Sharp on the light table but blurry on the scan?

[Certain Exposures]

I have two frames of two different road signs. Both look tack sharp under a 5x loupe on the light table. The text in one image is tack sharp in the scan at 33%. The other image's text shows noticeable blur/'doubling' at 33%. I'm baffled. I rescanned both images multiple times.

Have you ever seen the same?

The flawed scan’s negative is (as) flat as the other. The images are not on the same strip of film. I am using a Plustek 8300ai.

 

[koraks]

Let's see a scan then.

 

[250swb]

File size and sharpening? More sharpening (which shouldn't be done in the scanner software anyway) is needed for a larger file than a small file to achieve a similar look. In fact if anything like sharpening or dust and scratch removal is switched on, switch it off and try again.

 

[Taylor Nankervis]

Post a sample scan, plus a screenshot of the dialogue boxes so that your settings can be examined.

Sharpening isn't normally required, and some settings e.g. ICE, deblur, etc., can give a false impression that either the preview or the actual scan is blurry.

 

[Ivo Stunga]

Using Plustek 7600i I turn every automation and sharpening off and do multiscan that helps to lift shadow detail.
Auto dust removal via IR is off too as that 1) works just on dye-based/color images and 2) introduces softness.
This way my scanner basically just provides a "raw" tiff for me to edit in my post app of my choice.

Haven't had sharpness issues at all. If anything, this hyperfocal scanner picks up too much dust and defects, exaggerating them.

 

[Saganich]

I've come to understand that differences that are not noticeable under 5x mag on a negative are noticeable on a full size scan or print. Usually I go back to the loop and see if there really is no difference, which given two images taken at different times on different film...there are many differences.

 

[Certain Exposures]

Let's see a scan then.

Okay, I will follow up over the weekend. I'm going to rescan and take a few sample shots on the light table. I have several rolls to scan with more examples.

File size and sharpening? More sharpening (which shouldn't be done in the scanner software anyway) is needed for a larger file than a small file to achieve a similar look. In fact if anything like sharpening or dust and scratch removal is switched on, switch it off and try again.

I turned off sharpening and scratch removal in SilverFast 9. I'm scanning at 3200 DPI.

Post a sample scan, plus a screenshot of the dialogue boxes so that your settings can be examined.

Sharpening isn't normally required, and some settings e.g. ICE, deblur, etc., can give a false impression that either the preview or the actual scan is blurry.

I will - see my first reply above.

Using Plustek 7600i I turn every automation and sharpening off and do multiscan that helps to lift shadow detail.
Auto dust removal via IR is off too as that 1) works just on dye-based/color images and 2) introduces softness.
This way my scanner basically just provides a "raw" tiff for me to edit in my post app of my choice.

Haven't had sharpness issues at all. If anything, this hyperfocal scanner picks up too much dust and defects, exaggerating them.

Are you also using SilverFast 9? I turned off sharpening and scratch removal. I just use multi-exposure for black and white.

I've come to understand that differences that are not noticeable under 5x mag on a negative are noticeable on a full size scan or print. Usually I go back to the loop and see if there really is no difference, which given two images taken at different times on different film...there are many differences.

That's unfortunate. Several shots look ok on the light table but poor in the scans. I'm hoping I just need more practice with this kit.

 

[grain elevator]

Can you see grain or some semblance of it? Is dust resolved sharply? If not it is probably an issue with scanner focus.

 

[Certain Exposures]

Here is a sample scan of a frame. I will upload a screenshot of my SilverFast dialogue box later when I'm scanning again:

Please excuse the clutter.

Lens: Zeiss 50mm Planar F2 ZM, F2 @ 1/125.

Film: Ilford HP5 pushed to 1600 in Kodak HC-110 dilution B from concentrate.

Support: Tripod and shutter release cable.

Focus point: Focused on the word "Ilfostop."

Scanner: Plustek 8300ai. No sharpening.

Editing: I added contrast to my liking and did some burning in Photoshop.

I have two frames of two different road signs. Both look tack sharp under a 5x loupe on the light table. The text in one image is tack sharp in the scan at 33%. The other image's text shows noticeable blur/'doubling' at 33%. I'm baffled. I rescanned both images multiple times.

Have you ever seen the same?

The flawed scan’s negative is (as) flat as the other. The images are not on the same strip of film. I am using a Plustek 8300ai.

So far I haven't come across another example as obvious as this one. There are a few frames that do seem a bit sharper on the film though.

 

[Les Sarile]

Here is a sample scan of a frame. I will upload a screenshot of my SilverFast dialogue box later when I'm scanning again:

Please excuse the clutter.

Lens: Zeiss 50mm Planar F2 ZM, F2 @ 1/125.

Film: Ilford HP5 pushed to 1600 in Kodak HC-110 dilution B from concentrate.

Support: Tripod and shutter release cable.

Focus point: Focused on the word "Ilfostop."

Scanner: Plustek 8300ai. No sharpening.

Editing: I added contrast to my liking and did some burning in Photoshop.



So far I haven't come across another example as obvious as this one. There are a few frames that do seem a bit sharper on the film though.

The image you posted looks to be very small for a 3200dpi scan making it impossible to assess critical focus. Since there appears to be areas that are in focus, it is still hard to tell.

Your aperture at F2 may not have been sufficient to make sure more of the target to be in focus.

BTW, when I have to optically evaluate a frame to be in focus critically, I use a 40X magnifier setup. I believe a film grain focuser is between 10X to 25X? This magnification just about matches what can be achieved by a Coolscan's 4000dpi setting.

Carson 40X film magnifier by Les DMess, on Flickr

With this setup, I was able to settle with a customer that the softness of the results I provided him with the Coolscan was not because of the scanner.

 

[Certain Exposures]

The image you posted looks to be very small for a 3200dpi scan making it impossible to assess critical focus. Since there appears to be areas that are in focus, it is still hard to tell.

Your aperture at F2 may not have been sufficient to make sure more of the target to be in focus.

BTW, when I have to optically evaluate a frame to be in focus critically, I use a 40X magnifier setup. I believe a film grain focuser is between 10X to 25X? This magnification just about matches what can be achieved by a Coolscan's 4000dpi setting.

Carson 40X film magnifier by Les DMess, on Flickr

With this setup, I was able to settle with a customer that the softness of the results I provided him with the Coolscan was not because of the scanner.

What size image did you expect to see? Should I post at a higher resolution? That one is 1500 pixels wide.

I've never seen a 40x loupe before. I use a 5x and a 10x.

 

[Certain Exposures]

Note: I haven't posted the road sign frame here yet because I'm planning to rescan it and share some light table shots of it when I get back. I only posted Ilfostop shot above as a sample of my scanning.

 

[_T_]

I’m not exactly sure what I’m looking at in the image you posted. I think it’s a scan of an entire 35mm frame? But it appears to have been scanned in focus. Otherwise the grain of the HP5+ would be blurrier.

I think it would be clearer if you posted an image of an entire frame together with an image of a 100% crop of the focus point of that same frame.

But at this point, from what I’m seeing, you don’t appear to have a problem with the focus of your scanner.

I’m not exactly sure why it appears to be sharper on the light table except that it’s possible you are seeing the frame at a lower magnification with your loupe than you are on the screen with the scan.

At 3200dpi your scanner would produce a file that would be magnified about 12x when viewed at 100% and at 7200dpi the file would be magnified about 24x when viewed at 100%. This could be compounded by the fact that, at either resolution, the scan is not really getting the stated amount of information out of the physically extant information contained in the negative. The actual resolution of the system being somewhere below the nominal resolution you're setting in the scan software prompt due to optical effects.

That and maybe a little bit of the psychological effect called change blindness, which makes it difficult to evaluate differences between two subjects when there is even a very small amount of time separating the viewing of one and then the other, would be my best guess without some further information.

 

[Certain Exposures]

I’m not exactly sure what I’m looking at in the image you posted. I think it’s a scan of an entire 35mm frame? But it appears to have been scanned in focus. Otherwise the grain of the HP5+ would be blurrier.

I think it would be clearer if you posted an image of an entire frame together with an image of a 100% crop of the focus point of that same frame.

But at this point, from what I’m seeing, you don’t appear to have a problem with the focus of your scanner.

I’m not exactly sure why it appears to be sharper on the light table except that it’s possible you are seeing the frame at a lower magnification with your loupe than you are on the screen with the scan.

At 3200dpi your scanner would produce a file that would be magnified about 12x when viewed at 100% and at 7200dpi the file would be magnified about 24x when viewed at 100%. This could be compounded by the fact that, at either resolution, the scan is not really getting the stated amount of information out of the physically extant information contained in the negative. The actual resolution of the system being somewhere below the nominal resolution you're setting in the scan software prompt due to optical effects.

That and maybe a little bit of the psychological effect called change blindness, which makes it difficult to evaluate differences between two subjects when there is even a very small amount of time separating the viewing of one and then the other, would be my best guess without some further information.

Thanks, it's a scan of an entire 35mm frame. I'll share other frames another day. Hopefully you're right about the scanner focus!

 

[koraks]

it's a scan of an entire 35mm frame

Well, not an entire frame given the aspect ratio. Did you only crop the sides, or also top & bottom?

Do you have prior experience with this scanner? Keep in mind that scanned negatives virtually always require sharpening especially after resizing in order to look crisp.

 

[Certain Exposures]

Well, not an entire frame given the aspect ratio. Did you only crop the sides, or also top & bottom?

Do you have prior experience with this scanner? Keep in mind that scanned negatives virtually always require sharpening especially after resizing in order to look crisp.

Oh, there's a slight crop to the sides to fit the 2x3 aspect ratio.

Yes, so far the scanner has been okay. I decided to turn off auto sharpening in SilverFast because I was not enjoying the results. Maybe I should go back to auto sharpening.

 

[koraks]

Ah, I see. I always sharpen up digital files manually, to taste and depending on the size, nature of the file etc. But for most purposes I find that some degree of sharpening is beneficial. So far I see nothing apparently wrong with your scan; it looks fine to me.