The following presented Panorama Calculator is specially designed for the "Seitz" panorama head Roundshot VR Drive. The calculator takes into account the way to programming the Roundshot VR Drive. For a given horizontal field of view, the Panorama Calculator calculates the appropriate number of images to set this value on the VR Drive. Thereby the predefined horizontal overlap is guaranteed. The vertical parameters are certainly calculated to adjust the elevator with sufficient vertical overlap between each row. This depends on the selected vertical field of view and the vertical overlap.
 |
 |
The calculator calculates all relevant panorama parameters for cylindrical (MultiRow) and spherical panoramas. For spherical panoramas, a special algorithm reduces the number of images in rows successively, when the vertical angle is larger than a given angle away from the panorama horizon. Thereby the predefined horizontal overlap is guaranteed all the time. The calculations are based on the predefined horizontal/vertical panorama field of fiew, the predefined horizontal/vertical overlap between images and the camera model (sensor size) to capture the panorama. As an extra, the Panorama Calculator provides a bracketing calculator to make it easy to estimate the different shutter speeds in a bracket when shooting DRI / HDRI photos or panoramas.
If you like to find out more about the Roundshot VR Drive Panorama Calculator, just carry on reading. Additionally, the complete operator's manual, a short guide and more can be downloaded under the following link: Products / Download
Panorama VR Head: Roundshot VR Drive Panorama Set
Panorama Calculator for: Roundshot VR Drive Panorama Set
Panorama Calculator Menu Structure
Hyper focal distance and Depth of Field Calculator
The Panorama Calculator represented here, is developed for the operating system Windows from Microsoft
.
Good news for MAC
user! The Panorama Calculator should work also on a MAC with Intel CPU and installed "Wine". More details under the following link:
Which are the calculated parameters?
- Calculates all important parameters to position the panorama head for each image
- Calcultes for a first calculation the horizontal and vertical overlaps with the predefined values 25% resp. 30%. The overlap input values can be changed to optimize a calculated result
- Depending on the camera model and focal length used, the Calculator supports over a span of 180° up to 21 vertical rows and horizontal columns up to the limitation of the Roundshot VR Drive (72 Columns over 360° or the selected panorama Field of View (FoV) in 45° steps)
Which are the parameter inputs?
- Camera model with its parameters (to set once for a specific camera)
- Not too tight calculated horizontal and vertical panorama Field of View (FoV) in degrees [°]
- Focal length of the used lens in millimeters [mm]
- Overlap between columns and rows in degrees [°]
- Horizon shift in degr. [°] to adapt the real horizon to the Panorama vertical center
Further characteristics:
- Calculation for Portrait and Landscape format
- After an automatic calculation it is possible to change the number of columns and/or rows and recalculating the parameters in manual mode.
- Includes an editable camera parameter database for up to 100 camera models. In the database not included camera models can be updated easily by the user itself
- Generates script files to control the panorama head out in the field
- Helpful hints in the Status line
- Helpful hints when hovering the mouse over an input or output mask
- The Panorama Calculator includes also a Bracketing Calculator
Which are the calculated parameters?
Which are the parameter inputs?
- Camera model with its parameters (to set once for a specific camera)
- Focal length of the used lens in millimeters [mm]
- Indivual minimal overlap between columns and rows in degrees [°]
- Three different calculation modes to calculate the vertical parameters:
- Caculation in fix step sizes
- Optimize Nadir/Zenith
- Take into account dead angle
Further characteristics:
- Fix aperture and shutter speed for the brightest details in the panorama.
- Number of images pro camera position
- EV (Evaluation Value) step size selectable out of 6 values:
½ EV step size: ½, 1, 1½, 2, 2½ and 3
or
1/3 EV step size: 1/3, 2/3, 1, 1 1/3, 1 2/3 and 2
Calculates shutter speeds for dark to bright areas of the panorama in max. 15 steps
Note: Most SLR cameras supporting an autumatic bracketing mode. The Bracketing Calculator supports 15 images in a bracket. Normally SLR cameras are supporting just 3 images in a bracket.
The Roundshot VR Drive controls a series of single shots of a conventional digital camera. The electronics unit of the Roundshot VR Drive controls rotation times, the number of single shots in a pre-defined circle as well as bracketing functions (multiple exposures). The automatic light metering and focusing are not controlled by the Roundshot VR Drive but rather by the digital camera. The series of single shots are stitch with special software to create the panorama.
The digital camera is mounted on the universal holder and is connected to the Roundshot VR Drive engine with an electronic release cable.
Roundshot VR Drive Panorama Set |
The Panorama Head has buttons and a LCD-Display to program the motorized horizontal Roundshot VR Drive. This gives the photographer full automatic control over the horizontal positioning of the Panorama Head. More details about the Roundshot VR Drive is explained in the <Roundshot VR Drive Instruction Manual>
The Roundshot VR Drive Panorama Set Panorama Calculator is available now. This Calculator supports both MultiRow and Spherical panoramas. For MultiRow panoramas, the Portrait and in Landscape format is available. The Spherical Panorama Calculator supports the Portrait format only. The MultiRow Panorama Calculators is supporting an Auto and Manual calculation Mode. This allows the photographer to change the number of columns (H) and rows (V) after an "Auto Calc". A following new calculation will change the output parameter as follows:
When the calculated overlaps are too small or when other input parameters does not obtain save panorama output parameters, a warning with a help text will be displayed in the status line.
Furthermore, a bracketing Calculator supports the photographer to calculate for each camera position the shutter speeds. In the cameras bracketing mode, for each camera position the camera takes normally three images with different shutter speeds. Special programs on the market as PTGUI Pro, Photomatix ... are available to blend the images to a single HDR (High Dynamic Range) image.
MultiRow Panorama Workflow
In the preparation phase, the photographer should define the horizontal AoV in the input field of the Panorama Calculator. The AoV is selectable in 45° steps. When the panorama has to be in high resolution, more than one row will be necessary to cover the desired vertical AoV. In this case, the vertical AoV is also a very important input parameter. The next step, if not done already, is to define in the "Sensor Database" the camera planned to use for the panorama. This sets the sensor dimensions and the horizontal and vertical pixel counts necessary to calculate the panorama parameters. As next, enter the focal length of the lens, without any crop factors, in the input field. - That is it - A click on the button "Auto Calc" or "Manual Calc" will calculate all panorama parameters including the one’s needed for the Poundshot VR Drive which are:
When entering those two parameters to the Roundshot VR Drive, the Drive is sequentially positioning the head to the horizontal positions with the step size calculated in the Panorama Calculator. In the "Auto Cal" Mode, the Panorama Calculator guarantees a horizontal overlap between single images (columns) of at least 30% and a vertical overlap of exactly 30%.
Furthermore, the Panorama Calculator calculates the vertical elevation values to adjust the vertical rotator bracket for each row. At the end of the calculation process, the parameters can be saved in a <MultiRow script file> to disk for later printout. This is very helpful when tacking a panorama out in the field.
Spherical Panorama Workflow
The workflow for MultiRow Panoramas is quite easy - but the workflow for Spherical Panoramas another step easier. When the correct camera model is selected in the "Camera Parameter” database, only the focal length without any cropping factor has to be set in the input field of the Panorama Calculator. - That is it - A click on the button "Auto Calc" or "Manual Calc" will calculate all panorama parameters including the one’s needed for the Roundshot VR Drive which are:
When entering these tow parameters to the VR Drive, the Drive will sequentially positioning the head to the horizontal positions with the step size calculated in the Panorama Calculator. In the "Auto Cal" Mode, the Panorama Calculator guarantees a horizontal overlap between single images (columns) of at least 25% and a vertical overlap of exactly 20% as default.
Furthermore, the Panorama Calculator calculates the vertical elevation values to adjust the vertical rotation bracket for each row. At the end of the calculation process, the parameters can be saved in a <Spherical script file> to disk for later printout. This is very helpful when taking a panorama out in the field.
The following menu structure of the Panorama Calculator should describe the different menus in more detail. This gives you an impression how easy and fast the Panorama Calculator calculates the parameters for specific equipment.
The Panorama Calculator will be available and delivered by e-mail with a detailed documentation.
|
|
For more details click on a calculator in the vertical menu bar. |
For more details click on the "Select" button.
|
The picture above shows the menu structure of the Panorama Calculator. A click on one of the light gray submenu will jump to a high-resolution image and a more detailed description of the menu. The Panorama Calculator is bi language, German and English. The selection of language is done by shortcuts or by selecting in the menu “Extra”.
The MultiRow Panorama Calculator got an input and an output field. Before calculation, the default input field values should be changed with parameters they meet your need. In the output fields, important horizontal and vertical parameters are displayed to position the panorama head for a specific panorama. The activation buttons and the status line are placed at the bottom of the Panorama Calculator. After a calculation, warnings will be displayed in the status line, if necessary.
After starting the MultiRow Panorama Calculator, check the indicated “Camera Model” in the input field. If not done already, it is easy to choose the correct camera model in the “Camera Parameter” database via the “Select” button.
Before starting a calculation, enter the following parameters into the input masks:
After calculating in “Auto Portrait” or “Auto Landscape” mode, the "Manual Portrait" or "Manual Landscape" mode allows the photographer to change the “No. of images (H)” and “No. of images (V)” to optimize the "Auto" calculated result.
The button “Script Type” opens the save dialog to save the script to the hard disk.
A new feature of the Panorama Calculator is the ability to calculate individual number of images for each row. The more a row is placed away from the horizon to Nadir or Zenith, the less images are necessary for a specific row. Specially for high resolution spherical panoramas, the amount of images be taken for the whole panorama can be reduced, sometimes dramatically.
When removing the tick "Optimizer for no. of Columns in Rows", the Panorama Calculator calculates the horizontal parameters for the horizontal plain. These parameters are used also for the rest of the rows.
The Spherical Panorama Calculator got an input and two output fields. First, override the default input field values with parameters, which meet your needs. To position the panorama head for a specific panorama, important horizontal and vertical parameters are displayed in the output fields. The activation buttons and the status lines are placed at the bottom of the Panorama Calculator. After a calculation, warnings will be displayed in the status line, if necessary.
After starting the Spherical Panorama Calculator, check the indicated “Camera Model” in the input field. When a wrong “Camera Model” is set, activate the “Select” button and choose the correct model in the database. With the correct “Camera Model” and the “Dead Angle” of the panorama head set, just one parameter is necessary to start a first calculation. The parameter is the focal length of the lens in millimeter. In the input mask, enter the “Focal Length”, which is engraved on the lens, without any factor. For a first calculation, the “Min. overlaps” are not changed.
A click on the button “Auto Calc” calculates the parameter necessary to position the panorama head for each image in the panorama. Considering the rounding of the number of columns, the horizontal overlaps between columns complies as close as possible the predefined percentage in the input field. The vertical overlaps between adjoining rows are at least 25%.
To calculate the position of the rows (vertical), three calculation modes are available:
In this mode, the positions of the rows are calculated to get between ±90° fix step sizes. The image at +90° is known as image in Zenith and the image at -90° is known as the image in Nadir.
This calculation mode has the disadvantage, while turning the panorama head fully from 0° to 360°, the top row is overlapping the image in Zenith also on the length side. In this case an overlap of at least 25% can’t be guaranteed. The reason why this calculation mode is normally used by most of the panorama photographers because – it is simplicity to calculate.
This calculation mode eliminates the disadvantage of the mode with fix step sizes. This is done by guarantee at least 25% overlap during the top row overlaps the length side of the image in Zenith. The consequence is slightly reduced overlaps between the rows.
The third and last calculation mode takes into account the dead angle caused by the panorama head in Nadir. In the calculation modes mentioned before it is possible that the lowest row to Nadir moves into the dead angle of the panorama head. In this case the photographer will capture image information which can't be used for the panorama.
This calculation mode moves the lowest row to Nadir out of the dead angle and allocating the rest of the rows to get equal overlaps between rows. Between Zenith and the top row an overlap of 25% is guaranteed as mentioned for calculation mode “Optimize Zenith/Nadir”. Possibly the overlap between the lowest row and Nadir wouldn’t reach the 25%.
After a calculation “Auto Calc”, sometimes photographers likes to expand the horizontal or vertical overlaps. This can be done by increasing the values in the input masks “Min. Overlap Columns (H)” and “Min. Overlap Rows (H)”. When pressing the button “Auto Calc” again, the calculation takes into account the new overlap values.
The button “Save Script” opens the save dialog to save the script to the hard disk.
Short introduction
In HDRI (High Dynamic Range Imaging) panorama photography “Bracketing” technique is used to master high dynamic range. That means a whole set of images is taken for a specific camera position. Each image in a “Bracketing” set should be taken with different shutter speeds. Between the images in the set a fix EV-step size is used. As documented in the following image it is a common practice to use odd-numbered values of images in a “Bracketing” set. So each “Bracketing” set has its centre image and symmetrical allocated the rest of the images as implemented in most digital SLR cameras. During the whole panorama shooting the diaphragm should not be change to achieve constant depth of field in the panorama. As an example an EV-step size value of 1 complies with a change of the diaphragm form 5.6 to 8 or vs. 8 to 5.6.
For a photographer it is not easy to estimate an appropriate number of images and the value for the EV-step sizes between the images in a “Bracketing” set. The goal using Bracketing is to ensure to cover the whole exposure dynamic range of the entire panorama. When during the shooting moving objects as vehicles or walking people are expected, it is recommended to choose a convenient aperture and EV-step size to obtain appropriate shutter speed for the low end of the dynamic range (the dark areas). When the shutter speed is too slow, moving elements will not be sharp.
As a basic principle all images should be taken in manual camera mode, whether the panorama is taken with or without “Bracketing”. Thereby both, aperture and focus stays in manual mode during the whole shooting. As mentioned above, between two images in a “Bracketing” set, the shutter speed is varying in steps of the selected EV-step size. This is necessary to get correct exposure for the full dynamic range of the panorama. When the panorama is taken without Bracketing, the shutter speed should be left unchanged too. Furthermore, the white balance (WB) should be a fix value or selected by the symbols (sun, clouds ...). The same is appropriate for the ISO value. Focus is initially adjusted with auto focus or manually. During the panorama shooting, the focus should be readjusted in exceptional cases only.
A very helpful tool to estimate a convenient depth of field is downloadable under the following link on the web site of Bon Atkins.
http://www.bobatkins.com/photography/technical/depth_of_field_calc.html
First, it is important to measure the exposure for the brightest area in the panorama. When the luminance values for red, green and blue (RGB) exceed 250,250,250 the bright details are lost forever. Not even Photoshop and Co. will help to bring them back. When aperture and shutter speed are not changed during a panorama shooting the bright areas are exposed correctly but not the dark areas. In this case details in the dark areas are missing. Brightening up these areas are very limited. The only way out is HDRI (High Dynamic Range Imaging) or DRI.
The Panorama Calculator offers support for HDRI
With the following parameters, the Bracketing Calculator can calculate for a specific camera position up to nine shutter speeds.
To estimate the lower border (dark areas) of the panorama dynamic range a second exposure measuring should be done. The measurement delivers the reference shutter speed for the dark areas. Remember, the aperture is still unchanged as used for the upper dynamic range border. The next step is to find out a convenient number of images and EV-step size to achieve the measured shutter speed for the dark areas. This is done by vary these values until the longest shutter speed is as close as possible to the one was measured. The cameras histogram is very helpful to evaluate the correct exposure for the upper and lower end of the panoramas dynamic range.
After the shooting, programs like Photomatix, PTGui Pro, Photoshop ... are able to fit the single or even a Bracketing sets of an already stitched panorama to a HDRI panorama.
An Example
Let say the measured shutter speed and diaphragm for the bright areas, the upper limit of the panorama dynamic range are 1/500” respectively f/8. As mentioned above the aperture stays unchanged during the whole panorama shooting. This is necessary to secure constant depth of field for each image. For the second measured shutter speed and the still unchanged diaphragm f/8 we get 1/15”.
To avoid fuzziness from moving elements, it is important to take care, the shutter speed at the lower end of the dynamic range (dark areas) is not too long. If so, just use a higher shutter speed when measuring the bright areas in the panorama. Simultaneously the aperture will be decreased and ends in a smaller depth of field.
First calculation
First, we set the shutter speed and diaphragm, measured for the bright areas, in the Panorama Calculator by using up/down arrows. Next we set a trial number of images, used for each camera position, let say 5. Finally the EV-step size to 2 f-stops. With these presets the first calculation should be done.
The calculated shutter speed for the lower end of the dynamic range shows the value 0.5” and is far away from the measured 1/15”. With this shutter speed, the dark areas would be very overexposed – too bright.
To achieve a correct exposure for the dark areas we have two possibilities either we decrement the number of images or the EV-step size.
Second calculation
For the second shutter speeds calculation we use the following input parameters: diaphragm = 8, shutter speed = 1/500”, number of images = 5 and EV-step size = 1 1/3. The result for the shutter speed for the dark areas is 1/13”. This exposure is just 1/3 f-stop overexposed - it is perfect.
A result something like that 1/30" we can get when the EV-Step size is reduced from 1 1/3 to 2/3 and the no. of pic/position is increased from 5 to 7. In this case, the exposure for the dark areas will be 1 1/3 EV-Step underexposed. For a high panorama dynamic range I would prefer calculation with the 7 images.
As seen in the example above, the by varying the EV-step size and/or the number of images per camera position, the shutter speeds for the “Bracketing” set are displayed after activating the “Calculate” button. The higher the dynamic range of a panorama the more images are needed for a Bracketing set. In other words, to get enough images and convenient shutter speeds for a specific dynamic range, the number of images and the EV-step size should be balanced carefully. This will guarantee correct shutter speed for the dark areas.
Right now just minor SLR cameras providing a “Bracketing” function with more than 3 images per camera position. Most SLR cameras of them provide 3 bracket. Normally the EV-step size can be selected in 1/3, 1/2, 1 and 2 steps in between EV = +/-1/3 and EV = +/-2. An exception is a Nikon model in the upper price segment, which supports 5 and 9 images per camera position. With the Canon 1Ds Mark II a special software allows to program user specific bracketing.
I use this program for my Canon's and I can recommend it.
For further information about HDRI (High Dynamic Range Imaging) I recommend “The HDRI Handbook” from Christian Bloch. It describes all the details and what we can expect in the future in HDRI in a fascinating way.
ISBN: 9781933952055
ISBN-10: 1933952059
In the database is space for 100 different cameras with its specific parameters. Values for the sensor size in millimeters and the number of pixels are documented in the manufacturer use manual. If not – they are also published in the World Wide Web. The dead angle, caused by the panorama head in the Nadir, is easy to estimate by the photographer him or herself. In the detailed documentation of the Panorama Calculator, a straightforward procedure guides the photographer through this task. Different focal length may also have different values for the dead angle of the panorama head. For MultiRow panoramas, which have no objects close in front of the lens there, there is no need to use the dead angle for calculations.
In the first row of the “Camera Parameter” database, the default parameters are placed and will be used for calculations. Any time the Panorama Calculator is started, automatically the default parameters stand in the first row of the “Camera Parameter” database. It is easy to place a camera to the first row as the default camera. This is done by overwriting the values in the first row with the new camera parameters and by pressing the button “Save Database” and quit the database by activating the 
. button.
If your camera is already in the database but not in the first row, just “Select” on the bottom left the correct number and press the button “Save changed parameters”. As long as you do not change anything, your camera is the default camera in the first row.
An other program is the Hyper focal distance and Depth of Field Calculator. For high resolution panoramas, photographed with long focal length, Hyper focal distance and Depth of Field plays an important role. In panorama photography, normally Depth of Field can't be large enough. This can be achieved when focusing the lens to the Hyper focal distance. What is the Hyper focal distance and what are the parameters takes influence? The Hyper focal distance depends on the following physical values:
When shooting a panorama, especially high resolution panoramas, normally the photographer likes to get as much as possible sharp in the resulting stitched image. This can be reached when focusing to the so called “Hyper focal Distance”. When do so, the images will be sharp from half of the hyper focal distance to infinitely. This statement is correct when a single image is enlarged not more than 10” x 8” and viewed at a distance not closer than 1 foot.
While the button “Generate Script” is pressed the save dialog opens to save the script file. The script file includes in a nice presentation of all calculated parameters. The script file supports the photographer at the place he likes to take the panorama. Two examples of a script file can be downloaded under the following links: <Script file MultiRow Panorama> <Script file Spherical Panorama>
