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06-01-2012, 05:33 AM   #31
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QuoteOriginally posted by stevebrot Quote
Not at all. I can create a huge file full of junk, similar the CCD scans I used to get from Costco.
As for the resolution calculations...the proof is in the scan. None of the current Epson flatbeds deliver over 2400 dpi. That is easy enough to demonstrate by simply scanning at higher settings and comparing to a 2400 scan. If you like, I can try and find the results from my V700 test scans. That failing, a comparison between the V700 and the Coolscan 5000 ED (previously posted here on PF) may provide some perspective.
P.S. The top of the falls in the detail views is where three unfortunate hikers were swept to their deaths last week during similar high water conditions. Very sad.
Steve, thanks for this. I just started using an Epson V500 and I was wondering whether there was any point in scanning above 3200ppi and it looks like the answer is no - which is a bit reassuring because it would be sad is such a cheap scanner could achieve better results than a dedicated Nikon film scanner. One day if I find one of the slides I took years ago of a USAF resolution target, it would be interesting to compare the detail at the various scanner resolutions. Of course if I could still get some Fujichrome 100F processed, it would be an even better test.

09-13-2013, 10:18 PM   #32
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Let me join this thread with some question.
I'm new with the concept of film scanning. I understand what dpi/ppi is, I understand all the numbers related with the subject. Still, I am unsure.
I got used to the fact my K-5 gives me a 16 Mpx RAW file. I open it and develop with Lightroom. The 16 Mpx file is great since I can do substantial cropping when needed without losing the image quality. When it comes to producing the output, I know what resolution to choose for printing or for screen.

Besides, I understand that 16 Mpx is not the actual resolution because it is the lens that controls the real resolution. Let us talk on maximum possible resolution instead.

Now, I need to scan a 135 film. My Canoscan 9000F allows me scanning film up to 9600 dpi and outputting TIFFs. I'd like to import the TIFF to Lightroom and make creative fixes as it were a DNG from the DSLR. Now: What scan resolution is appropriate to achieve the results not worse from what I get from the K-5 as DNG?Is it possible at all?
09-14-2013, 09:18 AM - 1 Like   #33
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QuoteOriginally posted by StefanMikes Quote
...
Now, I need to scan a 135 film. My Canoscan 9000F allows me scanning film up to 9600 dpi and outputting TIFFs. I'd like to import the TIFF to Lightroom and make creative fixes as it were a DNG from the DSLR. Now: What scan resolution is appropriate to achieve the results not worse from what I get from the K-5 as DNG?Is it possible at all?
Read a review about your scanner here at Filmscanner Info

According to their tests, anything above 1700 ppi (a 4 megapixel file) is just scaling up the image and does not capture anymore resolution. You have to pay-to-play with film scanners. The smaller the negative, the greater the MTF of the optical path of the scanner needs to be and that costs *lots* of money.

Scanning software such as VueScan has the option of a DNG output file. It is a TIFF-DNG ( a partial implementation of the DNG spec) which LR will read. It also helps to scan 16 bit BW or 48 bit color and use a wide color space such as the ProPhoto RGB (supported by VueScan's output). When you convert a RAW file in LR from your digital camera you are working in the ProPhoto RGB color space, btw.

In short, I don't think you will ever come near your digital camera with that scanner except for web display images. In general, if you want to get quality of your digital camera you need a better scanner and shoot medium format film ( easier for scanners to get better results), IMHO.
09-14-2013, 04:05 PM   #34
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This is very interesting information! You put enough facts in your answer tuco and I am really grateful.

09-14-2013, 05:50 PM - 1 Like   #35
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That is right in my experience.
I have a V600. If I get a good C41 6 x7 negative, it gives a nice sharp file of say 1800 to 3000 pix wide for my 22 inch Eizo. Quite OK for my use.
However the scanner can not produce sharp enough images from a 35mm negative, not matter what "dpi" is selected.
I pulled it apart and did some tests to see basically how it works optically.
Image you had a perfect scanner that could record faithfully an 1800 pixel wide image on its single row sensor while it moved across the negative.
To do that you would need 1800 perfectly parallel beams of light from the top led bar, and the sensor would not "see" the adjacent beams, and it would take a fresh "snapshot" in time at each pixel of displacement.
Of course, the real consumer grade flat bed scanners do not have that optical capability to work like that. It appears that each pixel on the single row sensor receives an overlapping cone ( actually I saw an oval cone) of confusion, and i suppose they use dsp to derive the image profile in 2D and then map it to the selected resolution. So the bigger the neg, the better image they give
09-14-2013, 08:26 PM   #36
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QuoteOriginally posted by wombat2go Quote
That is right in my experience.
I have a V600. If I get a good C41 6 x7 negative, it gives a nice sharp file of say 1800 to 3000 pix wide for my 22 inch Eizo. Quite OK for my use.
However the scanner can not produce sharp enough images from a 35mm negative, not matter what "dpi" is selected.
I pulled it apart and did some tests to see basically how it works optically.
Image you had a perfect scanner that could record faithfully an 1800 pixel wide image on its single row sensor while it moved across the negative.
To do that you would need 1800 perfectly parallel beams of light from the top led bar, and the sensor would not "see" the adjacent beams, and it would take a fresh "snapshot" in time at each pixel of displacement.
Of course, the real consumer grade flat bed scanners do not have that optical capability to work like that. It appears that each pixel on the single row sensor receives an overlapping cone ( actually I saw an oval cone) of confusion, and i suppose they use dsp to derive the image profile in 2D and then map it to the selected resolution. So the bigger the neg, the better image they give
Do you believe it is better to order prints from the lab and scan the prints?
09-15-2013, 05:48 AM - 1 Like   #37
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QuoteOriginally posted by StefanMikes Quote
Do you believe it is better to order prints from the lab and scan the prints?
Since most - if not all, mini labs scan and print rather than make optical prints, it may be better to just get the scans to begin with.

09-15-2013, 06:26 AM   #38
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QuoteOriginally posted by StefanMikes Quote
Do you believe it is better to order prints from the lab and scan the prints?
Stefan, I have not tried that.
However I have made wet b/w prints here in my darkroom and scanned on the V600.
"Ilford Multigrade 1V RC deluxe 8 x 10 pearl" in Ilford MultiGrade paper developer.
The enlarger lens is a Rogonar -S 1:2.8 50mm *
Both the prints and the scans on the Eizo are, to my standards, very good.
Of course the scans have the artifacts of the paper, but for portraits etc, that is not so bad.

In this application, the optical resolution of the V600 is being fully used, and I think its fidelity is excellent.
Prints mostly of my family which i don't put up, but I recall I might have put a scan up on PF a while ago.

* I am using this lens on dslr sensor and i know it is sharp across the plane on the 3 clicks f/ 8 ~ 11
09-15-2013, 06:54 AM   #39
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QuoteOriginally posted by wombat2go Quote
Stefan, I have not tried that.
However I have made wet b/w prints here in my darkroom and scanned on the V600.
"Ilford Multigrade 1V RC deluxe 8 x 10 pearl" in Ilford MultiGrade paper developer.
The enlarger lens is a Rogonar -S 1:2.8 50mm *
Both the prints and the scans on the Eizo are, to my standards, very good.
Of course the scans have the artifacts of the paper, but for portraits etc, that is not so bad.

In this application, the optical resolution of the V600 is being fully used, and I think its fidelity is excellent.
Prints mostly of my family which i don't put up, but I recall I might have put a scan up on PF a while ago.

* I am using this lens on dslr sensor and i know it is sharp across the plane on the 3 clicks f/ 8 ~ 11
Thank you again wombat2go.
It looks I put too much hope in the inexpensive scanner. As I can see it now, there is no other way than a darkroom.

---
P.S. I didn't see the post of LesDMess before. Thank you, too.

Last edited by StefanMikes; 09-15-2013 at 07:12 AM.
09-15-2013, 07:03 AM - 1 Like   #40
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Well, one possibility is for you to stretch to 6 x 7.
I found it is fun and rewarding, the used equipment is low cost now.

The excuse would be you had to do it to save cost of pro scanner!

Some of the Large Format users are using print paper as camera negatives, then scanning on a low cost flatbed and inverting in post process . Some results are very good.
09-21-2013, 08:23 AM - 1 Like   #41
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QuoteOriginally posted by StefanMikes Quote
Let me join this thread with some question.
I'm new with the concept of film scanning. I understand what dpi/ppi is, I understand all the numbers related with the subject. Still, I am unsure.
I got used to the fact my K-5 gives me a 16 Mpx RAW file. I open it and develop with Lightroom. The 16 Mpx file is great since I can do substantial cropping when needed without losing the image quality. When it comes to producing the output, I know what resolution to choose for printing or for screen.

Besides, I understand that 16 Mpx is not the actual resolution because it is the lens that controls the real resolution. Let us talk on maximum possible resolution instead.

Now, I need to scan a 135 film. My Canoscan 9000F allows me scanning film up to 9600 dpi and outputting TIFFs. I'd like to import the TIFF to Lightroom and make creative fixes as it were a DNG from the DSLR. Now: What scan resolution is appropriate to achieve the results not worse from what I get from the K-5 as DNG?Is it possible at all?
There are many parts that determine your ability to achieve the finest detail and it may not be the lens. For instance I have the 14.6MP K20D and tested my 50mm Pentax lenses and got the results shown below.

Link to full res -> http://www.fototime.com/AFA3C6EDB6A663D/orig.jpg


Then I tested them with a roll of Kodak Techpan, shot at ISO25, developed in Technidol and the scans from my Coolscan shows a considerable improvement in actual resolution achieved over my K20D. The right most picture is a shot of the actual frame of film using the Macro on my Pentax Auto Bellows and as you can see, there is still even more detail to achieve - more than double that of the K20D. And keep in mind that in the case of digital sensors, doubling the number of pixels is not actually double the resolution achieved.

Link to full res -> http://www.fototime.com/A08A371F28ED137/orig.jpg

In this case it is plain to that the lens is by no means the bottleneck in resolving actual detail.
09-21-2013, 11:26 AM   #42
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QuoteOriginally posted by LesDMess Quote
There are many parts that determine your ability to achieve the finest detail and it may not be the lens. For instance I have the 14.6MP K20D and tested my 50mm Pentax lenses and got the results shown below.

Link to full res -> http://www.fototime.com/AFA3C6EDB6A663D/orig.jpg


Then I tested them with a roll of Kodak Techpan, shot at ISO25, developed in Technidol and the scans from my Coolscan shows a considerable improvement in actual resolution achieved over my K20D. The right most picture is a shot of the actual frame of film using the Macro on my Pentax Auto Bellows and as you can see, there is still even more detail to achieve - more than double that of the K20D. And keep in mind that in the case of digital sensors, doubling the number of pixels is not actually double the resolution achieved.

Link to full res -> http://www.fototime.com/A08A371F28ED137/orig.jpg

In this case it is plain to that the lens is by no means the bottleneck in resolving actual detail.
Thank you very much Les.
What I found out myself so far is that a budget flatbed scanner with film scanning capability is not the answer. And I cannot afford a high quality film scanner.
It looks film scans from a good lab will have to do regarding color film and I decidedly want to re-create my wet darkroom for B&W films ;-)
09-21-2013, 11:43 AM - 1 Like   #43
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A more realistic test LesDMess should do is for situations you will be more likely to encounter is shooting a digital at the K5 level at ISO 400 and compare to ISO 400 35mm film. TechPan has been discontinued so you will be hard pressed to get your hands on that and shooting at ISO 25 is mostly handhold bright conditions and/or tripod.
09-21-2013, 12:21 PM - 1 Like   #44
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QuoteOriginally posted by tuco Quote
A more realistic test LesDMess should do is for situations you will be more likely to encounter is shooting a digital at the K5 level at ISO 400 and compare to ISO 400 35mm film. TechPan has been discontinued so you will be hard pressed to get your hands on that and shooting at ISO 25 is mostly handhold bright conditions and/or tripod.
As a test engineer for over 2 decades, I actually put some thought when I did this test and that it is for the purpose of determining just how much can be resolved on Kodak Techpan shot at ISO25 and developed in Technidol using the setup I had to work with in a manner that is repeatable . . .

To your point the only realistic test you can conduct is one you conduct yourself. From that perspective here is one such realistic test that I did using 35mm Fuji Sensia 400 compared to a 24MP Sony A900 at ISO400. Note that this is simply a crop from each - a 1 for 1 pixel comparison.


Link to full res -> http://www.fototime.com/B6BF7BF83DA25A7/orig.jpg


The A900 didn't become available until years after I shot that slide though . . .
09-21-2013, 12:27 PM   #45
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QuoteOriginally posted by LesDMess Quote
...
To your point the only realistic test you can conduct is one you conduct yourself. From that perspective here is one such realistic test that I did using 35mm Fuji Sensia 400 compared to a 24MP Sony A900 at ISO400. Note that this is simply a crop from each - a 1 for 1 pixel comparison.

I don't do a lot of testing. I'd rather just go out and shoot. And when I shoot film it is mostly medium format. I scan on a 9000ED and I do see how it compares to my 36MP digital camera.
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