I have two half plate 1890s Thornton Pickards that now have Kodak plate sourced focusing screens too! Thank you for including them, I'm a firm believer in not wasting anything :-)
Enjoy the repairs and advice. On the last point what is the difference between a lens for 4x5 and 7x5? Can you put a 210mm for 7x5 on a 5x4? Sorry if this is a daft question, I’m news at this .
Okay, with large format the first thing to consider is does the lens have a big enough 'image circle' for your format size to fit comfortably inside it. So for example 7x5 fits pretty well within my Schneider-Kreuznach Symmar 210, so it follows that the smaller format 5x4 will fit with even more wiggle room - or should I say 'movements' room! All you need to fit a lens that covers 5x7 onto a 5x4 camera is a suitable lens board. Of course the angle of coverage changes, so a 210 is a standard (same as 50mm on 35mm film) focal length - but a short telephoto on 5x4 ... in fact a perfect portrait lens :-)
Good video! I've got a couple of questions: 1) Which thickness should the glass be in order to depict the true focus accurately? Or this isn't the case. because the image is formed on the inner (towards the lens) side of the glass, which is the focal plane? 2) Should the glass be grinded on both sides, or only on the side towards the viewer? Sorry, if those are kind of stupid questions, I'm not really into large format photography, I'm just building my own panoramic camera and I want to figure out how I would make the ground glass system to get a precise focus. Thanks!
As you have said, the image forms on the inner surface, so should not really matter. I used old glass neg plates in this vid ... I've also used 2mm picture glass with no issues. I wouldn't go too thick as it won't fit clips and diffraction may be an issue if one goes mad on thickness. Grind the glass only on one side and that side goes away from the viewer. The most important thing is that the ground side is EXACTLY in the plane the film will occupy.
@@ashsphotolounge thank you for the answer, this clarifies a lot for me now. Got it - the grinded side is the one inside the camera (which is the focal plane).
Brilliant use of redundant glass plates - glad I included them now - nearly didn't!!
I have two half plate 1890s Thornton Pickards that now have Kodak plate sourced focusing screens too! Thank you for including them, I'm a firm believer in not wasting anything :-)
Very helpful and I love the re-purposing of the half plates. Shame they weren't usable for taking images but everything has a shelf life :)
I tried exposing a couple ... however mould from years of storage had literally 'eaten' most of the emulsion - sad but there you go.
Thanks for the info!!!
No problem Jim
Enjoy the repairs and advice. On the last point what is the difference between a lens for 4x5 and 7x5? Can you put a 210mm for 7x5 on a 5x4? Sorry if this is a daft question, I’m news at this .
Okay, with large format the first thing to consider is does the lens have a big enough 'image circle' for your format size to fit comfortably inside it. So for example 7x5 fits pretty well within my Schneider-Kreuznach Symmar 210, so it follows that the smaller format 5x4 will fit with even more wiggle room - or should I say 'movements' room! All you need to fit a lens that covers 5x7 onto a 5x4 camera is a suitable lens board. Of course the angle of coverage changes, so a 210 is a standard (same as 50mm on 35mm film) focal length - but a short telephoto on 5x4 ... in fact a perfect portrait lens :-)
@@ashsphotolounge many thanks for help and advice
Probably an obvious one, but can I also use sanding paper mounted to a flat _thing_ or would this create an uneven surface?
Sandpaper would not really grind the screen - more 'scratch it up a bit' and as you said, it would not do so in a 'flat' way.
Good video! I've got a couple of questions: 1) Which thickness should the glass be in order to depict the true focus accurately? Or this isn't the case. because the image is formed on the inner (towards the lens) side of the glass, which is the focal plane? 2) Should the glass be grinded on both sides, or only on the side towards the viewer? Sorry, if those are kind of stupid questions, I'm not really into large format photography, I'm just building my own panoramic camera and I want to figure out how I would make the ground glass system to get a precise focus. Thanks!
As you have said, the image forms on the inner surface, so should not really matter. I used old glass neg plates in this vid ... I've also used 2mm picture glass with no issues. I wouldn't go too thick as it won't fit clips and diffraction may be an issue if one goes mad on thickness.
Grind the glass only on one side and that side goes away from the viewer. The most important thing is that the ground side is EXACTLY in the plane the film will occupy.
@@ashsphotolounge thank you for the answer, this clarifies a lot for me now. Got it - the grinded side is the one inside the camera (which is the focal plane).
@@mikelast5637 You got it 🙂