All fisheye zooms start with a black circle for fullframe ?

What are the fisheye zooms at the moment, I know the Canon 8-15, Tokina 10-17, but do they all start at the widest mm's with a black circle around the pic ?

Isn't there a lens that start with fisheye effect (without black circle) and when you zoom in it's a normal wide-angle?

I'm not sure what you are asking, but to clarify for a 35mm format (FF) camera:

1) An 8mm fisheye lens will be what is known as a circular fisheye, meaning it shows a 180 degree angle of view across the short axis of the sensor/film. Everything beyond 180 degrees will be black.

2) A 15mm fisheye lens will be what is known as a diagonal fisheye, meaning it shows a 180 degree angle of view across the diagonal of the sensor / film. Since no part of the sensor / film is beyond the 180 degree area, no part of the image will be black.

A zoom lens like the Canon 8-15L is a fisheye at all focal lengths, ranging from circular at the wide end to diagonal at the long end.

I don't know what you mean by a 'normal wide angle' but there are no fisheye zoom lenses that are fisheye at some part of the range and rectilinear at another. Such a design strikes me as likely impossible to make.

I'm not totally familiar with the 10-17 zoom, but I suspect based on its focal lengths that it is designed to be a diagonal fisheye on the three formats (1.6X, 1.3X and FF). It should not be wide enough to be a circular fisheye on any of the formats, although it seems like it would be close on FF.

As GeffreyG said, it is probably not possible to design a zoom fisheye that becomes non-fisheye at the long end of its range. My inspection of the lens sample image archive forum showed that the Canon 15mm/2.8 is indeed a full-frame fisheye, whereas the 8-15L is a circular fisheye - circular image on black background - on full-frame at 8mm and a diagonal fisheye at 15mm.

One possibility is to get either a circular or diagonal fisheye and use software to "defish" the results. This results, of course, in a loss of quality at the edges, which may or may not be acceptable.

I "defished" some shots I took on film some years ago with the Canon FD 15mm fisheye. The results were not great at the edges, but my scanning equipment did not produce very sharp results anyway. I have gotten better results with the Rokinon 8mm fisheye on my 60D and 70D. The results seem fairly decent at the corners.

CanonYouCan wrote in post #16984232
Isn't there a lens that start with fisheye effect (without black circle) and when you zoom in it's a normal wide-angle?

I suppose what you mean by "normal wide-angle" is a lens that renders all straight lines in the subject as straight lines in the image. These are called rectilinear lens.
The 16-35mm f2.8 is a good example of a ultra-wide angle rectilinear lens. At 16mm, it is a 100 deg FOV with a FF sensor. It is impossible to make a rectilinear lens with a 180 FOV.

The other type of ultra-wide angle is what is called a Fisheye lens. They do not attempt to make straight lines straight. They render straight lines as curved (away from center of lens) . Fisheye lens are called Rectangular Fisheye lens when they fill the frame (without any black areas and only 180 deg FOV along diagonal) and are called Circular Fisheye lens when they render a circular image and show a true 180 deg FOV-vertical, horizontal and diagonal.

I have not heard of any zoom lens that can change from fisheye to rectilinear as it zooms.