Hey everyone,
Am hoping someone might me able to tell me whats going on with these images.
On a few of my scans, im noticing that the borders of the images are incredibly faded. Im trying to work out if this is something that i am doing wrong throughout the scanning and conversion process, or if it just an unavoidable side-effect of having a poorly exposed image.
When metering these images i was unaware that the ISO on my meter was set incorrectly, causing the images to be poorly exposed. I also had some occasional light leaks with this cameras film back, so that may also be a contributing factor.
I am DSLR scanning and at first i though the film holder was leaking light around the side of the negatives during the scanning process, but after some testing and messing with the mask on the film holder im fairly confident that that is not the case. Also being the fact that this was only happening on these 3 incorrectly exposed images, i thought i could rule that out.
It’s possible your scanning light source is reflecting off the edges of the film holder. This can cause extra light to hit the edges of the film next to those sides. It looks like the overexposure pattern is pretty consistent on all the images. You could try scanning a neutral density filter or some other known translucent film with no image to see if it show up. If it does, that would point to the light source or the scanning film holder.
Having said that, it does look like it might be the original film back.
My scanning setup is relatively robust. I am scanning with a Canon R6 MK2, Sigma 105mm 2.8 macro with the lens hood on. Fully blackened room, with very very minimal ambient light coming in from behind black out curtains.
I am using the Essential film holder and a Viltrox L116T. Here is a picture of my scanning setup ( the glass PC side panel is also covered during the scanning to prevent any reflection)
Upon further testing, this is also happening on the negatives from my Fuji GSW690III, which is 100% light leak free.
I have uploaded a raw negative from my Fuji which can be downloaded here if anyone would like to try a conversion themself to see if they get any differing results:
Any assistance would be much appreciated. Thank you.
Hate to say it. But I had this issue when using the Essential film holder with my medium format negatives. It wasn’t all the time, but when it happened, it looked like what you are seeing.
I could never figure out why it would happen. I ended up changing to the negative supply film holder and don’t have the issue anymore.
Wondering if this a current version of this film holder? I had thought that he improved it as it seems that this shading effect can happen sometimes. Maybe try a blank piece of unexposed colour negative film and also mask off your light panel as close as you can without it intruding on your scan.
Plenty of posts like this if you look for them, clearly it doesn’t happen for all users, or all combinations of light panel and lens, but something is going on:
I downloaded your file and converted it in NLP. JPEG rendition of the raw file is provided here. I see no problem with it. I followed the standard procedure for making conversions in NLP: (1) In Lr, straighten the negative; (2) In Lr, take the white balance from an exposed section of the media; (3) in Lr, crop-out everything except the actual photograph. (4) Call-up NLP and click . This indicates that neither your film holder nor the camera are causing light leaks for this photo.
After further testing, i beleive i have narrowed it down to my light panel. I am using the Viltrox l116t. I ended up rotating the light panel by 90deg and noticed that the light bleed then shifted from the sides of the frame to the top and bottom.
This suggested to me that the light panel was struggling to illuminate evenly across the entire width of the panel. That also makes sense as to why i would only notice it on my medium format scans and not my 35mm negatives.
I then ran a test using my iPad pro with the Negative supply backlight app. I still used the EFH with the diffusion panel and these were the results. ( left is original scan with the Viltrox, and right is the scan with the iPad.
This particular negative is a very thin negative which was quite badly under exposed. I used this as the test negative for that exact reason. It demonstrates the light cast / bleed much more noticeably than a properly or slightly overexposed negative. The iPad scan completely eliminated the issue. I was quite surprised as i know the Viltrox panel is a very popular choice.
Speaking to someone else using a very similar panel ( illumination area dimensions, temp and CRI ) just a different brand, they were experiencing the exact same issues that i was. I am waiting to hear back from them as they said they would try replicating my resting with their setup too.
You could simply photograph your light panel on its own, selecting an exposure to give a mid-grey. Then play about by boosing the contrast. This will give you a better indication of the evenness of illumination. See this overview of the Cinestil CS-Lite by Valoi with comparisons with the Raleno PLV-192. Note that Valoi sell the CS-Lite and have chosen it to use with their film holder so as they say…
"If you are unused to looking at light sources like this, it might look really bad. However, this is a very normal result and a very good results for a light in this price range. For comparison, here is a very well regarded light source, the PLV-S192, with the exact same RAW processing settings as the above picture, copied over. As you can see, the pattern is slightly different, but the overall amount of unevenness is about the same. If anything, the CS-LITE wins when it comes to the 6x9 area in the center of the light - only the very edges are a little too bright. The Raleno PLV-192 has more vignetting in the area just within the edge, that the CS-LITE does not have.
We conclude that the Cinestill CS-LITE light will provide essentially perfectly even light for your scanning purposes."
