Histogram
- Thread starter gabe
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no, it's not strictly necessary to learn it, you will be able to take good pictures without the knowledge.
However, you should learn about it so you can understand how it helps to make a good image, and more importantly, how to try and understand when something doesn't come out well.
My wife took some nice images on my camera at a wedding on sat. Camera was set to auto mode.
It really depends on how deep you want your knowledge to be
However, you should learn about it so you can understand how it helps to make a good image, and more importantly, how to try and understand when something doesn't come out well.
My wife took some nice images on my camera at a wedding on sat. Camera was set to auto mode.
It really depends on how deep you want your knowledge to be
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Not necessary but certainly very useful. Basically it is a quick check to see if you shot is under/over exposed.
It is best to use the RGB histogram as the average brightness one can be misleading.
For 99% of shots, the right hand side of the rightmost curve (whether blue, red or green) curve should NEARLY touch the right hand side of the graph. This will ensure good highlights without blowing them out. After this is done, any other exposure changes can be done PP.
It is best to use the RGB histogram as the average brightness one can be misleading.
For 99% of shots, the right hand side of the rightmost curve (whether blue, red or green) curve should NEARLY touch the right hand side of the graph. This will ensure good highlights without blowing them out. After this is done, any other exposure changes can be done PP.
I found this useful too as although I had some understanding it had not been explained that well before. Presumably I can use the live histogram on live view setting then if all is well, switch off live view and shoot as normal?
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As long as your light isn't changing I can't see why not.
I just tried it and it worked well. Although the dynamic range was too great to get a good shot stright out of the camera, I was able to keep it within the range where I could improve it easily with PS.
I will try the HDR technique described in the tutorial for which there is a link in the histogram tutorial but am wondering whether this is the best method or whether I should buy graduated filters. I will probably go for a 10 stop filter at some stage and was considering ND grads but they're very pricey and I imagine a lot of hassle. Should I bother with ND grads or concentrate my efforts on HDR?
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You get better results and more control using HDR than with graduated filters. But you have to faff about in post processing and it's always nice to get it right in camera. Also, unless areas of the subject break the grad line, eg buildings and mountains, grad filters do give a very good result.
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Here's another good link on histograms http://www.sekonic.com/images/files/HistogramsLightmetersWorkTogether.pdf
Histograms are obviously very useful, and essential if you want to try the 'expose to the right' (of the histogram) technique - basically for maximising shadow detail.
Personally, I find blinkies are more helpful most of the time - that's the highlight over-exposure warning that you can set to flash on the LCD image. But using the histogram and blinkies together is a very easy way of getting optimum exposure.
Histograms are obviously very useful, and essential if you want to try the 'expose to the right' (of the histogram) technique - basically for maximising shadow detail.
Personally, I find blinkies are more helpful most of the time - that's the highlight over-exposure warning that you can set to flash on the LCD image. But using the histogram and blinkies together is a very easy way of getting optimum exposure.
I've just switched the blinkies on so will try that tomorrow. I don't mind a bit of post processing but am wary of HDR looking over done. The issue I have with the filters is cost, faffing around and the risk of underexposing features above the horizon.
I've just bought a polarizing filter (I snapped up a Hoya HD at a good price) so have a fair few things to experiment with! I think I'll play with HDR first and see how I get on then consider ND filters in future (though I wouldn't mind a 10 stop for the effect on moving water).
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Blinkies are a brilliant aid
They not only tell you that you've got over exposure, but exactly where, and how much. They will flash in most images in bright sun for example, on specular highlights, but that's usually to be expected (and actually what you want). You can choose to ignore them or compensate as you think fit, whereas with the histogram you might only see a tiny peak and have no idea which part of the image is affected. Try the test quiz on the link I posted above, matching the images to the histograms - it's damn hard!One thing to remember is that everything you see on the LCD - the image, histogram, blinkies - is all generated off the JPEG and will show all camera settings including picture styles, white balance etc.
The thing to be particularly wary of is the contrast settin in picture styles which can will shift the histogram and also the trigger point at which the blinkies flash. There's more than a stop between max and min contrast. The thing to be aware of is just how much headroom you've got on the Raw file, and the contrast settings affects that. Some people like to keep the contrast at minimum to help with this but it doesn't really matter so long as you know where you are with it.
If you are happy with a bit of post processing, HDR will always get you result that is at least as good as using a grad, and usually better. You have total control and can make it as subtle or silly as you like. If you set the camera to shoot an auto-bracket sequence - say normal expose, then +2 and -2 - it will rattle off a set for HDR treatment in less than a second. The only drawback is with subjects that move between frames, but you can even get around that by carefully exposing a Raw file and compressing the dynamic range that already exists within that one image and is usually lost. The result is much more subtle than you can get with multiple exposures, and TBH no substitute for a grad, but sometimes that's what you want.
By blinkies, do you mean switching the highlight alert on? That's what I have done.
I tried the test and the one of the girl was easy enough but not the others.
I'll have to read your next bit again in the morning as my head's a bit fuzzy from information overload.
Regarding post processing, I tend to get reasonable results but don't really have a clue if I'm doing things right.
I tend to play around with the basic settings in raw and the lens correction then open the image and make adjustments such as adjustment layers and highpass filter but have also tried some of the tutorials. I would like to learn more about all this as it would be good to have a better understanding of what to do and the techniques involved but I'm no professional so can't spend all my time on it. Perhaps I should try and find a decent but fairly basic book on PS.
I tried the test and the one of the girl was easy enough but not the others.
I'll have to read your next bit again in the morning as my head's a bit fuzzy from information overload.
Regarding post processing, I tend to get reasonable results but don't really have a clue if I'm doing things right.
I tend to play around with the basic settings in raw and the lens correction then open the image and make adjustments such as adjustment layers and highpass filter but have also tried some of the tutorials. I would like to learn more about all this as it would be good to have a better understanding of what to do and the techniques involved but I'm no professional so can't spend all my time on it. Perhaps I should try and find a decent but fairly basic book on PS.
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Yes, blinkies, highlight alert etc.
When you've got your head around that stuff, have a look at Expose To The Right technique. It's on the link that Grendel posted, but here it is http://www.luminous-landscape.com/tutorials/expose-right.shtml
That's really the final frontier as far as exposure is concerned with digital (IMHO) and if you're prepared to do a little bit of post processing of Raw files, it will add that final bit of polish. Basically what it is doing is utilising every drop of data capture that the sensor is capable of, much of which is often wasted. It usually results in an image that looks over exposed on the LCD, but when you pull it back down again in post processing, the shadows in particular look much better - more tone separation, more detail, less noise
It will also help you understand HDR better.
When you've got your head around that stuff, have a look at Expose To The Right technique. It's on the link that Grendel posted, but here it is http://www.luminous-landscape.com/tutorials/expose-right.shtml
That's really the final frontier as far as exposure is concerned with digital (IMHO) and if you're prepared to do a little bit of post processing of Raw files, it will add that final bit of polish. Basically what it is doing is utilising every drop of data capture that the sensor is capable of, much of which is often wasted. It usually results in an image that looks over exposed on the LCD, but when you pull it back down again in post processing, the shadows in particular look much better - more tone separation, more detail, less noise
It will also help you understand HDR better.Yes, blinkies, highlight alert etc.
When you've got your head around that stuff, have a look at Expose To The Right technique. It's on the link that Grendel posted, but here it is http://www.luminous-landscape.com/tutorials/expose-right.shtml
That's really the final frontier as far as exposure is concerned with digital (IMHO) and if you're prepared to do a little bit of post processing of Raw files, it will add that final bit of polish. Basically what it is doing is utilising every drop of data capture that the sensor is capable of, much of which is often wasted. It usually results in an image that looks over exposed on the LCD, but when you pull it back down again in post processing, the shadows in particular look much better - more tone separation, more detail, less noise
I've read that thanks and many other of his pages. Most helpful. I'm glad I did too as I had always thought that an underexposed photo was easier to recover than overexposed and therefore erred on that side. (I guess this might be true) but what this is saying is get the exposure as high as possible without blowing the highlights.
Assuming I do this, what settings should I be adjusting in RAW to "pull it back down"?
Thanks for all this by the way - I feel like I am really getting somewhere.
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You've just got to darken everything.
As you will have read, what ETTR technique does is push everything up the exposure scale. The sensor records far more detail in highlights than in shadow areas (loads more) and this results in the subtleties of the shadow tones being much more clearly differentiated. And noise reduced, sometimes by a lot.
When you pull it back down in post, of course everything goes darker again (unless you choose not to do that, you have the option) but the separation remains. The result is more 'luminous' detailed shadows, with clear shades of darker tones and minimal noise, whereas they would normally just clog up to one shade of mud.
It's an advanced technique, sometimes it doesn't make much odds - it depends on the subject, and also on your output medium. If it's a small screen image, you'll not see much if anything, but on an A3 print with lots of shady yummyness going on it's well worth the effort.
Marc
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Me too.