Sensor size in digiscoping (1 Viewer)

Are the needed shutter speed same with big sensor and small sensor cameras.

An example
Swarovski ATX scope + TLS APO adapter + T2/Nikon adapter + Nikon D3200

Put ISO 100 and take picture inside a big hall.

Then change sytem
Swarovski ATX scope + TLS APO adapter + T2/Nikon 1 adapter + Nikon V1 camera

Moving scope far so that the area in picture are same, and taking photo with same ISO and shutter speed.

Then checking the pictures, are picture with large sensor darker than with small sensor.

Yes, larger sensors need more light than smaller sensors so require slower shutter speeds all other exposure settings equal. Difference can be as much as 2-4 stops. However, larger sensors also have better High ISO performance, as much as 2-4 stops too.

If you do not print or crop your pictures a small sesnor camera can be a better choice for its higher shutter speeds and the longer effective focal length when digiscoping. But when using TLS APO type adapter, a large sensor is probably better choice to minimize diffraction.

Mirror slap ( and noise ) is a big problem with low shutter speeds and high magnifications.
Shooting the NEX 7 on the STX 95 and TLS APO gave me only 1 or two (in some bursts none) sharp frames in poor light.
The Nikon V1 in Electronic Shutter Mode had much better success rate (and longer bursts).
For any camera a remote would be preferable.
Neil.

Thanks

Panasonic GH 3 with electronic shutter shall be my choice.

Yes, some people get fine digiscoping results with removable lens cameras, but I do not. The major problem I have, even with the 4/3rds cameras, is shutter shock when the curtain rumbles across the sensor and jars the scope and camera. An electronic shutter may not solve the problem in that it only allows limited video resolution in some cameras. In others it may be a rolling scroll that is open much longer than the same exposure time with a mechanical camera and allows distortion.

A small sensor, such as in my Lumix FH-1 ( fs-10) is allows a shutter speed four times as fast as a 4/3 camrera, and 16 times as fast as a full frame sensor. I do not agree that the larger cameras can fully compensate by increasing the ISO with impunity. At most they may reclaim half of the lost speed without suffering quality loss compared with the point and shoot cameras. Go ahead, visit the IR comparometer and demonstrate the effects to yourself.

Small cameras digiscope near their sharpest optical design aperture, a stop or two below full open. With interchangable lenses people may use an f/2 lens at the scope determined f/stop of f/11 or f/16. Not a condition expected to produce the sharpest image.

A point and shoot camera using contrast autofocus detection will focus much better than a typical SLR. My favorite Lumix FH-1 (FS-10) is quite sharp and only weighs 120 grams and mounts nicely on the outer screw threads of a Baader Hyperion 17mm eyepiece, which is known to digiscope well. I attach threads to the body of the camera and connect with extension tubes. See my attached image of a sparrow shot at 40 feet. Click on the image for a larger view.
http://farm9.staticflickr.com/8304/7778422664_71b4cede51_b.jpg

I enjoy digiscoping with the little 120 gram Lumix. Cannot imagine using a camera that weighs another pound. The extra weight can distort the eyepiece and/or lens mounting, which is very critical to the collimation of the scope. Of course for a legitimate mounting a balance bar could be added that would weigh another pound. Gene