Posts

Showing posts with the label camscan

Zen and the Art of Camera Scanning

Image
My article   Zen and the Art of Camera Scanning or The Brief History of Vlads Test Target  is now live on 35mmc.com

How to Use “Vlads Test Target” for Camera Scanning

When scanning film with a digital camera there are only two absolute musts in regards of captured image: it  should be uniformly sharp and focused from the edge to the edge.  Those two qualities can only be achieved when:  the film holder is absolutely parallel to the camera's sensor plane (and keeps film absolutely flat) and you need a lens which is capable of faithfully reproducing your image at 1:1   scale ( or around that value depending on the camera sensor size and film format)    The first requirements can be achieved by carefully positioning and fine-tuning the camera so that when the image to be captured is in focus, it neatly fills the camera frame, and the center and all the corners are equally sharp. The "Vlads Test Target" (Google it!)   has been designed specifically to allow visual control and the best alignment detection. The Vlads Test Target film strips are so sharp that even the slightest loss of focus causes image edges in the...

Digitize Your Film with Confidence - Introduction Page

Image
In this innovative offering, the ten USAF 1951 test patterns are strategically placed throughout the 24x36mm film frame - one in the center, and the others scattered across sides and corners. This unique arrangement facilitates a comprehensive evaluation of the sharpness and focus across an entire negative or transparency/slide in one shot.  P hotographers can now accurately evaluate the performance of their lenses and camera systems across the whole frame. This is particularly advantageous for detecting any discrepancies or weaknesses in image quality, which might typically go unnoticed with conventional  single-pattern USAF 1951 target needing to be moved in camera field of view. 24x36 mm target on 35 mm Adox CMS Pro film Clean, nice, sharp corners make or break the great scanned image    Welcome to www.film4ever.digital - the home of  USAF 1951 Resolution Chart on real 35 mm and 120 film aka Vlads Test Target ! New 35 mm targets with extra Siemens stars (202...

How to scan transparencies using tethered camera

Image
I spent all day yesterday scanning my old slides. Here is my approach:   I used 75 W CREE lamp bought in home Depot. While I do have dichro lamp house C760 , I  decided against it to avoid dealing with the heat. CREE lamp was on for hours in the end without any issues. I tethered my  Canon Rebel T4i camera  to my  Windows 10 desktop running EOS utility using some old USB cable ( I suspect cable may affect the connectivity so I always use the same one known to work) and camera was running tethered for hours. I set up everything - lens, holders, light etc in working config. I removed  the slide from the holder so my lens was seeing the light diffuser. I put EOS utility in live view mode and used color picker to white balance camera against diffuser. My live view on screen became gray. I deselected picker to freeze my white balance. Note how Red, Green and Blue channels get aligned with each other. In the EOS r...

How to align camera with the chart

Image
Before the chart with the USAF targets, gray scales, etc. can be photographed, it should be suspended vertically with the decent precision.  The camera should be placed exactly in the middle of the chart, and there is almost no room for error  - the depth of field for 100 mm lens at F8 at 100 inch distance is just 10 inches.  All printouts have been  glued with the rubbing cement  to the foam board ( let's assume the board is flat.)  At the center I have placed a round mirror around 5 cm in diameter attached with the pushpins for easy removal.  In hindsight, I guess I should have gone to an art store ( say Blicks) and bought a prefabricated canvased frame 24x36" for $20 . Now  I have this contraption hanging on a wire against the wall.  How do you make it vertical? I guess you recognize those screws ;-)   I discovered such a thing as a self-leveling (!) laser levels. I bought the cheapest one for $25 which was almost useless, but the nex...