Telephoto reflex lens for video

[RyanMKincaid]

Anyone ever use a telephoto reflex lens on a 7D for video?

I'm thinking about getting a cheap 500-600mm reflex lens. The one I'm looking at has a max apature of f/8.

I'm looking to get is a nice shot of the moon at night. I checked youtube but couldn't find any video samples.

The only information I could find mentioned the lens being too slow for photography and Brokah (spelling?) but nothing about video.

Any help would be welcomed, thanks.

 

[Samuel H]

you mean a mirror lens, right?

I've read these cheap ones are horrible, just a waste of money, but any decent alternative will be much more expensive

currently, my longest lens is a vintage 300mm; it cost me under 200eur, but it is 25cm long, 10cm wide, and weights well over 2kg; let's not even talk about handheld: my cheap-ish $100 tripod won't take usable footage unless there's absolutely no wind (even indoors, depending on the floor, it may shake visibly if there's people walking around the tripod)
I still haven't tried to use it to get some moon shots, but I really should

for longer focal distances, my approach is to wait untill I have a camera with sharp sensor crop (I guess just one or two years)



plus: not all mirror lenses are bad, check this big boy!!:
http://cgi.ebay.es/Carl-Zeiss-Penta..._Foto_Camcorder_Objektive&hash=item35b13f1813
here you can get a sense of how shockingly big this lens is; those are medium format cameras and lenses (my 300mm is in the back row, second on the right)
http://www.pentaconsix.com/1000mm.htm

 

[ROCKMORE]

I'm thinking about getting a cheap 500-600mm reflex lens. The one I'm looking at has a max apature of f/8.
I'm looking to get is a nice shot of the moon at night. I checked youtube but couldn't find any video samples.

Try one of these to experiment with until you have cash for a quality lens. This lens is pretty sharp and the reason it can be so cheap is because it has few elements and they make millions of the same lens with different brand names.
I bought the same lens with the Bower brand on it years ago. For the low price you will discover how much you will really use a lens this long before spending 2 grand. F8 is slow but in daylight you will probably be at 11 or 16. I have also heard the mirror lenses produce a crap image as Norman mentioned.

http://cgi.ebay.com/500mm-Lens-Canon...item53e70d9a60

I grabbed the 2 photos below from Goggle Images and can say from experience the moon shot was from that cheap lens. Not much to loose to try.

 

[Kin Lau]

A little late to this, but 500/8 mirror or reflex lenses are fine as long as you're aware of the limitations. The aperture is fixed, and any out of focus highlights are horribly distracting, and contrast is lower.

On the upside, many come with ND and other filters, they're cheap, have fairly good sharpness and because of the design, are generally free of chromatic aberrations. Some of the Russian 500/8 mirrors are also made of steel and come with a built-in tripod mount - you'll just have to get over the stinky leather smell.

BTW, to get a moon near full-frame, you need over 1000mm on a 7D.