Cleanup orphaned blob data using SSMS. When Sitecore runs this process it may timeout otherwise.

CleanupBlobData.sql

DECLARE @BlobID uniqueidentifier;
SELECT @BlobID = '{FF8A2D01-8A77-4F1B-A966-65806993CD31}';

WITH [BlobFields] ([fieldid])
     AS (SELECT [sharedfields].[itemid]
         FROM   [sharedfields]
         WHERE  [sharedfields].[fieldid] = @BlobID
                AND [sharedfields].[value] = 1
         UNION
         SELECT [versionedfields].[itemid]
         FROM   [versionedfields]
         WHERE  [versionedfields].[fieldid] = @BlobID
                AND [versionedfields].[value] = 1
         UNION
         SELECT [unversionedfields].[itemid]
         FROM   [unversionedfields]
         WHERE  [unversionedfields].[fieldid] = @BlobID
                AND [unversionedfields].[value] = 1
         UNION
         SELECT [archivedfields].[archivalid]
         FROM   [archivedfields]
         WHERE  [archivedfields].[fieldid] = @BlobID
                AND [archivedfields].[value] = 1),
     [ExistingBlobs] ([blobid])
     AS (SELECT [blobs].[blobid]
         FROM   [blobs]
                JOIN [sharedfields]
                  ON '{'
                     + CONVERT(NVARCHAR(max), [blobs].[blobid])
                     + '}' = [sharedfields].[value]
                JOIN [BlobFields]
                  ON [sharedfields].[fieldid] = [blobfields].[fieldid]
         UNION
         SELECT [blobs].[blobid]
         FROM   [blobs]
                JOIN [sharedfields]
                  ON CONVERT(NVARCHAR(max), [blobs].[blobid]) =
                     [sharedfields].[value]
                JOIN [BlobFields]
                  ON [sharedfields].[fieldid] = [blobfields].[fieldid]
         UNION
         SELECT [blobs].[blobid]
         FROM   [blobs]
                JOIN [versionedfields]
                  ON '{'
                     + CONVERT(NVARCHAR(max), [blobs].[blobid])
                     + '}' = [versionedfields].[value]
                JOIN [BlobFields]
                  ON [versionedfields].[fieldid] = [blobfields].[fieldid]
         UNION
         SELECT [blobs].[blobid]
         FROM   [blobs]
                JOIN [versionedfields]
                  ON CONVERT(NVARCHAR(max), [blobs].[blobid]) =
                     [versionedfields].[value]
                JOIN [BlobFields]
                  ON [versionedfields].[fieldid] = [blobfields].[fieldid]
         UNION
         SELECT [blobs].[blobid]
         FROM   [blobs]
                JOIN [unversionedfields]
                  ON '{'
                     + CONVERT(NVARCHAR(max), [blobs].[blobid])
                     + '}' = [unversionedfields].[value]
                JOIN [BlobFields]
                  ON [unversionedfields].[fieldid] = [blobfields].[fieldid]
         UNION
         SELECT [blobs].[blobid]
         FROM   [blobs]
                JOIN [unversionedfields]
                  ON CONVERT(NVARCHAR(max), [blobs].[blobid]) =
                     [unversionedfields].[value]
                JOIN [BlobFields]
                  ON [unversionedfields].[fieldid] = [blobfields].[fieldid]
         UNION
         SELECT [blobs].[blobid]
         FROM   [blobs]
                JOIN [archivedfields]
                  ON '{'
                     + CONVERT(NVARCHAR(max), [blobs].[blobid])
                     + '}' = [archivedfields].[value]
                JOIN [BlobFields]
                  ON [archivedfields].[fieldid] = [blobfields].[fieldid]
         UNION
         SELECT [blobs].[blobid]
         FROM   [blobs]
                JOIN [archivedfields]
                  ON CONVERT(NVARCHAR(max), [blobs].[blobid]) =
                     [archivedfields].[value]
                JOIN [BlobFields]
                  ON [archivedfields].[fieldid] = [blobfields].[fieldid])
DELETE FROM [blobs]
WHERE  NOT EXISTS (SELECT NULL
                   FROM   [ExistingBlobs]
                   WHERE  [existingblobs].[blobid] = [blobs].[blobid]) 

ReportTableSpace.ps1

Import-Function -Name Invoke-SqlCommand

$database = Get-Database -Name "master"
$connection = [Sitecore.Configuration.Settings]::GetConnectionString($database.Name)

$query = @"
SELECT 
    t.NAME AS TableName,
    s.Name AS SchemaName,
    p.rows AS RowCounts,
    CAST(ROUND(((SUM(a.total_pages) * 8) / 1024.00), 2) AS NUMERIC(36, 2)) AS TotalPageSpaceMB,
    CAST(ROUND(((SUM(a.used_pages) * 8) / 1024.00), 2) AS NUMERIC(36, 2)) AS UsedPageSpaceMB, 
    CAST(ROUND(((SUM(a.total_pages) - SUM(a.used_pages)) * 8) / 1024.00, 2) AS NUMERIC(36, 2)) AS UnusedSpaceMB
FROM 
    sys.tables t
INNER JOIN      
    sys.indexes i ON t.OBJECT_ID = i.object_id
INNER JOIN 
    sys.partitions p ON i.object_id = p.OBJECT_ID AND i.index_id = p.index_id
INNER JOIN 
    sys.allocation_units a ON p.partition_id = a.container_id
LEFT OUTER JOIN 
    sys.schemas s ON t.schema_id = s.schema_id
WHERE 
    t.NAME NOT LIKE 'dt%' 
    AND t.is_ms_shipped = 0
    AND i.OBJECT_ID > 255 
GROUP BY 
    t.Name, s.Name, p.Rows
ORDER BY 
    t.Name
"@

Invoke-SqlCommand -Connection $connection -Query $query | Show-ListView