So which one is right?

[bernhund]

Stupid problem this, but I really don't know the answer! So here's an example:
I take a photo with my Nikon D7100 and assume the exposure should be correct for my subject (particularly if spot metering is used on the subject). I load it into my computer, which I can adjust the brightness of the screen on (problem 1: Which screen brightness shows me what the camera should have produced?) Then I upload the image to Lightroom and hit the 'auto' button for exposure etc. (problem 2: It either under/over or lightly tweaks my original image. So which one is right, Lightroom or camera?). Next I might also open the same image in Photoshop (problem 3: Photoshop shows my image at a different brightness to Lightroom). So where on earth does this leave me when trying to produce the perfect exposure on my screen, so that when I send the image to a printers like Photobox, it comes back perfectly exposed? HELP!!!

(I might add that I don't necessarily use 'auto' on Lightroom, but regardless, I still don't know if what I'm looking at and tweaking is actually making the image straight from camera worse)

[bernhund]

Simpo Two said:

Never trust your camera to get the exposure right. Always use the histogram so you can see exactly where the whites, blacks and midtones are and where they should be. You can also see this in Levels in PS. Calibrate your monitor so that what it shows you is accurate (that's what a 'monitor' originally was). Treat 'Auto' (whether exposure or WB) with caution - sometimes it does a great job, at others quite the reverse. It all depends on the shot. As for getting your prints back how you expect, ultimately there can be a bit of trial and error but remember the settings that work and eventually you should crack it.

Thank you John. So the best bet is to learn about histograms! I've looked these up on YouTube, but still don't really get it. So, any advice on the best place to start with this?

[bernhund]

This is why I get confused! A high key studio portrait of a blonde wearing white with a white backdrop would surely show a very steep climb to the right and virtually empty on the left, yet the image would be correctly exposed...there's just no black/little mid tones. No doubt 'auto' in PS would under expose it.

[bernhund]

Simpo Two said:

bernhund said:

This is why I get confused! A high key studio portrait of a blonde wearing white with a white backdrop would surely show a very steep climb to the right and virtually empty on the left, yet the image would be correctly exposed...there's just no black/little mid tones.

Correct. A pure white background would either be a spike mashed up against the right hand side or you might not even see it. What you're looking for is the small hill that represents the subject. To be visible, the woman's white clothing would technically be very light grey, at least where it meets the background. At this point you'd probably wish you'd used a black background!

Once you get the image into PS you can use Levels to push the 'hill' left or right - you'll see the effect it has - and Curves to increase particular areas of it. That's a very simplistic explanation and I'm not a PS expert by any means, but it works for me.

I need PS lessons! And maybe something better than a 17in laptop!

[bernhund]

Simpo Two said:

RobDickinson said:

But if you are in any metered mode (aka outside of M mode without auto iso) you need to help the metering even so. A dark bar scene will need -exp comp, skiing will need + exp comp

Yes, I'm a great fan of +/-EV.

This is another point at which I get confused! If you're shooting RAW and the metering in camera can't be trusted, then do you not compensate anyway in post processing? Any alterations in PS for exposure would do the same as EV would it not?

[bernhund]

RobDickinson said:

Ev comp changes the exposure, shutter speed or aperture so it's not the same as doing things in post.

What you are doing is telling the meter it's actually lighter or darker

I'm sorry Rob, I just have one of those quizzical brains! So EV will adjust aperture and/or shutter speed to compensate? Does that then take away the shutter/aperture that you wanted/planned, when you could over/under expose by bracketing?