Imaging direct by lens is best to give overall performance. Subsequent measures of film and of the printing process shows the weak points. Is it camera, film, process or printing?
PE
PE
I have such a target, and will try to implement Bill Burk's idea of repeated resolution patterns which follow the step pattern on my Stouffer wedge. Having such a special resolution target would allow me to see (and measure) density, grain and resolution versus exposure in one single test clip, which gives me much more reliable results than determining the three properties from three separate test strips.
Since we have reason to believe that higher contrast yields better resolution unless grain grows out of control, I think I will try to create this resolution strip with repeated patterns on Fuji Velvia 50. Not only is this film plenty sharp enough to make a resolution target for my purpose (Tri-X, HP-5+, Delta 3200), it also saves me the second copy step or the (very expensive) inverted target.
Still not sure why you want to contact print sources to the films, rather than image direct by lens?
Since none of the films I want to evaluate are sensitive to IR light, transparency or opaqueness to infrared light is irrelevant.My initial thought of using Velvia: It's a dye based result, and totally transparent to infrared. Thus E6 might be less suited to the purpose of making a sandwich with sensitometric strip... I could be wrong about this, because you really are looking at high resolution - high contrast signal and only looking to see if the signal exists.
I have no plans of using a camera for this purpose, and ideally not even a lens between target and film test clip. As Michael writes, contact printing is the way to go. It's time to put that engineering degree of mine to use ...Since you get good results already with a camera, maybe the test device you make could be a camera-based concept: Like maybe a half-frame SLR (e.g., Olympus Pen) with macro bellows and a suitable original target, where you expose at exact same f/stop for all... but vary the exposure time (or if using flash, flash intensity). Using a half-frame camera would give you more exposures per roll.
Rob, anyone with computer skills can create such a resolution test chart from scratch, getting it onto a real medium with the desired resolution is the trick that few companies can perform - for good money.
Ron: assuming you refer to figures 61-64, the printed pages suffer from the same issue as the scans you posted here: resolution of tested medium by far exceeds resolution of presentation medium. It would be very helpful if you could post a cropped version of these images in full resolution, e.g. the groups starting with 7.1.
I do not think that flare would be a problem using a lens.Here is a description by Kornelius Fleischer of how he did tests for Zeiss:
http://photo.net/leica-rangefinders-forum/009t9L?start=10
Ron: assuming you refer to figures 61-64, the printed pages suffer from the same issue as the scans you posted here: resolution of tested medium by far exceeds resolution of presentation medium. It would be very helpful if you could post a cropped version of these images in full resolution, e.g. the groups starting with 7.1.
Ron,
Looking at a JPEG file is meaningless. Because of the way JPEG compression divides the image into 'super pixels', I can start to see alaising in the 4.0 bars of the Ilford print.
For those that don't know, all a PDf file is, is a file containg "PostScript" language and data which for the purposes of this document contains vector data for position and dimensions of shapes. Acrobat is just a rendering engine for PostScript landguage/data.
Yes, but....
An Acrobat file can also include non-vector data bit mapped image files in a variety of formats (such as TIF and JPG). An Acrobat file is simply a 'wrapper' that can contain data in a variety of formats.
the PDF I posted a link to can be zoomed into (max 3600% in acrobat) and the detail is there. What you can print that to is another matter.
As has already been determined, unless you have a device capable of outputting that at the size you want, you are stuffed.
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