darren_searle Loc: Brisbane Australia

Hi, I'm on a limited budget (I know wrong hobby) and would like a good telephoto lense for yachting photography. I have seen 500mm mirror lenses on eBay and curious as to the pros cons and general thoughts on theses!
Thanks
Darren

snowbear

They are typically very slow, meaning they won't work well in lower light without long exposures.

darren_searle Loc: Brisbane Australia

The lens I'm looking at is an f6.3 plan most of my shoots being middle of the accros water, so would be expecting high light levels...

GoofyNewfie Loc: Kansas City

Cheap & compact way to get the length.
I used to have a Nikon 500 f8.
It was fairly sharp, but not as sharp as aa regular refractive lens.
Hope you like doughnuts:
http://www.darrencarroll.com/blog/2011/11/time-to-make-the-donuts-going-old-school-with-mirror-lenses/

Nikonian72 Loc: Chico CA

I own a Nikkor 500-mm Reflex f/8 (fixed) lens. I have use it for the occasional bird photography. I have no idea what kind of DOF is possible at "boating" distance. Exposure control is ISO selection and shutter duration.

Out-of-focus water highlights will register as circles.

http://farm8.staticflickr.com/7032/6490284243_a865101d34_b.jpg

http://farm5.staticflickr.com/4074/5447456006_4d48d07ce2_b.jpg

bull drink water Loc: pontiac mi.

i have a cheaper one and got some good images.i've never had any doughnut holes. looking at the post above,i'd say if you get a good one you'll do fine.crank up the iso and go for it.search the web for a dof scale for a 500mm lens. saw one awhile ago but i can't remember where.

dpullum Loc: Tampa Florida

Darren: The subject was also covered in a previous UHH post; use search at the UHH header.

Mr. N-72... the subtle variations in the white feathers is fantastic. Your control of the exposure is superber.

bobmcculloch Loc: NYC, NY

if you have an android smart phone there are free DOF apps available, Bob.

ngc1514 Loc: Atlanta, Ga., Lancaster, Oh. and Stuart, Fl.

The other big consideration with mirror lenses is contrast. A well designed catadioptric (mirror-lens) system will have good internal baffling. I've seen cheap Russian made ones that didn't. Look through the camera mount part of the mirror-lens and you should not see ANYTHING but the aluminized spot on the backside of the corrector plate at the front of the lens. Point it near (BUT NOT AT!!!) the sun and see if there are any reflections or hot spots showing up inside the lens.

The old Nikkor catadioptric lenses had excellent light baffling and good contrast. Some of the newer imports, not so good. Any extraneous light getting through the baffle tube will decrease contrast.

As for the donuts from specular reflections. Look above the heron's talon at the left and then up to the point where the white foam meets the blue water. You'll see several donuts in the image. This is the shadow of the reflective spot on the backside of the corrector plate and nothing can be done about it. It's inherent to the optical system.

wilsondl2 Loc: Lincoln, Nebraska

One other way to go is a Spiratone 400 from eBay. Should be able to get one for around $25 and the T mount will be under Before you bid ask the seller if the real elemint is foggy lots of them are. I have both and the 400 is sharper and you can stop it down. - Dave

2th Loc: Tehran

Yes ,yachting photography that is whole day photography. till dust. no problem with 500 or 600 mm mirror lenses.