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EnLARGE app alternative for Android

hoganlia

Member
Joined
Jan 25, 2023
Messages
150
Location
Spain
Format
Medium Format
Hi folks, a Happy New Year to all and my fervent hope that the year ahead will be packed with exciting photographic adventures for all and sundry.

A few weeks ago I tried applying an enlarging formula so as to reproduce the outcome of a 5x7 print on to a 10x8 paper. I used a formula I found which scales up from measurement of negative size, height of the head and time to give the new time by ratios and inverse square law, apparently successful for most. I was not so lucky. Hunting around again I came across an app for iPhone called "enLARGE" which probably does exactly the same thing but I wondered if anyone knows if there is an Android app which does the same.

Any takers? Thanks in advance, Joe
 
Here is an algorithm I got from Gene Nocon‘s book.

T2=(L2/L1)^2 x T1

L1 = length of original print
L2 = length of new print
T1 = basic time of original print
T2 = time of new size print.

This works based on print size.
Gene presents it as part of the fstop printing he advocates, but it only deals with time so it should work even if you don’t use fstop printing. But any dodging or burning times may differ. But using fstop printing the new dodging and burning times would remain the same using the fstop system.

As you know, an issue for you is cropping or added white space since the ratios of your prints are different. But I would use the square of 7/10 in the formula to get exposure time.
 
lawnerd said:
Gene presents it as part of the fstop printing he advocates, but it only deals with time so it should work even if you don’t use fstop printing.
Click to expand...

@lawnerd ,
FWIW, f/stop printing actually does deal with time - increments of time that increase or decrease logarithmically, in fractions of stops, similar to how lens apertures increase or decrease.
Perhaps it should be called "fractional stop printing", but I expect that wouldn't be as catchy.
 
No fstop printing deals with increments of light. That is its virtue. Time and aperture both can be used to control light. It isn’t about time at all.
 
In my quote I was talking about the algorithm which provides a time. The algorithm only deals with time not fstops.
 
lawnerd said:
No fstop printing deals with increments of light. That is its virtue. Time and aperture both can be used to control light. It isn’t about time at all.
Click to expand...

Actually, it deals with increments of exposure, not increments of "light".
And of course exposure can be modified by modifying either time, or light intensity, or both.
Typically though f/stop printing practitioners pick a light intensity by choosing a magnification and a lens aperture and, in some cases a light strength setting on their light source, and then control the print density by modifying the time of exposure.
 

Please excuse my lack of reply... both mu wife and I have been down with a really bad case of flu since Christmas, better now but still not 100% and I have been lax getting back to things. I certainly do appreciate your comments and suggestions. Probably next week I'll be up to darkroom work and I plan to test things out.
 
Please excuse my lack of reply... both mu wife and I have been down with a really bad case of flu since Christmas, better now but still not 100% and I have been lax getting back to things. I certainly do appreciate your comments and suggestions. Probably next week I'll be up to darkroom work and I plan to test things out.
 
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