holmburgers
Member
Hi y'all,
So I've posted a thorough explanation of what my proposed method is on the "autochrome recipe" thread and another older thread "restarting my autochrome experiments....". But I felt bad about hijacking these more historical discussions and thought I should just create a new thread to share my experiment/plan.
The goal is to recreate the look of autochrome & dufaycolor photographs. Instead of attempting to reproduce these methods exactly, which were developed 103 years ago, I figured there had to be some modern methods that would be much easier.
I came up with the idea of using slide film to record the reseau, RGB-colored screen, by photographing a white TV screen (RGB elements of equal amplitude) TV screen.
Then, thru pin registration, this screen will be attached to ordinary panchromatic b&w film, exposed, separated, reversal processed and re-registered.
Voila!
Naturally, the irony is how retrogressive this technique is... using color film to make a reseau only to permit making another color picture on b&w film. .....doesn't bother me a bit though....
So, after going thru all the theoretical steps, I've moved to the practical steps, namely, calculating magnifications. However, I've come up against some problems.
To make a .05mm TV pixel (approx.) equal to a .005mm autochrome starch we need a magnification of 1/10th. Take a 12"x16" TV screen and 4x5" film and my calculations say that the TV can't fill the whole frame at that magnification. SOO either we have to sacrifice resolution or find a higher-definition screen.
I haven't done the math yet, but perhaps a 1080 hi-def screen would do the trick. As I don't have one ($), a computer monitor is probably the next best thing.
However, this got me thinking about lens/film resolution. I haven't done a ton of looking into it yet, but it seems like 60 lp/mm is about the limit of resolution.(??) That equals .017mm per line pair.
Would it be fair to say that it's impossible to reach the resolution of the autochrome starch grains with a typical lens/film combination? I thought that making a reseau thru optical means would be significantly easier, and indeed it is, but at a cost I guess.
I would appreciate any input on my calculations & in determining the maximum resolution available by the method I've outlined. Either way, I'm still going to attempt this.
Thanks!
So I've posted a thorough explanation of what my proposed method is on the "autochrome recipe" thread and another older thread "restarting my autochrome experiments....". But I felt bad about hijacking these more historical discussions and thought I should just create a new thread to share my experiment/plan.
The goal is to recreate the look of autochrome & dufaycolor photographs. Instead of attempting to reproduce these methods exactly, which were developed 103 years ago, I figured there had to be some modern methods that would be much easier.
I came up with the idea of using slide film to record the reseau, RGB-colored screen, by photographing a white TV screen (RGB elements of equal amplitude) TV screen.
Then, thru pin registration, this screen will be attached to ordinary panchromatic b&w film, exposed, separated, reversal processed and re-registered.
Voila!
Naturally, the irony is how retrogressive this technique is... using color film to make a reseau only to permit making another color picture on b&w film. .....doesn't bother me a bit though....

So, after going thru all the theoretical steps, I've moved to the practical steps, namely, calculating magnifications. However, I've come up against some problems.
To make a .05mm TV pixel (approx.) equal to a .005mm autochrome starch we need a magnification of 1/10th. Take a 12"x16" TV screen and 4x5" film and my calculations say that the TV can't fill the whole frame at that magnification. SOO either we have to sacrifice resolution or find a higher-definition screen.
I haven't done the math yet, but perhaps a 1080 hi-def screen would do the trick. As I don't have one ($), a computer monitor is probably the next best thing.
However, this got me thinking about lens/film resolution. I haven't done a ton of looking into it yet, but it seems like 60 lp/mm is about the limit of resolution.(??) That equals .017mm per line pair.
Would it be fair to say that it's impossible to reach the resolution of the autochrome starch grains with a typical lens/film combination? I thought that making a reseau thru optical means would be significantly easier, and indeed it is, but at a cost I guess.
I would appreciate any input on my calculations & in determining the maximum resolution available by the method I've outlined. Either way, I'm still going to attempt this.
Thanks!