Nikon D80 - What is Gain Control

[Brownbear]

I'm still trying to figure out what "Gain Control" is on my Nikon D80...

On some of my camera specs it will say none and sometimes it says "Gain Up". I've goggled it, looked at my camera manual (D100 manual) and on my camera for such a button but I can't find any useful information on the subject.

I just want to know what it is for and why the settings change in my camera, even though I have never adjusted the setting, nor can I find a button or dial on my camera for this mysterious feature.

Thank you.

[blakemcguire]

I could be completely wrong, but IIRC, gain is effectively a tone curve applied to the raw conversion, which affects how bright your highlights and how dark your shadows are.

But I'm going off of foggy memory on this.

[Brownbear]

Thank you.

It could be... Sometimes I change the tone compensation curve in the custom settings which would explain why I see sometimes see it on, low gain control could be less contrast in the curve and high gain control could be a higher contrast curve?

[Manfred M]

"Gain" is engineering speak for amplification. If someone refers to "increasing gain", it means turning up the level of amplification, and of course the opposite is true for "decreasing gain", it means turning down the level of amplification. On a digital camera, selecting a higher ISO setting means you are increasing gain.

[Brownbear]

Thank you Manfred.. Are you sure?

If yes, why is it that not all my photo specs say gain control... some say none, some say high, and some say low... I don' recall ever increasing a button that says increase gain control... Of course I often increase my iso, but it seems odd that my camera specs would have a reading to tell me I did this? And if this is the case, what is the point of doing so?

Maybe it is a result of setting my camera to iso auto, say 800 max?

Thank you.

[Mike Buckley]

The only references to "gain" in the D80 User Manual have to do with:

Multiple Exposures -- pages 84 & 85
Image Overlay (making one RAW file from two RAW files) - page 114

So, consider Manfred's and Blake's explanations in the context of using the camera to create one image from multiple images. Perhaps they can expand on the concept of "gain" in that context.

I have been using D80s for years and have never used any setting that configures the gain.

[Brownbear]

Thank you Mike... I've never done a multiple exposure or combined raw images, but I see this spec quite a bit.

[Mike Buckley]

It could be helpful to make a note every time you come upon the configuration. Even though the manual refers to "gain" only in the two places that I mentioned, it doesn't explicitly explain every single setting; it's very possible that the camera has "gain" settings not explicitly discussed in the manual.

[Dave Humphries]

Hi Christina,

Your thirst for knowledge is admirable - but I think this is one area you don't need to worry about.

You have no doubt heard of that hideous disease of "pixel peeping"?
I think you have caught "EXIF exageratis", this is a new disease, perhaps not formally identified, until now

I had noticed this (somewhere) and put it to rest in my mind as something that (a bit like High ISO NR), the camera does for me and I don't need to worry about.

I guess if we're that interested, someone could shoot a test shot at every single iso value between 100 and whatever the top one is, then see when it changes. My guess would be "low" at 100, 125 and 160, then "high" at say 800 and over.

I wish you a speedy recovery,

[Manfred M]

Yes Christina, I am sure (I'm an engineer). The issue is the context it is used in is unclear. I wonder if it is a term that slipped through from the original Japanese translation of the camera manual, before some editor caught it and reduced the information to something aimed at photographers. Technically, when you are using the exposure compensation control, you are adjusting gain as well.

If you had a newer DSLR that shot video and were using video mode, the turn gain could also refer to the sound recording volume level. On my dedicated video camera, these controls are even marked "gain".

In terms of what Mike has written, this makes sense. If you are looking at doing an in-camera multiple exposure shot, you don't want the image to be overexposed, so by reducing the gain (exposure compensation) you can produce a properly exposed image.

[Brownbear]

Thank you.

Mike, I just shot a bunch of photos with auto iso set at a max of 800, and then I tried some at 1000 iso... I will check the data when I upload them. Later I will try just a set iso (no auto) and I will look at my settings and note, and post if it has something to do with this.

Dave,

"I think you have caught "EXIF exageratis", this is a new disease, perhaps not formally identified, until now." LOL

I'm not that interested in my EXIF. I was just worried that I was doing something wrong because I did not know what it was. If none of you are worried about it, I won't worry about it anymore, either... Miraculously cured. Thank you.

[Brownbear]

Thank you Manfred. Indeed, you sound like a brilliant engineer. Thank you for the further clarification in terms of Mike's explanation. Now I understand, and I'm fully cured.

Yes Christina, I am sure (I'm an engineer). The issue is the context it is used in is unclear. I wonder if it is a term that slipped through from the original Japanese translation of the camera manual, before some editor caught it and reduced the information to something aimed at photographers. Technically, when you are using the exposure compensation control, you are adjusting gain as well.

If you had a newer DSLR that shot video and were using video mode, the turn gain could also refer to the sound recording volume level. On my dedicated video camera, these controls are even marked "gain".

In terms of what Mike has written, this makes sense. If you are looking at doing an in-camera multiple exposure shot, you don't want the image to be overexposed, so by reducing the gain (exposure compensation) you can produce a properly exposed image.

[proseak]

There's a possibility that it refers to the display gain - on some cameras, this can be adjusted.

Do you use live view at all?

[Mike Buckley]

Do you use live view at all?

Her camera (Nikon D80) does not have that capability.

[Brownbear]

Thank you, Peter. I don't use live view, and I'm sure my camera does not have that feature. Thanks Mike.