Showing posts with label histogram. Show all posts
Showing posts with label histogram. Show all posts

Monday, 2 February 2009

Techniques-Metering my way


Firstly there is no right way of metering a scene, As long as you get the right exposure in your image whether using Manual, Evaluative/matrix, Spot, Centre weighted or whatever its the final image that matters, I know that Martin is a fan of manual metering where he sets both shutter speed and aperture as he mentioned in his post, Well i am a fan of using AV and matrix metering where i set the aperture and control the depth of field but i allow the camera to set the shutter speed although i control this by using exposure compensation if needed, When i used the Canon 1D MK3 i used to start by flicking on the live view feature and view the live histogram,check this and adjust as needed, This way i knew that when i took a shot the exposure would be spot on, A great feature and one i really miss on the Nikon,These days Camera metering is extremely accurate and using both the Canon and Nikon systems i can say that the Nikon system is between 1/3 and 2/3 of a stop better in keeping whites from blowing, I noticed this when shooting side by side with another Canon photographer who was compensating more than me to stop his whites from blowing, This all helps when processing meaning that you need to adjust less to bring the whites or shadows up, I do in certain circumstances use manual mode,These would normally be in heavy snow where i set the camera to manual and spot metering, After i have set the aperture that i want i will then take a reading off of the snow and add 2 stops, This keeps the whites nice and white, I always do a test shot after setting up and then compensate as necessary, I also use manual when shooting at night for badgers, Here i am using flashguns to emualte daylight and know that the light will be constant which is the important thing when using this mode, I have in the past used manual mode in constant light for birds in flight but this is more of a whim for me as i get just as good results using AV, When i set up for manual like Martin i tend to look for a mid toned object (doesn't have to be grey-Could be mid Red,Blue,Green) and meter off of that but if you understand tones you can meter off of parts of the sky and add +2/3,Off of a white subject like a cloud and add between 1.5 and 2 stops or even off of a black subject and take away 2 stops, Its all down to the tone, The histogram that you get with a digital camera is your best friend along with the flashing highlights you should always have a correct or near as damn it exposure, I am a fan of exposing to the right and started to slightly over expose my images before i had ever read about it, It started when shooting Chamois in snow, By slightly over exposing but making sure i didnt blow the whites i noticed that i had better detail in the dark fur, You need to learn to read a histogram and understand what the tones are that are in it, By exposing to the right you are making sure that the maximum amount of tones are present in the image and can then adjust the exposure in processing, Adjusting slight over exposure doesnt cause grain to appear in the final image but bringing up a dark exposure does,This becomes more important when using high ISO where grain can start to show, Careful exposure means that there will be less processing and as such less grain, Once you have used your choice of metering for a while things will start to come naturally and when you look at your subject say a swan you will know of using AV/Evaluative metering that you will need to compensate by say -1/3 or -2/3 to stop the whites blowing-practice,practice and then practice some more and keep an eye on your best friend-the histogram


Dave

Wednesday, 21 January 2009

Seize the moment


I am very lucky being able to shoot when i want and not have the confines of weekend and holidays, Yesterday was a prime example and when i woke up and looked out side i could not believe that there was snow and that it was still snowing hard, Being away for a few days i hadnt seen the weather forecast so was totally unprepared so plans had to be made on the spot, Its not very pleasant to drive when the weather is so bad so i decided to grab my pop up 2 man tent and put it near my bird feeders,The birds would be cold and hungry and will be easier to shoot, I used the tent as opposed to a hide as it has a built in ground sheet and as i wanted to be low level meant that i could sit on the ground,It is also double skinned so would help keep me warm,

I dressed in multi layers and ended up in the tent for about 6 hrs and still felt fine,I made sure that i kept my gloves and hat dry when i left the tent as this is were the body heat will be lost, Its also worth remembering that you dehydrate when you are out in the cold for long periods as you do in heat so make sure that you have plenty of warm drinks during the day, As soon as i put some fresh food out and got into position the birds started to arrive and there was a constant stream all day,I had to top the feeders up 3 times!! When shooting in snow i set my camera to manual and spot meter directly off of the snow, I then add 2 stops as the white snow will try to fool the camera into under exposing leaing to a dark grey image,Once set i take a test shot and checked the histogram,It depends on how much sun there is on the snow but yesterday with heavy cloud and snow coming down it was spot on,The histogram was way to the right but there were no 'blinkys' showing, i had placed a log on the ground a few weeks before so i sprinkled some food on tht and then had a flat tray that had a branch strapped above it and i put food there,I didnt fill the other feeders that i had as i wanted the birds infront of me, The only bird that i really wanted to get but never came to feeders in front of me was the tufted titmouse-a beautiful bird and one that i would love to get with the snow falling, There are 2 that visit my garden and they were around yesterday but it just never happened, I was pleased to end the day with some very nice images,The snow acts as a reflector and the images end up nice and evenly lit, I put some corn out hoping that the deer that visit my garden may come out early but i watched them come out and start feeding when there was little light so left them to it,