question about using the 4x5 Epson scanner lens to scan 5.9" wide and stitch 8x10

[Jim Andrada]

For two-up 4 x 10. why not just cut the 8 x 10 in two?

[Pere Casals]

This bell seems extraordinarily sharp for a 6m print! I guess my question is: at what viewing distance does this represent?

To me a 6m print from that 8x10" negative scanned with the Epson is perfect at 2m distance, so a 3m print would be perfect at 1m, and a 1.5m print would be good at reading distance.

This would be for a demanding photographer, IMHO a regular viewer would not complain if distance was shorter.

Unlike most folks (it seems--I agree it is highly unusual to request a drum scan of an 8x10 at >2000--I've spent the last two years trying to do this), I am very interested in how close I can walk up to a mural sized print and it look sharp. I can get the sharp viewing distance down to about 6" with an 8x10 drum scan at 3200--but only for a print that's 60" wide; for 120" wide I'm stuck with a 13" viewing distance at best. [don't worry, I know this is crazy]

I've been also digging in that...

IMHO it's about digital post processing, this is very important.

But there is another answer: Sally Mann. She had been departeing from silver nitrate, br salt, glass sheets, pottery... to end in the most impressive big prints many have ever seen on a wall. Plenty of autenticity also.


We have to return back to the darkroom... this is the key. Making sound negatives that print amazingly well, and then projecting the negative on silver paper.

I made tests I found that even an old enlarging lens introduces no loss in the image quality, I found that my old, cheap and scratched "no letter" Rodagon takes insane 145 lp/mm from the negative and it crafts every bit on the paper:





Back to the darkroom !!!


It's cheaper, it's not reprography, it's authentic.

But one also has to obtain better tonal results than with hybrid. This looks a challenge, but's about technical preparation.

[Michael Roberts]

Pro scanners make a very good digital image optimization, the Epsons are not Pro and you have to do it later, but with a few clicks an LF scan from an Epson is amazingly close to the Howtek:
There is no secret, it's about downloading the crops from that "side by side" and sharpening to optimum, and adjusting curves to match.

I really, really want to believe this--it would make my life so much easier! But I also understand the seductive power of wishful thinking and confirmation bias, so I really, really want to do this kind of comparison test myself--hence this inquiry into what/how to wring the most resolution out of an Epson....

[Michael Roberts]

To me a 6m print from that 8x10" negative scanned with the Epson is perfect at 2m distance, so a 3m print would be perfect at 1m, and a 1.5m print would be good at reading distance.

This would be for a demanding photographer, IMHO a regular viewer would not complain if distance was shorter.

Agreed!!!

[Michael Roberts]

Back to the darkroom !!!

I really, really do not want to believe this!

Oh, Reality--such a difficult mistress.

[Michael Roberts]

For two-up 4 x 10. why not just cut the 8 x 10 in two?

Yes, Jim, I agree--cutting the film after it's processed would not be a problem (same w/ two-up 5x8s). But...is there a 4x10 holder available? If not, how would this help? Sorry to be slow....

[Pere Casals]

Oh, Reality--such a difficult mistress.

The lightjet/lambda/inkjet way is also demanding.

We need 12 to 20 sharp pixels per mm.

> We have to work 16bits per channel with an oversampled image (what is oversampled from a 8x10 scan? )

> We have to perform initial sharpening

> Edition

> After edition sharpening

> Image reduction (bicubic for reductions) to the printer matrix size

> A Pixel level sharpening

> A viewing distance intended additional sharpening

> The right raster, the right ink set, piezography, etc.

[Michael Roberts]

True dat!

[interneg]

I really, really want to believe this--it would make my life so much easier! But I also understand the seductive power of wishful thinking and confirmation bias, so I really, really want to do this kind of comparison test myself--hence this inquiry into what/how to wring the most resolution out of an Epson....

Whether people like it or not, it's safest to regard the best possible output from an Epson to be 1200ppi at not spectacular MTF performance. No amount of silly claims of magical sharpening routines can pretend that the fundamental optical performance is poor, or that manipulating low resolution web images somehow 'proves' it isn't. The A3 Epsons give you a fighting chance at getting better performance thanks to an actual focusing system.

[Pere Casals]

Whether people like it or not, it's safest to regard the best possible output from an Epson to be 1200ppi at not spectacular MTF performance.

interneg, your statement is NOT ridiculous

But it also happens with the other scanners:

https://www.largeformatphotography.i...=1#post1509776
https://www.largeformatphotography.i...=1#post1479178


It is interesting to compare LF performance of the V700 vs your X1

Your hasselblad X1 is pure gold (+6000dpi effective) for 35mm, but this is a LF forum, IIRC, and in that context the V700 outresolves the X1.

in the hor axis:

> For 4x5" the V700 delivers 2900dpi effective, your X1 delivers 1800.

> For 5x7" the V700 delivers 2900dpi effective, your X1 delivers 1440 (the half).

> For 8x10" the V700 delivers 2300dpi effective, your X1 delivers 0.

(for the vert V:2300-2300-1700 vs X:1620-1300-0) (the x1 has a 10% resolving power loss in the Vert vs Hor, 20% loss in the Epson case)


If for 4x5" your X1 extinguishes contrast at 1800dpi... do you think that you will have "spectacular MTF" at 1200 dpi ? You have worse MTF than the Epson at 1200dpi !


Also you should consider that anyway the LF lenses-films extinguish contrast at similar (or lower) cycles/mm than the Epson, so a higher resolving power has a minor effect.

The A3 Epsons give you a fighting chance at getting better performance thanks to an actual focusing system.

With the V700 if you scan 8x10" on glass bed you have perfect focus, on any doubt you may even wet mount on bed.