Pinhole recommendation

[Rayt]

On a whim I bought a Harman Titan 4x5 made by Walker Camera for a road trip to the Southwest and was surprised at the amount of detail in the negs. I don’t own any other Walker cameras but I believe the pinhole is made from the same tough plastic material.

[Greg]

Have been shooting pinhole since the 1980s up to the 11x14 inch format. Beware of commercially available pinholes, especially "laser cut" ones. Some of them are accurate in diameter but cut in too thick of pieces of metal sheet. Also the inside of the pinhole may be not blackened and thus produce a lot of flare from reflections from the shiny sides of the hole. Personally take the time to make my pinholes manually through sheets of brass that the sides of the pinhole have been "ball peened" to a minimum thickness and then easily blackened with a Sharpie. Again beware of commercially available pinholes... In my opinion most are made by non-practicing photographers.

[Tin Can]

Could you be specific on thickness desired. I do have micrometers

Also making the hole and sizing for 11x14

Is India ink good for blackening?

[Havoc]

As thiw as possible but still opaque. Don't fret over it for starters. Pinholes are cheap compared to lenses. It is relatively easy to obtain brass shim 0.1mm or thinner.

The dimensions of the hole will depend on the "focal length" and CoC you want. I used this one on the net: https://www.mrpinhole.com/calcpinh.php

Not so sure about india ink. It has to adhere to metal. There are chemical blackening solutions that can be used. I just bought a pinhole to start, looked fine under the loupe.

[Tin Can]

Thanks Havoc, Post #12 seemed to imply better secret magic

I have made quite a few Pinhoes and their boxes in the last 20 years

I use Mr Pinhole often https://www.mrpinhole.com/

My first LF image was made by Pinhole, all made by hand in a class, I am very familiar with hammering brass and using a needle

I also have bought a few of the fancy Pinholes, they are very affordable

I have a BIG plan and will be ordering a few custom made Pinholes shortly

As thiw as possible but still opaque. Don't fret over it for starters. Pinholes are cheap compared to lenses. It is relatively easy to obtain brass shim 0.1mm or thinner.

The dimensions of the hole will depend on the "focal length" and CoC you want. I used this one on the net: https://www.mrpinhole.com/calcpinh.php

Not so sure about india ink. It has to adhere to metal. There are chemical blackening solutions that can be used. I just bought a pinhole to start, looked fine under the loupe.

[Jim Jones]

Could you be specific on thickness desired. I do have micrometers

Also making the hole and sizing for 11x14

Is India ink good for blackening?

I prefer brass sheet .002 inch thick, with the thickness reduced around the pinhole by the process of making the pinhole. .001 brass is more difficult to work with, and thicker brass is unnecessarily thick. The proper diameter of the pinhole is mostly determined by the focal length, not the film format. The ideal diameter for each focal length will have the smallest CoC. http://www.pinhole.cz/en/pinholedesigner/ is probably the best for determining this, although some people use Mr. Pinhole.

[Tin Can]

Thanks Jim, your last point is news to me, but does make sense

I have used a lot of very thin brass shim stock for other purposes, we had it in yards long rolls, like this

Today I ordered the French made zone plates in 250mm, 500mm and 800mm for testing

I prefer brass sheet .002 inch thick, with the thickness reduced around the pinhole by the process of making the pinhole. .001 brass is more difficult to work with, and thicker brass is unnecessarily thick. The proper diameter of the pinhole is mostly determined by the focal length, not the film format.

[Philippe Grunchec]

Good luck!

[Pere Casals]

I prefer brass sheet .002 inch thick, with the thickness reduced around the pinhole by the process of making the pinhole. .001 brass is more difficult to work with, and thicker brass is unnecessarily thick.

I was thinking in trying with gold leaf, 0.1 micrometers thick, I don't know if it's a good idea...