Advise on new binoculars

[Tweedledee]

For an F7.5 scope your calculations are spot on.

 

In reality, because we are talking biological stuff (your eyes), things can be quite variable as to when the astigmatism actually becomes visible or is a problem. The graph is just a guideline, so experimentation might show a slightly different picture and you may be able to use larger exit pupils than expected without glasses. Experimentation will soon let you know roughly where you're at. You could also find that the visibility of the astigmatism varies slightly at different times, becoming more or less of a problem. If your eyes are tired or get a bit strained after a long observing session, this and other factors may mean you need your glasses at a smaller exit pupil some nights.

 

The Dioptrx is a great idea and and might be a good way to go, but could get expensive if you end up getting a full set of Televues. But you might like that idea. ?

[djpaul]

Well to be honest i've not had a really good night out with my scope for a while .

Maybe this weekend will be good.

At the start of my sight problems i was told at the hospital that the surface of my Cornea looked like bubble wrap.

And my sight has been getting better little by little over the past year.

So in the last 14 months its been a god send and is now smooth again.

Ive always had an astigmatism but it was corrected with contact lenses ( which i wont wear again now )

Ive only used binoculars recently and thats where i noticed the issue.

But last time i had a night out i remember the 17.3mm being fine.

I will put a report on here when i have had a good night observing with and without glasses 

 

Paul

 

 

 

 

 

[Tweedledee]

So pleased your sight is improving Paul, I remember your previous post about the nightmare you had after using the contact lenses. ?

 

All positive stuff that the 17.3mm Delos at 2.3mm exit pupil looked fine. ? ?

 

Stick with quality long eye relief eyepieces like the Delos and that will also help keep eye strain and aberrations to a minimum. Don't want to be squinting through a tiny eye lens with your eye nearly touching the glass, that just makes observing hard work.

 

[djpaul]

Quick Observation this evening

 

So after working tonight i managed to get setup for a quick test at midnight on what eyepieces i would need to wear my glasses.

Using Jupiter to observe i obviously needed them with my 32mm Panaview and i was shocked just how good this eyepiece is for its price

Then i tried my Delos 17.3mm , which i thought looked fine, untill i then put on my glasses and refocused.

Which showed one of the moons very close to Jupiter. ( which i hadn't seen without glasses )

Also the bands were much much clearer.

Using my 10mm Delos and 7.5mm Tak were absolutely fine without glasses.

I didn't bother with the Televue zoom as i now know it will be fine.

 

Once again a big thank you for everyones help and i'm looking forward to some clear nights to observe Saturn next time.

 

Paul