The cost of each telescope depends on the Subscription Plan you are currently on.
The link, below, breaks down that cost site by site - please keep in mind that these rates do not list moon discounts and are subject to change upon review.
The following rates are in points cost per telescope session/hour. Meaning that for every hour of time used (or exposures taken), each telescope will cost the listed number of points for each available plan.
(1 iTelescope point = USD$1)
Please visit this link for the current plan and telescope rates:
https://pricing.itelescope.online/
Please note;
e.g. a Plan-40 customer using T21 for 2 hours of exposures will be charged 152 points
a Plan-40 customer using T21 for 2 hours of session time will be charged 104 points
(less any discounts applicable at the time)
At the end of every session log is expressed a 'system efficiency' number. This is simply the ratio of the exposures taken to the time required to capture those exposures.
e.g. for T21 it is typically 0.7; so for every 1 hour of session time around 42 minutes of images are captured
(the rest of the time is required for slewing, plate solving focusing, etc.)
Some observing plans, with high system efficiency e.g. single target, few filter changes, no 'Advanced Imaging Options' may benefit from session billing.
Observing plans with multiple targets, mosaics, possible roof closures, fluctuating temperature conditions, may benefit from using exposure billing.
It is up to each individual to determine which billing method suits their needs best.
The default billing option is 'session billing'.
It is recommended to use the 'Exposure Billing' option to determine, ahead of time, the rough cost of a session.
Please note that this is only approximate and will vary depending on your observing plan.
To select a fixed cost, ahead of a scheduled observing plan, please choose the 'Exposure Billing' option;
(Please note that scheduled reservations are only 'place holders' and will not limit or end your observing plan)
To determine the approximate time an observing plan will take to execute, please use this formula;
reservation time = 20 minutes + total exposure time + (no of exposures x 1 minute)