Microscope Camera Techniques

Alantb · #1 (**permalink**) 14-05-2009, 05:36 PM

My original question on the 'Entoloma' thread was this: I have a trinocular Brunel microscope and I mount a Nikon Coolpix 4500 on the centre 'eye'. In order to see what I am going to photograph I connect the video output from the camera to a small, cheap, television using the 'AV2' position. This works well but the appearance on the television is of poor quality, only useful for determining the focus of the camera; small detail is obscure.
I originally ascribed the quality problem to the camera output - but if I take the camera off the microscope and use it like a close-circuit tv the quality is no worse than the average telly and much better than when on the microscope.
So what I want to do is to take an output directly to a laptop (or other PC) and view it dynamically. Plugging in the PC via USB is fine but I can only display the still images which I have already taken.
I have thought of getting a video-to-PC cable and adapter if such things exist but I suspect that the quality is determined by the microscope output.
Brunel staff, and forum members have suggested that I get another camera but i suspect that the real problem is something in the present system that may be cheaper to fix.

Any answers?

charlieb · #2 (**permalink**) 14-05-2009, 05:49 PM

Quote:

Originally Posted by Alantb

So what I want to do is to take an output directly to a laptop (or other PC) and view it dynamically.

So use the PC to display the video output instead of the TV? Your PC would need a video capture card/device to interpret the signal (I'm guessing the video output of the camera is a standard headphone jack style - did it come with a cable that splits into a couple of larger plugs, usually red and white, audio and video?)

I've never used it, but someting like a EasyCAP USB 2.0 Audio & Video Capture Adapter sounds like what your after (plugs into a USB port), or any of the internal (for a PC) TV card's should be able to feed from an external video source.

I would recommend taking your camera (and laptop) into a computer shop and trying out a few dongles.

Chris Yeates · #3 (**permalink**) 14-05-2009, 06:41 PM

Quote:

Originally Posted by Alantb

. . . . I have a trinocular Brunel microscope and I mount a Nikon Coolpix 4500 on the centre 'eye'. In order to see what I am going to photograph I connect the video output from the camera to a small, cheap, television using the 'AV2' position. . . . .

hi Alan

I use exactly the same system as you and have never felt the need to involve a telly

what are the advantages?

Chris

Alantb · #4 (**permalink**) 15-05-2009, 09:42 AM

Hi Chris;
I seem to have a problem convincing people that there is a problem ..... but when I plug the camera into the PC I can see the still pictures but I can't look at the output dynamically. In order to do that I have been using a small tv using the video output from the camera. It may be that I am short of a bit of software (and so is the pc..).
What exactly do you do? - I have roughly the same micro as yourself, is your camera the same one?

Yours, puzzled of Horbury

Alantb · #5 (**permalink**) 15-05-2009, 12:28 PM

Hi Charlie,
thanks for your input. That gadget isn't very expensive (~£19 inc software) so I might get one but I am wondering if I will still have a problem with the actual video output quality.

Cheers, Alan

Lancashire Lad · #6 (**permalink**) 15-05-2009, 12:55 PM

If I am right, what is needed is a means to connect the digital camera to the computer such that a "live feed" of what the camera is continuously seeing (both before and after the shot is taken) is shown on the computer screen. (i.e. using the computer screen in lieu of the LCD on the back of the camera).

Unless I'm missing something, this should provide clearer image to work with while the compositon of the subject is sorted out, as the computer screen will undoubtedly have a much better resolution than the camera's LCD screen.

Again, unless I'm missing something, the camera's sensor sends full quality pixel info to the on-board LCD, it's just that the LCD doesn't have enough pixels to render full resolution.

On this basis, assuming that the camera is capable of focussing properly down the microscope, such a set up should provide superior images, both on the computer screen, and in any actual photo's taken, than the typical dedicated 1.3 Mp microscope camera? - My reasoning being that you may have 5Mp or 10Mp to play with rather than 1.3Mp.

Regards
Mike.

charlieb · #7 (**permalink**) 15-05-2009, 03:48 PM

Quote:

Originally Posted by Lancashire Lad

My reasoning being that you may have 5Mp or 10Mp to play with rather than 1.3Mp.

Most cameras video outputs are s-video which, as far as I can find out, is limited to a resolution of less than 1024x768 - which is less than a 1MP - but ideal for TV's (which are something like 720×480).

So you may see an improvement on a higher resolution computer monitor (likely the one you already have).

SheffieldLass · #8 (**permalink**) 15-05-2009, 11:33 PM

Quote:

Originally Posted by Lancashire Lad

Unless I'm missing something, this should provide clearer image to work with while the compositon of the subject is sorted out, as the computer screen will undoubtedly have a much better resolution than the camera's LCD screen.

Again, unless I'm missing something, the camera's sensor sends full quality pixel info to the on-board LCD, it's just that the LCD doesn't have enough pixels to render full resolution.

On this basis, assuming that the camera is capable of focussing properly down the microscope, such a set up should provide superior images, both on the computer screen, and in any actual photo's taken, than the typical dedicated 1.3 Mp microscope camera? - My reasoning being that you may have 5Mp or 10Mp to play with rather than 1.3Mp.

Regards
Mike.

I think the same would happen as happens with higher resolution microscope cameras ... you are limited by the speed the graphics card on the computer can process the information, because you get a greater time lag with the 'real' time on screen, so that you overshoot on focussing etc which can be problematic. This is known to be a problem with microscope cameras with more than circa 2.1mp. This would be the case if you are relying on the screen as you adjust the focus or object positioning, rather than looking down the microscope, hence more is not necessarily better. Still photos would be better, up to a certain point, that is. Then the magnification of the microscope I guess becomes the limiting factor, in that you are then merely enlarging the 'fuzziness', as you get if you use higher powered eyepieces.

Alantb · #9 (**permalink**) 16-05-2009, 12:30 AM

Quote "If I am right, what is needed is a means to connect the digital camera to the computer such that a "live feed" of what the camera is continuously seeing (both before and after the shot is taken) is shown on the computer screen. (i.e. using the computer screen in lieu of the LCD on the back of the camera)."

Yes Mike, that's what I am on about; when I plug the camera into the PC via the USB cable all I can do is look at the stills which are on the camera card. There seems no way that the PC will take the place of the camera screen at the time I am taking the picture. This may be a function of the camera and not 'fixable' without intervention in the camera electronics.

Hence the problem.

Alan

charlieb · #10 (**permalink**) 16-05-2009, 12:02 PM

Quote:

Originally Posted by Alantb

This may be a function of the camera and not 'fixable' without intervention in the camera electronics.

You need to convert the PC into a TV, via the use of a capture card/device, such as the EasyCAP USB 2.0 Audio & Video Capture Adapter and the same cable you use to connect the camera to the TV.