• Ultraviolet Photography
  •  

Filter frame for unmounted 50.4mm Baader UVIR cut filter

12 replies to this topic

#1 Shane

    Member

  • Members
  • 373 posts

Posted 11 January 2019 - 20:09

Can anyone recommend a suitable filter frame that is easy to mount a Baader 50.4mm round filter in. The few I have laying around spare are either hard to unmount current filter, or not a good fit.
Thanks

#2 UlfW

    Ulf W

  • Members(+)
  • 808 posts
  • Location: Sweden, Malmö

Posted 11 January 2019 - 20:35

If you are not in a hurry and can accept the delivery-time from Aliexpress, I can recommend these filters:
https://www.aliexpre....7c914c4dSmc5tr

I have used them when experimenting with odd 50mm filter glass discs etc.

The filter cell including the retaining-ring is made of aluminium.
The retaining ring has been easy to open when replacing the filter glass.
Even the filter container is reasonably OK.

I got a second batch of these today and they had not changed the design or materials.
The inner diameter of the thread is 51.0mm and the inner diameter of the retaining-ring is 46.8mm

Edited by UlfW, 11 January 2019 - 20:40.

Ulf Wilhelmson
Curious and trying to see the invisible.

#3 OlDoinyo

    Member

  • Members(+)
  • 675 posts
  • Location: North Carolina

Posted 11 January 2019 - 22:24

Are they making them bigger these days? I mounted mine in a nominally 49mm ring. 52mm is also a standard size. If you have access to a camera shop they may have old, cheap filters around which can be cannibalized.

#4 Shane

    Member

  • Members
  • 373 posts

Posted 11 January 2019 - 23:57

Yes the camera shop option......not so accessible now that I live on an island. I was looking for the lazy way...internet, but thanks anyway.
They have been making the Baader UVIR cut filter in 50.4mm for many years.

Thanks for the dimensions Ulf, that is really useful. Some I have tried are either fractionally too tight or too big.

#5 Cadmium

    Member

  • Members(+)
  • 2,891 posts

Posted 12 January 2019 - 00:54

Digital makes some close up filters, I see them in sets usually, they don't have the ledge in the bottom, so the inside of the bottom is flat.
This is the ring I used for my Baader UVIR cut filter, which is 50.4mm diameter glass.

The Baader UV/IR-Cut/L 50.4mm glass is 3mm thick, so it needs a deeper than standard ring, especially if you want any remaining front threads for attaching other filters/hoods.
I prefer the non-ledge bottom in this situation, it provides more surface for the 50+mm glass to sit on,
most 52mm rings have a 49mm bottom ledge to accommodate the standard 49mm diameter glass used in most 52mm filters,
those standard rings are not designed to hold larger diameter glass, even though you can fit it in the upper threaded area.

On the right is the Baader UV/IR-Cut/L 50.4mm glass.
In the center is a DIGITAL brand deep ring for their +10 closeup filter in their set of 4.
https://www.amazon.c...r/dp/B001AO4UHY
https://www.ebay.com...YQAAOSwUM5Z6ME3
(sorry, those are not the correct size, you need the 52mm version)
On the left is one of the other 3 shallower filter in their set of 4, which is deeper than most standard rings, but is still not deep enough to house the 3mm glass and have remaining front threads.

Shane, if you want one of these rings, pre-labeled even (choice of many colors), I have a bunch of them that I seldom use. I will send you one free. Let me know.
Attached Image: Baader_UVIRcut_Rings.jpg

These 'DIGITAL' brand rings are not very high quality, not what I would normally use, but for this particular situation they work quite well.

Edited by Cadmium, 15 January 2019 - 14:41.


#6 Shane

    Member

  • Members
  • 373 posts

Posted 12 January 2019 - 19:43

Quote

The Baader UV/IR-Cut/L 50.4mm glass is 3mm thick, so it needs a deeper than standard ring, especially if you want any remaining front threads for attaching other filters/hoods.
Good info for the Filter sticky, if it's not already in there.

Quote

I prefer the non-ledge bottom, it provides more surface for the 50+mm glass to sit on, most 52mm rings have a 49mm bottom ledge to accommodate the standard 49mm diameter glass used in most 52mm filters,
those ring really designed are not designed to hole larger diameter glass, even though you can fit it in the upper threaded area.

Yes that's kind of what I was finding.

Quote

Shane, if you want one of these rings, pre-labeled even (choice of many colors), I have a bunch of them that I seldom use. I will send you one free. Let me know.
That would be great...I'll send you a pm in a little while. Thanks

#7 Andy Perrin

    Member

  • Members(+)
  • 2,487 posts
  • Location: United States

Posted 12 January 2019 - 20:42

What do you guys use for the 25mm filters?

#8 Cadmium

    Member

  • Members(+)
  • 2,891 posts

Posted 13 January 2019 - 06:09

Is there a 25mm version?

#9 Andy Perrin

    Member

  • Members(+)
  • 2,487 posts
  • Location: United States

Posted 13 January 2019 - 06:11

Not Baader. I mean any 25mm filters, like from Omega.

#10 Cadmium

    Member

  • Members(+)
  • 2,891 posts

Posted 13 January 2019 - 06:32

Probably 27mm or 28mm standard camera filter size. 25mm will fit inside lower ledge of most 28mm rings, but is a little loose.
Some Omega filters are fairly thick, that needs to be known first. Depth is important.
Ask Omega.

Edited by Cadmium, 13 January 2019 - 06:32.


#11 dabateman

    Da Bateman

  • Members(+)
  • 1,152 posts
  • Location: Maryland

Posted 13 January 2019 - 12:18

@ Andy,

I use these:
https://www.ebay.com...a-/351817577571

Just unmount the uv filter as its one of the few with an actual retaining ring. Sometimes you may need to gently sand down the sides of the filter glass so slides in. Alternatively if in a metal ring and slightly larger, I will use a dremel grinding wheel to grind down the threads of this filter and while still hot, pop in the glass filter with a metal ring.

If all that is a bit much you can use 25mm to 28mm step up ring and exopy the filter in place.

I found that these 25mm rings just fit in a c-mount part of this adapter:
https://www.ebay.com...d=1928589076018
So you can have the filter close to sensor and add M42 helicoid to get focusing.

#12 Andy Perrin

    Member

  • Members(+)
  • 2,487 posts
  • Location: United States

Posted 13 January 2019 - 15:38

Thanks, guys.

#13 Andrea B.

    Desert Dancer

  • Owner-Administrator
  • 7,456 posts
  • Location: USA

Posted 15 January 2019 - 18:47

Edmund Optics 52mm filter holder for unmounted 2" dia. round filters is the ideal solution and very nicely made --
although a bit pricey at (US)$50.

Do download the specs (there is a pdf format) to be sure of the maximum diameter.

Stock #83-340
https://www.edmundop...g-Lenses/26485/

I use this filter holder for my unmounted Edmund 340/10 UV-Pass.

Edmund also has a filter holder for 2" square filter glass, but I think it probably leaks light through the corners?
https://www.edmundop...g-Lenses/16210/
Andrea G. Blum
Often found hanging out with flowers & bees.