Print sizes from scanned images.

I've seen one or two comments regarding the size of prints possible with scanned negs/slides. I would suggest the following calculations (but feel free to shoot me down in flames !)

35mm original - the short edge is approx 1 inch (25mm) so at 3200 dpi you get 3200 dots. For a print it is usually accepted that 300 dpi is 'near photo' so 3200 / 300 = 10.6r (10.7) . Using the same logic the 35mm side has 4480 dots - 4480/300 = 15. So a 10 x 11 print is possible.

66 original - Both sides are approx 2.25 inches, This gives 2.25 x 3200 =7200 dots 7200/ 300 = 24 so a square print of 24 x 24 inches is possible (A3 is approx 12 x 16 !)

4x5 original - short side = 4 x 3200 =12800 12800/300 =42"
Long side = 5 x 3200 = 16000 16000/300 = 53"
That's a BIG print

As a matter of interest at 3200 dpi a 35mm frame is approx 14MP, a sq format MF frame is 52Mp (actualy about 51.8) and a 4 x 5 scan is approx 204Mp

So even a 3200 dpi scan of a 35mm frame beats almost all digital camera output. An 1800 dpi scan of a 35mm frame still gives 4.5MP, a 350D is 8MP but with a smaller frame - giving more noise when enlarged.

Hope (i) I'm right and (ii) It's of use - I JUST ADDED THIS IN THE EDIT (iii) No one uses this post to start a digital vs Analogue discussion, it's a fast route to the ignore list !

digiconvert said:

I've seen one or two comments regarding the size of prints possible with scanned negs/slides. I would suggest the following calculations (but feel free to shoot me down in flames !)

<snip>
4x5 original - short side = 4 x 3200 =12800 12800/300 =42"
Long side = 5 x 3200 = 16000 16000/300 = 53"
That's a BIG print
<snip>

Click to expand...

I have printed several 45"x36" off scanned 5"x4" negatives
on my second-hand wide-format inkjet printer. Yum!
When you put a print that size in a frame and hang it on the wall it really dominates a room!

digiconvert said:

I've seen one or two comments regarding the size of prints possible with scanned negs/slides. I would suggest the following calculations (but feel free to shoot me down in flames !)

35mm original - the short edge is approx 1 inch (25mm) so at 3200 dpi you get 3200 dots. For a print it is usually accepted that 300 dpi is 'near photo' so 3200 / 300 = 10.6r (10.7) . Using the same logic the 35mm side has 4480 dots - 4480/300 = 15. So a 10 x 11 print is possible.

66 original - Both sides are approx 2.25 inches, This gives 2.25 x 3200 =7200 dots 7200/ 300 = 24 so a square print of 24 x 24 inches is possible (A3 is approx 12 x 16 !)

4x5 original - short side = 4 x 3200 =12800 12800/300 =42"
Long side = 5 x 3200 = 16000 16000/300 = 53"
That's a BIG print

As a matter of interest at 3200 dpi a 35mm frame is approx 14MP, a sq format MF frame is 52Mp (actualy about 51.8) and a 4 x 5 scan is approx 204Mp

So even a 3200 dpi scan of a 35mm frame beats almost all digital camera output. An 1800 dpi scan of a 35mm frame still gives 4.5MP, a 350D is 8MP but with a smaller frame - giving more noise when enlarged.

Hope (i) I'm right and (ii) It's of use - I JUST ADDED THIS IN THE EDIT (iii) No one uses this post to start a digital vs Analogue discussion, it's a fast route to the ignore list !

Click to expand...

In my experience you just can't compare digitally captured pixels to scanned film pixels. I know what the math says about scanned 35mm beating 35mm digital capture, but my eyes tell me that it just isn't so across the board. Even with the smaller sensor size than 35mm film, the dx sized sensors have far less noise than the film capture has grain (not quite the same thing, but close). You may be right comparing the very small sensor in the smallest point and shoots.

Your print sizes seem about right for good quality. A lot depends on the quality of the lenses used. My Mamiya 7 slides scan with good detail up to a much higher resolution than my 4x5 slides. I think the Mamiya captures more detail than the 4x5.

I think there is much to be said for you premise. It has been my experience that it is better to start with a scan at least 1.5x larger than the end size. This allows you to thoughtfully downsize and 'suggest' detail that isn't really there.

I've done 5' enlargements on backlit material from 6x6 , 12'x6' from a 35 mm (kodachrome 25) also on backlit and 16' and larger 4x5 on canvas that all came out very nice. Viewing distance is a bit of an equalizer and the 35mm was a bit iffy even at that. You and I might think that we should be able to see into the print as if it were real at these sizes, but I don't think the viewing public has the same expectation. The troubles I've had with enlargements like these are that grain can become very large and ruin areas where that should appear smooth.

On the flip side. I have found that an 8mp dslr will produce a much better image than an 8mp scan. I believe this to be a generational thing as well as D to D is inherently smother than A to D. It is not all that uncommon to enlarge a DSLR capture to 200 spi and get very good results or to res it up and still get good results. Resolution is not always the limiting factor with captures. Local contrast or micro contrast can become a bigger issue than resolution as you go larger.

<Shameless plug> To see my work blown up to 5' and 4.5' go to the MacDonald’s on Woodward ave and 13mile rd in Royal oak mi and look above the condiment stands. Its a 50's car themed McD's and they're using some of my car shots for decor</end shameless plug>

We have printed 60 x 90 cm glossies from a 35mm negative scanned with a Nikon Coolscan LS 5000. One subcontractor delivered fantastic results, three others ended up in the trash can.

If you have access to the printer and can calibrate it so that it meets your requirements, you can push the envelope a lot.

Blowing up (or resampling) a digital image from a Canon 20D tends to turn flat and unsharp at anything larger than A4 or double letter size.

I'm currently thinking to get a Coolscan LS 9000 for my 6x9 slides because the Canon 9950F definitely does have a limit @ 2.400 dpi. The 60x90 cm prints are not bad, but they could be crisper, and because I'm a freak when it comes to perfection I don't see an alternative.

I was thinking to invest into the new Fuji S5 Pro because I could use all my Nikon lenses with it, but as great as the images are, they are too small for my purposes. IMHO digital cameras are good stuff for letter size prints, but that's about it.

My biz partner is shooting digital and has to spend hours with Photoshop, but I prefer perfect slides, a nice scan and a click to print

I recently did my first 13x19 print from a 35mm negative. I scanned on the KM SD IV at max res, ended up with about a 70 meg file (OUCH), then carefully spotted, cleaned up and sharpened a bit with Neat Image, and then printed.

I was very impressed with the result, my first large print from the new printer. My friend has it hanging on her office wall and it's received quite a few compliments.

It's hard to compare the two. With the lack of noise/grain you can blow digital files up to huge sizes and if it's done intelligently they never exactly look bad, they just don't look very satisfying up close. People use the phrase "suitable viewing distance" a lot.

I'd also like to suggest that despite the limits of your scanner being very high, at some point you get diminishing returns in scanning film. At some point you're just oversampling the grain - which you might want to do for technical reasons, but you're not necessarily really adding new information. My personal rule of thumb would be that 35mm has about 10 megapixels of useful information, so that would put 6x6 at 35 megapixels and 4x5 at "bunches and bunches" (I can't count that high!).

I've been working with larg format inkjet printers for about 9 years now. To be honest you can go as low as 150 ppi and not be able to tell the difference between that and 300 ppi. Some printers have an optimal ppi like 190 ppi or so. It takes some fidling to find the sweetspot. Anyway I have printed a 35mm velvia chrome as big as 40 inches wide. It looked great, although it was used for a trade show banner so the closest viewing distance was about 12 feet. I scanned it at 2400 ppi and uprezed it with bicubic smoother in PS. I have another 35mm chrome that I printed to 22 inches wide. It looks great. 300ppi is the resolution needed for good offset printing presses, that sort of resolution is overkill for inkjet prints that hang on the wall.

D.

There's a couple of debates with the initial assumptions made in the first post. First not every scanner gets you to 3200ppi. My Nikon will get to 4000 and a good drum scanner in the right hands will do more. Secondly 300dpi is not always necessary or even desirable in a print. It depends on viewing distance and of course larger prints are often viewed from further away. West Coast Imaging (www.westcoastimaging.com) believe that very large prints actually look betterer at 200dpi.

Putting these things together I believe you can get a larger quality print from any original than opined by the original poster. Certainly I consider that a quality ( showable/saleable) print of 36" sq can be made from a well made 6x6 transparency and a drum scan. I have prints here which totally convince me of that and which suffer nothing against the same images printed at 16" sq. Further if you accept 200dpi for larger prints/greater viewing distances then the effective barrier becomes not the size of print the original can support, but the ability to find a machine which can make wider prints than LightJets and Chromiras can handle.

This does not of course work to negate the process suggested by the OP. It does however indicate that instead of a single model you need one for each scanner and viewing distance combination.