don't go in the wet (Monsoon season June/July sometimes in to mid August)... hot, hotter and wet.. particularly from Kansai (Osaka/Kobe/Kyoto area) south

trouble is that's when Fuji Rock and Gion Matsuri are on so that's why I always seem to find my self there at that time.

Language wise you should be able to get by with just English, it's far more widely spoken in the hospitality industry than Chinese at the moment but over the last 10 years seen an increasing number of Mandarin and/or Cantonese spoken here signs. knowing writen Chinese may help with signs as most Kanji characters have, as at least one of there readings, the same Chinese meaning, but don't expect to be able to read a newspaper! (different sentence structure, Local characters (Hiragana/Katakana) and local (Kun) reading/meenings of the Kanji characters)
Be patient with their English, outside of hospitality areas, major industries and major stores spoken english can a bit hit and miss though most people learn it at school it's more a formality and more a written thing .. they're taking the extra effort so be polite and patient.. their trying to help you (and also, maybe, practice their English)

I don't want to sound condescending but you can go a long way with just (sorry/excuse me) and Arigatou (thank you)... though once your out of the main tourist areas ... yeh good luck, I can stumble my way through most things more complex than ordering a meal or buying train tickets but beyond that I found it best make sure you have a good two way phrase book (the Lonely Planet one is OK) make sure it has the Japanese phrases in both Romaji (Western) and Japanese so you can show them the phrase if the person looks at you strange.

Photography wise? high summer packs a lot of harsh glare and even a polerising filter might not cut through the washed out effect of monsoon cloud cover.
Get up and out and shoot early, relax during mid day hours then go out again later (opening hours of temples/shrines allowing). try to add variety else you get MBT syndrome (More Bloody Temples syndrome)

Re JRail Pass...

if you are going to be almost constantly travelling it's the best value you can get though if your leaving in a week your probably going to have to get your travel agent to rush the application and delivery as they need to be sorted before you depart.
For me travelling from Tokyo to Hiroshima on the Shinkansen in stages (Fiji San, Kyoto, Kobe, Himaji, Hiroshima) and return more than made the JRail pass worth it's price.

that said I didn't get one on my last trip as I was planning to just be in the Nara Kyoto region.
So if your just planing on doing local trains then you'll probably find:
1: JRail card doesn't cover most local trains anyway.
2: it's cheaper anyway to just get a local all day ticket.


Edit: That article you linked to ( matadorstudy.com/10-japanese-customs-you-must-know-before... ) is a good basic guide - another one I'd add is as well as no tipping is No Haggling/Bartering on prices . There are exceptions to this such as in food markets and local community markets but the etiquette is complex and usually the discount is quite minimal. Some large electronic stores may _MAY_ give you a discount if, as you present your cash at the register (and Japan is still predominantly a cash society) you say something polite such as (for example) and the price is xx,xxx Yen? sometimes they will round down the price a small percentage but don't expect major savings.

actually one thing in it made me laugh.. wayback before I got back in to photography I was doing a road trip up the san-in (west coast of southern Honshu island) were they don't get many western tourists, at almost every roadhouse and restaurant I was constantly being stared at (normally quite rude and not normally done by the Japanese people) assumed it was because they don't normally get westerners until a restaurant owner told me that I had wonderful technique with my chopsticks and if I had lived in Japan for many years to be that good LOL I've been using chopsticks since I was about 6 or so with local Chinese, Cambodian, Vietnamese and Korean friends so it's as natural as using a knife and fork for me.

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