It's pretty straightforward and is really handy when you want to capture pictures of the night sky without the SX40 stumping you with the ISO limitation. Even though you can mess around with longer exposures, this is probably the simplest way to do it however it will cause more grain than using a long exposure.
Tuesday 25 September 2012
CHDK Override ISO Video Up
The next video for Overriding ISO using CHDK is up.
It's pretty straightforward and is really handy when you want to capture pictures of the night sky without the SX40 stumping you with the ISO limitation. Even though you can mess around with longer exposures, this is probably the simplest way to do it however it will cause more grain than using a long exposure.
It's pretty straightforward and is really handy when you want to capture pictures of the night sky without the SX40 stumping you with the ISO limitation. Even though you can mess around with longer exposures, this is probably the simplest way to do it however it will cause more grain than using a long exposure.
Facebook based photography theme
I decided to run a photography theme over on the Facebook page just to give us something to challenge ourselves with! See Below for the post:
"Light and Shadow!
I'm thinking that's it's time to get our thinking caps on for some photography fun. If anyone is up for it, why not join in just for the challenge and if we enjoy it, we can make it a regular thing.
So let's do a photo theme! I can't really do prizes but it's really just for fun and practise and a change to get creative!
I think this week (may as well finish it on Sunday) can
"Light and Shadow!
I'm thinking that's it's time to get our thinking caps on for some photography fun. If anyone is up for it, why not join in just for the challenge and if we enjoy it, we can make it a regular thing.
So let's do a photo theme! I can't really do prizes but it's really just for fun and practise and a change to get creative!
I think this week (may as well finish it on Sunday) can
be related to light and shadow. Have you taken - or can you take - a picture that gives the feeling of the contrast between light and shadow?
It can be anything you like, and anywhere, from the shadow of trees as the sun goes down, to torches behind glass bottles or strange shapes you can turn into interesting shadows. Something like that.
As I said, a bit of fun but we will see how interesting everyone finds it ;) Enjoy!
P.S Don't forget to write in the description what you did to achieve the picture ;)"
It can be anything you like, and anywhere, from the shadow of trees as the sun goes down, to torches behind glass bottles or strange shapes you can turn into interesting shadows. Something like that.
As I said, a bit of fun but we will see how interesting everyone finds it ;) Enjoy!
P.S Don't forget to write in the description what you did to achieve the picture ;)"
Good Luck!
Tuesday 18 September 2012
Whoops!
Just a quick note to say that I have had to temporarily take down the Step Two for CHDK on Shutter Speeds as another user has informed me that my maths is off. Need to review the video but as I have made the rest of the series, I will continue to upload those whilst Im figuring it out :/
Monday 17 September 2012
Huh? ND In or Out? What's the deal?
So, for those of you who are venturing into the big bad world of CHDK and all the wonders it reveals, you will have seen the option in the Extra Photo Operations Menu for ND Filter State.
For those who don't know, an ND filter is a Neutral Density filter and is essentially darkened glass that is placed over the front of your camera lens. This glass allows you to take a photograph in a brightly lit environment without over exposing your image.
The most common example is with Waterfalls and rivers. Have you ever seen those pictures where the water looks so smooth and silky? This is done with a long exposure. Taking an image for approimately 1.5 seconds or more, allows the photographer to capture the motion of the water which leads to this very silky looking water.
However, if you have ever tried to take a long exposure of even half a second, in daylight, that image will be incredibly over exposed/too bright. So we place this dark glass over our lens. The dark glass means that light slowly creeps into the image, without flooding in too fast. This allows our picture to capture the movement of the water over time, e.g for 2 seconds, without too much light hitting the sensor too quickly.
The result? A nice balanced exposure, but that great smooth looking water from our long exposure.
Some cameras have a Neutral Density filter built in and those cameras apply the filter to images in this sort of situation. The camera is quite often doing this for the user without the user actually being aware of it.
When the camera has a built in neutral density filter, it will swing the filter down between the lens and the camera sensor to act the same way a filter in front of the lens would work - stopping too much light hitting the sensor too fast. The SX40 doesn't have a built in ND filter but the override in CHDK allows us to have a bash at it!
The options for the ND filter state can sound confusing but now we know how a built in ND filter works, we can understand the odd phrasing. The options for the Neutral Density Filter are Off (self explanatory), In (The filter is swung down in front of the sensor) or Out (The filter is swung out and not in use).
Assuming we had a camera with a built in ND filter we would have the following options with CHDK:
Off - Let the camera choose whether or not to use the ND Filter
In - Force the camera to swing the ND filter down in front of the sensor
Out - Force the camera to stop using the ND filter and swing it out of the way
As the SX40 doesn't have one built in, all we really need to see is Off and In options as Out will essentially be the same as switching it off for us.
When CHDK activates the ND filter state, it overrides our camera to allow a long shutter speed but maintains a darker image. As we don't actually have a built in filter, it can't work miracles and if you were trying a 15 second shutter in daylight, it can't actually override our settings in a way to stop that being over exposed but it certainly works to a point as I demonstrate in the new video.
I hope that's pretty clear and have fun playing around with it :)
For those who don't know, an ND filter is a Neutral Density filter and is essentially darkened glass that is placed over the front of your camera lens. This glass allows you to take a photograph in a brightly lit environment without over exposing your image.
The most common example is with Waterfalls and rivers. Have you ever seen those pictures where the water looks so smooth and silky? This is done with a long exposure. Taking an image for approimately 1.5 seconds or more, allows the photographer to capture the motion of the water which leads to this very silky looking water.
However, if you have ever tried to take a long exposure of even half a second, in daylight, that image will be incredibly over exposed/too bright. So we place this dark glass over our lens. The dark glass means that light slowly creeps into the image, without flooding in too fast. This allows our picture to capture the movement of the water over time, e.g for 2 seconds, without too much light hitting the sensor too quickly.
The result? A nice balanced exposure, but that great smooth looking water from our long exposure.
Some cameras have a Neutral Density filter built in and those cameras apply the filter to images in this sort of situation. The camera is quite often doing this for the user without the user actually being aware of it.
When the camera has a built in neutral density filter, it will swing the filter down between the lens and the camera sensor to act the same way a filter in front of the lens would work - stopping too much light hitting the sensor too fast. The SX40 doesn't have a built in ND filter but the override in CHDK allows us to have a bash at it!
The options for the ND filter state can sound confusing but now we know how a built in ND filter works, we can understand the odd phrasing. The options for the Neutral Density Filter are Off (self explanatory), In (The filter is swung down in front of the sensor) or Out (The filter is swung out and not in use).
Assuming we had a camera with a built in ND filter we would have the following options with CHDK:
Off - Let the camera choose whether or not to use the ND Filter
In - Force the camera to swing the ND filter down in front of the sensor
Out - Force the camera to stop using the ND filter and swing it out of the way
As the SX40 doesn't have one built in, all we really need to see is Off and In options as Out will essentially be the same as switching it off for us.
When CHDK activates the ND filter state, it overrides our camera to allow a long shutter speed but maintains a darker image. As we don't actually have a built in filter, it can't work miracles and if you were trying a 15 second shutter in daylight, it can't actually override our settings in a way to stop that being over exposed but it certainly works to a point as I demonstrate in the new video.
I hope that's pretty clear and have fun playing around with it :)
Wednesday 5 September 2012
Exposure Value and balancing light - Prepare your brain!
I have just uploaded a new video about Exposure Value and balancing the light in your image.
When we use the exposure meter on the camera it gives us an average balance of light to work towards to match the light in the room for an accurate picture. In a lot of situations, we may want this light to be a little brighter or vice versa but it's always handy to be able to find an average exposure level to begin with.
The exposure meter changes depending on what settings we are using, so when we make an adjustment to our Shutter Speed, Aperture or ISO, the light in the image changes and the meter will show us if those settings are causing the image to be over exposed (too much light) or under exposed (too little light).
The measurement of exposure is often referred to as a 'stop'. This is not referring specifically to just shutter speed, just aperture or just ISO, it is a combination of all of them. However when we are changing our exposure, the change we make is measured on a scale that uses the 'stop' system.
Stops for Shutter Speed are seen as this:
1/8000, 1/4000, 1/1000, 1/500, 1/250, 1/125, 1/60, 1/30, 1/15, 1/8, 1/4, 1/2, 1" etc
For Aperture:
f22 (f/22),16 (f/16), f/11, f/8.0, f/5.6, f/4.0, f/2.8, f/2.0, f/1.8 etc
And for ISO:
100, 200, 400, 800, 1600, 3200
So each of these numbers are a stop measurement.
If I had a shutter speed of 1/60 and I was told to increase my shutter speed by two stops, I would then change it to 1/250 as this is two numbers up the scale.
Sometimes we need to use a specific setting. As an example, if I wanted to take a slow exposure of water, but I had already balanced my exposure to 1/250 and f2.7 and ISO 400 then I would need to adjust my shutter speed - this would then put my exposure out of balance. But if we use the stop measurements as a guide we can easily get back to a balanced exposure without guessing at our settings.
So we have 1/250 SS, F2.7 A and 400 ISO but we want a shutter speed of 1/4000. So we are moving 3 stops up the shutter speed scale:
1/8000, 1/4000, 1/1000, 1/500, 1/250, 1/125, 1/60, 1/30, 1/15, 1/8, 1/4, 1/2, 1"
+3 +2 +1
So we have moved 3 stops and our image will be too dark as we have sped up our shutter and not compensated for the lack of light.
We can then balance this out by moving either out Aperture or ISO an equal amount of stops. In this situation, we started off with an Aperture of f2.7 and as this is the lowest we can go on the SX40 we won't be able to move this setting to let in more light. This leaves only our ISO to change, so we move our ISO 3 stops up the ISO scale in order to compensate for the Shutter Speed and to let in more light:
100, 200, 400, 800, 1600, 3200
+1 +2 +3
So we now have a new setting for our image of 1/4000 Shutter Speed, f2.7 Aperture and 3200 ISO which allows us to take that picture with a faster shutter, and to maintain a good level of light in our image.
It seems a little complex but it's actually quite straightforward.
One last thing to mention is that on the SX40 you can also do fractions of a stop so instead of our Shutter Speed jumping from 1/30 to 1/60, the SX40 allows us to use 1/40 and 1/50 too. These smaller fractions are not part of the scale to measure light changes. Only the parts of the scale that have a number above them are full stops. You'll see what I mean in the new video.
I hope that is fairly easy to follow as it isn't so easy to explain!!
When we use the exposure meter on the camera it gives us an average balance of light to work towards to match the light in the room for an accurate picture. In a lot of situations, we may want this light to be a little brighter or vice versa but it's always handy to be able to find an average exposure level to begin with.
The exposure meter changes depending on what settings we are using, so when we make an adjustment to our Shutter Speed, Aperture or ISO, the light in the image changes and the meter will show us if those settings are causing the image to be over exposed (too much light) or under exposed (too little light).
The measurement of exposure is often referred to as a 'stop'. This is not referring specifically to just shutter speed, just aperture or just ISO, it is a combination of all of them. However when we are changing our exposure, the change we make is measured on a scale that uses the 'stop' system.
Stops for Shutter Speed are seen as this:
1/8000, 1/4000, 1/1000, 1/500, 1/250, 1/125, 1/60, 1/30, 1/15, 1/8, 1/4, 1/2, 1" etc
For Aperture:
f22 (f/22),16 (f/16), f/11, f/8.0, f/5.6, f/4.0, f/2.8, f/2.0, f/1.8 etc
And for ISO:
100, 200, 400, 800, 1600, 3200
So each of these numbers are a stop measurement.
If I had a shutter speed of 1/60 and I was told to increase my shutter speed by two stops, I would then change it to 1/250 as this is two numbers up the scale.
Sometimes we need to use a specific setting. As an example, if I wanted to take a slow exposure of water, but I had already balanced my exposure to 1/250 and f2.7 and ISO 400 then I would need to adjust my shutter speed - this would then put my exposure out of balance. But if we use the stop measurements as a guide we can easily get back to a balanced exposure without guessing at our settings.
So we have 1/250 SS, F2.7 A and 400 ISO but we want a shutter speed of 1/4000. So we are moving 3 stops up the shutter speed scale:
1/8000, 1/4000, 1/1000, 1/500, 1/250, 1/125, 1/60, 1/30, 1/15, 1/8, 1/4, 1/2, 1"
+3 +2 +1
So we have moved 3 stops and our image will be too dark as we have sped up our shutter and not compensated for the lack of light.
We can then balance this out by moving either out Aperture or ISO an equal amount of stops. In this situation, we started off with an Aperture of f2.7 and as this is the lowest we can go on the SX40 we won't be able to move this setting to let in more light. This leaves only our ISO to change, so we move our ISO 3 stops up the ISO scale in order to compensate for the Shutter Speed and to let in more light:
100, 200, 400, 800, 1600, 3200
+1 +2 +3
So we now have a new setting for our image of 1/4000 Shutter Speed, f2.7 Aperture and 3200 ISO which allows us to take that picture with a faster shutter, and to maintain a good level of light in our image.
It seems a little complex but it's actually quite straightforward.
One last thing to mention is that on the SX40 you can also do fractions of a stop so instead of our Shutter Speed jumping from 1/30 to 1/60, the SX40 allows us to use 1/40 and 1/50 too. These smaller fractions are not part of the scale to measure light changes. Only the parts of the scale that have a number above them are full stops. You'll see what I mean in the new video.
I hope that is fairly easy to follow as it isn't so easy to explain!!
Tuesday 4 September 2012
Meeting fellow SX40ers and making those videos!
I was out in London Zoo (ZSL) yesterday afternoon and came across a fellow SX40er from youtube. It was a really nice encounter and quite a surprise but it's probably a good thing I was fatdragon as I can imagine a stranger being asked that question may have wondered why they looked like a fatdragon in the first place haha!
But back to business... I have made the most ridiculous mistakes in the la
But back to business... I have made the most ridiculous mistakes in the la
st month or so that are stopping me from making videos. If it's not cloudy, I have forgotten my charger or I have forgotten the battery or something like that and when I say I forgot them, I was moving around during the weekends and trying to get videos made on the move and as you can see... not working out too well.
So anyway, I am hoping that I have time this week to finally finish off the two videos I have been working on. The first was about using CHDK to take long exposures at night time, particularly for taking images of the stars. This was all going well until every night clouded over and I wasn't able to take demo shots so once I get those, that video is done.
The next video is talking about CHDK in more depth and my my there is a LOT to learn! I have been going through the menu thoroughly and there are many things I have to learn, practise with and look up before I can demo them in a video, hence why this video is taking longer to make.
Add on top of this, the fact that I am travelling every weekend and busy most weeknights and making videos becomes a little more difficult, but persistance is key!
I also have a giveaway video coming up after those two so keep your eyes peeled ;)
It's great to see everyones posts and experiments with photography so keep them coming!
So anyway, I am hoping that I have time this week to finally finish off the two videos I have been working on. The first was about using CHDK to take long exposures at night time, particularly for taking images of the stars. This was all going well until every night clouded over and I wasn't able to take demo shots so once I get those, that video is done.
The next video is talking about CHDK in more depth and my my there is a LOT to learn! I have been going through the menu thoroughly and there are many things I have to learn, practise with and look up before I can demo them in a video, hence why this video is taking longer to make.
Add on top of this, the fact that I am travelling every weekend and busy most weeknights and making videos becomes a little more difficult, but persistance is key!
I also have a giveaway video coming up after those two so keep your eyes peeled ;)
It's great to see everyones posts and experiments with photography so keep them coming!
Subscribe to:
Posts (Atom)