Sony a200 DPI

mattjames

mattjames

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I have been asked to supply some pictures to a magazine. They want the pictures to be 300 DPI. Im using a Sony a200 camera, if I have the format set to FINE then when i look at the images on the memory card they are only 72 DPI. If i set the format to RAW they are 240 DPI. Does anyone know if i can get the Sony a200 to produce 300 DPI shots?
 
To take them off of the card I just copy and paste. I use Picassa to go through and crop them. I do have Photoshop CS3 but and still getting to grips with it at the moment. When I look at the images on the memory card before I have even taken them off and select properties it says the DPI is 72 so i just assumed that was what my camera was taking them at.
 
First all I feel obliged to point out this post... http://www.talkphotography.co.uk/forums/showpost.php?p=1976386&postcount=63

;)

If your camera can only produce 72DPI JPEGS I would shoot RAW, when you use the RAW processor you can set the DPI before you open it in photoshop to edit. If you want to change a JPEG then go to "Edit > Image size". Be aware that if you change the DPI you should reduce the image size or you will be interpolating the image and reducing the quality. You can get away with quite a bit though :)
 
Thanks for your reply. I have to say its for a charity magazine that dont pay for work so im not really pushing in i feel.

I have taken a shots in RAW format, what would be the best way for me to take these off of the memory card?

I have some software that came with my camera and that has a RAW convertor with it but all it does is save the RAW image as a jpg at 72 DPI, am i missing something?
 
Thanks for that link, I used that convertor to open the .ARW file and it lets me adjust all the bits, It does say that its 240 DPI so im guessing that the Sony a200 does not shoot any higher than this?

When i save the file out of the converter which would be the best format to use, i normally use JPG but was not sure if any others would be better?
 
The dpi is only for printing.
Your camera just loads the pixel data, it does not load at 72dpi, 300dpi, or any other dpi.

The picture data may be, for example, 3000 pixels by 2000 pixels, if you want a picture that is 10 inches wide then you need to print at 300 pixels per inch, or 300ppi (or confusingly dpi in some software) as 3000 pixels/10 inches = 300ppi.

The software just puts a default figure in the ppi/dpi box. A lot of software still put 72ppi/dpi as AFAIK this used to be the standard monitor pixel resolution, therefore it gave an idea of the size the image would be on that standard monitor. Other software may stick 300 ppi/dpi in the box.

Nowadays monitors have different resolutions and different pixel sizes so ignore the dpi/ppi figure for everything except printing.

The above ignores resampling, this can reduce or increase the number of pixels in the picture data and would allow you to print, for example, a 3000 pixel picture 20 inches wide at 300ppi/dpi.
 
Thanks for your continued advice. A lot of the technical stuff goes right over my head but im trying to take it all in.

For me to provide an image to a magazine that is 300 DPI what would you say is my best method?

If i shoot the picture in RAW does it give you a better qualit shot than one shot in normal? or is RAW just about giving you extra editing options?
 
DPI should really be PPI or Pixels per Inch, however as your software is using DPI I will continue to use that term.

300 DPI means that the image, when printed, will have 300 dots (pixels) for every inch. If the printed image is 10 inches wide then the supplied image has to be 3000 pixels wide (3000/10 = 300). If the printed image is 5 inches wide then the supplied image has to be 1500 pixels wide (1500/5 = 300).

You need to know what the size of the final image will be, you can then supply an image with the correct number of pixels.

Printed Image width (inches)/300 = number of pixels width.

It can be confusing until it suddenly clicks!

Imagine a tile mosaic on a wall, it is 30 inches wide and 20 inches high.
Each tile is 0.5 inches square. There are therefore 60 tiles by 40 tiles, or 2400 tiles in total. The resolution is 2 tiles per inch or 2 TPI.

If you want the same mosaic but larger and still use 2400 tiles you have to have larger tiles eg. for a 60 inch by 40 inch mosaic you will need tiles that are 1 inch square. The resolution is now 1 TPI.

If someone wants a resolution of 3 TPI and a mosaic that is 45 inches wide by 30 inches high you have to have 135 tiles by 90 tiles or 12150 tiles in total.

If they just say they want a resolution of 4 TPI it does not help at all, they need to also tell you the final size that they want or how many tiles in total you can use.

Not sure if the above will confuse you more but I hope it helps :)


As for raw, in simple terms raw gives you better editing options.
When you want to print, or display, raw you convert to jpeg anyway.
 
Suvv said:
You need to know what the size of the final image will be, you can then supply an image with the correct number of pixels.
Click to expand...
Absolutely. If the magazine just said 300 DPI and gave you no other guidance, then they don't know what they're talking about.
 
Thanks for that, it kind of makes sense but i seem to have read so much today that my brain has turned to mush. They said that they want images that are 1500 by 1000 at 300 DPI.

The thing that confuses me is this, I always assumed (possibly wrongly) that if you compared a picture that was 72 DPI and the same picture that was 300 DPI then the one at 300 DPI would be a much clearer and smoother picture when you zoomed in as 300 DPI would be more detailed. Is this correct or am i totally wrong?
 
mattjames said:
Thanks for that, it kind of makes sense but i seem to have read so much today that my brain has turned to mush. They said that they want images that are 1500 by 1000 at 300 DPI.

The thing that confuses me is this, I always assumed (possibly wrongly) that if you compared a picture that was 72 DPI and the same picture that was 300 DPI then the one at 300 DPI would be a much clearer and smoother picture when you zoomed in as 300 DPI would be more detailed. Is this correct or am i totally wrong?
Click to expand...

Printed out the 300 DPI would be much better than the 72 DPI when viewed from the same distance.

Forget about DPI when viewing on the screen, DPI only matters when you print.

Make 2 copies of a photo - one at 72 DPI and one at 300 DPI.
View them on the screen and they will look the same, because they are the same.

If however you enable reampling then the program will add or remove pixels and this will cause a difference, but this is due to the different number of pixels and has nothing to do with the resolution on screen.
 
Ok im kind of getting it. I was zooming into my pics and not seeing a difference which was confusing.

So for the purposes of printing 300 DPI is the best way. If i take the pictures that they want me to with my camera just on normal JPG format then copy these onto my PC and open them with Photoshop it says that the DPI is 72, what is then the best way of making this 300 DPI as they require?

Or would i be better shooting them in RAW as then i put these onto my PC they are at 240 DPI

Last question honest, then im going to go bury my head in the sand and get someone else to take the pictures.
 
mattjames said:
Ok im kind of getting it. I was zooming into my pics and not seeing a difference which was confusing.

So for the purposes of printing 300 DPI is the best way. If i take the pictures that they want me to with my camera just on normal JPG format then copy these onto my PC and open them with Photoshop it says that the DPI is 72, what is then the best way of making this 300 DPI as they require?

Or would i be better shooting them in RAW as then i put these onto my PC they are at 240 DPI

Last question honest, then im going to go bury my head in the sand and get someone else to take the pictures.
Click to expand...

Photoshop is using an arbitrary number of 72 DPI, it is just a number they put in because the box has to have some number in there. If I open my jpegs in different programs then I get different DPI figures in the box. Different programs use different numbers - think of it as their suggestion for when you print out. The raw program just uses a different figure - a different suggestion. It is only relevant when you print.

Now looking at your particular task, you need to supply an image which is 1500 pixels by 1000 pixels at 300 DPI (PPI). So the printed image will be 1500 pixels / 300 DPI (PPI) = 5 inches wide and 1000 pixels / 300 DPI (PPI) = 3.33 inches high.

Now your image may not have this width to height ratio, so that may need changing, and your image may not be 1500 pixels by 1000 pixels so that may need changing.

In photoshop you need to make sure that your image has a width to height ratio of 1500:1000 or 3:2, you may have to crop to get this.

You then need to change the size/resolution of the image and make sure that you select resample when you do this.
Change the DPI to 300 and change the pixels size to 1500 wide, the height should change to 1000.
Save at highest quality.

The reason you resample is that you need to create or get rid of pixels in order to change the pixel size and keep the resolution to 300 DPI.

If you do not resample then changing the DPI will just alter the size of the printout and will not change the number of pixels.
 
Ok the fog is starting to clear now. So just to clear up an issue in my head. If i was to shoot a picture on my camera using JPG setting and the same picture using RAW there would be no improvement in quality for printing purposes on the RAW file? I always assumed that there would be as the RAW file so so much bigger.
 
mattjames said:
Ok the fog is starting to clear now. So just to clear up an issue in my head. If i was to shoot a picture on my camera using JPG setting and the same picture using RAW there would be no improvement in quality for printing purposes on the RAW file? I always assumed that there would be as the RAW file so so much bigger.
Click to expand...

The raw file is bigger because the jpeg has been compressed. When you want to print the raw file you will have to change it to a jpeg and compress it anyway.

The raw does contain much more data than a jpeg which is why it is better to use raw if you are going to make changes on the computer with PP. With jpeg when you make changes on the computer the quality can suffer.

The raw also allows you to select what changes you wish to make after you have taken the shot. With jpeg changes such as sharpening, contrast, white balance etc are made in the camera and have to be chosen before you take the picture. With raw you can change these after and see the effects.

The changes can also be finer and selective. For example contrast changes in camera may be 2 or 3 steps, +1, +2 etc. on the computer the changes will often be from 0 to 100 so you can get much finer adjustment. It is also possible to change the contrast in one part of the picture only whereas in camera the whole picture is affected. Obviously the same applies to sharpening, saturation etc.

Most programs do not apply any camera settings when you import the raw file so the raw file straight from the camera will actually look worse than the jpeg!

Have a look here for more info. http://www.ronbigelow.com/articles/articles.htm it may be a bit too technical but the last bit of the 3rd article summarises it.
 
mattjames said:
They said that they want images that are 1500 by 1000 at 300 DPI.
Click to expand...

Suvv said:
Printed out the 300 DPI would be much better than the 72 DPI when viewed from the same distance.
Click to expand...
Sorry, but this is misleading.

All 1500 x 1000 images will look exactly the same if you print them the szme size, because the have the same number of pixels. End of.

If you print a 1500 x 1000 image at 300 PPI, it will be 5" by 3.3". It will look really good close up but if you put it on the wall and stand back it will be too small.

If you print a 1500 x 1000 image at 72 PPI, it will be 20.8" by 13.9". If you look at it close up it will look pixellated, but if you put it on the wall and stand back it will look really good.

One won't look better than the other, because at the end of the day they're both the same image with the same number of pixels.


So ... to comply with the magazine's requirements: (A) resize the image to 1500 x 1000 pixels; and then (B) chane the DPI setting to 300 DPI, making sure that you don't resize it at the same time. (Exactly how you do this depends on which software you use.)
 
StewartR said:
Sorry, but this is misleading.

I agree that it was misleading, some people would have said wrong:), to say that a 300DPI image would be better than a 72DPI image when viewed from the same distance. Your examples explain this well.


I am a bit confused with your comments however:

All 1500 x 1000 images will look exactly the same if you print them the szme size, because the have the same number of pixels. End of.

I agree that if they are all printed the same size then the PPI will be the same and they will look the same.


If you print a 1500 x 1000 image at 300 PPI, it will be 5" by 3.3". It will look really good close up but if you put it on the wall and stand back it will be too small.

If you print a 1500 x 1000 image at 72 PPI, it will be 20.8" by 13.9". If you look at it close up it will look pixellated, but if you put it on the wall and stand back it will look really good.

I agree with these 2 statements, this is where I was misleading / wrong.

One won't look better than the other, because at the end of the day they're both the same image with the same number of pixels.

This is where I am confused. Your previous 2 statements give distances, one where the 300 PPI is better and another where the 72 PPI is better.
Therefore the same image with the same number of pixels will look different at different PPI?
and a particular PPI will be better when viewed from a certain distance?
Click to expand...
 
mattjames said:
I have been asked to supply some pictures to a magazine. They want the pictures to be 300 DPI. Im using a Sony a200 camera, if I have the format set to FINE then when i look at the images on the memory card they are only 72 DPI. If i set the format to RAW they are 240 DPI. Does anyone know if i can get the Sony a200 to produce 300 DPI shots?
Click to expand...

your images will be up to 10Mp in size and i think big enough for the magazine

ask what size the magazine will need to reprint them at

from that you can size them in photoshop...i am not well aquainted with photoshop but i crop to full size in the parameters of my finished print at 300 dpi then crop
when you save it will be at 300 dpi to the size the mag wants
 
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