Artizen >> Tutorials >> Creating HDR images - Oct 16 2008

     To begin this tutorial it is assumed that you have a basic understanding of what HDR images are. If that is not the case, please read What is HDR tutorial. In addition, for this tutorial you need several photographs of the same image at different exposures (preferably captured using a tripod). 

The "Merge to HDR" tool is used to merge multi photograph exposures into a single photo called HDR. So the first step is selecting the photos you want to merge together, once you have done this there are 3 options to select from. The top 2 determine what sort of auto alignment you would like to perform on your photos. If a tripod was used you might not want to have either selected, but in most cases you would only select the "Automatically align source photos". The bottom option speeds workflow when a tripod was used and the chance of misalignment is small, by bypassing the manual alignment window.

Photo List

If you choose to make additional manual corrections and wish to see how well the photos have been aligned, you select any photo other than the first photo on the list which is considered the master photo (the photo by which all other photos are aligned to).

To see all the information related to each image you can scroll the image list to the right and see, fstop, exposure time, (x,y,a) alignment as well as image ranking or select each file individually.

(X, Y, A) Precession Alignment & Auto Alignment

The X, Y and A alignment options allows the users to align the images to a master image before applying the hdr merge. The first image of the list is always the master image, and the order of the list presented has no effect as everything is ordered during the merging process. 

Checkbox 

The Checkbox option beside each photo allows users to unselect any issues they don't like or can't align properly before merging to the final image.

Freehand

The Freehand option was included in order to enabled users to align images in the same manner that you would move layers around in Artizen. To utilize this option you require to check off the Freehand checkbox located to the right of the Alignment Tools title. Once finished, this box can simply be unchecked.

Create HDR File

Since creating an HDR file is unnecessary unless it's needed for a specific purpose then having this option unchecked will make the workflow faster as well as save space on the Hard Drive.

Fix Black Spots

Sometimes during the merging process if there are not enough exposures, black spots will appear. This is part of the merging process trying to control which data is used for the final result. To address this Artizen has added the Fix Black Spots option which attempt to reduce this issue.

Aligning an image is done through selecting any image other than the first on the list, which is considered the Master. All images below the Master are aligned to the Master image. Once selected the Alignment Preview Window gets updated with the new layer. To correct any misalignment, scrolling the up/down arrows of x Shift and y Shift options allows for pixel accurate correction. To make this process as simple and precise as possible, users can move the image position, zoom in and out and adjust the opacity of the image layers to allow for easier comparison. The opacity has no effect on the final result and is only used to help with alignment.

Multi Photo Merging Process

  1. Goto HDR's | Generate HDR Image... menu option.

  2. Once the "Merge to HDR" tool is open, click the Browse... button.

  3. Select the files you want to use to create your hdr image.

  4. If you did not use a tripod or feel that your photo maybe misaligned slightly, then click the Automatically align source photos button. 

  5. Click Apply button.

  6. If you feel the misalignment was significant enough, and your image requires additional manual correction, then select each photo one by one and using the Hand, Zoom, and Opacity tools verify each photo's alignment. If you believe there maybe a misalignment, adjust the x Shift and y Shift values until the layer is properly positioned. This information is preserved in the Image List, which can be seen by scrolling the Image List to the right. 

  7. Click the Apply button to begin the merging process.

  8. Once your merging operation is completed, Artizen will ask if you want to Tone Map your image now. If additional editing is required before tone mapping simply select "No" and you will be able to tone map your image anytime using the HDR's | Tone Mapping... menu option. Once you are happy with your results you can save the image in any format available in Artizen, either HDR or LDR formats.

Single File Tone Mapping

If you want to tone map a single jpg or raw file, simply load your photo into Artizen and not into the Merge to HDR tool and then proceed directly to the HDR's | Tone Mapping... menu option and Artizen will do the rest for you.

  1. Open Artizen.

  2. Goto File | Open... menu option.

  3. Once file has been loaded goto HDR's | Tone Mapping... menu option.

  4. If the file was one of the hdr file formats the Tone Mapping preview tool will automatically load. If the file was any other file format like a camera RAW or jpg, a popup option will load asking if you would like Artizen to prepare this file by converting it into the hdr color space which is required for tone mapping. Once you click Yes, Artizen will then load the Tone Mapping window.

To learn more about tone mapping you image go to our Tone Mapping tutorial.

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