Query user logins using distinct and report back daily, weekly and monthly usage

I have a simple SQL Query, that I'm looking to report back site usage hourly, daily, weekly and monthly.
I require the query to use Distinct as the nature of the application will create several entries to the table upon a each new login to the site.

Here is what I have so far:

SELECT  DISTINCT OPRID,
CONVERT(varchar(12), LOGINDTTM, 112) 'Date'
from   PSACCESSLOG_HIST
where  OPRID NOT IN ('AUTOPROC', 'PSAPPS', 'PHSADBA', 'PTWEBSERVER')
ORDER BY Date

This will give the following:

OPRID     LOGIPADDRESS     LOGINDTTM      LOGOUTDTTM
dadams     10.1.1.5        20130612        20130612
jblake     10.1.1.5        20130614        20130614

First I do need to group the data as mentioned above by day. This is what I'm looking for, for this part:

LOGINDATE-TIME    TOTAL-LOGINS
20130612           25
20130613           35
20130614           45

Appreciate replies