06 - Lens Calibration Part 1¶
▶ 06 - Lens Calibration Part 1 — Watch on YouTube
[Music] [Music] in order to correctly use our target in order to correctly use our target in order to correctly use our target tracking and enable us to focus follows tracking and enable us to focus follows tracking and enable us to focus follows target accurately we need to calibrate target accurately we need to calibrate target accurately we need to calibrate our focus axis at the moment our focus our focus axis at the moment our focus our focus axis at the moment our focus axis is merely displaying a number at axis is merely displaying a number at axis is merely displaying a number at the top that is due to the scale factor the top that is due to the scale factor the top that is due to the scale factor involved which happens to be that at the involved which happens to be that at the involved which happens to be that at the moment that number means nothing but moment that number means nothing but moment that number means nothing but will be used to create the correct will be used to create the correct will be used to create the correct scaling factor in order to set up this scaling factor in order to set up this scaling factor in order to set up this lens I'm going to go to the lens setup lens I'm going to go to the lens setup lens I'm going to go to the lens setup and choose an empty lens this screen and choose an empty lens this screen and choose an empty lens this screen shows the main things that need to be shows the main things that need to be shows the main things that need to be set up in order to calibrate this lens set up in order to calibrate this lens set up in order to calibrate this lens to work on this camera with that motor I'm going to look first of all at this I'm going to look first of all at this box that says customize focus customize box that says customize focus customize box that says customize focus customize focus uses the information in a library focus uses the information in a library focus uses the information in a library file here to write a focus axis when a file here to write a focus axis when a file here to write a focus axis when a given lens is loaded at the moment this given lens is loaded at the moment this given lens is loaded at the moment this information is garbage so customize information is garbage so customize information is garbage so customize focus is unchecked so that the garbage focus is unchecked so that the garbage focus is unchecked so that the garbage in here is not written on to the focus in here is not written on to the focus in here is not written on to the focus axis I'm going to first of all give the axis I'm going to first of all give the axis I'm going to first of all give the lens a name and the lens name I'm giving it is re and the lens name I'm giving it is re ultra Prime 60 millimeter because that ultra Prime 60 millimeter because that ultra Prime 60 millimeter because that is the lens that I have mounted on the is the lens that I have mounted on the is the lens that I have mounted on the camera the focal length of that lens is camera the focal length of that lens is camera the focal length of that lens is 50 millimeters because this is a good 50 millimeters because this is a good 50 millimeters because this is a good lens I know that that is likely to be lens I know that that is likely to be lens I know that that is likely to be true some poorer mentees may say they true some poorer mentees may say they true some poorer mentees may say they are 50 millimeters but they may well be are 50 millimeters but they may well be are 50 millimeters but they may well be 49 or 51 or some other value this 49 or 51 or some other value this 49 or 51 or some other value this particular lens mounted on this camera particular lens mounted on this camera particular lens mounted on this camera is a lens that moves in order to focus is a lens that moves in order to focus is a lens that moves in order to focus if I had a fixed lens and moved my if I had a fixed lens and moved my if I had a fixed lens and moved my camera back in order to focus my legs camera back in order to focus my legs camera back in order to focus my legs would be stationary in this case my lens would be stationary in this case my lens would be stationary in this case my lens move in order to focus on I'm gonna move in order to focus on I'm gonna move in order to focus on I'm gonna check the box lens moves now I need to check the box lens moves now I need to check the box lens moves now I need to put something into this box here which put something into this box here which put something into this box here which is called lens factor if I had a perfect is called lens factor if I had a perfect is called lens factor if I had a perfect lens it would be infinitely thin plane lens it would be infinitely thin plane lens it would be infinitely thin plane and the two focal points would be 100 and the two focal points would be 100 and the two focal points would be 100 millimeters apart for a 50 millimeter millimeters apart for a 50 millimeter millimeters apart for a 50 millimeter lens the lens we're using is in fact a lens the lens we're using is in fact a lens the lens we're using is in fact a lump of glass metal and plastic and it lump of glass metal and plastic and it lump of glass metal and plastic and it is possible that the focal points are is possible that the focal points are is possible that the focal points are more than or less than 100 millimeters more than or less than 100 millimeters more than or less than 100 millimeters apart this difference or fatness of a apart this difference or fatness of a apart this difference or fatness of a real world lens is called lens factor we real world lens is called lens factor we real world lens is called lens factor we don't know what the lens factor of this don't know what the lens factor of this don't know what the lens factor of this lens is and re or a Zeiss who lens is and re or a Zeiss who lens is and re or a Zeiss who manufactured the lens probably wouldn't manufactured the lens probably wouldn't manufactured the lens probably wouldn't tell us the calculation is done as part tell us the calculation is done as part tell us the calculation is done as part of this function but in order to do the of this function but in order to do the of this function but in order to do the calculation we have to put a value in to calculation we have to put a value in to calculation we have to put a value in to work with so I'm going to put 10 work with so I'm going to put 10 work with so I'm going to put 10 centimeters into here or 0.1 centimeters into here or 0.1 centimeters into here or 0.1 meters so my lens factor I have guessed meters so my lens factor I have guessed meters so my lens factor I have guessed at 10 centimeters I can now go to open at 10 centimeters I can now go to open at 10 centimeters I can now go to open this box call calibrate focus in this this box call calibrate focus in this this box call calibrate focus in this calibrate focus box I have three target calibrate focus box I have three target calibrate focus box I have three target distances and three focus positions distances and three focus positions distances and three focus positions these are readings from the motor which these are readings from the motor which these are readings from the motor which is English with the gears on the lens is English with the gears on the lens is English with the gears on the lens these are the target distances as marked these are the target distances as marked these are the target distances as marked on the marks on the lens in order to get on the marks on the lens in order to get on the marks on the lens in order to get the first target distance I have to be the first target distance I have to be the first target distance I have to be at infinity and in fact what I'm going at infinity and in fact what I'm going at infinity and in fact what I'm going to do is I'm going to turn off my focus to do is I'm going to turn off my focus to do is I'm going to turn off my focus axis so I can back drive the motor and I axis so I can back drive the motor and I axis so I can back drive the motor and I am now going to put them wing on am now going to put them wing on am now going to put them wing on infinity by physically moving the lens I have now put the lens on infinity but have now put the lens on infinity but the focus axis doesn't read zero so what the focus axis doesn't read zero so what the focus axis doesn't read zero so what I'm going to do now is I'm going to I'm going to do now is I'm going to I'm going to do now is I'm going to directly zero the lens at infinity this directly zero the lens at infinity this directly zero the lens at infinity this gives me the end of my travel and the gives me the end of my travel and the gives me the end of my travel and the zero reference or home position for my zero reference or home position for my zero reference or home position for my focus axis because that is effectively focus axis because that is effectively focus axis because that is effectively infinity there's no numbers there my infinity there's no numbers there my infinity there's no numbers there my focus position for this read from the focus position for this read from the focus position for this read from the motor is left click right click store motor is left click right click store motor is left click right click store zero and now going to go to a point zero and now going to go to a point zero and now going to go to a point halfway along the travel of the motor halfway along the travel of the motor halfway along the travel of the motor the lens turns around and is a the lens turns around and is a the lens turns around and is a logarithmic scale that I'm going to go logarithmic scale that I'm going to go logarithmic scale that I'm going to go halfway around the travel of the motor halfway around the travel of the motor halfway around the travel of the motor in order to find a mid position for my in order to find a mid position for my in order to find a mid position for my curve curve curve I have gone to four feet which on this I have gone to four feet which on this I have gone to four feet which on this lens is halfway around my travel four lens is halfway around my travel four lens is halfway around my travel four feet corresponds to 122 centimeters on feet corresponds to 122 centimeters on feet corresponds to 122 centimeters on this scale only we are measuring the this scale only we are measuring the this scale only we are measuring the distance in centimeters I'm at 4 feet I distance in centimeters I'm at 4 feet I distance in centimeters I'm at 4 feet I have entered that in my target distance have entered that in my target distance have entered that in my target distance just here I now go left click right just here I now go left click right just here I now go left click right click store and I have a value there click store and I have a value there click store and I have a value there that is halfway around my travel based that is halfway around my travel based that is halfway around my travel based upon the present lens scaling it's upon the present lens scaling it's upon the present lens scaling it's notable but that is a positive number I notable but that is a positive number I notable but that is a positive number I need that to be a positive number in need that to be a positive number in need that to be a positive number in order to be able to do the calculations order to be able to do the calculations order to be able to do the calculations if that was a negative number do if that was a negative number do if that was a negative number do probably to having the motor on the probably to having the motor on the probably to having the motor on the other side of the lens I would need to other side of the lens I would need to other side of the lens I would need to click on reverse motor in order to make click on reverse motor in order to make click on reverse motor in order to make it a positive number I'm now going to go to the close focus I'm now going to go to the close focus part on the lens my close focus mark is two feet which is my close focus mark is two feet which is 61 centimeters so I can put 61 61 centimeters so I can put 61 61 centimeters so I can put 61 centimeters there and I can left click centimeters there and I can left click centimeters there and I can left click right click store there and I now have right click store there and I now have right click store there and I now have three motor positions and three target three motor positions and three target three motor positions and three target distances this is sufficient to define distances this is sufficient to define distances this is sufficient to define the curve of this lens so I'm now going the curve of this lens so I'm now going the curve of this lens so I'm now going to use calculate and precious once now to use calculate and precious once now to use calculate and precious once now that I've done the calculation the lens that I've done the calculation the lens that I've done the calculation the lens scaling has changed and the lens factor scaling has changed and the lens factor scaling has changed and the lens factor has been calculated for me I can now has been calculated for me I can now has been calculated for me I can now apply this data this uses it in the apply this data this uses it in the apply this data this uses it in the setup that I am doing and it says here setup that I am doing and it says here setup that I am doing and it says here lens factor has been changed and so has lens factor has been changed and so has lens factor has been changed and so has the focus actually scaling these changes the focus actually scaling these changes the focus actually scaling these changes have not been written to disk okay so I have not been written to disk okay so I have not been written to disk okay so I can exit from this box there is my lens can exit from this box there is my lens can exit from this box there is my lens factor because that has not been written factor because that has not been written factor because that has not been written to disk I'm going to write it to disk by to disk I'm going to write it to disk by to disk I'm going to write it to disk by clicking on save and I'm going to use it clicking on save and I'm going to use it clicking on save and I'm going to use it today by clicking on apply now I can today by clicking on apply now I can today by clicking on apply now I can look at my real focus axis and I can look at my real focus axis and I can look at my real focus axis and I can right click there and go into my focus right click there and go into my focus right click there and go into my focus axis scaling this is the real focus axis axis scaling this is the real focus axis axis scaling this is the real focus axis that I am setting up that drive for that that I am setting up that drive for that that I am setting up that drive for that motor on that lens I have a minimum motor on that lens I have a minimum motor on that lens I have a minimum limit set at 0 because when my length is limit set at 0 because when my length is limit set at 0 because when my length is on Infinity focus is closest to the film on Infinity focus is closest to the film on Infinity focus is closest to the film plane which is makes it a minimum limit plane which is makes it a minimum limit plane which is makes it a minimum limit so therefore my minimum limit is 0 I can so therefore my minimum limit is 0 I can so therefore my minimum limit is 0 I can now take my lens to my maximum limit now take my lens to my maximum limit now take my lens to my maximum limit which may be closer than the last mark which may be closer than the last mark which may be closer than the last mark on the length and on the length and on the length and look at the lens and see if that's the look at the lens and see if that's the look at the lens and see if that's the tape I found I actually have some extra tape I found I actually have some extra tape I found I actually have some extra travel on the lens that allows me to go travel on the lens that allows me to go travel on the lens that allows me to go closer than the two feet marked on it so closer than the two feet marked on it so closer than the two feet marked on it so I now have a maximum limit this will I now have a maximum limit this will I now have a maximum limit this will stop me driving the motor past the end stop me driving the motor past the end stop me driving the motor past the end stops of the lens I left click right stops of the lens I left click right stops of the lens I left click right click store I now have a point there click store I now have a point there click store I now have a point there that is my maximum limit I have a that is my maximum limit I have a that is my maximum limit I have a minimum limit a maximum limit I have an minimum limit a maximum limit I have an minimum limit a maximum limit I have an internal scale and I have an axis internal scale and I have an axis internal scale and I have an axis velocity and an axis acceleration velocity and an axis acceleration velocity and an axis acceleration these values are arbitrarily chosen in these values are arbitrarily chosen in these values are arbitrarily chosen in order to allow me to move my lens if I order to allow me to move my lens if I order to allow me to move my lens if I had a very stiff or sticky lens I might had a very stiff or sticky lens I might had a very stiff or sticky lens I might need to reduce these but this value need to reduce these but this value need to reduce these but this value showed that I believe I can go from one showed that I believe I can go from one showed that I believe I can go from one end of the lens to the other with this end of the lens to the other with this end of the lens to the other with this motor in point six of a second which is motor in point six of a second which is motor in point six of a second which is a reasonable figure for a bolt so with a reasonable figure for a bolt so with a reasonable figure for a bolt so with these changes having been done I'm going these changes having been done I'm going these changes having been done I'm going to save apply that lens that lens setup to save apply that lens that lens setup to save apply that lens that lens setup motor position wise is now done in order motor position wise is now done in order motor position wise is now done in order to be able to come back and use that to be able to come back and use that to be able to come back and use that motor position setup again I need to motor position setup again I need to motor position setup again I need to store that real information as a library store that real information as a library store that real information as a library file within this lens so I'm just going file within this lens so I'm just going file within this lens so I'm just going to put my cursor on this button and to put my cursor on this button and to put my cursor on this button and right click only which tells me that my right click only which tells me that my right click only which tells me that my current focus axis configuration has current focus axis configuration has current focus axis configuration has been read into my lens setup ok now been read into my lens setup ok now been read into my lens setup ok now within here I have a correct focus axis within here I have a correct focus axis within here I have a correct focus axis so I can now check customized focus now so I can now check customized focus now so I can now check customized focus now when I save apply this lens that focus when I save apply this lens that focus when I save apply this lens that focus axis will be written over that focus axis will be written over that focus axis will be written over that focus axis let's check to see that our scaling axis let's check to see that our scaling axis let's check to see that our scaling has worked I'm in a position with my has worked I'm in a position with my has worked I'm in a position with my vault I'm going to left click right vault I'm going to left click right vault I'm going to left click right click and store the position of that click and store the position of that click and store the position of that axis and I'm gonna use my focus axis in axis and I'm gonna use my focus axis in axis and I'm gonna use my focus axis in a focus follows target mode and enable a focus follows target mode and enable a focus follows target mode and enable the focus axis so the focus axis motor the focus axis so the focus axis motor the focus axis so the focus axis motor is now powered and I can put in target is now powered and I can put in target is now powered and I can put in target distances if I put a hundred and fifty distances if I put a hundred and fifty distances if I put a hundred and fifty three there and go to position one three there and go to position one three there and go to position one through the go to my lens is pulling through the go to my lens is pulling through the go to my lens is pulling focus to a position 153 centimeters focus to a position 153 centimeters focus to a position 153 centimeters which corresponds to five feet so that which corresponds to five feet so that which corresponds to five feet so that is correct I can now put other distances is correct I can now put other distances is correct I can now put other distances in here I can put 92 in there and go to in here I can put 92 in there and go to in here I can put 92 in there and go to position one and find it's slightly position one and find it's slightly position one and find it's slightly under three feet which is correct if under three feet which is correct if under three feet which is correct if there are significant errors in there are significant errors in there are significant errors in positions between the two the three positions between the two the three positions between the two the three points as I put in then that either points as I put in then that either points as I put in then that either means we've done it incorrectly or it means we've done it incorrectly or it means we've done it incorrectly or it means that the lens isn't actually a 50 means that the lens isn't actually a 50 means that the lens isn't actually a 50 millimeter lens but these are 51 or 49 millimeter lens but these are 51 or 49 millimeter lens but these are 51 or 49 or something in between this is been a mark of a commercial this is been a mark of a commercial control training video thank you for control training video thank you for control training video thank you for watching watching watching [Music]