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X6 Edit Bitmap Image is growing in Photo Paint. (major 911 concern)

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Cobaidh posted on Sat, Apr 28 2012 17:30

I created a bitmap in draw 15" x 131" then right clicked the image and selected "Edit Bitmap". The image grew to 19" X 131"...  I did this again just to verify and got the same results. I resamled the image back to 15". This is a big concern as we process all our printed images this way. Somebody please advise.

Thanks!

Answered (Verified) Verified Answer

Top 10 Contributor
London UK
Verified by Cobaidh

Having done some more tests, the conclusion I come to is that photopaint X6 is completely incapable of behaving sensibly with any image that has a different horizontal and vertical resolution.

I don't think it is specific to an image handed over from CorelDraw. PP gets confused if you set a different H and V resolution even within PP itself.

Verified by Cobaidh

This needs to be fixed! :) Thanks!

 

 

Top 75 Contributor
Quebec
Male
Verified by Cobaidh

Hi Cobaidh!

I tried it here too...The exact same issue happens also!!!
The bitmap grows!!!!!!!!!!!! What the??? Smile

 

TetroDesign

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Top 10 Contributor
Melbourne
Male

Ronny Axelsson:
First of all, when you convert the 131 x 15" (width should always be the first value) object to a 300 dpi bitmap, you hit the 30,000 pixel limit (131 x 300 = 39,300) and therefore the resolution will be limited to 229 dpi for the width. The bitmap will be 131 x 15" at 229 x 300 dpi.

Hi Ronny,

you have answered the question. The width pixel value is changing due to the pixel limitation...and following your above explanation the width "would" decrease in relation to the height! i.e. the height is unchanged in pixel count, but the width is changed (decreased) in pixel count. CorelDraw is then converting the height to 229dpi to match the width dpi which results in its physcical width increasing. I hope that made sense lol.

Best regards,
Brian.

Brian Melbourne

Top 25 Contributor
Sweden
Male

Brian:
It would be smarter if both width and height were reduced proportionately.
I agree, at least it would be less confusing.

/Ronny

“The ability to think differently today from yesterday distinguishes the wise man from the stubborn”
John Steinbeck

Top 10 Contributor
Melbourne
Male

In light of Ronnie's great explanation...the best way to deal with this situation (if you face it on a regular basis) is to write a macro which performs the conversion to bitmap and in so doing checks that the maximum pixel width is not being exceeded. If it is being exceeded the macro would apply the max "allowable" resolution (dpi) at the physical width you require - proportionately to both height and width.

Best regards,
Brian.

Brian Melbourne

Top 10 Contributor
London UK

Ronny Axelsson:
The bitmap will be 131 x 15" at 229 x 300 dpi.

That is almost certainly the key to the answer.

Some operations, including export to bitmap, do not allow separate horizontal and vertical resolutions to be selected. One of those operations is being performed later, and the resolution in both dimensions is being taken as 229.

The obvious "solution" would be to change CorelDraw's convert to image so that if it hits the resolution limit in one dimension, it should apply that limit to both dimensions -- ie, creating a bit image at 229 x 229 dpi.

Possibly a better solution would be to seek out all the operations that presently take only the resolution of a single dimension and change them so that they use both, but that is probably a bigger exercise and still likely to overlook something.

Meanwhile, I presume that if the bitmap is created at 200 or 229 dpi the problem will not be seen.

Top 25 Contributor
Sweden
Male

Maybe, or probably, we have an answer (still want to know what you do after opening in PP though).

I'd like to add one thing, as a workaround perhaps: Do not convert to 300 dpi for such a large object. Most likely you won't need it anyway.
131" (or more than 3 meters) is quite a lot, and I doubt there could be a need for a resolution higher than 150, or maximum 200 dpi.
Your screenshot looks like a wooden texture or something, and you could probably go down to 100 or even lower for that one. Try it.

/Ronny

“The ability to think differently today from yesterday distinguishes the wise man from the stubborn”
John Steinbeck

It seems like a pixel limit would cause the image to reduce and not grow, going from 131" x 15" to 131" x 19" is increseing pixels not reducing them. Please explain.

I am saving out of PP as a Tiff for large format printing (I get better results out of PP). In this case, the higher resolution was important as we were matching a laminate and it would be viewed close up. Most large images we do are around 100-150 DPI.

Thanks

C

Top 10 Contributor
London UK

The problem is that the resolution is lowered only in the larger dimension. The shorter dimension remains at 300 dpi.

Bitmaps with unequal horizontal and vertical resolution are fairly unusual. CorelDraw can't even create one, except in the roundabout way of creating a normal bitmap and stretching it.

The problem comes when subsequent processing makes the common mistake of assuming the resolutions in both directions are the same. 15" at 300 dpi will become about 19.5" (15 * 300 / 229) if it is processed assuming that both dimensions are 229 dpi.

then why doesnt it change in CorelDraw? Whay am I able to fix it by checking the aspect ratio? In this case teh aspect ratio box "un-checks" itself. Re-checking it will fix the image...

Top 10 Contributor
London UK
Verified by Cobaidh

Having done some more tests, the conclusion I come to is that photopaint X6 is completely incapable of behaving sensibly with any image that has a different horizontal and vertical resolution.

I don't think it is specific to an image handed over from CorelDraw. PP gets confused if you set a different H and V resolution even within PP itself.

Verified by Cobaidh

This needs to be fixed! :) Thanks!

 

 

Top 75 Contributor
Quebec
Male
Verified by Cobaidh

Hi Cobaidh!

I tried it here too...The exact same issue happens also!!!
The bitmap grows!!!!!!!!!!!! What the??? Smile

 

TetroDesign
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