I've been reading some of the previous suggestions, including re-reading my own, and I think we have gotten somewhat off-base.
First, you state you are brand new to photography and want to do astrophotography, landscapes, portraits and close-up photography. You also plan to hike with your gear.
Taking all that into consideration, I'd recommend the following:
CAMERA:
First and foremost, I don't think you should get the 5D Mark III. It's way more camera than you need for your stated, primary purposes and, in fact, as a beginner you might find it's pro-oriented complexity a bit overwhelming and frustrating... especially the highly customizable 61-point auto focus system that might be important for sports/action/wildlife shooting, but isn't really needed for the type of stuff you say you want to shoot. An easier to use full frame and similar resolution EOS 6D would meet your needs very well, with a more straight-forward 11-point AF system it's smaller, lighter, at least $1000 less expensive, plus it has built-in WiFi (a separate, $700 WFT-E7A is needed for wireless connectivity with 5DIII). Many people also consider the 6D the best low light camera that Canon currently offers (lowest image noise at higher ISOs and during long exposures). Instead of spending $2400 on a new 5DIII, you can get a new 6D for $1400... or save even more by buying a refurbished 6D from Canon's online store for $1100. Refurbs from Canon are typically near new, fully checked out and have the same warranty as new.
LENSES:
Spend more on these... not less. Lenses are arguably more important than the camera they are used upon. The camera simply needs to capture what the lens "sees". The lens decides the overall quality, feel and look of your images. I think many people overspend on their camera.... and then short themselves on the lenses they buy to use on it. I'd much rather have a set of high quality lenses and an entry-level camera model, than a high-end camera with only one or two less capable lenses.
14mm f2.8 Samyang/Rokinon is a brilliant idea for astrophotography and super wide landscapes. It's only about $300 new. In addition to the Samyang and Rokinon names, it also is often rebranded and can be found selling under Bower, Dot Line, ProOptic, Vivitar and possibly some other brand names. (Vivitar calls it a 13mm, by the way.) But it's the same lens, regardless... so shop around to get the best price you can. Now, the Canon 14/2.8L II is a much better built and optically superior lens with auto focus and electronic aperture control. But it's also far more expensive. I have been considering the 14mm Samyang/Rokinon/Bower/etc. myself, as it's one of the widest avalable for full frame cameras and is a real bargain that I think would meet my occasional needs for a lens of this type pretty well. Just be aware that it's strictly manual... both focus and aperture control. Manual focus is already more difficult when using modern AF-oriented cameras... and a manual aperture also will cause your viewfinder to dim down as you stop the lens down, making manual focus even more challenging. (Hint: Use Live View with Exposure Simulatioin turned on to compensate. It's also possible to zoom in Live View to check focus.) Also be aware that this lens has a strongly convex front element that makes it impossible to mount standard filters. And, this lens is known to have some "moustache" distortion... that can be a problem if shooting architecture or other subjects with perfectly straight lines, where the distortion might be obvious. But for most astrophotography or landscapes, it likely won't be any issue at all. If it is, there are softwares and lens profiles that can largely correct the distortion. One other thing... buy the lens from a reputable store that has a good exchange policy and test the lens immediately when you receive it. Apparently there is some small percentage of these lenses that have de-centered elements - either snuck by quality control or were mishandled in shipping - and that causes images with uneven sharpness. So test it right away and look carefully that there is no problem with one side or the other of the images being "soft". If it is, contact the retailer promptly to exchange it for a good copy.
I still like the idea or the EF 24-70mm f4L IS USM as a high quality, general purpose, "walk-around" lens. Yes, the EF 24-70/2.8L Mk II is an even more premium lens... It gets rave reviews, but is bigger and heavier, plus considerably more expensive. Twice the price, in fact. $1800 vs $900.
If you feel the need for a faster (larger aperture) lens, get a prime to complement the walk-around zoom. You might pick from Canon EF 20/2.8 USM ($500 w/separate hood), EF 24/2.8 IS USM ($650 w/separate hood), EF 28/1.8 USM (fairly compact, $525 w/sep. lens hood), EF 35/2 IS USM ($650 w/sep. hood), EF 50/1.4 USM ($375 w/sep. hood), EF 85/1.8 USM ($425 w/sep. hood), EF 100/2 ($525 w/sep. hood) and/or EF 135/2L USM ($1000).
As an alternative to the last three, short telephoto lenses (for portraits), you might instead get a macro lens that can serve dual purpose. Check out Canon 100/2.8L IS USM ($850) or Canon 100/2.8 USM ($575 w/separately sold lens hood). Both these Canon macro lenses can optionally be fitted with a tripod mounting ring that costs $150 to $170, IIRC. Alternatively, there are the Tamron 90mm (original version, $500) and 90mm VC USD ($750)... or the Tokina 100/2.8 ($350)... or the Sigma 105/2.8 OS HSM ($770).
If you would prefer a telephoto zoom, I'd recommend the EF 70-200mm f4L IS USM. It's considerably nicer to hike with than the larger, heavier f2.8L IS USM II version. The f4 also is less expensive at $1140 (plus $160 for a tripod ring), versus $2000 for the f2.8 (tripod ring included). For close-up photos, lacking a macro lens this zoom can also be used with macro extension tubes (Canon 12mm tube $82, Canon 25mm tube $136, or Kenko tube set w/12, 20 & 36mm $104).
At least initially, try not to duplicate the focal lengths of any lenses you might get. For example, don't get two that offer 24mm. Instead, with a 24-70, get a 14mm and/or 20mm, perhaps along with a 90mm or 100mm macro (unless you get a 70-200mm). This way you have a more versatile lens kit. Later you might find a specialized need that calls for some duplicated focal length.
Yes, there are "faster" versions of some of the above primes... f1.4 and even f1.2 in some cases. They are bigger, heavier and more expensive. They also might not be as sharp edge-to-edge, as their "slower" counterparts.
All the above Canon lenses also might be found refurbished for some savings. Refurbs are small quantity, may be out of stock, and tend to sell out quickly. So it may take some patience waiting for what you want to come available, and you gotta move quikcly when they do.
TRIPOD:
Regarding tripods, I'd recommend at least planning to spend more... and shopping used. Bought right, a really good tripod will last a lifetime. And bought used, you can save a tone of money.
I have a 30+ year old Bogen (which eventually merged with and became Manfrotto). It's a heavy duty aluminum model that I really don't want to carry around any more.... probably 15 lbs, but seems like 25. It's now pretty much only a studio tripod, It seems like it will last forever! But, truly solid aluminum tripods are heavy. Mine is I really don't want to carry around any more.... probably 15 or 16 lbs, but seems like 25 or 30! It's now pretty much only a studio tripod, I really don't want to carry it around any more.
About 15 years ago I bought a brand new Gitzo 1325 carbon fiber.... just as strong as the old Bogen, actually thanks to the carbon fiber it's better absorbing fine vibrations than metal, and it's considerably lighter, as well as faster to set up. It was an expensive purchase, but I am using some heavy and pricey lenses on it and really don't want to trust them to a "lesser" tripod.
Anyway, a year or tow ago I bought another Gitzo G1325 Series 3 Systematic tripod as a backup, with an accessory G1321 leveling platorm... used but really looking like new... for $325 including shipping. (For comparison, the current equivalent Gitzo tripod sells for over $900 and the leveling platform costs another $295.) Since it's a backup, I also economized on the ballhead to use on it, buying a $60 Smith-Victor heavy duty (50 lb. rated) BH8. Frankly, I was suprised how well the cheap, Chinese-made S-V ballhead compared to a $450 Kirk BH-1 I have on my primary tripod. I also installed LegCoats on the tripod ($45, padding that both protects the tripod and makes it more comforatble to carry) and got a nice Hakuba tripod bag to store and carry it in ($50).
Actually, with lighter gear such as the 6D and lenses mentioned above, you probably wouldnn't need as heavy duty tripod or head as me, probably saving both cost and some weight on those hikes. They are harder to find because they only started making them more recently, but Gitzo Series 2 are a bit smaller and lighter. AFAIK, the older models like the G1541 are only available in the Reporter or Mountaineer series, which have a permanently installed center column. They now make some Systematics, which are modular and can be used without any center column (makes for a more stable t'pod). Also you'll find both series that have 3-section and 4-section legs. Fewer leg sections make for a more stable tripod... but more sections allow the t'pod to be taller and/or fold up smaller. More sections also can be a little slower to set up. Gitzo also offers Traveller series tripods with 5- and 6-section legs, which might be very compact, but I'd worry about stability for long, nighttime exposures.
Likewise, a little smaller and lighter ballhead like the $60 Smith-Victor BH5 or even smaller/lighter $53 BH2 might suffice, for your gear and purposes.
Unless you get into wildlife/bird and sports photography using big telephotos, then you might want the heavier duty tripod and head.
There are other types and brands of heads you might consider. I've focused on ballheads because they are popular for their compactness, when hiking or travelling. The other major type are pan/tilt heads, with longer, protruding control handles that might give a bit more precise control. There are also some specialized types, such as fluid pan/tilt heads, gimbals and grip type ballheads.
All the heads I've mentioned have Arca-Swiss style quick release platforms. That's the type of QR I'd recommend, because it's the most versatile and ubiquitous. Many manufacturers make items that are compatible with the A-S system. But you will need corresponding QR plates on your camera and on any lenses with tripod mounting rings. For the camera, I recommend spending the extra for a custom plate specifically for it. Those cost around $50, but are fitted to provide anti-twist feature. Kirk, Wimberley, RRS and others offer them. Lens plates are more generic and made by many different manufacturers, simply come in a variety of lengths.
FLASH:
It's hard to go wrong with Canon's own flashes. They are excellent and easy to use. Mainly you just need to decide how much power/output you want... versus size, weight and cost. The 600EX-RT is the most powerful, largerst, heaviest and most expensive. Somewhat smaller is the 430EX, a second version of which is now being offerd with radio triggering ("RT", which is especially useful in multi-flash setups). There's also the 320EX, which both serves as a flash and has a continuous lamp feature for videography. Even more compact are the 270EX II and 90EX.
Whatever you decide with flash, I'd recommend getting a generic flash bracket and off-camera shoe cord, to be able to position the flash higher and off to one side. This helps avoid redeye and also makes for nicer shadow effects. You also might want a diffuser of some sort on the flash head, for softer light output (better than "bouncing" the flash, whichwastes a lot of power and introduces other variables).
Have fun shopping!
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Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7D(x2), 50D(x3), some other cameras, various lenses & accessories
FLICKR & EXPOSUREMANAGER
