selected, the exposure index rating can depend on the sensor sensitivity, the sensor noise, and the appearance of the resulting image. The standard specifies the measurement of light sensitivity of the entire digital camera system and not of individual components such as digital sensors, although Kodak has reported[SUP][57][/SUP] using a variation to characterize the sensitivity of two of their sensors in 2001.

 

[unpopular]

^^ in other words, for all intensive purposes it's always been a myth that camera ISO was based around rough equivalencies to film.

 

[o hey tyler]

I agree. I have both the a65 and a77 and there is practically no lag in the viewfinder. High iso performance is a different story though.

"Practically no lag" doesn't sounds like "no lag at all and is as clear as an optical viewfinder."

I rest my case.

And yes I've used one, thank you very much.

 

[thetrue]

So for Sonys, the viewfinder is electronic? How the hell do you focus in low light????

 

[Kolia]

I agree. I have both the a65 and a77 and there is practically no lag in the viewfinder. High iso performance is a different story though.

"Practically no lag" doesn't sounds like "no lag at all and is as clear as an optical viewfinder."

I rest my case.

And yes I've used one, thank you very much.

No lag at all