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SkySafari 5 Plus | How to Show Field of View (Using DSLR Only)

 

IN Sky Safari 5 Plus, how do I show the field of view, if I am NOT using a telescope, but instead using a DSLR camera (Canon) and a telephoto lens? I'm using an Ipad.
Thanks

 

13 comments

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    Keiron Smith

    Hi Dan,

    What is the DSLR mounted on?

    Thanks!

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    Keiron Smith

    Hi Dan, 

    I'm assuming you want to use SkySafari to control your EQ5 mount even though it has only the DSLR mounted on it. 

    So...

    In Settings >>> SetUp >>> ScopeType >>> Orion Atlas (this only applies if you have a telescope control solution; i.e. SkyFi 3)

    In Settings >>> Display >>> Fields of View >>> Custom Field of View <<< define a FOV that matches your DSLR

    In Settings >>> Display >>> Fields of View >>> Field of View Display Options >>> Show Even if Not Connected to Telescope <<< checked ON.

    Now...

    You can connect and control your mount (if you have a telescope control solution) and show the FOV for your DSLR.

    Thanks!

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    Dan Bjarnason

    hi kelon ...

    im not trying to control my mount with sky safari ... what i want to do is for sky safari show my what the field of view will be if i  have my canon 70D dslr camera, with a 300 mm lens, mounted on a tripod. i want some representation of what the camera will see.

    i know how to do it for telescopes and eyepieces, but i cant figure out how to do it with just a camera and a lens.

    thanks

    dan

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    Keiron Smith

    Hi Dan, 

    What is the FOV of your 300mm lens attached to the Canon 70D?

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    Dan Bjarnason

    hi again  jeiron

    i havent been able ot figure that out. and canon's web site is no help. sorry.

    dan

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    Mario Wolczko
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    Dan Bjarnason

    great mario. many thanks.

     

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    Keiron Smith

    Thanks, Mario!

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    John Fisanotti

    Hi Dan:

    I've done it and it is not that complicated.  Besides knowing the focal length of the lenses you intend to use with the camera, you also need to know the size of the camera's sensor.  I looked it up on-line and a Canon 70D has a sensor which is 22.5mm x 15mm.

    Now go to Settings>Equipment>Add Camera.  There are five fields to fill out but you only need to fill out the first three:  In your case, "Camera Name" would of course be Canon 70D, "Sensor Width" would be 22.5 and "Sensor Height" would be 15.  You can leave the two "Offset" fields at zero (0).

    Now tap "Equipment" to back out of that and then tap "Add Telescope".  I add everyone of my camera lenses as if it were a telescope.  There are three fields to fill out but you only need to fill out two.  Under "Scope Name" I list the lens (e.g. 135 mm f/2.0), you can leave the "Aperture" field at zero (0), and in the "Focal Length" field enter the focal length of the lens (e.g. 135).  Do this for every lens you intend to use for astro-photography.

    Now that you have entered the parameters of your equipment you can select them to display the field of view:  Go to Settings>Display>Fields of View and then select the camera and the lens combination you plan to use and select "Show Even If Not Connected to Telescope".  That should do it.  Also notice the "Field Rotation Angle", which is right under "Show Even If Not Connected to Telescope".  Because the sensor is a rectangle, your field of view is a rectangle and you can use this to rotate the box to figure out which orientation of the camera will frame the subject best

    I hope this helps.

    John Fisanotti

     

     

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    Dan Bjarnason

    wonderful. thanks john.

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    Tim Campbell

    The lens and camera have to be added separately.  

    First add the lens... go into "Settings" -> "Equipment" then in the "Telescopes" section tap "Add Telescope" (even though it's a lens).

    It will ask you for three things:

    1)  A name - any name you want (e.g. "300mm f/5.6 lens" for example)

    2)  The aperture ... you'll do a quick bit of math.... the aperture (in millimeters) is simply the focal length of the lens (e.g. 300mm) divided by the focal ratio (e.g. 5.6).  So in this example, 300 / 5. 6 = 53.57.  I'd round that to 53.6 and key that value in.

    3)  The focal length (e.g. 300mm)

    With the lens in the database (as a telescope) you also have to add your camera.

     

    Go into "Settings" -> "Equipment" and in the "Cameras" section tap "Add Camera"

    The camera wants to know 5 pieces of information.

    1)  The name ... any name you want (e.g. I have a "Canon 60Da" on my list)

    2)  The sensor width and (this is important) this must be entered in MILLIMETERS (some users confuse this for the camera resolution... it wants to know the physical dimensions of the image sensor to calculate the field of view).  My particular camera has a 22.0 mm wide camera sensor.

    3)  The sensor height (again, in millimeters).  Mine is entered as 15mm.

    4)  The sensor x-offset in millimeters (typically this is just 0 - more on this in a moment)

    5)  The sensor y-offset in millimeters (also typically just 0).

    About those "offsets"... some telescope imaging setups have both an "imaging" camera and a "guiding" camera operating at the same time and they may use a technique called "off-axis guiding".  In that setup, the guide adapter allows two cameras to connect to the same telescope... one camera (typically the main imaging camera) is at the back and has the largest field of view through the center of the scope.  But the adapter has a tiny prism on the edge called a pick-off mirror... and this bounces light out at a 90º angle to a second camera (the guide-camera).  The field of view for this camera isn't in the center of the telescope's optical axis... it's off to the side.  So this "x" and "y" offset data allows you to position the field of view of the camera so that it isn't actually in the center of the telescope's optical axis -- it's offset by some amount (so that two different cameras can look through the same telescope at the same time.)

    If you aren't doing this type of work, then just enter the "x" and "y" values as 0's (which means the center of the camera's field of view in in the center of the telescope's optical axis.)

     

    Now you've got the equipment entered... but no field of view.

    Go into "Settings" -> "Display" and you'll notice Sky Safari offers 5 different "Fields of View" which you can configure on/off.  

    Tap a row near the right edge (where you see the ">" arrow) and this will let you configure which telescope & camera (or telescope & eyepiece) combination will be used for that field of view.    

    When you're in that section, you'll see a couple of lists... first is a list of telescopes, binoculars and finders... you should see your new camera lens on that list.  Tap it to select it.   You should see a checkmark next to your selected piece of equipment.

    Scroll down further and you'll the list of "eyepieces & cameras".  You should see the camera you just added on that list.  Tap it to select the row and confirm that you get a checkmark on the row indicating it has been selected.

    At the top of the panel, tap "< Display" to save your configuration and return to the previous menu (if you tap "Done" then it will save but return to the main Sky Safari display (you'll have to go back into "Settings" again).

     

    Now you should see your newly configured Display choice... but it's likely toggled off.  Just tap the toggle to turn it on.

    Before you tap "Done", gaze down to the bottom of the screen and notice there's a setting for "Field Rotation Angle".    Tap that and it'll take you to a preview window which shows the current area of the sky, with a slider along the bottom that lets you rotate your field of view.  

     

     

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    Dan Bjarnason

    thanks tim. much appreciated.

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    Dan Bjarnason

    thanks everyone. all the help is much appreciated. i get it now. 

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