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View Full Version : Review: Bohema Studio Poly/Acrylic ground "glass"



koh303
11-Feb-2015, 13:36
I just got an 8X10 Acrylic ground glass from Bohema Studio, purchased on the auction site.
The piece was shipped in a padded envelope with no other protection, and i think that is a testament to how strong and resilient this material is.

It is indeed VERY bright, brighter then any GG i have seen, but not sure if i can compare it to a fresnel lens combo. It is about X2 thicker then a glass ground glass, but still sits well in the Deardorff back. BTW - the default size they cut is a perfect fit for this camera (as well as Calumet C1).

Grid lines come as an added extra option, and are standard at 2cmX2cm, i think for future GG's i will ask for either 1" or 1cm, which i think would be more useful for me. In any case, you can ask for which ever grid spacing you like, just be sure to specify.

Will post a photo shortly.

vinny
11-Feb-2015, 13:46
Is it ground or is it a film that's been applied to the plexi?

koh303
11-Feb-2015, 13:55
Ground.

Cor
12-Feb-2015, 04:18
Cannot find this Bohema Studio, do you perhaps have a link ?

Thanks,

Cor

vinny
12-Feb-2015, 05:33
Cannot find this Bohema Studio, do you perhaps have a link ?

Thanks,

Cor
search acrylic ground glass
If I found it, anyone can.

Ari
12-Feb-2015, 06:40
Does it flex at all?
How is fine focusing with a strong (8x or more) loupe?

Cor
12-Feb-2015, 07:18
search acrylic ground glass
If I found it, anyone can.

Finally found it, it wasn't on the .nl site, had to go to the .com site. I am curious too if it flexes, I am interested to replace my glass groundglass without grid of my travel 4*5 Galvin.

Best,

Cor

koh303
12-Feb-2015, 07:41
No flex as far as i can tell, its extremely thick (3mm+)
Will check with a loupe later today and report back. From a naked eye point of view, its better then the cambo glass i have, which i always thought was near perfection.

Colin Graham
12-Feb-2015, 07:51
It would be great if you could follow up with more info when you've had a chance to use it.

Does it warp with temperature changes? Is the smooth side scratch-resistant? What's the grind like- coarse, fine? Any hot spots? Is the grid scribed or drawn? 3mm is pretty thick, any weight saving over glass?

Cor
25-Feb-2015, 01:27
Last night I received the custom made acrylic ground glass from Bohema Studio: very nicely made with fine grid lines and cut out corners which I did not have on my old ground glass. It replaces the rather dim and slightly damaged ground glass of my "light weight" travel 4*5, a Galvin.

Acryl is than a safer option. The acryl is rather thick at 3mm, but it fitted perfectly in my Galvin, it's brighter than the original one, it seems a little bit coarser though. I have not had the change to take it out, but thus far I am pleased with it. Since it's acrylic it will scratch more easily, I do not think it can flex under a loupe (which I do not use, my eye description is such that if I take of my glasses I can focus good on the ground glass)

I have no affiliation with the seller, but since shipping from Poland to The Netherlands is cheap it's total price was attractive (54 usd inc shipping for a custom made acrylic with grid lines (1*1 cm) and cut out corners)!

best,

Cor

Sandy44
25-Feb-2015, 22:13
I was in a pinch and needed a GG for a 9 x 12 Bergheil. I found an old clear plastic case that my Windows 7 installation disk came in when I bought it... I cut out the largest piece of flat plastic with a coping saw. The inside of the case was scratch free and the outside wasn't bad. I started out with 400 grit wet sand paper making small figure eights on the exposed side. I kept rotating it, sanding in the same pattern for about 20 minutes. I moved up to 600 grit wet sand paper and did the same thing. Every once in a while I would stop and wash the plastic with dish soap. Once it dries you can see any areas that need extra attention. Used the 600 grit for about another 15 minutes. Washed it, made sure there weren't any deep scratches I had missed, then moved to 800 grit wet sand paper. I wet sanded the entire surface for another 15 - 20 minutes then washed and dried it. I put a spare blade on my table saw and cut it to size. I wet sanded the sides. Cut two corners and laid on a 2cm x 2cm grid on it with a fine tip permanent marker. It ended up being around 2mm thick and fit great! It has been in 120+ degree temperatures without melting. As long as the dimensions are accurate, you shouldn't get any flex that would distort the image on the focal plane. If it binds, just sand the edges. The image was sharp enough under a 4x loupe to get some pretty good shots. I use it as a back up now, I never have to worry if I bust another piece a GG! Total cost was my time!

axs810
28-Feb-2015, 04:23
How does this compare to a Steve Hopf ground glass? Is it better or just as good in terms of brightness/sharpness? (do images "pop" into focus easily?)

axs810
3-Mar-2015, 05:30
I just got an 8X10 Acrylic ground glass from Bohema Studio, purchased on the auction site.
The piece was shipped in a padded envelope with no other protection, and i think that is a testament to how strong and resilient this material is.

It is indeed VERY bright, brighter then any GG i have seen, but not sure if i can compare it to a fresnel lens combo. It is about X2 thicker then a glass ground glass, but still sits well in the Deardorff back. BTW - the default size they cut is a perfect fit for this camera (as well as Calumet C1).

Grid lines come as an added extra option, and are standard at 2cmX2cm, i think for future GG's i will ask for either 1" or 1cm, which i think would be more useful for me. In any case, you can ask for which ever grid spacing you like, just be sure to specify.

Will post a photo shortly.



:)

gorsescent
13-Jul-2015, 03:44
Hello, folks.

I also purchased a 8x10 acrylic ground glass from Bohema Studio. I use it for my Plaubel Peco Profia 8X10.

I'm very satisfied with the quality of the glass. Before this glass, I used to use a normal ground glass manufactured by Plaubel. It was rather dark as many normal ground glasses for 8X10 cameras are. The new ground glass is brighter than the old one. I purchased it via Ebay. It was only $89 including grids ($79 without grids). It's very well priced but it doesn't mean it's cheap. It's very well made and beautiful.

Also, I like the fact that it's made of acrylic. Many photographers accidentally drop their cameras when working outdoors. Then, if the ground glass of your camera is made of normal glass, it's likely to break. However, I'm sure my ground glass will not since acrylic products are far more durable and shock-resistant than glass.

I haven't tried other ground glasses for 8X10 cameras but I'll recommend this product to all other photographers.

axs810
13-Jul-2015, 06:58
How is focusing with an 8x loupe?

axs810
13-Jul-2015, 06:59
How does this compare to a Steve Hopf ground glass? Is it better or just as good in terms of brightness/sharpness? (do images "pop" into focus easily?)

Anyone?

koh303
13-Jul-2015, 07:31
Anyone?

for 80$ you could find out yourself.

brucep
13-Jul-2015, 07:32
Are they advertising at the moment because I couldn't find them

ScottPhotoCo
13-Jul-2015, 08:04
http://pages.ebay.com/link/?nav=item.view&alt=web&id=151740302787&globalID=EBAY-US

Mark Sawyer
13-Jul-2015, 09:33
I use a home-sanded acrylic focusing screen on my big home-made wet plate backs. With 600-grit sandpaper on a 5-inch random-orbit sander, I made a 14x14 in about 20 minutes. It's not perfect, but it's perfectly adequate; bright enough and fine enough to not be a hindrance or even a distraction while working.

If you go with an acrylic gg, you'll want to have a loupe with a soft rubber base where it contacts the screen, and take special care when cleaning it. Acrylic may not break like glass, but it scratches very, very easily.

K. Praslowicz
13-Jul-2015, 13:37
for 80$ you could find out yourself.

I just broke my 8x10 Hopf GG last week. Haven't heard back on my inquiries for a a replacement. Might take this $80 challenge and report back if I don't get a reply soon. The current backup GG I'm using is horrible compared to the Hopf piece.

gorsescent
13-Jul-2015, 13:38
Hello. I use a 4X loupe manufactured by Peak. The combination of this loupe and the Bohema ground glass is very good.

However, I don't know how it would look with an 8X loupe.

gorsescent
13-Jul-2015, 19:22
>axs810

>do images "pop" into focus easily?

Regarding this point, I don't find much difference between my former old ground glass and the Bohema glass. I think it's a matter of the lens rather than the ground glass.

axs810
13-Jul-2015, 21:06
gorsescent - Hmm ok thanks! One last question - when using the Bohema Studio Poly/Acrylic ground glass do you notice that it scratches easy with use or does it hold up pretty well? This sounds like a really great product if it doesn't scratch like crazy

Jerry Bodine
13-Jul-2015, 21:40
...This sounds like a really great product if it doesn't scratch like crazy

Perhaps it's worth time spent looking for a clear overlay material that will adhere to the acrylic yet peel off if replacement is needed for some reason? Just a thought.

axs810
13-Jul-2015, 21:52
That's a good idea! Thanks!!

Cor
14-Jul-2015, 00:07
As mentioned before I too own a 4*5 Bohemia ground glass, it's very nicely made, but it's thicker than your usual ground glass, so look careful if your camera can accommodate a thicker ground glass. I do not use a loupe ( about the single positive thing about me wearing glasses: taking them off I can focus quite well).

I do find the glass coarser than the other glasses I own, perhaps it's a matter of getting used too, on the plus it's quite bright, and as said cannot break..

good luck,

Cor

gorsescent
14-Jul-2015, 00:42
>axs810

I installed the ground glass on my camera yesterday. Therefore, it's too early to tell if the ground glass scratches easily.

In my experience, the only hard material that touches the ground glass is a loupe. As long as you carefully use a loupe, I suppose no problem will occur.

steveo
14-Jul-2015, 07:03
Very tempting having just broken my Yanke gg. They're about the same price, odd that these don't show up on the .co.uk ebay or I might not have gone with Yankee.

pdh
14-Jul-2015, 08:01
You can get them direct from Poland without going through eBay.
http://svedovsky.com/accessories/acrylic-focusing-screens/

steveo
14-Jul-2015, 10:18
Cheers.

I wonder if a tablet screen protector would work to stop it being scratched.

Jerry Bodine
14-Jul-2015, 10:30
... Is the grid scribed or drawn? 3mm is pretty thick, any weight saving over glass?

Colin, I've not seen an answer yet to the question of the how the grid is fabricated, anyone know? As to the weight saving, the specific gravity of acrylics is about 1.2, and that of glass averages 2.6; so the Bohema acrylic should weigh about 1.2/2.6 = 46% of your glass screen (assuming your screen is also 3mm thick). If your screen is thinner than that, just divide that percentage by the ratio of your thickness-to-3mm. For example, if your screen is only 2mm thick, the 46% climbs to 69% (about a 30% weight saving).

koh303
15-Jul-2015, 04:47
the how the grid is fabricated, anyone know
Laser cut.

Jerry Bodine
15-Jul-2015, 08:09
Laser cut.
Does that mean they are scribed to some depth via laser? How are the lines darkened? An ink of some kind?

koh303
15-Jul-2015, 11:44
laser etched. most modern GG's are made this way, as is yankee.

steveo
16-Jul-2015, 01:37
Just ordered one for my 54 it has to be better than the bit of bullet proof glass currently in place.

axs810
19-Jul-2015, 02:34
anyone want to post a photo of how bright these screens are?

axs810
19-Jul-2015, 16:22
How does this acrylic ground glass compare to a borosilicate ground glass?

Wayne
19-Jul-2015, 20:02
Are you sure they are about the same price? Are you talking about Yanke's 2 in 1 because they look to be about twice the cost.


Very tempting having just broken my Yanke gg. They're about the same price, odd that these don't show up on the .co.uk ebay or I might not have gone with Yankee.

steveo
20-Jul-2015, 05:51
Are you sure they are about the same price? Are you talking about Yanke's 2 in 1 because they look to be about twice the cost.



The one I broke was a simple gg with no fresnel. I think it came to about the same 50 USD this time I have no worries with HM Customs, a Polish import is covered whilst a Chinese one has the risk of handling fees and VAT.

This is similar to the one I purchased, cut to size for $45. 281446143053.

axs810
20-Jul-2015, 21:35
Since no one answered my questions about the acrylic ground glass I decided to order one for myself. When I get it and try it out I'll post my full review of it here and show photos of my stock ground glass and compare it to photos of the new acrylic ground glass.

AtlantaTerry
20-Jul-2015, 22:08
Bohema Studio
Lodz, Poland

http://www.ebay.com/usr/bohemastudio?_trksid=p2047675.l2559

Items for sale: http://www.ebay.com/sch/bohemastudio/m.html?_nkw=&_armrs=1&_ipg=&_from=

Their company website: http://svedovsky.com/accessories/acrylic-focusing-screens/

AtlantaTerry
20-Jul-2015, 22:12
Perhaps it's worth time spent looking for a clear overlay material that will adhere to the acrylic yet peel off if replacement is needed for some reason? Just a thought.

Why not use the material that is sold for tablet/laptop computers to prevent scratches and other marks? It is clear, designed for the job, inexpensive and removable.

I believe my local Dollar Tree stores sell a smaller size and I know MicroCenter computer stores sell larger sizes because I saw some there last week.

AtlantaTerry
20-Jul-2015, 22:24
What I think would be cool is if someone used Corning's Gorilla Glass. :)

http://www.CorningGorillaGlass.com/

axs810
20-Jul-2015, 23:16
What I think would be cool is if someone used Corning's Gorilla Glass. :)

http://www.CorningGorillaGlass.com/

Do they sell that in 4x5 or 8x10 sizes? I'm not familiar with phone and tablet screen sizes

AtlantaTerry
21-Jul-2015, 23:20
OK, I went back to one of my local Dollar Tree stores to take a look at what they offer that might be usable to cover an acrylic ground glass to prevent scratches.

They have two offerings that are offered with either Glossy (clear) or Matte protective covers. I would assume we would want to use clear for our purposes. They have covers for either iPad Air or iPad Mini. Of course, their selling price is only US $1 + taxes.

According to Apple's website these are the dimensions of the two tablet computers in question:
iPad Air: 9.7" diagonal display | the overall dimensions are: 9.4" x 6.6" or 240mm x 169.5mm
iPad Mini: 7.9" diagonal display | the overall dimensions are: 7.87" x 5.3" or 200mm x 134.7mm

So while the iPad Air removable protective plastic cover should work with an acrylic 4x5" or 5x7" ground glass, it is not large enough for an 8x10".

Maybe something is available on fleaBay.

A crappy cell phone photo of the iPad Air Glossy version on display:
137289

Jerry Bodine
22-Jul-2015, 11:34
...They have covers for either iPad Air or iPad Mini. Of course, their selling price is only US $1 + taxes...

Yes, $1 each, but the minimum order is for a case of 24. Would allow many replacements, if ever needed.

http://www.dollartree.com/household/electronics/Tablet-Screen-Protectors-for-iPad-Air/500c548c548p358207/index.pro

Drew Wiley
22-Jul-2015, 12:04
If they're vinyl covers, they'll just smudge your GG when heat releases the plasticizers. Might as well make a break-resistant cover out of polycarbonate sheet.

Jerry Bodine
22-Jul-2015, 13:21
If they're vinyl covers, they'll just smudge your GG when heat releases the plasticizers. Might as well make a break-resistant cover out of polycarbonate sheet.

Agreed. Here's a link (http://www.tapplastics.com/product/plastics/plastic_sheets_rolls/thin_gauge_polycarbonate_sheets/541) to my favorite plastics distributor, showing a polycarbonate film .005" thickness gloss/gloss surfaces with cling characteristic; 2ft x 4ft standard availability for USD $4.65. Other thicknesses/surfaces are also available. Most sheet films are .007" thick to put it in perspective.

The above link is also the path to additional data (http://www.tapplastics.com/uploads/pdf/Rowtec_DataSheet.pdf) for this material from its manufacturer.

AtlantaTerry
22-Jul-2015, 18:02
Yes, $1 each, but the minimum order is for a case of 24. Would allow many replacements, if ever needed.

http://www.dollartree.com/household/electronics/Tablet-Screen-Protectors-for-iPad-Air/500c548c548p358207/index.pro

Goodness, no Jerry. Just PM your mailing address to me and I will mail one to you. What size?

BTW, there are seven Dollar Tree stores within ten miles of Seattle.
http://www.dollartree.com/custserv/custserv.jsp?pageName=StoreLocations

Jerry Bodine
22-Jul-2015, 18:39
Goodness, no Jerry. Just PM your mailing address to me and I will mail one to you. What size?

BTW, there are seven Dollar Tree stores within ten miles of Seattle.
http://www.dollartree.com/custserv/custserv.jsp?pageName=StoreLocations

Thanks for the offer, but I think I'll stick with the polycarb material (see post #48 regarding the risk). We put in vinyl flooring in our bathrooms and you should see the yellow stains in it under every area rug placed in there. May not be the same problems, but rather not risk it.

PCC
22-Jul-2015, 21:04
There's a local plastics store that sells online and they have AR coated acrylic that is 1/8" thick. I made a ground glass using this stuff for my Toyo View 45E last weekend but it's a bit too clear and isn't very good. Still trying to work out the kinks on that one. The AR coated stuff is available as single AR and double AR. Obviously, the single side stuff is what we need.

Tap Plastics is what to look for.

Jerry Bodine
22-Jul-2015, 21:15
The link I posted in #49 is to TAP Plastics (most if not all stores are west coast locations).

AtlantaTerry
30-Jul-2015, 01:13
What I think would be cool is if someone used Corning's Gorilla Glass. :)

http://www.CorningGorillaGlass.com/

An article I just read mentions one can purchase photographs placed on Gorilla Glass.

So... it might be possible to simply purchase some Gorilla Glass without a photo on it then grind it to create a ground glass.

http://www.masterpixonglass.com/collections/frontpage

Drew Wiley
30-Jul-2015, 08:33
You can't grind or polish any coated glass or plastic, nor tempered glass. Good luck finding it one-side coated, at least at an affordable price. Maybe someone will
have a suitable little scrap. I'd be worried about any plastic remaining truly flat, esp if it's different on one side than another. Acrylic hydrates and bows, but maybe
not enough in a small size to mess things up too much. TAP is a convenient retail source with bargain scrap bins, but not a true industrial plastics dealer. Somebody should at least try polycarbonate rather than acrylic, though you'll lose about 8% brightness. I'll stick with real glass.

axs810
1-Aug-2015, 14:45
I bought one of these Acrylic ground glass thinking it would be brighter but man was I disappointed...it's darker and coarser than my original ground glass. In my opinion fine focusing is more difficult/not that great with this acrylic ground glass as compared to normal ground glass.

Ground glass
137811


Acrylic ground glass
137812



The ebay seller was a pleasure to deal with though!

Wayne
1-Aug-2015, 15:47
been waiting for your report, thanks. Bummer for you though, but it keeps an extra c note in my pocket...

steveo
11-Aug-2015, 14:15
Mine arrived a couple of days ago. It's brighter and lighter than the bathroom window that currently doubles as my gg but I messed up and measured it 5mm too long so now need to try and trim a couple mm from each side with out making a mess of it.

AtlantaTerry
12-Aug-2015, 08:02
Mine arrived a couple of days ago. It's brighter and lighter than the bathroom window that currently doubles as my gg but I messed up and measured it 5mm too long so now need to try and trim a couple mm from each side with out making a mess of it.

Have you considered sending it back asking for them to trim it?

Or I wonder if you ask your local glass shop to cut it for you as they might have the expertise and tools to do it without scratching.

steveo
13-Aug-2015, 01:58
I did but postage to and from Poland would likely be a bit silly. There are a few framing shops near my office I wonder if they'd be able to help... Good Idea, thanks.

Michael Graves
17-Oct-2015, 17:49
I purchased one of these for my Eastman 2D I recently acquired. The old ground glass was permanently stained with something (didn't realize you could do that to glass!) and cracked. So I ordered one of these. It took about two weeks to arrive. It was nicely packaged and very well manufactured. I spent all day today out playing with my new acquisition, burning up fifteen-dollar sheets of Ektar color negative film. My observations are more based on comparing my experiences to my Toyo 810M than to the old Kodak glass, since I found that one unusable. The Bohemia polycarbonate glass does throw a brighter image than the one on my Toyo, but that one is not an original Toyo. It was an eBay replacement after I dropped a lens onto the original. I've always had a touch of coordination deficiency syndrome. As another member previously posted, however, it does have a coarser texture and that make focusing with loupe more difficult that with a conventional ground glass. With the dark cloth in place and composing the image, I liked the bright image I get with the Bohemia. But using a loupe will take some getting used to. Mine is a 7x Peak Scale. I also have a 5x Fuji. I think I'll try that the next time and see if it isn't easier to use. I think my biggest fear is how well it will hold up. I'm thinking that running the metal edges of focusing loupes across the surface on a regular basis is going to scratch it up.