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orshulim

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photoShop cs2 when I bring in image fro digital camera itis 72 pixel to save high resolution is 300

HI
photoShop cs2 when I bring in image fro digital camera it is 72 pixel to save high resolution is 300 WHY?   Do I need to change it when cropping on the top bar?
Thanks
orshulim
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dandeliondream
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Hi orshulim,

what is the problem you are facing right now? Are you saying that you have a 72dpi photo which you wish to change to 300dpi?
Not sure exactly what you mean.. but what I'm guessing is that you are worried that the resolution of 72 pixels per inch is lowering the quality of your image.  That is not the case - the resolution is SIZE modifier, not a pizel modifier...

If you increase 72pizels/inch to 300pixels/inch on a (say) 1024x768 image it will not increase the quality of your image - it will simply change it's size (when printed) from approx 14x10inches to 3.5x2.5 inches.... (or you might end up up-sampling your image to 4267x3200 pixels - which will be more pixels but no more quality...)


This only becomes particularly important if you are mastering an image for a press/printer with a specific resolution.  If you are just talking about editing an image from your camera, then changing the resolution will have no difference to the quality of your image (jus tthe printed size-which you can change anyway in the printer dialog)

If this's not your issue, please clarify.!
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pcumberbatch

Not clear as the others have indicated, but here are a few possibilities depending on how the ? is interpreted.

If your pictures are taken at 300 or higher then you might need to set the resolution on your canvas to match before importing the image.

If you are not taking them at 300 or higher and you want that quality then you will have to take photos at the higher resolution to start with.
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HI
OK I am using casio z750  7.2m  and fujifilm f40d  8.3m at highest resolution at fine mode
the apx file size 3400* 2900 2:3 mode   when I bring it in into photoshop I see it says 72pixels now when I work on on the image and want to save it to send to the photolab  do I save it at 300pixils? do I need to change the 72 to 300 when I am editing?
Thanks
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Tom Ray
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Bottom line is... if you don't really know what to do with it - you don't need to use it at all.  All you need to know is that your photos will be exactly the same quality whether you import them at 72 or 300 ppi.

All that matters to the pictures from your digi camera is the PIXEL dimensions....

(think of resolution as simply a mutiplier that will convert pixels to inches)

Good luck..
Hi
I am still mixed up the photo lab that I use claims that in order to get a good rendition at 8*10 I need at least 5mp  because they print at 800ppi so how do I save my jpeg in pS at 12 maximum and 300ppi ?
Thanks
Don't get confused... if you import your pictures at 72 or 300dpi, the PIXEL dimensions of the image will be the same.... so the lab will not see any difference...

Your z750's maximum image size is 3072 x 2304.  It is this that makes the "megapixels" and this will not change just because you have changed the "resolution" in PS.  whether you mport this into a new document of 72dpi, or 300dpi, the image (providing you don't resample it) will still have 3072x2304 pixels and can be used by your lab.

As I said above - please ignore resolution completely - your photolab doesn't care.  Concentrate on PIXEL SIZE only (ie 3072x2304).  Your lab will take care of the rest...   So save your document at jpeg least compression (12) and totally, completely and utterly ignore the resolution.  This setting will not change the quality of your image.

your 3072x2304 image will be:
@72dpi - 42"x72" - 3072 pixels by 2304 pixels
@300dpi - 10"x8" - 3072 pixels by 2304 pixels
@800dpi - 4"x3" - 3072 pixels by 2304 pixels
@9999dpi - 0.3"x0.2" - 3072 pixels by 2304 pixels

So can you understand? the resolution only defines a physical size that the image would be for a given pixel size. In every case - whatever this is set to, the amount of information available to the lab will be the same (as would the file size) - they only care how many pixels there are.

From the data above, you can see that pixel for pixel, your z750 will produce perfect quality 4"x3" prints with an 800dpi process. In reality - with this camera you should be able to produce 8"x10" or larger without any noticable drop in quality at all.

Bottom line - forget avout resulotion - care about PIXEL DIMENSIONS..........!
Hi
Thanks But what happens when I crop the image ?
Thanks
as a side note - don't even THINK about 'upsampling' to get bigger pixel dimensions... if the data wasn't there from the camera, upsampling may actually reduce the quality of your image as it get 'interpolated'.  Make sure the pixel size of your images that are going to the lab equals exactly the pixel size out of your camera (unless you've cropped - in which case it may even be less!) - don't resize (and by resize i really mean resample) an image if you can help it....

A good way to go is to turn off the "resample image" box in the image size dialog.  You can play with the dimensions and resolution to your hearts content... and you will never change the important pixel dimensions of your print.
If you crop... best idea is still not to resample - you can't create detail that was never there!!!!!
Hi
I am still confused
1) I bring in image 3700* 3200  for example
2) I crop   AND AM LEFT WITH 40% OF ORIGINAL IMAGE
3) Save as  new.jpg
4) dialog box jums up resolution 12  maximum file
fine now what do you mean by not resampling?
wHEN I look at bottom of PS it still tells me I have afile of 22.5mb
THANKS
1) Yes
2)Yes - you are... but you are never going to get any MORE detail than 40% of the original image - upsampling (ie converting the - cropped, say 1480x1280 back to 3700x3200) will not make the image any better - in fact it is likely to be worse....
3) Yes
4) Ignore resolution entirely, save as 12 maximum jpg file

by "not resampling" I mean do not change the pixel size (other than by cropping) - you will potentially lose some picture data this way.

File size of 22.5mb is the UNCOMPRESSED size of the image.

Please clarify if you are still confused on any of these points.  If you crop too tight you will see a pixelated image because you now only have (say) 40% of your 7.2mpixel orignal.
Hi
the original image (before cropping I already worked on it and cannot go back to ORIGINAL) 8*12 by 300ppi  now if I crop regular I will still see at bottom 22.5m as before I cropped NOW if I clear the 300ppi leave it empty then I will get 10.5m
is this the way to do it ? and then save at 12 maximum?
Thanks
your problem seems to be that you may have resampled the image because you mistakenly believed that you must set the image to 8x12 300ppi - to force this will change the amount of pixels (to (8x300)x(12x300)= 2400x3600 for the cropped image.

My advice, please just IGNORE the SIZE and RESOLUTION in future - the ONLY thing that matters is the PIXEL DIMENSIONS.

If you need further advice, please describe your situation to me in PIXEL DIMENSIONS - and not inches, ppi and file size. These are not pertinent to your situation.

Thanks!
Orshulium,
Me again.  
Open the original in Photoshop.
Select the crop tool
At the top you will see the crop width x height and resolution.
Before you crop:  Set the width to 8.5in   the height to 11.5in and the resolution to 300.
Make the crop.
Save as a photoshop .pdf file if they will accept it.
If you want better photos with your camera try shooting in tiff or raw mode.
Much higher quality output with tiff or raw modes.
Jpegs are for the internet.
Thanks
I accept the advice But I would like to understand what actually happens
I open up original jpeg from my camera 4000*3000 pix at 72pix   When I crop I must input asize 4*6  5*7 8*10 ect. now it automaticlly downsizes my image  especially when I crop   so if I blank out the pix box then it will not change the resolution from original but since I left over the height and width it will increase width and height  of the crop to the original wich in that case will add in pixels and degrade the image If I do not input height and width I cannot crop properly because the crop tool turns into free crop.
Thanks
Apologies in advance vanwraps ... but as a purist,  I would strongly suggest NOT entering the reolution to be 300 in the crop.  This will force the image to be resampled - potentially losing quality along the way as the pixels are interpolated.

There are three variables here and they are related thus...

Resolution x Physical Size = Pixel Dimensions - so eg, 300ppi X 6" = 1800pixels

If you change any then the other will by definition change.... and you really shouldn't (as I've said at least once every post, care about resolution. it's simply not important for what you need.  What is most important is that you preserve the data that's in your image -and as vanwraps correctly suggested, you will keep the data in it's most preserved form if you use TIFF or RAW (but you may then need further processing in PS as RAW does not (by default) apply the white balance and other settings to the data).

If you use raw, and then change the pixel dimensions (thus resampling) you will certainly lose some of the original image data through the resample process.  It may be you don't care about that, or that you have a specific reason (eg cropping very tight, and reducing some pixellation through, say, a gaussian blur etc) -

but you will not end up with the best and most faithful reproduction of the original image data if you resample in any way at all, ever, period.

The original image data is contained in the pixel dimensions (obviously) - unchanged, these are the original pixels from the camera, millions of dots with millions of colour variations.  If you ever change this (other than by cropping), the computer has to make an educated guess as to what the neighbouring pixels should be.  This is interpolation.  It's good, but it will always result in < (or at very best = to in some special cases)  the original detail - it can NEVER increase it.

Keeping the pixel dimensions the same (as we ought to), then changing the physical size will change the resolution, and vice versa - and these two numbers are just that, numbers - they change nothing other than, effectively, a comment on the file saying how many big this picture will be phyically, with how many pixels are available per inch.

I'll say, for hopefully the last time...

"If you want to preserve as much detail as possible in your image, NEVER, EVER resample your image"

The photo shop does not give a d**n what resolution, or image size you set in photoshop - it cares only about the pixels in your image - which get scaled to whatever size you print.

Top tip though - I do use the crop tool in PS quite a lot, and I set the dimensions to what I expect the output to be - not to specifically get the size, but to get the correct aspect ratio.  I leave the resolution box blank - that way, I fix my physical size, and keep my pixel dimensions - but the resolution (which is just the variable that defines the relationship between the two) changes - to what, I don't know, I don't care, and I can't influence it anyway by any means other than buying a new camera...

Note to flamers... I know in a professional studio that this is (or MAY BE) relevant - but here, it's not, and it never will be.


Now finally, I see you have already destructuvely (ie you can't go back) resampled the image, to 8x10 300ppi (so 2400x3000).  Now, having said all of the above, the chances are that the image looks fine your your (and probably everyone elses) eye.  Just give this (and vanwraps correctly says ps pdf will be a great format to use) to you photo shop and they will print it.
Sorry - first post written before reading last post...!

You can input the crop dimensions but not set the resolution... try this.

Import image @ 4000x3000  (set resolution to whatever you like - IT DOESN'T MAKE A DIFFERENCE)

you now have a 4000x3000 image loaded in PS. Check this by going to Image > Image Size.
(ignore document size and resolution at this stage, just check pixel dims = 4000x3000)

Select crop tool.

In boxes on toolbar select width "10in" and height "8in" - make sure Resolution box is EMPTY.

crop tool will now remain fixed to an 8x10 aspect ratio.

Crop your image.

go to image > image size.

you will now see your pixel dimensions have DECREASED. This is expected as we have chopped away some of our image.  Document Size will say 8in x 10in and resultion will be one over the other (ie pixels/physical).  Again - this is unimportant - you don't have any more data to increase this - so stop stressing!!

Important thing is yes, it is possible to crop to a defined physical size without resampling!!
...if i crop a 4000x3000 image right down the middle, it will be a 2000x3000 image.  I could resample that image back to 4000x3000 - but it won't improve in quality... best action is to leave it at 2000x3000.

If you really need the cropped portion to have 4000x3000 pixels in it - then frame the photograph correctly in camera, and use appropriate zoom/lenses/distance to achieve the result you desire!!! PS rule #1 - you can never bring back detail that was never in the original
Thanks to evryone
I did an interesting test
I have original image 31*46"  by 72pixel   I cropped the image without changing the width height cleaerd the  pixel count went to image found pixel had gone down 36  Fine
Next I changed  width and height t 4*6 * 800 pixel
Then I compared both at high magnification side by side  the 4*6*800 won hands down
not only that but the original pic when compared at equal size also the 4*6*800pix won hands down the original and 36pixel cropped image all broke into pixelated much before the cropped image at higher pixels
Thanks
Now your getting it.  The crop is the very effective at changing the size, shape, perspective and resolution of an image.  
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Hi
Guys I'am convinced
By the way when A raw pictute is taken with adigital camera at what resolution is it? My camera casio and fujifilm only have jpeg's
Thanks
RAW mode, which, unfortunately, you correctly state is not available on your models, saves the image uncompressed (so no JPG compression artifacts ) in the state that it comes out of the camera - (so no 'electronic' 'in-camera' adjustments - eg sharpness, whitebalance etc)

For purists and professionals (and of course keen amateurs) this provides the most accurate image - effectively as it was captured by the CCD sensor in the camera.  You can then do the white balance and control any sharpening to your own liking using PS.

RAW files are much much bigger (and should actually be the same size as the 'image size' you have seen in PS) as they are completely uncompressed.

I wouldn't worry about all of this too much - technicalities aside... so long as your pictures look good to you and your audience... don't get too bogged down in technology, and enjoy your hobby!!!!!

GOOD LUCK and all the best!!!!!

Steve