To snap (a photograph) = to take a photograph.
A snapper = someone who takes snaps.
"Michael placed a hidden camera in the female changing room."
Someone who takes photos or makes film and tries to hide this fact may be described as doing this surreptitiously.
Surreptitiously = In a way that attempts to avoid notice or attention; secretively.
"Mary surreptitiously slipped from the room."
To snap (a photograph) = 写真を撮ること
A snapper = 写真を撮る人
例文
"Michael placed a hidden camera in the female changing room."
マイケルは女性の更衣室に隠しカメラを仕掛けた。
写真や映画を作り、このことを隠そうとする人は、こっそりとすると表現することが出来ます。
Surreptitiously =気付かれないように、注意をひかないようにする様子。こっそりと。
例文
"Mary surreptitiously slipped from the room."
メアリーはコソコソと部屋から出ていった。
"He slyly took a photo of her" -
To be "sly" means to have or show a cunning or deceitful nature. Also, deceiving people in a clever way in order to get what you want. This sentence means that he intended to take a photo of her secretly and that he was successful because he did so slyly.
Using the word "sneakily" would also be correct since this means doing things in a secret and unfair way especially when you do it without telling anyone or when you should not really do it
"He was slick in the way he took the photo." -
For something to be "slick" means for it to be done in a smooth or efficient way. In this sentence this can mean that the photographer took the photo he wanted in a smooth and efficient way, namely to hide the camera away so as soon to attract attention to himself and what he was doing.
"A peeping Tom." is a phrase used for a person who derives sexual pleasure from secretly watching people undressing or engaging in sexual activity. This person can then takeout a step further and document this by taking photographs of women undressing or naked.
"He slyly took a photo of her" -
"sly"でいるということは、狡猾に欺くことを示しています。
また、ずるがしこい方法で人を欺くということはあなたが欲しいものを手に入れるためです。
この文章は彼が彼女の写真を内緒で撮りたがっていて、ずる賢いので成功したということを意味しています。
"sneakily"という単語を使うと、何かを内緒で行うこと、特に誰かに何も言わずに、本当はすべきではないことを不当な方法で行うことを意味しているので、これも正しいです。
"He was slick in the way he took the photo." -
何かに対して"slick"でいることは、順調に効果的な方法で何かを終えるということを意味しています。
この文章では、写真を撮った人が望んでいたものを順調に効果的な方法で撮ったということ、つまり、注意をひかずに素早くカメラを隠したということを意味しています。
"A peeping Tom."
これは、服を着ていない人や性に関することをこっそり見ることで性的な興奮を得る人を表すのに使われるフレーズです。
この人は服を脱いだ、または裸の女性の写真を撮ることによって記録して、さらに一歩を踏み出す可能性があるでしょう。
"Peeping Tom" thats basically it, there is no other way of describing this person. Since it is for immoral purposes. A peeping tom is a person that finds sexual satisfaction watching other people get undressed and or having sex. All these people have mental health issues and are very dangerous.
Using words such as "hidden" and "secretly" implies that the other person(s) don't know. You can also use words like "slick" or "sly". There are also persons who their job is to take pictures in this way. They usually take pictures of celebrities and they are referred to as paparazzi.
Being "sneaky" means to sneak around or to act without others' knowledge. "Pic" is short for "picture" so a "sneaky pic" is good way of saying to take a photo without someone's knowledge.
"Candid photo" also means the same thing; however, a candid photo is often something welcomed as it captures a more natural pose. For example, at a wedding, photographers often try to get candid photos of the bride and groom and guests.
"Without consent" means that the person in the photo did not give permission for the photo to be taken and/or used.
It is not right to take a photo of someone without their consent.
Snapping a top secret photo without someone noticing is not a done thing!
Secretly taking a picture of someone is really bad!
You need permission before taking a photo of someone. If you do not get their consent, you are in breach of the Privacy Act.
Taking a photo of a person on the sly shows poor character.
盗撮という単語自体英語にはないので「内緒で写真（ビデオ）を撮影する」というように英語にするときは言い換える必要があります。
These photos were taken non-consensually.
これらの写真は同意なく撮られたものです。
He secretly took a photo of his ex-girlfriend.
彼は元カノの写真を内緒で撮影した。
A: Do you think he was a spy?
B: Maybe. I saw him trying to sneak taking photographs.
A: 彼はスパイだと思いませんか？
B: 多分。盗撮してるのを見かけました。
英語には「盗撮」のような便利な一言がないため、taking pictures without permission（無許可で写真を撮ること）や taking secret pictures（写真をこっそり撮ること）と言わなければいけないです。
例）
The man was arrested on suspicion of photographing women secretly
男性が女性の盗撮の容疑で逮捕されました。
The celebrity complained of being secretly photographed while on vacation
その芸能人が旅行中で盗撮されたことについて不満を言いました。
ご参考になれば幸いです。
He took some underhand shots without her permission.
He sneaked in a few shots without her knowledge.
The word sneaked implies sly and deceitful behaviour.
The victim is often unaware of what has happened
until it is too late.
He took some underhand shots without her permission.
Underhand also implies that, by not asking permission first,
he acted in a cunning and immoral way.
He sneaked in a few shots without her knowledge.
彼は、彼女に気づかれずにこっそり写真を何枚か撮った。
sneakedとはこそこそ、人を騙す行為を意味します。
The victim is often unaware of what has happened until it is too late
被害者は多くの場合、手遅れになるまで何が起こったか気づかない。
He took some underhand shots without her permission.
彼は、彼女の許可を得ずにこそこそ写真を撮った。
Underhandも、許可を得ずに、こそこそするモラルに反する行為を意味します。
a) He took a photo of her without her consent
*Consent -give permission for something to happen.
"he consented to a search by a detective"
b) He secretly took pictures of her
*Secretly -in a secret way; without others knowing.
"the two were secretly married in 1751"
c) He took a photo without her knowing
She did not know he was taking pictures of her / She was unaware that he was taking pictures of her
I hope this helps ! :-)
a) He took a photo of her without her consent
彼は彼女の同意なしに彼女の写真を撮った。
*Consent -何かをするのに許可をとること
"he consented to a search by a detective"
彼は、探偵の捜査に同意した。
b) He secretly took pictures of her
彼は密かに彼女の写真を撮った。
*Secretly -密かに、気づかれずに
"the two were secretly married in 1751"
その二人は1751年に密かに結婚した。
c) He took a photo without her knowing
彼は、彼女に知られずに写真を撮った。
She did not know he was taking pictures of her / She was unaware that he was taking pictures of her
彼女は、彼が彼女の写真を撮っていたのをしらなかった。/彼女は、彼が彼女の写真を撮っていたのに気が付いていなかった。
英語には「盗撮」を一言で表す単語がありません。
「盗撮」は文章で説明しなければなりません。
【例】
"He took photos up a woman's skirt."
〔直訳〕彼は女性のスカートの中をカメラで撮りました。
〔意訳〕彼は女性のスカートの中を盗撮しました。
この文は「彼は女性のスカートの中を盗撮した」という意味です。
最近はスマートフォンを使ってスカートの中を盗撮する行為が海外でも問題になっています。
ご質問ありがとうございました。
If you want to explain that someone took a photo in way that other people couldn't see, you can say:
"He sneakily took a photo."
"He secretly took a photo."
「こっそり写真を撮った」は次のように言えます。
"He sneakily took a photo."
"He secretly took a photo."
（彼はこっそり写真を撮った）
「盗撮」を完璧に英訳はできないが、一番近い "フレーズ” は non-consensual photography です。non-consensual は承諾してないという意味で、photography は写真のことです。
例文：
Non-consensual photography is a crime.
盗撮は犯罪です。
又は without consent ともいえます。これも承諾してないという意味です。
That man took a girl's photo without her consent.
あの男は女の子を盗撮した。
日本語の「盗撮」が英語でか「Taking photos in secret」か「Voyeurism」といいます。
以下は例文です。
社会問題でもある盗撮です ー Voyeurism is a big social issue
電車に乗っているときに、盗撮に注意する必要があります ー You must be careful of people taking photos in secret on the train
参考になれば嬉しいです。
Photos taken in secret, being a voyeur is evil, stop it.
盗撮 voyeur, un-consensual photos
警察は盗撮者を逮捕します。
Police will arrest anyone who is a voyeur.
盗撮は非常に悪い習慣です。
Voyeurism is a very bad habit to have.
秘密裏に撮影した写真は、盗撮あることは、
それを停止し、悪です。
Photos taken in secret, being a voyeur
is evil, stop it.
the most common way to refer to a person who does this, is to call them a peeping tom. this includes somebody who takes photos without consent, tries to look into the window of somebody who is changing or somebody who would steal items of somebody for sexual satisfaction.
When someone takes a photo of someone/something in a way that people can't may be reffered to as:
-secretly taking a photo
-sneaking a photo.
You may use the above phrases in the following ways:
-Secretly taking a photo of a person is wrong because you are doing it without their consent.
-Sam tried to sneak a snap of his employee when he was stealing from the cash register.
"Sneaky" and "sly" are both very similar in their meaning, when something is done usually without consent and in a secret and cunning manor.
"I took a sly Photo without them knowing".
"I was very sneaky getting into my house so my parents didn't see me".
"Peeping Tom" is the expression given to someone who takes photos of people without their permission, usually these photos are off a adulterous demeanor.
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