Photo Restoration Blog

Archive for August, 2008

The effects that over compressing a JPEG file can have on your images.

When it comes to photo repairs you may scan in an image from a print, slide or negative and your scanning software does it all for you, its simple you just hit the go button and the job is done. Have you ever looked at the settings within the software to see how the software is saving your image? or if it gives you any options to alter the way the file is saved or scanned? Saving without compression or little compression is the best way to preserve detail in your image. A JPEG file is a “lossy” format, or a format where data is discarded in order to save space when saving. The higher the compression the more data is thrown away and the less detail there will be in your image.

There is no excuse these days, when hard disks are so very cheap to save your image with any other setting other than the best. It might be worth examining the software that came with your scanner or camera and check that you do have the option to change the way it saves and what format it saves your images in. Phrases to look for in the manual or software settings are “best setting” or the “lowest compression”, “lossless format” or “large file size”. You get the idea but do look for the top setting. Try to scan you image so that the longest side of the photo ends up at around 3000 pixels long, just scan the photo not the whole scanner bed.

To do this measure your photo in inches.

• Above 10 inches set the scanner to 300 Dpi (dots per inch)
• 10 to 9 inches set the scanner to 300 Dpi
• 7 to 8 inches set the scanner to 400 Dpi
• 5 to 6 inches set the scanner to 500 to 600 Dpi
• 3 to 4 inches set the scanner to 1200 Dpi
• 1 to 2 inches set the scanner to 2400 Dpi

If you scanner manual lists its maximum optical scanning resolution then scanning above this will not really help with the final image. Any higher and the scanner will be adding pixels or data that were never there, this is called “interpolation”.We want to avoid any kind of interpolation if we want a good scan, we only want to restoring the original details not those that have been padded out by your scanner.

Saving your image.

To give you idea of what goes on when you save I have included an example below.

Sample photo that is about to saved to JPEG

It is a photo of a group of people. now let us save it at different compression ratios.

JPEG setting from 100% to 0%"

As you can see the further we go with the compression the worse the data becomes and more the image suffers. The blocks you can see in the “0%” corner are where the JPEG algorithm splits up the photo into blocks in order to save it, the more data that is thrown away the more blocks there are visible. When this happens across a detailed section of the image the detail is lost, blocks meet and slurring of colours and details occur. This is called JPEG artefacts. It is these artefacts we do not want when our software takes over and saves our images for us.

On a further note, if you do save an image in this manner and then open it and make changes to it and re-save it with the same settings then the image will just get even worse.

In order for a restoration to be carried out to a high standard then highly compressed files must be avoided!

To Summarize

1. Scan with the appropriate DPI for the size of your image (see above)

2. Scan in colour, even if your photo is black and white.

3. Save with low compression, or biggest file size in JPEG or TIFF format.

If you still have trouble with scanners and wrestling with the jargon then you may of course post your photo to me.

Image-Restore Helping you repairing old photos

Clapton Football Club and Essex County Cricket Club circa (late) 1890’s

Photo repairs performed in July 2008

Opportunities like this don’t come around too often. I had the honour to repair and restore historic images from the late 1890’s of both these prestigious teams. Clapton Football Club were one of, if not the best team in the country at the time these photos were taken.  A select 11 were chosen to represent the club for the posed photo. There were 3 main photos posed for the camera. Two of the team shot in their strip and one in suits.  Mounted on heavy card and printed on fibre based paper and processed using silver based chemicals, the quality of these photos was superb!  It isn’t until I have worked on photos like these do realise just how well the photographers did their job back then.  The photographers couldn’t just set the camera to a high ISO and snap away, they had to wait for good light and work with the subjects to keep them calm and still whilst they set up the camera and prepared for the shot.

The Clapton Football Club photo was posed with the team in their strip, which appeared to be black and white broad striped tops, which is in fact red and white. Notably in the photo there are only 11 men in stripes and today their team photo has 17 men ready and waiting along with goalies and many others.  Their shirts were tucked into their shorts which were high up the waist in line with the elbow and fastened with a cloth rope or webbing belt.  Shorts vary in length with some longer than the knee, others above the knee.  The ball was heavy leather and made of around 10 leather panels wrapping from top to bottom and sewn into a ball shape. Shin pads were heavy duty and worn outside the socks.  With the socks themselves a little un-coordinated, seemingly whatever was thick and dark and long would do.

The Essex Cricket Team shot was posed outside the clubhouse with hanging baskets dangling from the thatched roof, some children had jostled for places in the background so they could get in the picture, with one who snuck to a window as the shutter was pressed.  Heavy white woollen sweaters and thick white shirts with a dark cloth cap with cricket clubs emblem on the front was the attire.  Once again trousers were held up with silk scarves or cloth strips and their white trousers were turned up a couple of inches at the shoe.  Of the twelve men wearing whites, only one did not have a full bushy moustache and he held a pipe, all other figures who were not children were men and wore suits and bowler hats.

The photo repair that was needed was to improve the contrast, remove the mildew spots that are a tell tale sign of an old photo and to clean them of scratches and dust and grime that had built up over the last 120 years.

There is something to be said for this type of posed photo, it wasn’t mass produced, they were not taken with cheap throw away cameras like today, they taken with care and attention and were shot and printed using the best techniques of the period.  As a result they have stood the tests of time.  I feel that in the throwaway society we live in today photographs can be taken without the slightest thought and just mound up on hard drives and data storage devices, images without real meaning or value. Think hard when you take a photo, make it worthwhile and limit your shots, perhaps you will make sure you take that one shot that sums up what a week’s worth of happy snaps could never do.

NOTE: Apologies, but due to copyright restrictions I am only able to post a small portion of the photo.

Image-Restore – Photo repair for everyone!

Clapton Football 1890 socks