I once made a confession and mentioned to the priest that I had seen some images on the internet with female nudity, but that I had not consented to any impurity. He considered it a mortal sin without making any further inquiries.

He said as an example that if a woman in a bikini pops up and I click on it, I am already commiting a mortal sin.

I discussed it no further and simply accepted what he as saying.

But I have read a lot of old, pre-council Moral Theology manuals, and they all say that immodesty is different from impurity. I mean, I can look at a nude woman and not commit a mortal sin, if it is not a proximate occasion of sin to me and if I don't consent to any impurity.

It is always a mortal sin to put yourself in a proximate occasion of sins of impurity, this much I know.

The issue is that there are degrees to remote and proximate occasions of sin, and it largely depends on the individual and the circuмstances.

My take is that the priest is being a rigorist, or is being overly simplistic because he probably thinks that I don't have a deep Moral Theology understanding.

It is obviously better not to look at nude people, but I think that it is important to be able to differ mortal and venial sin.

This is annonymous because I think that it is inappropriate to disclose our confessions.

I would appreciate comments and discussion from people who have a deeper knowledge of Moral Theology.

I mean if you watched a movie and there was nudity, would that be a mortal sin if you wanted to finish the movie? 

Every browser comes with free popup and porn blockers that you can enable. You're using this as an excuse to willingly look at pornography. Shame on you.

Is this really the case? Some websites I go to for news have a risk of people randomly posting porn in the comments, making it an occasion of sin. Even if I scroll past it would it be a mortal sin?

Why can't you choose better quality news sites?

I once made a confession and mentioned to the priest that I had seen some images on the internet with female nudity, but that I had not consented to any impurity. He considered it a mortal sin without making any further inquiries.

In defense of the Priest, most often he will not have the time to try to extract every detail and nuance; when you bring up something touching upon impurity he's likely to assume that you are bringing it up because it was a mortal sin and that you are having trouble clearly expressing it as such.

 It would be better for a man to never know what's going on in the political or economic world than to lose his immortal soul because of a need to look at websites that have immodest content.

I believe I have read that very immodestly dressed or nude women (in this case, pornography) are always going to be a proximate occasion of sin for men because the proximity is "absolute", i.e., the vast majority of men will generally fall into mortal sin on that occasion. 
That is why I stopped using 4chan, even the "safe for work" boards, because you could always count on at least one degenerate to post immoral pictures/videos

Yes or sometimes jews or discord trannies will spam post porn. Very frustrating as 4chan is more useful than majority of website on the modern internet.

  Even so nobody needs 4 Chan, 8 chan, 16 Chan, million Chan....these are excuses to read and view adult content and play innocent.

Some of us enjoy anonymous posting because we get to judge the idea of something not based on respect of persons but solely from the idea itself.

Does anyone know how to block specific website? I am unsure how to do this. If I can block 4chan it will stop be from going to it out of habit, the extra barrier should be enough to help.