in need of HDR tutorial

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aguilera1723

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Edit My Images
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one day i came across a picture that took 2 hours of my time.. and i did some research and it happed to be a HDR image...
now im dying to get the same results or similar.. i own a nikon 80.. just want to know if is enough to get some good results.. if anyone has a tutorial or if people can throw the basics around here.. that would be GREAT!!
 
Use a program like Photomatix to convert a RAW file into HDR for you. Very simple!
 
well.. i tried a similar program for linux distributions.. and the only problem im getting is that my final work has too much noise.. and it looks awful
 
Yes, originally my HDRs contained a fair amount of noise. If using Photomatix, make sure noise reduction is on. Use as low ISO as you can get on your camera if it's really bad. If you needed, it's possible to create the HDR and then go into photoshop or similar and reduce the noise there.
 
3 bracketed exposures merged to HDR will have less noise compared to one RAW merged to HDR.
 
can someone tell me how to merge 3 bracketed exposures so i can have one final image to work on.. i guess thats the process.. some knowledge please!! haha thanks everyone! im learning so much
 
i found a new setting on my sony last night that takes 3 photos at 3 different exposures,if i put these 3 together would that make a HDR photo??
 
Boris said:
3 bracketed exposures merged to HDR will have less noise compared to one RAW merged to HDR.
Click to expand...

And seven or more exposures is even better.

Noise usually indicates:
  • The full dynamic range of the scene hasn't been captured - not enough exposures; and/or
  • The gap between exposures is too great

Scenes vary. You might get away with three shots +/-2 in some situations.. but a church interior with deep shadows and bright stained glass may easily have 10+ stops of range in the scene.

I think the most I've ever used was 1 stop increments from 1/200th to 4 minutes in Ely cathedral. I could probably have dropped three or four exposures though without making much of a difference.

To merge exposures I recommend FDRtools, although the choice of the majority seems to be Photomatrix. I think the popularity of Photomatrix is down to three things.. it does far too much processing (it offers extra processing you'd be better doing properly in LR or PS).. it features in the more popular tutorials.. there's a 1001 dodgy registration keys in circulation. I'll let you decide which I think has the greatest bearing on its popularity.
 
Most SLR have the AEB facility which allows the user to set the exposure from as low as -4 to +4.
Usually it's common to use -1, 0 and +1 to create three exposures; one normal, one at -1 to show detail in the highlights, and one at +1 to allow details in the shadows to be recorded.
Then load the three images into Photomatix and let it do the merging for you.

A tripod is recommended to guarantee there's no movement between the exposures.
 
andyroo1986 said:
Use a program like Photomatix to convert a RAW file into HDR for you. Very simple!
Click to expand...

Photomatix doesn't convert a RAW into an HDR, a RAW *IS* an HDR. Photomatix Tonemaps an HDR image into a bog standard 8Bit normal dynamic range JPG.
 
Kaouthia said:
Photomatix doesn't convert a RAW into an HDR, a RAW *IS* an HDR. Photomatix Tonemaps an HDR image into a bog standard 8Bit normal dynamic range JPG.
Click to expand...

LOL... Photomatix outputs 16bit tiff unless you chose lower quality jpeg.
 
Gordon Scott said:
LOL... Photomatix outputs 16bit tiff unless you chose lower quality jpeg.
Click to expand...

Yes, but most skip the whole TIFF thing so they can put their images on the web, at which point it's no longer an HDR. But still, the TIF file from a single RAW is still just a tonemapped RAW file in a higher bitspace. (16bpp instead of 12 or 14bpp).
 
Kaouthia said:
Photomatix doesn't convert a RAW into an HDR, a RAW *IS* an HDR. Photomatix Tonemaps an HDR image into a bog standard 8Bit normal dynamic range JPG.
Click to expand...

I'm not sure this is right - if a RAW file was an HDR image then nobody would buy Photomatix etc, they would just shoot RAW for free.

HDR means that the image captures a greater dynamic range than a single exposure. This can be desirable if there is detail in both dark areas e.g. shadows and light areas e.g. the sky. Because cameras are not as good as the human eye, which can cope with this range and still pick out all the detail, a single photographic image will either be too dark in the shadow areas or too light in the bright areas.

You therefore need to capture a minimum of two identically composed images at different exposures and ideally three or more. Auto exposure bracketing (AEB) is a godsend for this, especially combined with continuous shooting. Set your camera to AEB and hold the shutter down while holding the camera still (or ideally use a tripod).

You then use Photmatix or similar (I use Dynamic-Photo HDR) to combine the images. You load in all of the images and then make sure that they are all lined up. You might need to move them around or rotate them a little so they are all stacked up neatly on top of each other. If you have used a tripod this will be a doddle, but it shouldn't be too difficult if they were handheld if you kept things steady.

Once all of the images are aligned, you press a button to create the HDR. You will then have an image that has detail in the dark, average and light areas. There are then further tools to play with to get the image as you like it.

You can then save it in whatever format you like. JPEGs can be HDR images - the filetype is irrelevant (except of course that JPEGs are as lossy with HDR images as they are with any other sort).

You can download trial versions of Photomatix, Dynamic-Photo HDR etc for free. They'll just put a watermark in your HDR images until you pay for the full version. You might as well download a couple of programs and see which (if any) you like.

Hope this helps.
 
J H B said:
HDR means that the image captures a greater dynamic range than a single exposure.
Click to expand...
Relative to JPG, RAW is HDR, although yes, and it's a dynamic ranger much higher than film ever was these days (although yes, still not technically HDR).

BUT, What people output from Photomatix, unless it acually is a .hdr file are not HDR. They are tonemapped to convert HDR into a lower dynamic range that are monitors are able to display or are printers are able to print.

Exactly how much dynamic range do you consider "high"? 3 exposures 1 stop apart? 5 exposures? 7? 9? 2 stops apart? 3? I've tonemapped 11 exposure images each 2 stops apart before now to get the complete contrast range of a scene. Some do it with only 3 jpg images and call it "HDR" (which combined contain less useful data than a single 14Bit RAW).

This is what allows people to create what is affectionately known as "pseudo HDR" (creating an HDR from a single RAW file). You're not creating an HDR from a single RAW file (at least not directly, it is an intermediary), you're tonemapping data that already exists in the file into a dynamic range that your monitor can display or your printer can print.

Even 16Bit TIFF files aren't higher dynamic range than JPGs. They still have the exact same white and black point (thus the same dynamic range), they just have more shades in between (0-65535 vs. 0-255 per channel - but 65535 and 255 are both the same amount of white, which isn't noticable on your monitor until you load it into photoshop and start adding curves and effects and see smoother transitions between shifting brightness and contrast).

Proper HDR files are 32Bit and are generally used by 3D software to provide realistic lighting simulations in scenes - These are generated by Photomatix behind the scenes (although you can tell it to save out the .hdr file too), and have a dynamic range far beyond that which can be displayed in JPG or TIF images, and far beyond the display technologies of pretty much any display or print device commonly available today) and that is tonemapped to a LOW dynamic range image (JPG or TIF).
 
Kaouthia said:
Exactly how much dynamic range do you consider "high"?
Click to expand...

You need as many as is appropriate to the dynamic range of the scene. If there are some very dark areas and some very light areas you may need several exposures to cover the whole range. Some scenes however are fairly evenly lit throughout and therefore don't really benefit from the technique, or at least not from loads of additional exposures. The consensus seems to be that if you are going to make an HDR image then the bare minimum number of exposures required is three.
 
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