Well actually no, mainly jpg's. Opinion still seems to be divided on this, but jpg's are fine if you are careful. The main problem people have with jpg's is deterioration due to too many changes and re-saving of the original file, it is the constant re-saving which causes the loss of quality. I never make a jpg until I have finished levels, size, un-sharp mask, captions etc.
If I am working on something over a few days or a montage then I would use tiffs or a photoshop file and only make the jpg when its finished. If a jpg is only saved once (or twice in emergency's!), then it is not possible to tell the difference between it and a tiff with the human eye - you could probably find a little deterioration if you zoom right in to 100% on screen.
The original scan and manipulation is of course very important. This is where, I believe, experience of photography/art/design comes in, always best to get someone who has a good eye and understands images/tonal ranges/colour balances etc. there are too many cheap and free scanners out there and too many business/public sector people 'having a go' People can be trained, but apptitude is vital - you can't teach tone deaf people to play the piano. Everyday you can see poor digital images: in the press, advertising, internet and archive/library image systems!
On the web front, do you mean for web pages or sending images? For pages always 72 dpi and made to measure in terms of numbers of pixels, best not to be resizing images by dragging the corner handles in a web-page designer like Front-page or Dreamweaver: bad for image quality and the digital size remains the same so for example the browsers will take a long time downloading a large file that has been resized small. This is a common mistake some designers make on the internet.
For sending files: In photoshop I save jpg's at the medium compression, size 4 settings: too much compression will destroy image quality. At this ratio a file that is, say, 16mg when open, will compress to about 800 k which is fine for attaching to emails, in fact you could attach two of this size without any problems.
Hope this is useful
Michael Kirkland
LB Hackney Archives
>>> david thomas <[log in to unmask]> 12/21 10:26 pm >>>
This approach is very interesting. I assume that this is for TIFF files.
Martin, have you got any theories about appropriate compression ratios for
material to be sent across the web (JPEGs or GIFs)?
-----Original Message-----
From: Martin Taylor <[log in to unmask]>
To: [log in to unmask] <[log in to unmask]>
Date: 21 December 2000 12:59
Subject: Re: Scanned images
From: Michael Kirkland
London Borough of Hackney Archives Department
020 7241 2886
We have a digital image system in the search-room (with low reolution images
on it) and replaced our photgrapher over two years ago with a digital
service (using high resolution images). I ahve spent a lot of time looking
into most of these issues, although copyright/repro protection is an ongoing
issue. Hope this is useful:
On the dpi front, it depends on the size of the original and the size of the
intended print. You will find that small originals will soon pixelate (and
break up) at a large print size at 150 dpi. People seem to approach this in
different ways, I tend to look at file size myself eg A5 print = 5 - 10
megabyte file, A4 = 10 - 15 mg, A3 = 15 - 20 mg, A2 = 25 -35mg. I set the
dpi to what ever will get that file size (scanning image at 100% - best not
to adjust that setting to make bigger or smaller). Some
designers/photgraphers/IT people will contest this - too big, too small etc.
But this works! We have provided a range a prints over the past two years
and customer satisfaction is 100% I studied photgraphy myself years ago and
have continued into the digital age and am confident about this.
On the charges front, we have cheap prints from the system ie the low res.
images: they are printed approx A5 size on a sheet of A4 that has the ref
nos, caption, copyright/repro warning all on it. These cost 50p for bw and
£1 for colour.
The high res. stuff is split between digital prints and photographs.
Digital prints are printed by us from the high res image on an HP/Epson
photo printer on their papers. The photographs are printed by a lab on
Kodak paper from the file which we send electronically.
The charges are £10 to make the high res image (inc handling original and
professional enhancement of image) print charges are on top, ie in-house
digital print £2.50 - £4.50 (depending on bw/colour or plain/glossy/photo
paper) for A4. Photos £10 for A4, so a new A4 photograph costs the
customer £20 all together.
Customers can also buy the digital image on floppy/CDROM/attached to email
for an extra £5, so a new image on floppy is £15 all together.
Your charges may be to cheap for what they are getting; our low res print
outs are not fantastic quality, so we make them pay for something that is.
You might be getting lots of requests because of this, so you should put
your prices up! Our customers come out with the whole range of opinions - £1
is too expensive for any print out and they want a photocopy (!) to £20 is
very reasonable, cheap even.
On the digital file issue, I agree with the comment that there is no
difference between a floppy disk and a print. I have realised that a great
many customers are buying the print in order to scan it themselves or send
to an agency. I now they shouldn't, but they do - they even scan our low
res print-outs!! (which must look terrible) and use them in their
work/genealogy programs. So they might as well have the file; it saves me
generating a print, it maintains quality and establishes more of a flexible
relationship - they are more likely to come back/make requests/pay repro
fees. They have to answer questions/sign forms and the disks are covered
with our stickers, but in the end, its all down to the integrity of the
customer, as it always was in the days before scanners.
They all pay for image reproduction, if they are students, family hisorians
or local not for profit organisations then we will waive repro fees, but the
charges are the same. Publishers/authors/property
developers/TV&media/exhibitors all pay repro fees and we have scales
depending on what it is.
So far I have been talking about images owned by LB Hackney. We always
protect copyright and refer the customer to the holder of the original.
Hope this is useful. sorry about the long email. Please give me a call if
you want more info/leaflets etc. I would be interested to know what you
decide to do
Michael Kirkland
020 7241 2886
>>> <[log in to unmask]> 12/19 10:37 pm >>>
From: Alison Drew
*** Resending note of 19/12/00 12:03
To: I0032955--INTERNET RESOLUTION
From: Alison Drew
Subject: Scanned images
We have recently purchased an A4 flatbed scanner for use in the Searchroom.
At
the moment the resolution is set at 150dpi and the quality of the images
print
ed out is excellent. At the moment we are charging 2.00 for a b&w and
2.50 f
or a colour but a number of issues have arisen in the last week;
1) Should we be offering images of this quality - customers have to sign a
copy
right form but is this a good enough safeguard?
2) Requests for copies have rocketed in the last two weeks. At present
there i
s no handling charge. Do any record offices have a sliding scale of charges
dep
ending on the number of copies requested?
A customer last week asked if we could save an image to his floppy disk. We
sa
id no but I know some offices allow this - what safeguards are in place?
Finally, do any offices charge people for taking a photograph or digital
image
even if the image will not be used in a publication?
I have looked at previous messages on the list for inspiration but could not
fi
nd exactly what I was looking for. My apologies however if this has been
raise
d in the past.
Happy Christmas,
Alison Drew
Portsmouth
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