PDA

View Full Version : Silverfast AI ( issue with hot spots in BW ) on Epson V850 4x5



1erCru
20-May-2017, 14:34
Having issues with scanning BW. I literally haven't scanned many BW negatives with Silverfast because each time I get clipped hotspots in the close to pure white areas. It doesn't seem to matter what I do in Silverfasts settings, historgram, curves etc. The issue is persistent.

Epson Scan doesn't have this issue at all with BW negatives. I do like Silverfast for certain color film stocks but BW it seems like either I'm lacking skill or there's an issue with the program.

Really wish Silverfast had a straight scan option with no influence from Negafix.

Pere Casals
20-May-2017, 14:58
Having issues with scanning BW. I literally haven't scanned many BW negatives with Silverfast because each time I get clipped hotspots in the close to pure white areas. It doesn't seem to matter what I do in Silverfasts settings, historgram, curves etc. The issue is persistent.

Epson Scan doesn't have this issue at all with BW negatives. I do like Silverfast for certain color film stocks but BW it seems like either I'm lacking skill or there's an issue with the program.

Really wish Silverfast had a straight scan option with no influence from Negafix.

It would be useful you post a sample image about the problem.

Anyway I'd suggest next test with SF:

> Scan 16 bits per pixel

> Take all dynamic range , from left to right, not only the histogram area.

> Save it in TIFF format (important)

> Open with PS, clip what you want, adjust curves...

1erCru
20-May-2017, 16:40
Thanks for the tips. In taking the full dynamic range... doesn't SF do this by default? All of the endpoint sliders are far left and right.

I'll post a scan segment when I get home

Pere Casals
20-May-2017, 16:56
Thanks for the tips. In taking the full dynamic range... doesn't SF do this by default? All of the endpoint sliders are far left and right.

I'll post a scan segment when I get home

As with Epson scan, SF, by default, selects the range that includes the histogram. If you include all then you'll obtain a dull image, but you can restore a pictoric look in PS.

1erCru
21-May-2017, 12:43
Attempted to work through this issue last night and think I may have found a solution for BW. If Negafix is involved it just doesn't work no matter what I tried. If I reduced the hotspots it ended up effecting the rest of the image deleteriously.

To bypass Negafix I scan in 16bit HDR and invert and work the image with levels or curves. I tried this months ago but my skills weren't that great. I think I initially tried HDR scanning in Silverfast with color and gave up, forgetting that Negafix isn't applied. This may be the trick with Silverfast BW and in a lot of ways just turns it into viewscan.

I'm pretty excited as the scan looks great!

Pere Casals
21-May-2017, 13:07
Attempted to work through this issue last night and think I may have found a solution for BW. If Negafix is involved it just doesn't work no matter what I tried. If I reduced the hotspots it ended up effecting the rest of the image deleteriously.

To bypass Negafix I scan in 16bit HDR and invert and work the image with levels or curves. I tried this months ago but my skills weren't that great. I think I initially tried HDR scanning in Silverfast with color and gave up, forgetting that Negafix isn't applied. This may be the trick with Silverfast BW and in a lot of ways just turns it into viewscan.

I'm pretty excited as the scan looks great!

I only work with TIFF, I try to mantain the scan as raw as possible, without sharpening, etc to edit everything with PS. The feature I use from scanner is Multiexposure for Velvia, and not always. it is what I find straight...

1erCru
21-May-2017, 14:37
So you are saying you don't always use multi exposure on images? I may try toggling it off and see what pops out.

IanBarber
21-May-2017, 14:40
Try changing the shadows and highlight sliders in Negafix, tiny adjustments though and then check the areas with the sample picker tool in Silverfast

Pere Casals
21-May-2017, 14:49
So you are saying you don't always use multi exposure on images? I may try toggling it off and see what pops out.

IMHO MultiExposure is a very valuable improvement in case of high densities in the film: deep shadows in slides and very strong higlights in negatives. IMHO a regular well exposed BW negative won't need ME. IMHO a 1.8D max negative won't benefit much from ME.

1erCru
21-May-2017, 15:38
Yeah , I tried everything it seems. The HDR RAW scan with manual conversion is awesome so far. Just did a 48 bit color scan of an HP5+ 4x5 negative and just used the green channel and the results are fantastic.


Try changing the shadows and highlight sliders in Negafix, tiny adjustments though and then check the areas with the sample picker tool in Silverfast