I did the same. Is it wrong in English or "всё" is referred only to "saw"?
Увидеть is a perfective verb.
You can use увидеть to mean the act of registering something visually. You might have heard that perfective verbs are essentially about the localisation of an action in time, associated with a transition point between two states (e.g. «заснуть» to fall asleep: not asleep → asleep).
With увидеть, you go from not seeing something to seeing it. To arrange actions into a sequence, you need a string of perfective verbs.
- you can, actually, use "видеть" in this sentence. It would mean that видеть is a framing action (you were in a state of seeing everything, and made notes of it when you had time)
- you can also use the imperfective записывал—then the actions are not localised at all. Such a sentence would mean that you habitually wrote down everything that caught you attention (during the time period you are talking about).
I'm still quite confused. This concept does not make any sense for me neither in Spanish nor in English.
If I say: "I saw a cat yesterday" I am obviously implying that before that moment I wasn't seeing it, the important information is that I saw a cat as opposed to not seeing a cat. There is no common use that I know of for this sentence that would imply that I saw a cat but I was seeing the cat before. Usually "I saw a cat" implies a transition "before I didn't see a cat" and then "I saw it".
While I can understand it (kind of, read "ok I believe it if you say so") with some verbs (like write/write down) with others it does not make any sense to me. I may be missing something important, though. Can you please explain how would the phrase be different from a practical point of view if I used the imperfective verb? Meaning,...I saw everything but I was seeing it already so then I wrote it down? Because it really does not make any sense to me :(
I think 'perfective see' corresponds more to 'notice' in English. Of course every action has a beginning and an end, but when you use a perfective verb, you put the focus on the transition point. The same way when you use 'notice', you use it to emphasize the fact that you didn't see it before. Does this help?
I'm absolute beginner, so I just offer my interpretation. If you say " I saw a cat yesterday", you clearly confer to the action a perfective aspect: a short action in a precise time. But if you say "I used to see cats", you mean a repetitive action not localized in time: you saw cats regularly every time you got out in the street. This is an imperfective aspect. These aspects,in many languages, are expressed by different tenses of one verb; in Russian there is one past tense and different verbs for each aspect.
Написать is the more-or-less neutral perfective of "write". It means scribbling words on paper or typing them (or creating music; in Russian писать also extends to painting with oils).
Записать is "to record", "to write(note) down". That's quite a good correspondence. When you record something, you do it to store the information (and then you can access that indormation later). It is also applicable even if you are not the source, the author of said information; you can "make notes" of someting another person told you, but you can hardly say that you "wrote" it.
In English, "to write down" carries with the idea that you are taking careful note of the source of what you're writing, and you are making a strong effort to record it accurately - even if the source is the thoughts in your own mind. "Mozart wrote down the music that he had composed in his head" "As Mozart lay dying, Salieri wrote down the music that Mozart was dictating to him."
No because "everything you saw" does not necessarily equal everything there is too see... to be more clear let's take an example: a thief is stealing a car. If you saw everything that would mean that you saw the whole process of theft, but maybe you just saw the fleeing part, if you only saw the fleeing part you can say "iwrote down everything i saw" and that would mean that you wrote down the fleeing, but the fleeing does not equal the whole process of theft.
Sorry for the long answer.