I love NLP and this community. Just wanted to get that out there. I apologize in advance for the length of this post and any confusion caused by it. Thanks in advance.
My questions come from the perspective of someone who shoots a ton of medium format with the occasional 35mm. With 35mm my Canon 5D3 and macro lens (50mm f3.5 macro FD Mount via adaptor) can capture the entire frame and border without issue.
As far as medium format goes, I initially just reframed and shot the negative in a single frame. Then I got to thinking that I’d lose some of the image quality and ability to print large which are big reasons to shoot medium format to begin with. Not to mention the corners on this lens would cause the image to vignette. So I began shooting 4 RAW images per frame (6x6 and 6x7) then merging in LR. The problem is that the DNG files were 200+ MB and that’s too big for me. So I began to export the DNG as a JPEG with 100% quality and 600 DPI which yields files in the 12-17 MB range. Only then would I apply NLP so that I could have the option to convert again (in my early trials I converted the DNG then exported the positive JPEG but I like having the option to reconvert/edit within NLP).
My questions are:
-Is there a better workflow for medium format negatives?
-Is it better to stitch 4 frames then downsize rather than capturing the entire frame on a single RAW image? Is that just more work with no net benefit?
-Should I upgrade to a modern macro lens (EF Mount) or is my older lens not an issue?
-Is it better to convert the DNG file then export the completed JPEG or will an unconverted JPEG render similar results when NLP is applied?
Thanks again,
Omid
Interesting and somehow contradictory. Your workflow delivers lots of pixels with a rather limited potential for tonal finesse, hmmm.
What I do is similar, but I simply take one shot only. This is for cataloging and normal use. In case I want something really big, I can always rescan and stitch and live with that huge file, it’s not 100 in 100 but maybe just 1 in 100 - or not even that after all.
How big a difference of keeping four shots vs. one stitched DNG that contains those four shots? Unless you keep both original and stitched files, the difference might be bearable.
The magic lies in keeping track of the negatives. There’s at least one post dealing with this: Organizing Negatives For Scanning
Hi There!
• There is always a better worklflow, but this is mainly a financial topic: How much are you willing to pay for “better” glas, higher resolution cameras, more convenient film holders and stands, etc. … You are probably to one to answer this the best.
• My advice: Shoot it both ways, post it here, we are going to compare it together.
• I dont know the FD lens you are using, but you could get a Canon 100mm USM Macro and compare them both! Be sure to post your results here 
• Again try both ways out for yourself and post the results here.
Btw. I totally agree with Digitizer, especially regarding your digital archive.
Thanks, @Jaroslaw. I use the Canon EF100 Macro on EOS 5D Mark III and find that I get what I need for everyday use from those negatives - without stitching, hdr and averaged multishot exposures. I normally used 400 ISO film which has more grain than my camera has noise - unless of course my technique is inadequate.
To scan my 6x6 negatives I use the high resolution mode of my Panasonic G9 + 30mm macro lens : 80 Mpixels in 1 single photo 
I usually shoot E100 (ultra fine grain) and my 5D II plus 100mm Macro is all I need. My main final results are offset printed books (around A4) though.
Sharpness, stiching, ultra high resolution, etc is tempting. But what is often forgotten is that huge files take a lot of disc space and slower your computer when post processing them. Also they take longer to make and are only useful when you print at least 90x60cm or bigger.
When I need that kind of big prints (twice a year maybe) I send my film to a studio with an Flextight and have it manually scanned at 8000dpi for 15€.
Less hassle with gear means more time to shoot.
About (the Value of) Stitching
I shot most of my 645 negatives on 400 ASA film with the intention to print on A4/8x10in paper. This was an easy to live with configuration that provided plenty of detail and enough room for cropping and an occasional 20x30in size print. I am now bringing these negatives into the digital age.
I’ve recently tried stitching and found a few things that I’ll sum up below.
- The smallest detail on a negative is its grain.
- A 20x30in poster printed at 300 dpi requires 6000x9000 pixels equal 45 Mpixels.
- If I accept a 20x30in poster printed at 200 dpi, I need 4000x6000 pixels equal 24 Mpixels.
If we assume that - in normal use - we look at a poster for pleasure or memories and not for counting pixels, a 24 Mpixel camera will do just fine. This also means that stitching is only necessary if:
- Prints must be larger than 20x30 inches (50x75 cm)
- Your customer (or your own standards) ask for higher dpi prints
- Your printer/printing service can actually deliver higher dpi prints
- Bad lenses are used, lenses that don’t draw well at close distances
- Something else urges you to stitch
Print size being equal, grain will be the limiting factor, no matter if you print a file that has 24 or 2’400 Mpixels. The benefit of the larger file will be that the grain will (not really) look crisp and clean.
The bottom line: I’ll not stitch, except for the very few unusually good negatives that want a huge print.
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