Increasing size of pic for pro Printing?

[P_fuzz]

hi,

I am about to do a little exhibition and the print lab says it only needs the pic @ 200 dpi on final dimensions
However I want it bigger?

My question is how much would I be able to increase the size of said TIFF file without loosing much quality?

thanks guys,
f

[mistermonday]

What are the dimensions of the final print? What is the current size of your tiff (pixel dimensions)?
Regards,
Murray

[girlsfather]

I always would work on original file size at least, when working on the file.
If the largest output is going to be larger (in means of pixel-size) than the original, I would recommend to have the RAW developed in increased size.

It also depends on the output source.
My Epson 4800 inkjet is best at 360dpi, when printing directly out of photoshop.
As I was told, that has to do with the 1440/2880dpi resolution.
(At 300dpi, all diagonally lines where interrupted)
Maybe that is not happening with a RIP-Software.

So I would recommend to have a test printed. Maybe from two different services and or on different media.
So you really can be shure quality is at its best.

Qood luck with your exhibition!

Michael

[TommyO]

P_fuzz,
You have to clarify "bigger". The "dpi" (dots per inch) relates to print resolution; often confused or accidentally swapped with "ppi" (pixels per inch) which relates to screen resolution. "Bigger" would be interpreted by most of us as actual width x height, in inches. Do you mean width x height ?

If you mean you want to increase width & height, then you should try to keep the image resolution (ppi) close to what the printer will require, i.e. 200 ppi. This allows you to control the image resolution, rather than depending on the printer.

Photoshop's internal algorithms for changing image size work fine for doing all the conversions. Follow the norm of using "bicubic smoother" for enlargements, assuming your image is a normal color composite. You can increase a 200 ppi image roughly 2 or 2.5 times its original size an maintain clarity. After that, it depends on the colors, clarity, and level of detail in the original image.

Also keep in mind that large prints, i.e. 11 x 14 or larger always look a little grainy if viewed up close. The idea is to view larger prints from a farther distance. If the exhibition layout does not allow for people to stand far enough away, i.e. 5 ft or more, you may be better keeping to smaller prints.

Also, as girlsfather mentioned, it also depends on the print media (paper). I would always do a batch of test prints prior to the exhibition.

[P_fuzz]

thank you all for your replies,

I want to roughly increase to 38X60 cm (around 14x22 inches) and this is what I have now 6.7x10.1 inches on 300 pixels per inches (is that ppi?)

I am going to run some tests prior final prints are made, for now I need to set on size and try get some sort of print sponsorship!

PS: unfortunately the file attachment is not working

[RokcetScientist]

Originally Posted by P_fuzz

hi,

I am about to do a little exhibition and the print lab says it only needs the pic @ 200 dpi on final dimensions

You probably need even less dpi, because it's an exhibition, and people will be looking at the print from a couple of feet, or more, distance. So you won't need "photo quality" prints ( = 300dpi, observed at 1 foot distance).

However I want it bigger?

Bigger than what?

My question is how much would I be able to increase the size of said TIFF file without loosing much quality?

Depends on a) how large you want the print, and b) how much image quality loss is acceptable to you. I.o.w. that is completely subjective.

Here's a chart showing what max sizes you can print at "true photo quality" ( = 300dpi observed at 1 foot distance). For an exhibition you obviously need less dpi, so you can print bigger.

http://i75.photobucket.com/albums/i3...intChartQG.jpg