1) How does meditation outside effect the Jhana and Access Concentration? Internal states, mental states, emotional states, effect access concentration far more than whether practicing inside or outside. Depending on your focal point will effect Jhana, in so far as nimattas arising, plus you're using this word broadly. When you get into higher Jhanas (level depending on who you follow or interpretation), inside vs. outside ceases to exist.
Is Jhana possible in the hot sun or wind? Yes, if you are practiced since you pull your senses inwards or reoriente them internally where there is no hot sun nor external wind. If a person is undisciplined in mind, and emotionally reactive, I imagine it would be very, very, difficult.
If you do achieve it - is it technically a harder Jhana because I would presume difficulty is impacted?Harder Jhanas imhe are more of an impact from concentration coupled with mindfulness rather than an external factor such as weather. In other words, if you relate your mind to a flashlight, a hard jhana is associated to training one's mind to focus your internal mind's light to that of a laser. It cuts through the junk easier, faster, and gets deeper efficiently.
Walking Meditation and Jhana. Can you enter the first Jhana while doing walking meditation? Yes, and further Jhanas as well, but it does get difficult to balance walking once crossed into fourth Jhana, I tend to stop and stand, put the body on hold at that point though, I imagine others would have different experiences though, so not saying my perspective is all inclusive.
How about with eyes open? Yes.
How about with eyes closed? Yes.
How about with eyes partly closed?Yes.
What are the differences between the after image(outline) created when staring at an object for a duration of time and then closing your eyes?
With eyes open(or closed or partly closed), I find the nimatta will arise and overlay the afterimage/outline, the same happens when observing breath(or any physical object), one shifts from the physical focal point to the soft hazy image(not afterimage), then another brighter, luminous point will stabilize and shift to that point.
Versus the after image that arises natural within the mind - fractal geometry and almost seemingly random objects that will suddenly materialize when you have your eyes closed? Are you referring to the images that arise in deeper jhana states where there are luminous, bright, textural images? Or the dream-like objects that may arise when in a light state? Personal immersion will really help you discern, especially if your mind is bright and clear, there is alot of differences, in texture, clarity, etc. There is a congruencey that arises, architypical images if you will so that it's easier to establish a path, know where others are and where you are in these states.
These objects seem to instantly drop you into access concentration... or are a result of Jhana and access concentration - not sure yet...I recommend some more practice, and observation, or perhaps reading from a favorite pro may help. It seems like a chicken vs. the egg type question, do these objects cause access concentration or does access concentration cause the objects, which came first? When practicing and establishing yourself in your path/method, it helps to go in, then back up, back and forth to help you learn how to navigate readily and the questions will be answered just from do that.
The first jhana - has anyone experienced these variations of it? Variations may occur do to preinclinations, object, and practice. Why some teachers like to have their students all focus on the same object(breath) as it removes some of the variables and helps the teacher, help the student efficiently.
Sometimes I will experience total bliss, another time I have experienced no body sensation, but did drop in the first jhana, another time I swear I dropped into Jhana, but experienced pain, another time I experienced a very dull sensation - almost like a bliss sensation that was incomplete.
I tend to skip the bliss out, and hop right into the deeper states. Pain is also a general term, if you meditate on a wrathful deity, and drop into a deep Jhana you may feel pain too, but it's different than say, your bum hurting or knees aching.
There's a compilation of various experiences many meditators experienced in meditation, if you'd like I could locate it, but it basically gives an idea of how variable sensation even emotions can be. It does help to talk to a community in that regard though. Fun questions though. Also, enjoy your retreat. I had an online meditation teacher who really helped me get established, though he doesn't do that anymore, I highly recommend the experience.
