* Image format in FH/AS, JPG or TIF?

[themoudie]

Hello,

My understanding of the difference between these two image formats:-

• The JPG format looses image definition/information every time that the image is manipulated.

• Whilst the TIF format retains definition/information every time the image is manipulated.

• When I initially file my images, outwith of a FH Project, I make additional entries into the images EXIF data fields, so as to keep image information, with the image, without using overly large file names.

The vast majority (95%+) of my images stored in FH are in the JPG format, this reduces the image file size, when compared to the TIF format file size.

By using JPG format images in the FH "Media folder", am I compromising the potential long term quality of all the images, personal, locational, documentation (e.g. certificates, newspaper cuttings)?

If the answer is positive to my previous question, I intend to convert the images that I currenty have in my FH Project to the TIF format. I understand that this will appreciably increase the FH Project file size by at least four or five fold.

Would amending the image format, within FH, require the renewal of every link between the image and data to which it is linked?

I have all my image data in FH, within the Media Project folder, there are no links to remote folders outwith of the Project.

Thank you for your time to read this query.

Good health, BillR

[NickWalker]

Personally I tend to use png rather than tiff but they are both lossless formats.

If the images you download are only provided in jpeg format then as long as you don't edit the image itself the quality will not reduce. Converting them to tiff won't improve their quality. Editing exif fields shouldn't alter the actual image as they are stored separately in the image file.

[tatewise]

I agree with all that Nick says, but just add that lossless PNG files do not support EXIF metadata.

[Mark1834]

It depends to some extent what your objectives are. I usually edit image files if required for basic de-skewing and removal of large black borders in order to enhance their appearance both on screen and in pdf reports. Where contrast and legibility are poor, I experiment with tweaking the colour balance to bring out as much detail as possible. After editing, I save as a new jpg at relatively high quality (i.e. lower compression).

If there is no visible deterioration of legibility, that’s good enough for me, as the editing benefits outweigh any theoretical loss of resolution.

[themoudie]

Nick, thank you, I was thinking to edit and then save as a TIF, so that as Mike has suggested, I can retain my image EXIF data, added at initial editing and the image then becomes "lossless".

As Mark has stated, many documents require de-skewing and edging, along with some colour balance and sharpening. I then have been saving them as JPG format, with no compression. It was this final "Save" that I thought might benifit from changing to a TIF format, but on reflection, as Mark suggests, I'll no be losing that much detail of the image. Especially, as I do not use any compression in that JPG save.

Also, changing all the document images that I have in the database and relinking them would be tedious and giving myself work, when I have more than enough data to enter at present and prefer the sleuthing part of the hobby.

Thank you all for your comments.

Good health, BillR