8x10 photography and diffraction

[Drew Wiley]

A wet plate is ZERO pixels. That's why I like it, slides shows too. Digital projectors were for those really boring Powerpoint presentations at sales meetings before I retired - worse than Aunt Maude showing Kodachrome slides of her vacation to the donut factory in Peoria taken the previous summer.

[Bernice Loui]

All this text goes back to the question of what is "Art", why Art is IMPORTANT to the human family and human condition.
Question of 8x10 and Diffraction is just one grain of sand on the beach of expressive image making.


Bernice

[Fred L]

question for the those who use 2x sided tape. to remove the sheet, do you simply pop one side out the rail to peel it off the tape, or is there a better method ? also one would want tape with minimal sticktion ?

tia

fred

[Vaughn]

I slid a finger under the film and popped it off the tape, then slid out the film as usual. I used a 3M tape that had high tack strength on one side and low on the other.

[Andrew O'Neill]

Film sag did you say? Double-side tape. Bob's your uncle.

[Bernice Loui]

Depending on the thickness of the tap, amount applied and .... lifts up the film altering it's focal point position.
Adhesive film holders were once a Sinar item. Linhof made a vacuum film folder.

Just another trade-off.


Bernice

Film sag did you say? Double-side tape. Bob's your uncle.

[Drew Wiley]

It has to be the right kind of tape! - 3M no. 9415PC - permanent adhesive on one side, repeatedly repositionable Post-It adhesive on the other side. 9425 has also been successfully used. Both are 2-mil thick. Modifying holders is simple if you have typical plastic Lisco or Fidelity holders. Just take a sharp box knife, a steel straightedge, and slice the film-retaining fin from each side (not the darkslide retainer). Practice on a funky holder first. After your tape strips are carefully placed and permanently pressured down, remove the top liner. Film is carefully aligned to the bottom end position then gently dropped down. It's easy with practice. Be careful not to let dust build up on the adhesive so that it will remain effective over the long run, potentially many years.

[Michael Kadillak]

Depending on the thickness of the tap, amount applied and .... lifts up the film altering it's focal point position.
Adhesive film holders were once a Sinar item. Linhof made a vacuum film folder.

Just another trade-off.


Bernice

Been shooting primarily 8x10 for 15 years and never ever have I had a situation where I witnessed or could see in the negative / print the adverse effects of film sag on 8x10 even shooting straight down at an image. Sharp as a tack. Similarly I have never seen a problem with this on 11x14 although I have to admit that I have never taxed the conventional horizontal +/- 20 degrees with he 11x14. Why be concerned about something that by its own implementation could induce a problem with double stick tape?

[Bernice Loui]

Try using a Schneider 480mm f4.5 Xenar with a taking aperture of f8 on sheet film 5x7 or larger, then make an enlargement of up to 4x. Then do a close up inspection of less then 12" away and inspection with a 4x loupe magnifier on the print.

If the taking aperture is f22 and smaller then contact printed a taking aperture of f90 on 8x10 and larger is not a problem.

All relative and dependent on expectations and demands of the image maker.



Bernice

Been shooting primarily 8x10 for 15 years and never ever have I had a situation where I witnessed or could see in the negative / print the adverse effects of film sag on 8x10 even shooting straight down at an image. Sharp as a tack. Similarly I have never seen a problem with this on 11x14 although I have to admit that I have never taxed the conventional horizontal +/- 20 degrees with he 11x14. Why be concerned about something that by its own implementation could induce a problem with double stick tape?

[Vaughn]

I have had many 8x10 negatives adversely affected (as in unusable) by film movement during exposure, but this is over a 25 year period in conditions that might be different than Michael's...such as 10 to 30 minute exposures in cool damp climates. But most of them were due to the film shifting in the holder during the exposure, not sagging/popping. Giving the film holder a bump with the heel of my hand before inserting the holder into the camera is now providing protection against that...thus I could do away with the tape.

I have a boatload of 11x14s to develop, so hopefully I will not see any problems with those.