Re: save jpg as tif before editing?

On Fri, 2 Sep 2005 08:49:47 +1000, "Mike Warren"
<miwa-not-this-bit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:

>DD wrote:
>> On Fri, 2 Sep 2005 08:12:23 +1000, "Mike Warren"
>> <miwa-not-this-bit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
>>
>>> DD wrote:
>>>> This Greg, is something important you're saying here.
>>>> It seems to be an open question whether moving JPG's
>>>> from one file to another and one drive to another, do cause lost.
>>>> This is what I've been told. What about renaming a pic?
>>>> I am not sure whether everybody agree's here.
>>>
>>> No. Any copy you make *at the file system level* is an
>>> exact binary copy of the original. There is no added
>>> degradation. The degradation happens when a JPEG file
>>> is opened and resaved.
>>>
>>> -Mike
>>>
>>
>> So Mike, just viewieng a jpeg is degrading it?
>> Opening the file, running through the pics to see what to write to CD,
>> before you resave it on CD, is degrading it? Otherwise you better be
>> sure by reading the description without opening it?
>
>You must do 2 things to cause a recompression (and quality loss).
>1) Open the file to view it. This decompresses the file.
>2) Save the file. This recompresses it.
>
>Just closing the file after viewing doesn't change the file at all.
>
>If you open a JPEG file and then "Save As" to another location
>then you are degrading it. If you just copy the file to another
>location using a file manager, no quality loss occurs.
>
>> Because if I understand you right, resaving cause no damage
>> unless you first viewed it. At least, viewing it is opening it.
>
>Degradation happens whenever a format change occurs if either
>the starting format or destination format are compressed regardless
>of whether in memory or file.
>
>-Mike
>
>
>

Thanx for making it clear.
I am alway saving in PSD
but what we discussed here, was important to know. It is a relieve
to know I can rename jpg's without losing quality.

1:15 am. See you's in the evening. It's already the 2nd here:-)

Here is something I'm working in PSD on - still batling to get
the sand colour the way I want it:-)
http://home.intekom.com/davesplace/sunrise/seagull.jpg

Thanks again; talk again later.

Dave



.

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