dSLR image feed TTL to computer screen

A colleague wants to see what a digital still camera sees in real time on a computer screen. Basically we want to do this with a camera attached to a microscope so we can focus better than using the tiny screen on the camera and zooming in with the digital zoom to focus and back out again to take the image. Do any current off the shelf dSLR camera support this? (We can figure out how to hook up to a microscope.) We keep hearing that this is easy to do but so far no one has provided any specifics.

I am a Nikon user, and know most of the Nikons will do this (either wired up or with a wireless transmitter).

But you will need Nikon Capture to do this. The function is called "Remote Camera Control".

I'm sure other cameras will do this too.

Alex

Hi!

The problem with dSLR ist that SLR in general means to direct the image either to the finder or to the sensor. You usually can't have both because the mirror and shutter will ensure that the sensor can't produce a life image.

The only exception to this rule are cameras that use split prisms to branch out part of the light instead of a mirror or if the camera has an electronic shutter and allows a life image while closing the finder with the mirror.

I don't know of any dSLR that works this way. There's only the (no longer produced) Olympus E-20 (split prism) but as an all-in-one there may arise problems attaching it to a microscope.

The Olympus E-System cameras (E-1, E-300) may be remote controlled through the Olympus Studio software. There's also an SDK available to build camera control into your own software. You may either control the camera from the body itself or completely remote through the PC.

There's no chance (neither with Nikon, Canon nor Olympus) to get something close to a life image. You may shoot a series and evaluate it frame by frame.

I would use the optical finder (maybe with an angle finder and magnification) to focus. That's usually far better and faster than using an image on the PC. It might get tricky if the subject is pitch dark and you ned long exposure values to get a proper image. In this case focusing through the camera could be a better way. It wouldn't be "realtime" in that case though (due to the long shutter times).

Helge ;-)=)

Hi,

Nowadays you can have this piece of equipment and voila, life images on your screen.

Kees

Hi james, I do a lot of microscope work with my DSLR, if you have a trinocular microscope, my approach is to first calibrate the position of the camera on a very sharp subject, scalpel blade or small hypodermic needle, once the object is sharp in the eyepiece then move your camera up or down until its sharp on the computer screen then you have a winner, my experience is that most camera to microscope connector are not a drop and forget affair but once you find the mutal focus position of the camera and eyepieces this one doesn't change. forget about trying to have real time with DSLR even with eyepiece attachment, they are not sharp enough for the critical focusing needed for microscope photography

I go diving in Bermuda once in a while so if you need anything from the main land let me know. BTW what the main subject under the lens, organic or chemical, in my case I do mostly parabenzene crystals under polarized light.

I think the Canon 20Da will do what want. It's made for astronomers who wants to focus with the camera attached to a telescope. It also has the IR filter removed, but that easy to fix if it's important to you at all.

http://www.letsgodigital.org/en/news/artic...story_2550.html

I heard about this version of the 20D, have yet to have a comfirmation for a North american market. nice feature to have on board any camera

Come to think of it, you might easily adapt an Olympus C7070 or a similar camera and get real time imaging. in anycase it look easier to adapt than a DSLR, this compact has an incredible macro mode that sould be able to focus on the projected image of the eyepiece "sans problème", they have USB connectivity, raw mode, a video feed and most important, a housing for those after hours dive at Elbow Beach .

Thanks for all the helpful replies.

As for what I’m doing: I’m actually “borrowing†the dissecting scope of the Director of the Aquarium to photograph newly settled corals. We are collecting corals of known species and bringing them to the lab so that when they spawn and the planula settle we know exactly what we have and how old they are. Anyway, the director asked me this question and I didn’t have an answer so I thought I’d post here and tap into the vast knowledge base available at wetpixel.

The microscope in general is used to photograph all kinds of things but most are marine life. We are working with a Coolpix 5700 now and use the digital zoom to focus. The microscope’s and camera’s focus are not at all coupled. We are able to get good shots with this but using the digital zoom and tiny screen on the camera is not ideal. Sometimes when you zoom back out the camera loses focus.

The 20da sounds like a great option, especially since I’m already learning the

Canon 20d system.

Elbow beach sounds like and even better option! :-) Please look me up next time you are in Bermuda. I'm at the Bermuda Biological Station for Research.

James

Will do that ! my resident Buddy's name, Eric Graham his a member of the local dive club and just added a new born to his lifestyle, so his civil liberty have been curtailed somehow, last time over there I did four dives (very,very shallow) at devil's hole and did 500+ shots of blenny's condos, great little spot and not used by the locals.

Here's a great source for optics and microscope mounts. They carry high resolution frame grabbers and offer live video as well. Great for microscope work.

http://www.edmundoptics.com/onlinecatalog/...yid=173&level=2

Curtis

Will do that ! my resident Buddy's name, Eric Graham his a member of the local dive club and just added a new born to his lifestyle, so his civil liberty have been curtailed somehow, last time over there I did four dives (very,very shallow) at devil's hole and did 500+ shots of blenny's condos, great little spot and not used by the locals.

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I'm pretty sure I met your dive buddy and family at the dive club meeting last Wed. where I gave a talk on cephalopods. Bermuda is a small place indeed! But lovely.

James

I heard about this version of the 20D, have yet to have a comfirmation for a North american market. nice feature to have on board any camera

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It's here. Came across this when I was following up on a rumor about a possible 20D replacement.

http://consumer.usa.canon.com/app/html/d_e...20Da_061705.htm

Thanks Herb, I will track down my Canon rep and electrocute him <_< , those thing I should know about in my field of work.

This is what you want:

http://www.microscopyu.com/articles/digita...0/hardware.html

I use these for imaging fish scales on a microscope, and it is set up to work with any microscope, and give very high res images with realtime viewing and focus capabilities. I think the images are about 10 megapixels, and the cost is about the same as a high end digital slr.