ところ and ばかり: stages and recent completion
Changing the verb before ところ changes the stage: about to start, in progress, or just finished. Compare these stages with the sense of recency in たばかり.
Just before starting and while doing
今から夕食を作るところです。 says that the speaker is about to start making dinner. The dictionary form 作る before ところです places the action just before its start, not already in progress.
夕食を作っているところです。 says that dinner is being made right now. Put the whole progressive form, 作っている, before ところ. Whether an action has started can matter when answering a call or arranging a meeting.
Something that has just finished
夕食を食べたところです。 reports having just finished dinner. The た-form before ところです places the end immediately before the current point. Compare it with 食べるところ and 食べているところ.
ところ also has a literal meaning of place, but here it refers to a stage of an action. Do not translate the phrase word by word as 'the place where I ate'; relate it to a question about when the action happened.
Recency as judged with たばかり
先月この町に引っ越したばかりです。 can say that the speaker moved here only last month. With たばかり, the speaker treats the event as still recent; it is not necessarily restricted to a few seconds ago.
電話を切ったところです can report having just ended a call. Do not memorize a fixed number of minutes to separate たところ from たばかり. Distinguish an immediate post-action stage from a period still regarded as recent.
Check: Has the reading finished in 今、資料を読んでいるところです?
Show the answer and why
The reading is still in progress. 読んでいるところ is the ongoing stage; 読んだところ is just after finishing. 読むところ would be just before starting.