Phoenix 500mm f/8 lens

[mwt]

I bought a canon rebel XT with a 28/300mm Lens to take pictures of my kid playing softball.

The season has started and I do not like the angles I have to shoot at . I either have to get in the dugout or shoot thru the fence.

I found this Phoenix 500MM lens f/8 with a 2x converter and I thought I could go to the outfield and get better angles.

Has anyone ever used this brand of cheap lens?

Also can I do the converter on my sigma lens?

Do they work ?

Thanks for the help

Mike

[another view]

A 2x converter should work with most any lens but there are a couple of drawbacks. First, you'll lose two stops so with that F8 mirror lens, you'll only have F16. You'll probably have to boost your ISO to 400 or 800 to get a decent shutter speed and really need to use a tripod or at least monopod with a lens that long. TC's can also lose some sharpness, but usually that's more of a problem with a zoom. I don't know if you're familiar with mirror lenses, but they will show out of focus highlights as rings (kind of like "doughnuts"). It can be a cool effect but, like a fisheye lens, the effect can be overused.

Auto focus cameras need a maximum lens aperture of f5.6 or larger for autofocusing. They might work with a lens a stop slower than this, but it will be very slow and might not be accurate.

[dmm96452]

I have that lens. (if it's the one I think it is)

Understand that it is full time manual focus and the apeture is controlled manually as well. I picked it up to get shots of the moon. It is not a mirror lens and as a result is very long. You'll need a tripod or monopod to hold it steady.

With all of that said, it takes a decent picture if you stop it down a little. Not bad for limited uses for $100.

[another view]

I just assumed it was a mirror lens - most 500 f8 lenses are, and I think they make one even. You know what "assume" means...

Sigma has a 500 f7.2 (not a mirror lens either) that I had for awhile. It is advertised as autofocus, but once again that f5.6 rule held true here too. Not horrible, but nothing like the big, bright, sharp f4 lenses from Canon or Nikon. Of course without the price too!