2 Attachment(s)
Help solving film holder light reflection
I am looking for suggestions for solving what I believe is a light reflection off my Fidelity Elite film holder onto the film when using wide angle lenses (please see photos below). When shooting an image with a strong out of frame light source occasionally I will get a highlight on the film. I know that more accurate placement of a hood or french flag would help this, but I am also considering painting the edge of the film holder with an ultra matt black paint to help as well, such as black 2.0. I am wondering if anyone has tried this before, or has a suggestion for something I may be missing. Thank you.
Attachment 170570
Attachment 170571
Re: Help solving film holder light reflection
It could be a lot of things. Can you see it in the scene? Does it only happen with one holder?
Better to determine the cause than using "trail and error" approaches to a solution.
Re: Help solving film holder light reflection
If this is an extended exposure (and it looks like it is), you may have a strong/er light reflection from some source. But, that requires a test or two to make sure it's not the holder. Hard to say from here.
Les
Re: Help solving film holder light reflection
This light only occurs when I am shooting with my 90mm when there is a strong light source outside the image on the film. In this case it is a bank of windows to the right of the frame. I use wide angle bag bellows frequently and in no other images have had light leaks. Additionally, this will sometimes occur on any side of any Fidelity Elite holder, other than the side with the film loading door. For this image I exposed three sheets in two holders, all images have the same light on them. It was about a minute exposure with reciprocity adjustment, but I have had it occur on shorter exposures. I use other wide angle lenses without this problem, a 58, 75 and 120.
Since the light will come out occasionally regardless of direction of the film holder (i.e. vertical, horizontal from left or right insertion), direction of light source (above or the side), or holder used, I believe it is a reflection of light off the slightly reflective surface of the holder. I am thinking about finding a way to dull the reflective surface, one method may be mat black paint. I am wondering if anyone else has attempted this, or solved this problem another way. One problem with mat paint it is notoriously brittle and may cause a dust problem.
Of course, I probably shouldn't put strong light sources next to the image area, but hey what can I do?
Re: Help solving film holder light reflection
I think you could also just roughen the edges of the holder with a little very fine sandpaper, being sure to clean well afterwards. Unlike paint it won't flake off
Re: Help solving film holder light reflection
Looking at it closely, there seems to be an image of a window or banister within the light leak, that would indicate a pinhole. Have you tried draping your dark cloth over the bellows during exposure?
Re: Help solving film holder light reflection
Quote:
Originally Posted by
Tobias Key
Looking at it closely, there seems to be an image of a window or banister within the light leak, that would indicate a pinhole. Have you tried draping your dark cloth over the bellows during exposure?
Or natural reflection from window glass.
Re: Help solving film holder light reflection
Sure looks like a light leak, with some pinhole or gap forming an image... You can try "exposing" and developing a sheet of B/W, while placing the bright source near the edges (at your normal focusing distances) and looking for fogging without firing the shutter to check... Or a thorough flashlight bellows/body check... (Or a "sun test" with a piece of film loaded in camera, sitting out in the sun for awhile...) And check where lensboards/backs/standards/bellows connections/film holders seat very carefully... # your filmholders and note what shots have the fogging, and check...
Sometimes light will leak at only one narrow angle (that does not happen to line up too often), but when the evil planets align, ...
Steve K
Re: Help solving film holder light reflection
Quote:
Originally Posted by
LabRat
Sure looks like a light leak, with some pinhole or gap forming an image... You can try "exposing" and developing a sheet of B/W, while placing the bright source near the edges (at your normal focusing distances) and looking for fogging without firing the shutter to check... Or a thorough flashlight bellows/body check... (Or a "sun test" with a piece of film loaded in camera, sitting out in the sun for awhile...) And check where lensboards/backs/standards/bellows connections/film holders seat very carefully... # your filmholders and note what shots have the fogging, and check...
Sometimes light will leak at only one narrow angle (that does not happen to line up too often), but when the evil planets align, ...
Steve K
agreed
3 Attachment(s)
Re: Help solving film holder light reflection
I did a bit of testing of my theory and it is a reflection off of the Fidelity Elite film holder when there is a very bright light source not hitting the film area, but striking the perpendicular ledge on the film holder. Every now and then I frame something with a bright light source out of frame, this has happened on only 4 scenes in the past 3 years of about 700 negatives I have shot in that time - so it is rare, but as LabRat said, "when the evil planets align." I will take the camera and demonstrate this with a video and a flashlight on Monday. Below are details of the other three negatives that this occurred on. Better use of a hood or french flag should help, but the tolerances are tight. Now what I need to do is figure out if I can dull the ledge so this does not happen, any thoughts? (FYI, this did not happen on the same holder, my field notes state that this occurred on 5 different Fidelity Elite holders).
Attachment 170603 Large light source directly behind tree, with open canyon behind
Attachment 170604 brighter light coming from top of slot canyon
Attachment 170605 dense trees thin out with sun rising in background
To be fair, a slight reflection also occurs off the black paint inside my Shen Hao HZX 45iiA that is near the film holder, but that is almost always hooded or flagged off.
Also, square shape on the original post photo is coming through the window from another reflection outside, it was on the wall when I took the photo. I know it kind of messes up the conversation since it is there.