# How will an image from my Canon 7D look as an 8' by 8' poster? Will using TIFF over JPEG make a difference?

The organizer of a trade show just asked me if he could use one of the images that I took with my Canon 7D for as a backdrop. He said that he needs to photo in TIFF format, and said that he wants to blow it up to be a 8 foot by 8 foot poster.

I told him I'd send him the image, but just to satisfy my curiosity, is the image even going to look good at that size? I've never actually dealt with TIFF before (I only use RAW and JPEG), so does the format being in TIFF instead of JPEG make it easier to "blow up" to that size?

# Question 1: Does it look good at that size?

Your image will look good because most people will only look at it from afar. If it is at a trade show and depending on where exactly it is, no one may be able to get close to the image.

• Using Patrick Hurley's calculation of your image having 3456 pixels in both directions and thus at 8 foot a resolution of 36 PPI.
• Combining this with the data and formula provided in the above answer, we have
• Resolving power P = 0.00029
• We get the viewing distance D:

D = 1 / (P * PPI) = 1 / (0.00029 * 36 PPI) = 96 inches = 2.4 m

# Question 2: Does the format being TIFF instead of JPEG make it easier to "blow up" to that size?

Yes, TIFF can be lossless and JPEG never is. Additionally TIFF can also be 16bit, which won't help with printing but will help with interpolating to a higher resolution.

However, larger viewing distance would probably also give you good results from JPEG (see question1). Overall, TIFF is the preferred format by most printers and graphic designers. The only thing it is not good for is web, where size matters a lot and TIFF is just too large.

As Michael Clark pointed out, once you go to JPEG you loose information. TIFF only makes sense if you started in a lossless format like Canon's raw format .cr2.

• Please note: the main advantages for TIFF are only true if you convert the .cr2 file directly to TIFF. If you convert a jpeg to TIFF you lose a lot of the advantage. Jul 15 '13 at 18:43
• I added that information, I didn't include it first because I thought it obvious. Thanks for pointing it out! Bad oversight on my part. Jul 15 '13 at 19:16
• Excellent edit and information both here and in that link. Thanks Jul 15 '13 at 21:14
• Good to see my research is getting some use! :) Great answer. Jul 15 '13 at 21:29
• Thank you so much for all of your information! I really appreciate it :) Jul 15 '13 at 23:08

There are several things to consider. First 8x8 means the photo is being cropped to your short side which is 3456 pixels. This gives us 36 PPI, which is way low if we are viewing close up, but if the distance is 20 foot away, there is not an issue. As you get closer, the resolution will be an issue, so the real question is now our expected viewing distance.

The TIFF/JPEG format is not a significant issue, they are just two different image formats (although TIFF is lossless and going to be much larger).

• From 8 foot away the resolution is going to be fine. Jul 15 '13 at 19:16
• I agree, but it will depend on how critical it is being reviewed, the method of printing, and to some extent the image content. Jul 15 '13 at 19:47
• Yes, of course. jrista's answer ( photo.stackexchange.com/questions/1715/… ) is good read and goes into it in detail. 8 foot is for normal sighted people all they can theoretically decipher. So, best add in a bit of safety. Jul 15 '13 at 19:49