will a t mount adapter fit my eos rebel t100? Is a canon eos rebel t100 a ef mount camera?

[kircohoe]

hello I need help finding an adapter for some lens that I had bought and I cant seem to find an adapter that will fit my camera which is a canon eos rebel t100. I have about 5 lens and I don't know the brand but I would love to use them for my camera. 

[Waddizzle]

Yes, the T100 is an EF mount camera.  A T-mount lens means a manual focus lens.  The T100 doesn’t feature any manual focusing aids.

Many T-mount lenses have fixed apertures.  They tend to be small, which may require higher ISO values compared to using an auto focusing EF mount lens. This means noisier photos. 

[ebiggs1]

" I have about 5 lens and I don't know the brand ..."

You will have to know the "brand" and the mount of each of the "about 5 lenses" you have. They may or may not be able to be adapted to your T100 by a T-mount or any other mount adapter.

" They tend to be small, ... This means noisier photos. "

This statement isn't, either totally clear, or its incorrect. A T-mount makes all kinds of lens equipment possible to mount on a DSLR like your T100. It could be, a telescope or a microscope, or a bellows, etc., and not limited to simple camera lenses per say. To connect a T-mount lens to a camera, you’ll need a T-ring specific to your camera brand and model. 

"A T-mount lens means a manual focus lens. "

All T-mounts are entirely manual, not only focus but exposures will be manual, too. AE metering, and image stabilization will not function. Since the T-mount is totally mechanical your lens in question needs to have a manual aperture collar. Otherwise the aperture will likely be stopped down to its smallest f-stop with no way to change it.

[kircohoe]

Thank you for replying. But I do need help finding a lens adapter. I have the brand names of the  camera lens that I have that I want to connect to my Canon EOS Rebel t100 camera. So the first lens I have is a vivitar series 1 70-210mm f3.5 Marco and then the other one is a Beston Marco lens. I believe all of them are t mount. 

[ebiggs1]

"I believe all of them are t mount."

Then all you need is the T-ring for a T100 it will allow you to mount T-mount lenses, telescopes, microscopes, and other optics to your Canon EF-mount camera body.