Maximum C41 commercial print size from the Epson V700

[Alan Johnson]

Previously I found the Epson V700 to resolve about 45 lppm on the negative:
http://www.dpug.org/forums/showthread.php?t=1914&highlight=
Commercial c41 printers I believe print at around 300 dpi *
Therefore the enlargement factor is 300/45 = 6.67
ie, from 35 mm, 6.7x 10 ins; from 2 1/4 x 2 1/4 , 15 x 15 ins; from 2 1/4 x 3 1/4 , 15 x 21.7 ins.
At these print sizes all the data recorded by the scanner is recorded on the C41 print.

*I have taken the figure of 300 as being sometimes quoted. Lab I use gave me a figure of 254 which appears to be a metric standard.
These estimates are of course approximate but if there are any errors in my calculation I would be glad for them to be pointed out, thanks.

 

[Doyle Thomas]

I guess I don't know what lppm is. you are dpi/lppm. on the other hand I try not to be so (if you will pardon the expression) **** about absolute scans other than for legal or science.

what is lppm?

 

[Alan Johnson]

2nd attempt:
lppm is line pairs per millimeter so there are 45 line pairs on each mm of film .
The C41 printer can do 300 lines on each inch of print, so each inch of print is equivalent to 300/45 =6.67 mm of film
For a 36 mm length of film this corresponds to 36/6.67 =5.3 inches of print.
So the first attempt above was wrong,I'm not too sure about the 2nd either.

 

[Alan Johnson]

2nd attempt:
lppm is line pairs per millimeter so there are 45 line pairs on each mm of film .
The C41 printer can do 300 lines on each inch of print, so each inch of print is equivalent to 300/45 =6.67 mm of film
For a 36 mm length of film this corresponds to 36/6.67 =5.3 inches of print.
So the first attempt above was wrong,I'm not too sure about the 2nd either.

 

[Alan Johnson]

3rd attempt
It seems a better way of doing the calculation is to take the Sandy King/ Scandig figure for the resolution of the V700, which was 2300 dpi and divide it by the resolution of the paper printer, 300 dp[.
For a negative 36mm wide, = 1.42 in, this is multiplied by 2300/300 to give a print width of 10.9 ins.

 

[John_M_King]

These as far as I can see are theoretical figures which I have found bear very little resemblance to actual results.

The largest size of print will also be dictated by the size of the negative that is being scanned. For what it is worth I have a A3+ print on the walls of my living room which came from a section of a 120 square negative. The print itself was a part of a negative which if I had used the full area available, the print would have been very close to 4.5 feet square.

 

[Alan Johnson]

Yes, it's a theoretical calculation. The object is to find the size of print at which the scanner output, which is by common consent about 2300 dpi, just reaches the maximum resolution of the C41 printer.

 

[artobest]

I don't believe there is common consent about the resolving power of the V700/750. Unless tests are done using a properly calibrated betterscanning.com holder (and they never are) then I take them with a grain of salt. The difference such a holder can make is too big to ignore.

 

[Alan Johnson]

About 2300 dpi is the best that can be obtained from the V700.
Please see post 6 in the link in the first post above.

 

[Alan Johnson]

About 2300 dpi is the best that can be obtained from the V700.
Please see post 6 in the link in the first post above.

 

[Alan Johnson]

Duplicate post.