How do I increase the field of view in Measurement and Automation Explorer (MAX) Version 3.1.1.3003

[oceaneyes]

I am using Measurement and Automation Explorer Version 3.1.1.3003 to view pictures on a pc that are being sent from a video camera looking through a microscope.  The image I see in the viewfinder of the microscope is MUCH smaller than the image that is displayed on the pc screen.  Looking through the viewfinder of the microscope, I can see ~20 mm across the object, but the display from the camera in NI-MAX shows ~4.5 mm across the object.  How can I change how much of an object is displayed on the screen in NI-MAX?

The camera is attached to the microscope with a camera adapter on the top of the microscope.  The lenses the camera "looks" through and the lenses used when one looks through the viewfinder are the same, so theoretically, there should be no difference in what is displayed on the pc and what is seen through the viewfinder.  We have ruled out the microscope and camera as the cause of the problem, which narrows it down to the NI-MAX software itself.

I saw in the forums that you can zoom out on an image; however, this does not change the distance across an image that is seen, just makes the picture of the same ~4.5 mm across the object smaller in size.

Any ideas or suggestions?

[AnalogKid2DigitalMan]

oceaneyes-

I have never used MAX to view a video feed BUT I would not rule out the camera/optics just yet.

Ideally you should use a scope with a trinocular port that is specifically for camera use. Different manufacturers of scopes have different length optical paths between the main objective and the eyepieces. The eyepieces have a specific focal lenght to focus the virtual image from the main objective and magnify it to present it to your eye. If the camera and its lens have a different mag or focal length, the field of view and mag of what the camera images will be different from what your eye sees.

What type of camera is it? If it is analog NTSC or PAL you are in luck- just plug the analog signal into a TV monitor to really see what the camera is imaging- this will confirm if MAX is indeed the culprit.

[VuD]

Hi oceaneyes,

Thank you for using our forums.   AnalogKid2DigitalMan makes some very good points.  If you still are having issues, please post an image so we can get a better grasp of your problem and what you are trying to do.  Thanks.

Regards,
Vu D
Applications Engineer

[oceaneyes]

I have attached a picture of the object's image being displayed on the pc monitor.  Where the field of view (FOV) in the microscope is almost 30 mm, the FOV displayed onscreen is about 7 mm.  After contacting companies various times I discovered there was a reducing lens that goes in the C-mount adaptor, but it is over $300. 

I thought maybe that the FOV could be changed in in NI Measurement and Automation Exploer (NI-MAX).  Any ideas? 

---

[oceaneyes]

Here is the same picture as above in jpg format.

[AnalogKid2DigitalMan]

I do not think MAX will be able to expand the FOV beyond what the camera itself sees.

Can you plug your camera into a TV monitor as a sanity check to see what the true FOV is?

[AnalogKid2DigitalMan]

From this other post, I see it is a 1394 camera, thus disregard my suggestion of trying to plug it into a TV monitor

http://forums.ni.com/ni/board/message?board.id=200&message.id=11842

[gpadua]

Hi Everyone,

I think I'm having a similar problem. I'm using a CCD camera to try to get some fibre images, but although the magnification used is 1x, I'm getting augmented images and my FOV is only 1.3 mm.

If any of you could give me a hand, I would very much appreciate it

Thank you

[VuD]

Hello gpadua,

Thank you for using our discussion forums.  You can first try changing the acquisition parameters in Measurement Automation Explorer and using the zoom control.  However, if the issue is beyond the scope of these options, then it might be due to the limitations of the actual camera and lens as discussed earlier.  I have also attached a link to some information regarding lens focal length and FOV.  Hopefully this can give you a good start.

AE KB 2EFEP6K3: Calculating Camera Sensor Resolution and Lens Focal Length

Regards,

Vu D
Applications Engineer

[oceaneyes]

This is probably a dumb question, but let's say that my camera is "seeing" what is being displayed through the viewfinder on the microscope - and the software is zooming in for me so much that the field of view displayed is decreased.  There is no way to change the zoom in the software that would also affect the field of view?

Thanks for your patience.

July