It's really worth using a better glass cutter. I started with that type when I began picture framing. For not much more, a better cutter will give cleaner, more precise cuts, requiring less work cleaning up jagged corners.

@AdamWelch

8 ай бұрын

Have a recommendation?

Very good idea. I have also completed the work according to your method. It is recommended to use suction cups instead of tape, which is easier and more convenient to operate.

Thank you for this! I was about to order a piece of ground glass for a project I want to experiment with (making a digital back for my Hasselblad)... Was about to drop $30 on a piece of 6x6 cm glass, and instead found this video. I have some old photo frames around with glass in them, as well as some glass tools for doing stained glass work... And i believe i have some silicon carbide grit for our rock grinder! Time to make my own ground glass screen! :D THANKS!!!!

@AdamWelch

Жыл бұрын

Hey that's great to hear. I'll add that given the SLR platform I have no idea how that will affect focus but best of luck! I actually just dropped an Acute Matte in my 500 C/M, made a WORLD of difference. Let me know how it turns out if you don't mind.

@BmcN72

Жыл бұрын

How did it go for you?

I did this with my 8x10 screen. the larger glass made a lot of friction, after some trial and error I used a small metal cap from one of my vermouth bottles I finished the other day and it worked like a charm!

@AdamWelch

2 жыл бұрын

Great information to have! Since this video was made I've acquired a beautiful 8x10 that still had the original GG but eventually I'll be replacing it myself. I'm curious about some chemical etching compounds I've saw at my local hobby shop....

You didn't mention how you got the new ground glass to match the same focal plane as your film / plate holder. This is critical for good focus. I'm guessing your spring back was designed with the glass inset at the focal plane. It's important to place the ground side at the focal plane (usually ground side toward lens). For example, a typical Graflok back has a Fresnel lens between the ground glass and the lens - the spacing added by the Fresnel lens is crucial for the focus to translate well to film. But compared to no ground glass at all, this is undoubtedly "good enough" - I've heard of DIY focus testing done by establishing a scene with items of known distance, e.g. focusing on a playing card with several cards stacked in direct contact in front and behind. Whichever card is in focus tells you how far off your ground glass is from the true film / plate plane. You can use those cards or similar paper stock as shim material.

Just tried this, if you mix a bit of oil in it moves around easier. I got good results, had to keep trying to get the edges.

@georgesmith4509

2 жыл бұрын

g'Day Geoff Pedder, you will find ordinary kitchen detergent works equally as well and much easier to clean of.

great work Adam. i did the same for a 10x15 cm old Ideal - used the carbide method, its just as messy but easier to clean (as you mentioned)

@AdamWelch

3 жыл бұрын

Very nice! I'm more than likely going to eventually grind this one down a bit more fine after I get the Fresnel installed.

Great vid! Thank you.

thank you

The ground surface side must be mount to the interior minuto 15:00 its seem to be unproper position

Good work , I have a question please! .. wich side did you put the grounded glass from the inside or out side?

@AdamWelch

2 жыл бұрын

The ground glass seats from the outside. It rests in the cutout and is held in place using the four tabs.

@victorobeid1982

2 жыл бұрын

Thanks you very much.

@victorobeid1982

2 жыл бұрын

I have another one. The sid you grounded , fases you or the the lens?

@AdamWelch

2 жыл бұрын

Generally the ground side (rough side) faces towards the lens. If you are using a Fresnel in addition to the ground glass that will face towards the lens as well.

@victorobeid1982

2 жыл бұрын

Thanks again ,really thank you.

Thanks for sharing your build, I'm currently working on rebuilding a Mamiya RB67 (Bellows are ruptured and Focusing screen is missing). I was going to buy both on ebay, but seeing this video has given me a totally new path to explore. Here's my question: Can i use a 5mm acrylic sheet for the ground glass?

@AdamWelch

4 ай бұрын

As far as making a ground glass from acrylic, absolutely. In fact, my 11x14 camera has an acrylics screen. However, when it comes to focus screens for reflex-type cameras, it becomes very important for the geometry and distances to be precise between the mirror and screen. All that to say that while it would certainly be possible to cut, grind, and fit a self-made focus screen for your Mamiya you might run into problems with focusing depending on the thickness of the acrylic and other little miseries due to fitment.

@IdowuAsumah

4 ай бұрын

Hi Adam, thanks for prompt response. I recognize the complexity and I’m willing to explore. I’ve actually just made my first iteration.

@AdamWelch

4 ай бұрын

@@IdowuAsumah That's fantastic. I hope it goes well and feel free to share your progress. I'd be interested to know the results.

@IdowuAsumah

4 ай бұрын

Thanks. I sure will. Could you answer me a few questions: 1) Why notch the corners of the glass? 2) What sandpaper grit would you recommend? I used 320 grit and I can see loads of scratches on the screen. 3) Do you have a focusing screen for a medium format body? Would you mind sharing images and maybe measurements to give me some direction? This is my the first time I’m handling a medium format film camera so I don’t really have much reference to call on.

@AdamWelch

4 ай бұрын

@@IdowuAsumah No problem. Answers below. 1) The notches are to let air escape from the bellows. Due to the compression of the bellows it builds up pressure. It's essentially Boyle's Law, larger the bellows, the more pressure is created due to the increased volume. That's why to don't see notches on smaller camera bellows generally under 5x7. 2) Unfortunately, that sand paper is FAR too coarse. I honestly doubt any grade of sandpaper would be fine enough for the softer acrylic. You'll likely need something upwards of 1000 grit, something like a lapping compound. To me, even this ground glass was a bit too coarse for my taste. If I ever make another one I'll like go with something much finer than what I used here. 3) You might know this already but there is no such thing as a generic screen for "medium format" cameras. The cameras are all technically medium format, but all their screens are proprietary. Meaning your RB67 (6x7 format) has an entirely different screen than my Hasselblad 500 C/M (6x6 format), and a Rolleiflex TLR has an entirely different screen than the Hasselblad even though they are both 6x6. You would need the exact measurements that would fit the screen housing for the RB67 or preferably another screen to copy.

Off topic, but what is the fountain pen you are using? Thanks!! And thanks for the video - really helpful.

@AdamWelch

Жыл бұрын

Ha, no worries. I actually had to look it up but it's an EXTREMELY cheap fountain pen I got off Amazon. My first one actually. Got it to just see how I'd like it and it's been my everyday pen for over three years now. Never bought another one. This is the one I have. amzn.to/3Y6OwgO They only had black at the time but apparently they've went crazy with the colors.

I'm surprised that you didn't use you square for to mark the composition lines. also you say you are waiting for a new bellows for "Josephine". Why not make one the material is fairly readily available in Australia, so it should be much easier to get in your part of the world.

@AdamWelch

2 жыл бұрын

I'm not sure, for all practical purposes, the square would have made a difference. This camera is a savage story anyway. The original bellows and frames were lost by the Postal Service on the way to the UK for replacement. The total price for the replacements plus install was under $200US from an highly experienced bellows maker which was more than worth it for me. Do you make your own bellows? At any rate, Josephine is now with a new owner in Hong Kong.

@georgesmith4509

2 жыл бұрын

@@AdamWelch Making a bellows is not that hard it requires more patience than technical knowledge. there are several good tutorials on you tube if you wish I'll try and link one to you. As for the square, I suspect if it was closer than a rule I'd do the same thing. And thanks for the tip about the lead pencil.

@AdamWelch

2 жыл бұрын

I'm asking you if you've ever made a set of bellows?

@georgesmith4509

Жыл бұрын

@@AdamWelch thought I replied to this question yes , a tapered one for a resto of a premier No1 (c1890) it was tapered . Also made a octagonal one for a10" collapsible reflecting telescope.

Would this work for a 4x5 large format?

@AdamWelch

Жыл бұрын

Yes

Can i assume this will work for 6x6 for example?

@AdamWelch

Жыл бұрын

It would technically work but I'm certain the thickness of whatever glass you use would affect the focusing due to the mirror.

@AdamWelch

Жыл бұрын

IF you're using an SLR camera that is.

@BmcN72

Жыл бұрын

But the GG is on top of the fresnel. So not interfering with mirror

@AdamWelch

Жыл бұрын

The way focusing works with an SLR is by replicating the focal distance between both the film plane or sensor and the mirror / viewfinder/prism. If the distances are off due to the thickness of the glass then you will be seeing a different picture through the viewfinder than you will be projecting onto the image sensor or film. Perhaps you should start off by telling me specifically which camera you are asking about and we can go from there.

@BmcN72

Жыл бұрын

@@AdamWelch bronica s2a

Where is Fresnel lens?

@AdamWelch

Жыл бұрын

The Fresnel was placed behind (lens side) of the ground glass.