large prints, viewing distance, and screen preview

[Los]

I have a question about using my second monitor as a print preview screen for large prints. I work on a laptop, with a second larger monitor that i've calibrated and get matched prints from. i'm thinking of making prints 20x30 and larger, and i wanted to preview the quality (sharpness, aliasing, noise level) of the prints on the second monitor before sending them off to be made. here is my idea posed as a question:

it is my understanding that at normal viewing distances, larger prints can be made at ppi's lower than 300. if i stand at the intended viewing distance away from my second monitor, with the image magnified at 100%, would this be the same as viewing a portion of the final print at 100 ppi (or whatever my monitor resolution is)? and to take it further, would viewing the same image at 50% on the monitor be like viewing the print at 200 ppi at a normal or intended viewing distance?

does this make any sense?

[Kirk Gittings]

No, a screen is not a print. Print out a small section at home-say an 8x10 crop of the 20x30 and view that.

ALTHOUGH, I am not a believer in the "normal viewing distance" theory. When I go to shows people (me included) are pressing their noses against the glass to look at fine detail. IMO the NVD people are looking for minimum quality.

[Bruce Watson]

...if i stand at the intended viewing distance away from my second monitor, with the image magnified at 100%, would this be the same as viewing a portion of the final print at 100 ppi (or whatever my monitor resolution is)?

No.

Two main reasons. First, a monitor is a light source. A print is a reflective source. Second, a monitor has considerably less resolution than a print (unless you're using an iPhone, which has the resolution but not the size).

I'm not even going to get into things like paper texture, glazing in framing, how the ink colors and the phosphor colors differ, etc.

The bottom line is just no -- viewing on the monitor will not be "the same as viewing a portion of the final print at 100 ppi." It can be close. It can not be the same.

This is why we have proof prints. ;-)

[Los]

thanks, Kirk. The prints would not be for fine art purposes, so the NVD is a good starting point for me. the prints would be over a piece of furniture or high up on a wall out of a nose's reach

i'm exploring what degree of enlargement my 12mp dx sensor can tolerate and still make a "good" looking print. also, my research prior to this post suggests that i can maintain quality in the enlargement by reducing the ppi first, then only interpolating up as little as necessary. recently, i had interpolated up to 300ppi for three 20x30's from the same sensor and i felt they looked a little "rough" from all the over sampling.

i don't have a printer at home, so i thought there might be a way i could use the second monitor to help preview (or previsualize) what the prints would look like, since the color and contrast of that monitor are pretty consistent with the prints i get back.

carlos

[Los]

also Bruce, i found out that my monitor is about 90 ppi. i know that's low for most purposes other than billboards. i sharpen 16x20's at 50% magnification in PS, and adjust gamma and contrast at 25% magnification, fyi. i've been happy with the results from that work flow, but as i said earlier, the 20x30's looked roughed up by processing.

for what it's worth, i've begun shooting unit stills on movie sets. i know of at least one instance where another unit still photographer's work was cropped and used for the release poster. i suspect he was using a 12mp or 24mp fx sensor. either way, the cropping would have made the picture element very small for a 40" high onesheet.

http://www.keithbernstein.co.uk/gall...llery=invictus

keith wrote me that all three elements of the poster were taken from his unit stills. i wouldn't suspect that they were shot on medium format digital systems. those don't fit in blimps

[Bruce Watson]

...I found out that my monitor is about 90 ppi. I know that's low for most purposes other than billboards.

Billboards can be in the range of 3 ppi. I seem to remember that those huge multi-story high billboards in Times Square in NYC are printed in that range. It works because it's impossible to get up close to them, and from the sidewalk on the other side of the street they look gorgeous and sharp.

[John Rodriguez]

i'm exploring what degree of enlargement my 12mp dx sensor can tolerate and still make a "good" looking print.

carlos

It really depends on your opinion of a good looking print. I shoot landscape with a lot of detail and the largest I ever felt comfortable blowing up a print from my D200 (10 mp) was 12x18. Same with my 5D (12 mp). Any larger then that is too soft for my preference (which is how I wound up shooting 4x5), but YMMV. An image without micro detail can be printed larger.

[jonreid]

my printer has always instructed me to judge and set sharpness with the image at 50% in Photoshop, not 100%.

[Lenny Eiger]

i don't have a printer at home, so i thought there might be a way i could use the second monitor to help preview (or previsualize) what the prints would look like, since the color and contrast of that monitor are pretty consistent with the prints i get back.
carlos

I'm with Kirk on this one. Further, if you don't have a printer at home, then go buy one. If you are actually working and getting paid, there is no reason not to. They are just not that expensive. There are a hundred things you can learn about your images, about shooting, about color, lots of different qualities, etc, from actually looking at what the print will look like.

Lenny

[sanking]

I agree with Kirk about normal viewing distance. When prints are displayed in galleries as fine art most people look at prints, at least those prints that interest them, at very close distance, from 12"-18" to as close as 3"4". I assume, like Kirk, that they are interested in fine detail in the print.

And while you need to calibrate your monitor so that what you get in a print closely approximates the density and tonal values you see on the monitor, no monitor can give you an exact idea of what the print will look like. To know what a print will look like, you must make a print.

Sandy King