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View Full Version : Ground glass gridlines - out of alignment.



walter23
27-Dec-2006, 12:17
How does one go about drawing up perfect gridlines for the ground glass? Do you just draw them parallel to the edges of the glass?

I have this shen hao that I got a couple of months ago, and the lines are not parallel to the edges of the glass, and likewise they don't line up with the film edges. The consequence is that it's a royal pain in the butt to shoot anything that requires tight control of horizontal or vertical lines, including architecture and anything with a straight horizon.

Should I just order a satin snow glass and draw my own lines parallel to the edges of the glass, or is there a more rigorous way to calibrate them (like by burning up polaroids while shooting a grid on paper or something?) What do you guys do? I presume that because the woodwork defines how the film holder sits, you would just have to align the lines with the woodwork (which they are not at the moment).

Should I just order a maxwell screen and get him to draw the lines?

Michael Gudzinowicz
27-Dec-2006, 13:00
My grid lines are drawn with a thin lead pencil, a T-square, and a ruler to mark the spacing.

In practice (for instance photographing a building), I ignore the lines and use the bubble levels of the tripod head to set the back vertical and horizon level, and then add movements as desired. The tripod head levels are adjustable, and are calibrated to the camera back using a larger more sensitive level.

C. D. Keth
27-Dec-2006, 13:15
I just remove the back and lay it on top of a white piece of paper or a light table. Then, use blue masking tape to mark the outermost edges of the frame directly on the glass, using the woodwork as your guide. Then you can remove the glass from the back, turn it over and use a fine lead pencil and a straight edge to mark the lines.

Dave Parker
27-Dec-2006, 13:36
I have templates on my website that are actually for 4x5 screens, that are real sized, you just have to lay the screen on the grid pattern you print out and use a ruler to trace the grid onto the ground side of the glass, myself personally have never found a need for a grid, I use my levels, I have never ran into any kind of work that required minute precision and the actual perspective of the grids on the glass will vary in reference to subject matter, depending on the magnification of the lens being used.

But again the grids are there for download on our website and they are free. You just need to make sure you have a .pdf reader to print them out.

Dave Parker
Satin Snow Ground Glass

walter23
27-Dec-2006, 14:18
Alright, I guess working with the bubble levels makes sense. The bad grid is definitely an encumbering distraction, so I'll have to get a replacement glass. Maybe a satin snow from badger if they've got 'em in stock.

I think as long as I have a couple of straight line references and maybe frame markers for the 4x5 and polaroid frames I'll be happy. No roll back right now. I'll see what you've got in .pdf format Dave.

Thanks

Turner Reich
27-Dec-2006, 15:51
Why do some camera come with the grid lines put on them by the factory? Don't most new cameras have them. Could the grid be masked out with tape and spray painted? Why is the Satin Snow advertisement shown with grid lines if they are not necessary? A lot of questions that I have been thinking about. Maybe the ad as shown in the Emulsion magazine should come with a disclaimer: "grid lines for illustration purposes only, screens come blank so you can pencil your own lines to suit you".

Bob Gentile
27-Dec-2006, 15:52
"... Maybe a satin snow from badger if they've got 'em in stock..."
Don't believe Badger carries them. Do they, Dave?

Try http://www.satinsnow.com/.

Michael Gudzinowicz
27-Dec-2006, 16:36
Why do some camera come with the grid lines put on them by the factory?

Well, they do give the impression of "precision" until you learn to ignore them.

There are a couple of situations where they may be useful. The first is if you're doing copy work and forgot your mirror to set planes parallel the easy and accurate way. Another application is simply to use grid lines (for instance, 1/2" apart) to quickly measure image size for macro work to determine exposure compensation.

Dave Parker
27-Dec-2006, 16:57
Don't believe Badger carries them. Do they, Dave?

Try http://www.satinsnow.com/.

Hi Bob,

Actually Badger has purchased from us for stock and they are listing them on the website, I will be shipping them more stock after the first of the year as well, but they should still have some in stock at this time. There will also be a couple of other companies that will be stocking our glass after the first of the year, in addition, I have almost perfected a new way to grind the glass, that hopefully will allow quicker turn around times next year. Currently Badger is only carrying the 4x5 for the shen, which will actually fit any camera that is a true 4x5

Dave

Dave Parker
27-Dec-2006, 17:04
Why do some camera come with the grid lines put on them by the factory? Don't most new cameras have them. Could the grid be masked out with tape and spray painted? Why is the Satin Snow advertisement shown with grid lines if they are not necessary? A lot of questions that I have been thinking about. Maybe the ad as shown in the Emulsion magazine should come with a disclaimer: "grid lines for illustration purposes only, screens come blank so you can pencil your own lines to suit you".

Turner,

The logo is different than the product, there is no reason for a disclaimer, I have for three years now, stated, we do plain ground glass. It is an identifiable logo, that is immediately identifiable with the large format camera.. One other thing to remember, I don't put out screens with my logo on there either, which if I go to a grid system, I will have to raise the price over 50% and I will put my name on the screen...as do camera manufactures, to me, that is not something I want to do.

And to be truthful with you, the grids that are currently being offered, are always done by the camera manufacture, most of the time the spacing and patterns are copyrighted and patented by the actual camera manufacture, not the company making the glass, ground glass companies don't normally do grids on screens, I was supplying the Deardorff glass for a while and Jack, had his own grids he was having another company silk screening for him, as does Canham, Sinar, and a host of others, sometimes, people really over think things, especially when they don't have the whole scoop on how things work.

At this time, I really have no interest in silk screening glass, I can't keep up with the amount of plain glass orders we get, let alone set up a complete new business, the cost factors would change the price of our product dramatically and with market research, I don't feel I would have a competitive product any longer, I don't really believe, it matters that much at all, and I have been shooting for a living for over 30 years now.

Dave

tim atherton
27-Dec-2006, 18:35
Some cameras come with plain ground glass - no grid-lines. Grid-lines can be a hindrance to composition.

And they are as easy as anything to make with a pencil and a home printed template if you really need them

walter23
27-Dec-2006, 19:09
Grid-lines can be a hindrance to composition.

I do agree with that, but there are times that they are quite useful as well. It's easy to ignore them - it's harder to imagine them :)

Anyway, I would rather have no lines than lines that aren't parallel to the film edges. I've come to realize that they're worse than useless in this crooked configuration.

Dave Parker
27-Dec-2006, 19:12
Walter,

With a bit of alcohol, a scotch brite pad and some elbow grease often times you can remove the grids that are screwed up and then trace them back on the screen correctly.

Dave

Turner Reich
27-Dec-2006, 23:01
Wouldn't a Scotch Brite pad scratch the glass Dave? Have you thought of making a screen protector for the Satin Snow?

Dave Parker
27-Dec-2006, 23:15
Wouldn't a Scotch Brite pad scratch the glass Dave? Have you thought of making a screen protector for the Satin Snow?

Turner,

No a scotch brite pad will not scratch the glass, normally something softer than glass will not scratch it, scotch brite pads are very soft plastic material, I use scotch brites , hot water and dawn dishwashing liquid to clean all of our screens before shipping.

I have thought about the screen protectors, but really at this time, don't have the time to do it, I am currently a minimum of 8-12 weeks out on orders, just not enough time to put another product into the mix.

Believe me Turner, I have thought of just about anything that can be thought of that concerns our products.

Dave

Bob Gentile
27-Dec-2006, 23:21
"... Badger has purchased from us for stock and they are listing them on the website..."

That's good news! Now you just have to keep pace. Ha!

Brian Ellis
28-Dec-2006, 00:55
I find the grid lines (and a geared tripod head) invaluable in aligning windows, doors, and similar square or rectangular objects in architectural photography. I can't imagine doing that kind of work without them.

Jim Jones
28-Dec-2006, 07:13
I agree with Brian, and find lines useful in copy work and scenic photography, too. The lightly engraved lines on my screens are less intrusive than most printed lines. Tilted lines on a screen are still usable if one crops a little more than the rebate area from the print.

Turner Reich
28-Dec-2006, 15:23
I have all of the screens for my medium format camera and I only use the center focus screen. I have the screen with grids but have never used it. With a view camera I use the screen edge since my screens don't have grids. In general practice grid screens are not necessary.

GPS
28-Dec-2006, 15:35
Couldn't you just cut the bottom side so that the grid agrees with the woodwork edge?