Without anything official to go on, I think the double lens hood setup is to accommadate the zoom range of the lens. You didn't mention what camera you're using but, I'd put money on using just the petal hood at the short end of the zoom, the normal hood at the mid-range, & both at the long end. The best way to check would be to put both on & see if you get any vingneting at the short end. If your camera is APS format, you may be able to get away with both over the whole zoom range.

This has to be 1 of my favorite shots. I took it while on my honeymoon in Germany. I was stationed at Zweibrucken AB at the time. We decided to take a trip up the Rhine River & come back down the Mosel stopping to tour castles & do wine tastings. This was at Burg Thurant in Alken, Germany about 8am while we waited for the castle to open for tours. The camera was probably a Canon F1 with a 50mm f/1.4 mounted. I didn't record the exposure or film type but, it was most likely Ektachrome X.

Spider Web Burg Thurant, Alken, Germany

(Download)

I found a very nice app for the iPad called SetMyCameraPro. It costs about $10.00 and includes a depth of field calculator. In the initial setup, you select the camera you're using. In the DOF calculator, you select the FL, aperture, & focus distance. The "readout" shows near focus, focus point, far focus, and depth of field. For this type of shot, it would make DOF calculations much simpler.

This was shot during the Thunderbirds show at Seymour Johnson AFB, NC in 1987. I used a Canon AE-1Program & Vivitar 20-210 f/2.8 zoom. I suspect the film was Ektachrome X or 100. The base Public Affairs office asked me to shoot slides as their folks (and the T-birds photog) were only shooting B&W. I submitted this one to the T-birds after the PA folks said they weren't interested in any of them. The T-birds liked the shot but said the image size was too small. The F-16's aren't identifiable as belonging to them. It's not the sharpest but, has always been 1 of my favorite shots.

You Canon & Nikon snobs get me. I'll put my Sony A850 & Tamron lenses up against anything you want to use in low light. It's more about the nut behind the shutter release than anything else.

Welcome to UHH, Neal. I started with a Minolta SRT-101 in the late 60's. I have to agree with most of the comments to practice & read the manual a chapter at a time. With digital you don't have to worry about wasting film & waiting to get your pictures back. Find a local camera club & ask for constructive criticism.

Just recently purchased a Samyang 500mm f/6.3 from B&H intending to use it for wildlife shots on the lake behind our house. It was only $150.00 plus another $10.00 for the T mount. The lens is great for still subjects or animals that aren't moving. I've attempted to shoot Redhead ducks & Canada geese swimming but they move too fast to keep sharp focus. If your subject is close & not moving, it's very good. Otherwise, wait for something that can autofocus. The attached photo was shot through our patio door with a Sony A850 & the Samyang 500 mounted on a monopod.

A lot of the work I'm willing to share is still in physical (read slides) form and my slide scanner died recently. A few shots are attached.

Greetings, all. I happened across this website quite by accident this evening.
My background dates back to 1964 when my folks bought me a Yashica 35mm camera to take on a camping trip to the Rockies during the summer between my junior & senior high school years.
I spent 4 years in the Navy as a Photographer's Mate & 18 years in the Air Force as a Photo Processing Control Technician (read that as QC). Since I retired, I've moved from shooting slides to digital.
My current setup is a Sony a850 with a Tamron 28-75mm f/2.8 as the primary lens. I just recently purchased a 500mm f/6.3 mirror lens for shooting wildlife.