[Paul B]

I've noticed recently that I've been underexposing my images consistently and whilst the highlights might thank me for that I'm doing it by considerably more than I ought.

This becomes a bit of a pain on relatively high ISO shots when I push them in RAW. I've been trying to be less of a newb and actually use the histogram which helped a bit on Sunday but I was still a stop under as the images started to look blown out on the back of the camera and I 'chimp' a lot when playing with flash.

Is there a good way of calibrating this (grey card? although I read something regarding 18% grey and metering yesterday) or is it just a trial and error process?

Furthermore the colour between the back of the camera and the monitor is very different (even when I apply the relvant picture style to the RAW file) and I'm aware that I'm tweaking things on a non calibrated monitor which could be a nightmare.

What are the best options for aiming for true colours (Without spending a load on a colour Munki or something)?

[slackline]

I borrowed a Pantone Huey off a mate who splashed out for one, it appears to be considerably cheaper than a colormunki (obviously I used it under Linux and therefore used the dispcalGUI which is a front end to Argyll CMS).

Should probably redo my monitor calibration soon.

[Johnny Brown]

I've been trying to be less of a newb and actually use the histogram which helped a bit on Sunday but I was still a stop under as the images started to look blown out on the back of the camera

Don't worry about what the images look like, just look at the histogram. Turn on the blinking warning for blowing highlights and make sure you white balance before capture - the histogram is based on the preview which is a jpeg not the raw file.

For monitor - hire this guy for an hour. http://scs-imaging.co.uk/

He'll be able to calibrate your monitor for the next few months at least, or tell you if its not up to the job, or whether it needs more regular calibration. All a lot cheaper than paying £££ for a puck when your monitor is fucked/ shit. You'll probably pick up a few other tips for free too. Thanks for Grimer for the tipoff, this guy is REDHOT.

[Paul B]

Don't worry about what the images look like, just look at the histogram.

Unfortunately my middle name isn't 'Mcnally' so I need to take a peek in order to know what each light is doing.

hire this guy for an hour.

How often do you get this done? I'm hoping the monitor is up to it, its fairly new and cost enough.

[Johnny Brown]

I've had it done once when I thought my colours were off. He fixed it. I may get him round again soon (6 months later) to check it hasn't drifted, but mainly to pump him for info on flatscreens...

[dave]

Unless you're pulling CRTs on their last legs out of a skip Paul then I wouldn't bother getting the man in. I'd start off with a simple calibration by eye by going through the wizard in Adobe Gamma - this should get you a very decent result (granted this is easier/more reliable on a CRT than an LCD). If you want to go down the hardware route I've got a Spyder thing you can borrow.

This still won't get youa  result that necessarily matches your camera screen though, cos the camera screen ain't calibrated.

The one thing I will say is most digitals seem to come with the screen brightness dialed up to crazy levels by default. I always have to turn mine down pretty low to get something that looks right - when I first had my D70 i thought shit looked underexposed on the PC till I clocked that the LCD was way too bright on the factory settings. But then you should, like JB says use the highlight clipping and histogram as the real indicator.

[The Aaronator]

I calibrate my monitors at work once every term but I could get away with leaving it a bit longer as the colours don't drift very much at all. I think it depends on the type of monitor. Most of ours are now LED which are great (although a little uneven across the screen), but we also have some TFT Macs which are a couple of years old and are rubbish (IMO). You should, at the very least, do a visual calibration.

The screen on your camera will not be accurate at all and the image always appear brighter (and more blown out) than the downloaded file. You could try dimming the screen to match your 'calibrated' output. Trust the histogram and don't worry to much if its hitting the righthand (highlight) end, you will be supprised how much information can be pulled back in your RAW file converter - if anything, it may even be better to over expose slightly and bring your exposure down to suit in the software rather than brightening a dark image and so increasing horrible noise. That said, you cannot go wrong with a properly exposed image and a grey card is great for this if you know how to use it (it will also help you reproduce neutral colour). You really need to experiment...

[Paul B]

Unless you're pulling CRTs on their last legs out of a skip Paul then I wouldn't bother getting the man in. I'd start off with a simple calibration by eye by going through the wizard in Adobe Gamma

I'll give it a whizz

The one thing I will say is most digitals seem to come with the screen brightness dialed up to crazy levels by default. I always have to turn mine down pretty low to get something that looks right - when I first had my D70 i thought shit looked underexposed on the PC till I clocked that the LCD was way too bright on the factory settings. But then you should, like JB says use the highlight clipping and histogram as the real indicator.

I do use the blinkies and histogram for that but when I'm setting light ratio's I need the preview as well, it'd be nice if it was roughly right. For instance, I was happy with my ambient ratio to flash (for which I had to  rely on the preview) and the other two/three lights but they were all consistently under (which the histogram did show).

If its just dialling it down until it looks correct then I'll tether it and compare until I'm happy. Or shoot solely on the histogram and adjust the brightness down until it looks right!

@Aaronator - I'm confused, expose to the left or right for digital?

[The Aaronator]

@Aaronator - I'm confused, expose to the left or right for digital?

I would expose to the right if there was a lot of dark/mid dark tones in your images and noise is a concern. It depends on the highlights of course. I would never under expose a digital image i.e. push my mid tones to the left of in the histogram. But as I said, you cannot go wrong with the correct exposure

[cofe]

If you're only shooting raw and not jpeg, consider dialling the contrast sharpness and saturation down to get a more realistic histogram for the raw. If you're on Win7 pu won't have adobe gamma, and the in built OS calibration isnt great.

I'm not convinced by the expose to the right guff, instead trial error and experience should help you get the right exposure or close to it.

[Tom de Gay]

Is shooting tethered an option? It's a big help when you're faffing with lights.

I guess a D3x would also help...

[The Aaronator]

I'm not convinced by the expose to the right guff, instead trial error and experience should help you get the right exposure or close to it.

I think you have to remember that he is shooting at a high ISO which is going to appear noisy at the correct exposure and even more so when he has to brighten the image in whatever software he uses. As I said, you cannot go far wrong at the correct exposure, but you will also find that you can reduce noise by exposing to the right - different cameras have slightly different responses and I agree that trail and error, experimentation, experience will win the day.

[cofe]

As long as you haven't binned highlight detail, which is much more important than shadow detail.

[The Aaronator]

As long as you haven't binned highlight detail, which is much more important than shadow detail.

I agree, but you will be supprised how much detail is recorded in a RAW file even if the highlighs appear to be blown out.

[The Aaronator]

A useful article regarding Histograms and exposure can be found here: http://luminous-landscape.com/tutorials/expose-right.shtml

[Paul B]

If you're only shooting raw and not jpeg, consider dialling the contrast sharpness and saturation down to get a more realistic histogram for the raw. If you're on Win7 pu won't have adobe gamma, and the in built OS calibration isnt great.

I am on Win7.

Is shooting tethered an option? It's a big help when you're faffing with lights.

Tethered is an option at home and might be a way of comparing on camera-screen results to actual results and adjusting brightness, contrast etc. as Cofe suggested.

Please don't get me wrong, I was bitching about noise a lot a few months ago and it was entirely self inflicted. As the light felloff on Sunday I bumped the ISO to keep the shutter speed nice and high as Second curtain sync isn't an option without switching over to all optical slaves and one on camera (or at least on a cord, I find this pretty frustrating at times)!

I guess a D3x would also help...

Can't quite stretch to that, a 5d MKII on the other hand, I'd have lept if it didn't mean sacrifcing lense coverage 

[The Aaronator]

I did a quick and not particularly scientific test to check my facts: Is over exposing, or exposing to the right of the histogram beneficial in the reduction of noise.

I shot these images on a Nikon D200 at 400 ISO in RAW



This image, 'NormB' was taken at the correct TTL meter reading (I know the colour is not correct)




This image, 'plushalfB' was half a stop over exposed and the exposure brought down .55 in Adobe Camera RAW converter to match the brightness of the previous image. As you can see, apart from some small contrast and tonal differences (that can be fine tuned with more time), the images appear fairly similar.


normB  plushalfB

Now compare the apparent noise in each shot. The noise is less apparent in 'plushalfB'.

So, if you want to reduce or control noise in your photography, especially at higher ISOs, then slightly over expose your shots. Try half a stop over the meter initially (depending on the highlights) but experiment to find your cameras optimum range in different conditions.


Incidentally, the shot below is image 'plushalfB' without RAW exposure compensation. Some of the highlights threw up 'highlight' warning on the camera preview but the detail came back fine in RAW compensation.

If you're only shooting raw and not jpeg, consider dialling the contrast sharpness and saturation down to get a more realistic histogram for the raw.

This is a useful bit of advice that I also tested. By going into the camera's menu, finding the Optimise Image setting and changing it from Normal to Softer actually altered the Histogram appearance even though the output was set to RAW - It seems to give at least an extra 1/3 a stop of exposure room towards the highlights. And of course, you could also bring the brightness of your preview screen down to match your computers (calibrated?) monitor.

[Paul B]

Aaron - this popped up on the Strobist forum a couple of days ago and the approved beta (no heels etc.) seemed to be overexpose by 0.3ev and pull it back in RAW.

I've tried getting the camera and the screen as close as possible by trial and error:

Currently my LCD is dialled down one level and I've turned the picture style to Faithful/Neutral (I haven't worked out which is better yet, they both seem to be zero'd but they differ!).