I have a MacBook Pro with 15" Retina screen. The screen is smaller than I would like for processing photos in Lightroom and I would like to buy an add-on monitor rather than buying a desktop set-up as the MacBook is good for everything else. It has USB-3 ports and a HDMI port. Operating system is OS 10.13.6. I would like a 27" screen and would love to stay under $400 if possible. Any suggestions would be appreciated.

"Some winners have been women." Are you kidding me?

For the crop censor, in Nikon parlance the FX, such as my D7100, the AF-S Nikkor 10-20 mm (15~30 in 35 mm film equivalen, or fulll frame equivalent) is a nice balance of reasonable price, sharpness and overall quality.

Never too late to start!

LOL!

I have the 70-300 VR FX and am very happy with it. It is a great compromise of value, quality and weight. You can spend thousands more for the same range of focal lengths if you are rich. If you are like me and think in terms of 35 mm focal lengths from the film days, that is the equivalent of 450 mm max, which gives you enough reach for most situations. Plus, with the VR you can hand hold in good light.

Видимо, я был неправ.

Well, at least the Russians haven't found this site (yet).

I've been following these discussions for a while now and have a humble suggestion for everyone who posts a question, whether it is about bodies, lenses, printers, whatever. Whenever you ask a question briefly indicate WHY you are shooting. For example: rank beginner, just want to take great pix to amaze my friends and relatives, just breaking in to stock photo sales, experienced pro. Also "I'm on a budget" or "I will bring my purchase home in my Bentley." This would help everybody who so kindly responds focus (no pun intended) or your question.

I have a D7100 and had a D70 before that (not to mention my first Nikon F in 1970). I am a big fan of the DX format for a number of reasons: (1) significantly cheaper; (2) lighter weight if that matters to you; (3a) the lenses are cheaper, sometimes significantly so, (3b) the lenses are lighter weight, (3b) you get the added bonus of lenses that act as if they are longer by 1.5 versus the full frame lenses, for example, I have an AF-S Nikkor 55-300 mm 1:4.5~5.6 GED (82.5~450 in 35 mm film/full frame D equivalent), so basically I am getting the equivalent of 450 mm of telephoto with high quality and a reasonable price [some will object to the variable aperture]; (4) technology is changing so fast that why buy a 10-year-old design? (the D7200 probably has some bells and whistles that my D7100 lacks); (5) quality: when I got the 7100 I took a favorite shot from Vienna, Austria and had a professional lab blow it up to 2 x 3 feet and it looked gorgeous; (6) it might just be me but I don't buy used stuff; what kind of warranty comes with it? So I would go with a new DX such as the D7200. [P.S. if you are wealthy or planning to make a six figure income from phtography, ignore all the above and get a new full frame.]

If you are on Facebook join the group Gringo Expats in Costa Rica. You will get an unvarnished look at what to expect, including some roads that are horrible to iinpassible and outrageous rental vehicle costs. Keep in mind also that, although CR is a small country it has a huge variety of geographic zones, mountain highlands, north Pacific coast, south Pacific coast, Carribean coast, etc. Also be aware that CR has very distinct wet and dry seasons varying by region. Foliage that might be beautiful in the rainy season might be dull and brown in the dry season. Do a lot of research because there are many pitfalls but many rewards if you do your homework. There are some excellent tour guides and guided tours (and a few bad ones) Lots of birds, monkeys, iguanas and crocodiles to shoot so bring the longest lens you can afford.

Consider the AF-S Nikkor 55-300 mm 1:4.5~5.6 GED (82.5~450 in 35 mm film equivalent) This is reasonably priced and will give you extra reach as compared to the tele-zoom you asked about. I used it on a D70 and now the D7100.

I have that exact combo: D7100 and 10-20. I have nothing but positives to say about it: most modern technology, lihjtweight, compact, shark and relatively inexpensive. You won't be disappointed. [I haven't had it long enough to say how durable it will be long-term.]