Epson V750 120 film resolution

[bjolester]

I have an Epson V750 that I use for scanning my 120 films. Sometimes I scan at 6400 ppi and downsize the file, for marginal better resolution and less noise. But most often I scan medium format at 2400 ppi, resulting in a rather large tiff file. Does anybody know how many megapixels a scan of a well exposed Fuji Provia 100F 120 slide will correspond to if scanned at 2400 ppi on the Epson?

I am grateful for any advice on my query!

Best regards
Bjørn

 

[mfogiel]

The math is as follows: in case of a 6x6 shot, you have 2 1/4 x 2 1/4 (inches) x 2400 x 3 (channels).
To get the max optical resolution out of your scanner ( about 2200 ppi) you need to scan at full resolution, and you can reduce the size later. If you scan at 2400 ppi you will probably resolve around 1600 ppi.

 

[bjolester]

Thanks Marek!

I scan 6x7 film from my Pentax 67ii, and the size of the frames is actually roughly 70x56 mm. How would the maths be in centimeters?

 

[mfogiel]

1 inch = 2.54cm
For your guide, my Pentax 67 negatives scanned at 4000 ppi yield B&W files of 178MB, so for RGB that would be 534MB.

 

[bjolester]

Hopefully I have understood the maths behind this:
Pentax 67 frames : 2,76 inches x 2,20 inches x 2200 (max optical resolution) x 3 = 40mp

In others words it is possible to get results comparable to the best digital full frame bodies with an Epson V750 and 6x7 medium format colour film, if one has experience and good scanning technique?

 

[taemo]

The math is as follows: in case of a 6x6 shot, you have 2 1/4 x 2 1/4 (inches) x 2400 x 3 (channels).
To get the max optical resolution out of your scanner ( about 2200 ppi) you need to scan at full resolution, and you can reduce the size later. If you scan at 2400 ppi you will probably resolve around 1600 ppi.

by scanning at full resolution, do you mean scanning at 6400dpi then resizing it in post afterwards?

 

[Joosep]

In others words it is possible to get results comparable to the best digital full frame bodies with an Epson V750 and 6x7 medium format colour film, if one has experience and good scanning technique?

You can compare anything. Cats & dogs. Apples & oranges.

 

[Merlijn53]

Hopefully I have understood the maths behind this:
Pentax 67 frames : 2,76 inches x 2,20 inches x 2200 (max optical resolution) x 3 = 40mp

In others words it is possible to get results comparable to the best digital full frame bodies with an Epson V750 and 6x7 medium format colour film, if one has experience and good scanning technique?

Unfortunately, with an Epson v750 or any other flatbed, you never get anything that is comparable with the best digital full frame bodies. You can count as many pixels as you want, but scans from those scanners will never be really sharp. You need dedicated filmscanner to do that.
Frank

 

[mfogiel]

@taemo
Yes, tests have been made, and in order to get the best resolution. you need to scan at 6400 ppi, then you can comfortably resize to 2400 ppi, because you won't sacrifice anything, unless you want to print big. at which point it makes no sense to reduce first and uprez later. Keep it in mind, that without adjustable holder which you calibrate and without a method for keeping the film flat, the 2200 ppi resolution will not be reached.
@ Joosep
Even at 3800 ppi real resolution (Nikon CS 9000) your pixels will contain some noise because of film grains or dye clouds, so these 534 MB will not be as "clean" as digital pixels. Personally, for colour I would shoot either digital, or MF Portra and not worry about the resolution. For B&W digital makes me shrug the shoulders.

 

[bjolester]

You can compare anything. Cats & dogs. Apples & oranges.

I am not sure I get your point? My ambition with this tread was to learn more about scanning medium format film with an Epson V750 and how the result could be translated into megapixels.

I would not on any account start the discussion "scanned film on an Epson flatbed vs Nikon D810" 😱 That would be entirely fruitless...

 

[bjolester]

Unfortunately, with an Epson v750 or any other flatbed, you never get anything that is comparable with the best digital full frame bodies. You can count as many pixels as you want, but scans from those scanners will never be really sharp. You need dedicated filmscanner to do that.
Frank

There are out-of-production flatbed scanners that are superb, the Kodak Creo scanners comes to mind. I also believe that large format film scans very well on an Epson V750. The scans I get with medium format film on my Epson V750 are also very sharp, maybe not quite as sharp as my Sigma DP2 Merrill, which I use in conjunction with the Pentax 67ii, but at least as sharp as my 16mp Pentax K5 DSLR with high quality optics.

 

[Merlijn53]

There are out-of-production flatbed scanners that are superb, the Kodak Creo scanners comes to mind. I also believe that large format film scans very well on an Epson V750. The scans I get with medium format film on my Epson V750 are also very sharp, maybe not quite as sharp as my Sigma DP2 Merrill, which I use in conjunction with the Pentax 67ii, but at least as sharp as my 16mp Pentax K5 DSLR with high quality optics.

How do you compare the sharpness of a scan with the sharpness of a digital photo? Those are two completely different media. If you mean the details you can see in both, I don't know. Just put them next to each other.
I do know, that in a scan from a v750, a lot of details are missing, the grain for instance. But that is just pixel peeping. But if you are happy with it, there is no reason to compare. If you really need to know, put the v750 scan next to one from a Nikon, Minolta or Imacon. Then you will see what I mean.
For now it's just apples and oranges.

 

[taemo]

@taemo
Yes, tests have been made, and in order to get the best resolution. you need to scan at 6400 ppi, then you can comfortably resize to 2400 ppi, because you won't sacrifice anything, unless you want to print big. at which point it makes no sense to reduce first and uprez later. Keep it in mind, that without adjustable holder which you calibrate and without a method for keeping the film flat, the 2200 ppi resolution will not be reached.

I read in the past that scanning past 3200dpi was pointless as it would be introducing a lot of interpolation anyway.
Sometimes I would scan at 3200dpi and then resize the image by 10% in Photoshop but now a days I tend to just scan at 2400dpi.

Might give it another try

 

[Pioneer]

Ah, it has always been thus...my resolution is higher than yours, my lens resolves better than yours, my film resolves better than yours, my enlarger light source is better than yours, and on and on ad nauseum.

For scientists, cartographers, the military and a few others these things are important. Fortunately for many of us, photography remains a medium of vision, not one of numbers. Fine pictures can still be made using a flat bed scanner.

If some would like to discuss the merits of drum scanners perhaps they could start a thread on that topic. 🙂

 

[bjolester]

Pioneer: I agree a hundred percent with your wise words!

Marek: Thank you for supplying the maths for how to estimate megapixels from scanned images.

Here is an interesting article that deals with V750 and megapixels:

http://www.paulbohman.com/blog/2011/12/the-resolution-of-6x7mm-film-revisited/

 

[mfogiel]

@ taemo and bjolester

We have quite an expert on scanners and scanning here on the forum, perhaps you can look up his tests, although some stuff is only in Italian , his RFF user name is Fernando2.

 

[Fernando2]

Hi,

I reviewed and compared a few scanners (most of them are my own), including the V700.

This thread has a few links to my reviews
http://www.rangefinderforum.com/forums/showthread.php?t=137811&highlight=V700

Real-world direct comparison vs a drum scanner here
http://www.rangefinderforum.com/forums/showthread.php?t=143694&highlight=V700&page=4

More real-world comparisons here:
http://www.rangefinderforum.com/forums/showpost.php?p=2342884&postcount=6

V700 resolution charts here; including why you should scan at 6400 and then resample to whatever size you need, to get maximum quality from the V700 (as mfogiel correctly said):
http://www.rangefinderforum.com/forums/showpost.php?p=2272521&postcount=6

I worked 10+ years in the image analysis field; plus I LOVE film and scanners. That's why I love reviewing and pixel-peeping scanners! 😀

Fernando

 

[bjolester]

Thank you Fernando! I have read many of your comments about scanning and scanners on this forum with great interest. I have also studied your review of the V700, which I found very thorough and interesting.

The idea with this tread was to get some advice about scanning medium format film on the V750 and how the resulting digital file could be described in terms of megapixels. I have received advice which has shed some light on this matter, and I guess I need to find some literature to study, because I happen to find film scanning very enjoyable and interesting.

 

[Fernando2]

The idea with this tread was to get some advice about scanning medium format film on the V750 and how the resulting digital file could be described in terms of megapixels.

Well it's not so easy unfortunately.
With calibrated Betterscanning holders, the V7x0 can reach about 2300x3000 ppi +/- 5%.
From a 6x7 original this would give about "40mp equivalent".
But a 40mp digital camera would fare better in reality, thanks to better microcontrast and "cleaner" output. Our vision system likes microcontrast and does not like noise.

That said, a high quality 6x7 original skillfully scanned on a V7x0 is still a treat, and an excellent source for a gorgeous print. 😉

To get the best quality out of a V7x0, I recommend Betterscanning holders, reversed wet mounting, Vuescan Pro and a ColorRaid IT8 V50 target. Not an expensive bundle, by the way.

Fernando

 

[bigeye]

Fernando:

I've been away from the forum for awhile and missed your excellent posts. Thanks for the work. I've used the V700 for 6 or 7 years and while I consider it just adequate for 35mm, it is pretty good for my 6x6 and 4x5. I do need to get the betterscanning holders...

A shot from July downtown (1952 Leica IIIf/CV15/E100G/V700/Lr5):

Terrible?

-Charlie