Showing posts with label photography. Show all posts
Showing posts with label photography. Show all posts

Tuesday, September 21, 2010

HDR - exploring exposures beyond limits..


We are always wondered by the beauty of sea waves, land scapes in foreground with bright colourful background sky, through our eyes. But when you look through viewfinder of a camera, it may not be so beautiful because either foreground become dark or background become over exposured. I have posted some techniques in earlier blogs.
Here i introduce you to a new world of HDR, high dynamic range photography... mixing images of a range of exposures by taking a series of images with varying shutter speed..
here i paste a tutorial to do HDR photogrphs in photoshop, for that you need a plug in for HDR like photomatrix.. please download it.
take an image of foreground or background with suitable shutter speed.. then change shutter speed gradualy with capturing untill it covers the remaining parts of image.. first start from 3 images...

1
Start with 3 images. One normal exposure, the second underexposed and the third overexposed. In this case I used 2 stop bracketing. As I shoot a lot of city scapes I can get away with 2 stops, because I'm mainly shooting flat surfaces and banding and posterization isn't such a problem. If your shooting rounded and curved surfaces you will want to lower your bracketing to get smoother gradients.
I set the bracketing on my camera to 2 stops. Then I set the shooting mode to burst. When I hold the shutter down, 3 photos will be captured. I shoot in RAW mode for the widest possible dynamic range. You can still create HDR if your camera doesn't support RAW. Make sure you shoot in Aperture Priority or in Manual. You want to bracket the exposure time, not the Aperture. If you change the aperture, the depth of field won't be consistent and you'll get blurring. Also avoid any moving subjects in the photo or you'll get ghosting.

2
Time to merge the photos together into a single 32 bit image.
Choose File>Automate >Merge to HDR. This works on Photoshop CS2 and CS3. (CS2 Doesn't have auto align). Choose either images or folder. I organize each set of photos in its own folder so I used the folder option. Select your photos to merge. Turn on Auto Align in Photoshop CS3. Click OK. (Photoshop CS3 uses new Auto-align technology that even allows you to create HDR without the use of a tripod!)

3
Your images will now be merged into a single photo. You can turn off individual photos by un checking their boxes on the left filmstrip. If you get some blurring caused by camera shake in the longest exposure, you may want to turn off that photo.

4
The merged result is a floating-point 32 bit image. You can adjust the overall tones by sliding the White Point slider. Easy with it, a little movement goes a long way!
5
Click OK to merge the photos into a 32 bit image. Now is a good time to save your file.

6
In order to use the photos, you'll need to convert them t 16 or 8 bit images. When we convert them we will create what I call interpretations of the photo. The reason I say this is because we have unlimited ways we can make the photo look. While we have this huge dynamic range available in 32 bit, we will no longer have those options after conversion. Always work from the saved 32 bit version, and then convert and save versions (personal interpretations). Avoid overwriting the 32 bit image, it's our master and we may want to go back to it many times.
Choose Image>Mode>16 bit (or 8 bit). Now we get to play with some fun options. You're now at the tone mapping part of the process. This is were all the creativity can ooze.
(If you want to make the adjustments without converting, choose view>32 Bit Preview Options. You can use several of Photoshop's tools in the Image>Adjustments menu. The most important of these is the Exposure control)
You'll see an HDR Conversion Dialog box. Exposure and Gamma is the default option. Best way to approach this? Set the gamma first, then adjust the exposure to suit. If you want an image with lots of contrast, lower the gamma. For less contrast raise the gamma. Finally, adjust the exposure to get the desired brightness. If you want more control, read on... otherwise press OK to convert.

7
Change the Method to Local Adaption. (There are 4 available methods, but these are the only 2 with user input).
With local Adaption, you can adjust the curves. Set these like you would normally work in curves, but don't be afraid to clip the histogram a little. You can clip because your working with a larger dynamic range than you're used to. Bring out the detail in the image, but don't forget to put some shadow in there or it will look washed out and fake. Once your happy with the curve, adjust the radius and Threshold sliders to make sure there are no halos in the photo. (Badly converted HDR images have a glow around the areas of contrast.) The radius controls the mask blur while the threshold decides what gets blurred and what doesn't.
Click ok to convert.
8
Here we have a merged image from HDR. The second image is a variation. In the second variation, I applied exposure, curves and sharpening settings while in 32-bit mode (Highlight Compression Method). Photoshop is great for producing very realistic HDR images.
9
If your desiring a more surreal result there are different plug-ins that you can use. My favorite is Photomatix pro from HDRsoft. You can just get the tone mapping plug in for Photoshop which works great.Using photomatix tone mapping plugin allows you to get highly detailed textures in your photographs. You merge in Photoshop as shown in this tutorial. Then choose Filter>Photomatix to apply tone mapping. Convert and save as normal.

Monday, July 26, 2010

Canon EOS 550 D... revolution from entry level..


I think this is the first DSLR from entry level price around 0.5 lakhs at perfection. eos 7D, eos 50D, nikon D90,D300 the most widely accepted DSLRs within a range of 1 lakh. But with the announcement of the 550D canon has changed entire price face.


It is supported with 18.1 mp sensor, 63 point metering dual layer sensor,3.7 fps shooting, 1920*1080 HD movie, large ultra fine LCD screen, redefined buttons, iso up to 12800, hdmi control... and a lot more..

it holds compatibility to all EF and EFS lenses.

Experts tells that it is 99% eos 7D... a little bit slow when compared to 7D.. but to others it is best and sometimes out stands 50D.


This enables all the budding photographers especially wildlife, to shoot up to a standard professional level. It is worth buying it with a suitable lens. and go for an outstanding shoot in the wild..

Tuesday, March 30, 2010

Are you troubled with high contrast metering...???


at field we find many difficulties in taking a good photograph.. one of the most faced problem is metering problems in high contrast.. that is when you take a photograph of an object in bright background you will miss either foreground or background..
for example if you are taking a photo of an bird in very bright sky you will miss either sky or bird..
there are many solution for this.. most easy methods from my experiences are
1) taking photograph in morning and evening.. this will provide you low contrast..
2) providing sufficient light to object.. this will help you to bring object to high brightness and in camera you can reduce the EV and take good photograph..
3)mixing the two photographs metered at foreground and background.. simply take the 1st photograph metered to object.. adjust the EV to object.. without changing the frame take the second photograph metered to background.. paste these photographs to a photoshop window erase the unnecessary parts carefully.. this is very simple..
try these tips ... i got these from my experiences..

Sunday, March 28, 2010

Parambikulam... paradise of wildlife photography


Parambikulam is one of the largest and most protected wildlife sanctuaries of western ghats..
it holds many type of vegetation, forests and a very diverse fauna.. wild animals can be seen very easily if you go with enthusiasm..
we visited this beautiful place in march 2010.the first thing which attracted me the most is parambikulam offers infinite scope for photography.. if you own even a compact camera you can make good photographs.. but i prefer a slr with telezoom lens.. sure you can do miracles if you love animals and photography... from my experiences, in this summer season it will be better to take a solar filter with you.. because, there is no abundant foliage there, so the chance of sun glare is very high except in dawn and dusk..
please carry a tripod also with you.. you will get much time to do photograph and there is no difficulty to place a tripod in this forest.. if you go to evergreen part monopod will be better..
with these beautiful fauna and Flora.. landscapes, dams also gives good frames..
and also it offers a great opportunity to study the mammals and birds.. my favourite fauna groups..