Difference Between Photographs And Snapshots

The difference between photography and snapshots is that a photograph contains artistic elements and it has some dependency on the photographer’s technical skills; whilst a snapshot is just a visual record of an object in front of the lens. Nowadays, the cameras has automatic functions that help largely with the technical bits, but the artistic element has to depend on the photographer.

The majority of the pictures taken each year are snapshots, and billions of them are produced annually. Actually snapshots are pretty valuable. They are very meaningful especially to the people who took them, those who are in the shots, and to their relatives, friends and family. Snapshots provide records of wonderful places, people and events, of this planet’s life as seen by people who are living it. A photograph, however, connects with an even wider variety of audience, because it looks nicer artistically, and most of them carry a message, which hits home with a universal truth. In the world of photography, there is still a lot of space for both, although the difference between photographs and snapshots still stands. Basically, there’s absolutely nothing wrong if you liked taking snapshots and is perfectly happy with it.

Whether it is photographs or snapshots, they have a few common elements which you need to know to improve your camerawork. Below are some points for photography for your knowledge.

Firstly, photography has changed from a professional practice to a much easier and portable practice. Nowadays, taking snapshots with a camera is much simplified. Secondly, Photography is a form of art as well. Thirdly, the camera serves as a tool for us. We are the people who make a difference in the shots, whether it is a poorly taken one or a good shot. Lastly, if you practice enough, you can take better photos too, whatever the subject is.

This is the difference between photographs and snapshots. When taking a good photograph, there are a lot of elements to bear in mind. These elements include your method of lighting, whether they are effective, your subjects, whether they are interesting, if not, how you turn them into interesting photographs with your skills. The composition of your shots is an important element as well. Practice makes perfect. With adequate practice, you will be able to produce quality photographs instead of snapshots.

Oracle Snapshot Too Old Intricacies

If you think you can fix oracle error “ORA-01555: snapshot too old” just by increasing the rollback segments, think again as reading this article may potentially alter your opinion.

The article explains the inner details about this oracle error, indicates the possible course of action and provides details on how to fix or avoid this error. It also explains with an example scenario that the best solution for ORA-01555 error is tuning application logic rather than adding more rollback segments.

ORA-01555: snapshot too old: rollback segment number string with name “string” too small.

Cause: rollback records needed by a reader for consistent read are overwritten by other writers.

Action: If in Automatic Undo Management mode, increase undo_retention setting. Otherwise, use larger rollback segments Details: There are number of reasons for the ORA-01555 error. The most common reason is that the rollback segments are too small. Rollback segments are used by the Oracle for reconstructing the read-consistent snapshot of the data. In Oracle during the DML operations for any changes to the data records, a snapshot of the record before the changes were made is copied to a rollback segment.

After transaction completes, its data is not deleted from the rollback segment. It remains there to service the queries and transactions that began executing before it was committed. This may cause problems with long queries because these blocks may be overwritten by other transactions, even though the separate long-running query against those blocks has not completed. So ORA-01555 error may occur whenever a long-running query is executed at the same time as data manipulation transactions.

How to avoid/fix this error :

o Augment the size of all the roll back segments.

o Add more rollback segments.

o Augment the ‘OPTIMAL’ size of the roll back segments.

o Tune the application to “commit” more frequently such that smaller rollback space is used and this condition can be avoided.

o Follow the Oracle recommended ‘proper’ solution: schedule long-running queries at times when online transaction processing is at a minimum.

Example:

ORA-01555 Error Scenario: Sample application logic causing ORA-01555 error:

  • Prepare a select
  • fetchrowArray
  • while the row is not null
  • update the row
  • if nrows mod commitsize then commit
  • fetch the next row
  • end while
  • final commit

This application logic was implemented using Perl, DBD, DBI and oracle. It raised the error as shown below:

DBD::Oracle::st fetchrow_array failed: ORA-01555: snapshot too old: rollback segment number 15 with name “_SYSSMU15$” too small (DBD ERROR: OCIStmtFetch) [for Statement ..]”

Analysis and Resolution:

As you can see from the application logic, the rows selected by the outer select query are being modified by the update statement. ie both are acting on the same table . It can be resolved by setting UNDO_RETENTION appropriately large enough BUT it may not be the best solution.The better solution may be separating out select and updates in to different transactions. After rewriting the application logic by separating data selecti and update activities, the user didn’t experience ORA-01555: snapshot too old error any longer.

How to Take Photographs Instead of Snapshots

What is the difference between a snapshot and a photograph? The thought process taken before the shutter button is even pressed.

Snapshots are taken with no thought to composition, lighting, subject matter, and no thought to intentions of what to do with the images once they have been taken.

These are some tried and true ways to being turning your snapshots into photographs:

  • Clearly identify your subject
  • Is it the birthday decorations, the birthday presents, or the birthday child
  • Understand your subject
  • Balloons move, presents can have sparkly and reflective ribbons, children move around
  • Have an idea on how you will set up your composition
  • Where do you want the child to be in relation to the cake when blowing out candles
  • Realize your lighting conditions and how they will affect your exposure
  • Do need to set custom WB? Can you dim the lights for birthday candles? Will you need a tripod if the lights are dimmed? Do you want depth of field? Do you want to show motion?
  • Edit in person – Remove unwanted items out of the foreground and background; don’t plan to remove or fix something with editing software
  • It takes 2 seconds to move a soda can, ask someone to step an inch to the left or move yourself into the position you need to be in. It can take hours to edit a collection of photographs from a single birthday party.
  • Keep an eye on your background
  • Keep backgrounds simple and clutter free so they do not compete with your subject. Be aware of items which may “grow out of heads” or objects which could cause harsh shadows.

With just a few seconds of careful consideration, you can turn your album full of snapshots into coffee table books full of photographs.