Schott DUG11X and Baader-U comparison

[Cadmium]

Alternatively this may be more available:

http://www.uqgoptics...R%20BLOCKER.pdf

[Andy Perrin]

John,

 

Do you have any images you'd like to show using the the Ø25mm X 3mm 330WB70?

I found and ordered this filter recently.

It is on its way and I wonder if it is usable for photo, compared to my Baader U.

I have plenty posted here on UVP already! Just search for the filter. It's quite useable, especially if you rear mount the filter to avoid some of the angular artifacts from dichroic filters.

 

See the 2nd photo here:

http://www.ultravioletphotography.com/content/index.php/topic/1777-all-around-the-town-of-brighton-massachusetts-us/page__view__findpost__p__12144

[Cadmium]

Here are some price examples from ITOS, they have the 12mm DUG11X in stock.

1) 12mm DUG11X (in stock) unit price = € 152.80.

2) UG11-IRBII 49mm diameter x 2mm thick = EURO 501.80 (49mm fits 52mm rings).

[JMC]

Cadmium, thanks for looking in to this. I also reached out to Itos, as I saw they mentioned DUG11x on their website. They told me they didn't have any but recommended the UG11 IRB (not sure they put the 'II' on the end of it). There is a company in the UK (UQG Optics), who I also contacted about the DUG11x, as they had something on their website about it. They said they didn't have any, but they do mention about the UG11 IRB, for similar prices that you saw with Itos. However they did not fill me with confidence, as I asked whether they had the ability to measure transmission and compare it with the Baader U, all I got back was 'we cannot do custom work'. Hmmm, not quite what I expected. I came across a British museum article online which mentioned the DUG11x being used as a camera filter, so I dropped that person an email to, to see if I can go into the museum and do some test shots with it and the Baader U and see how they compare. If I hear back I'll let everyone know. To be honest I'll like a filter size to use on a lens rather than a small one, but 500 euro is not something I'd want to jump at without getting some comparisons.

 

Apologies, I cannot give this the thought it needs at the moment (family issues), but I will hopefully be back online properly in a few days.

[Cadmium]

Understood...

 

ITOS definitely has DUG11X in 12mm circles in stock. Testable size, but personally not something I would want to use for photography.

UG11-IRB(II) is a material that I was not aware of before. It is 2mm thick.

DUG11X seems to be something that needs to be cut and fabricated by Schott directly, where as the UG11-IRB(II) seems to be something they can cut/fabricate without having that done by Schott.

The linear graphs they show for UG11-IRB(II) look goods to me, but I want to see a diabatic graph version, which they are going to make for me.

However, as you say, the price...

[Andrea B.]

I was also looking at UQG website. The mention of hard coating on their DUG11X gives me pause. Sometimes that produces a shiny mirrored effect which might make its use impossible for reflected UV photography. Be sure you ask about that before buying.

 

[Cadmium]

Why does it give you pause?

It gives me no more pause than a Badder U does. Even a simple AR coating is a hard coating.

Isn't the Baader U as mirrored as anything you have ever seen?!

I am not saying it works as well as a Baader U...

I will say it is more expensive than a Baader U. :-)

 

At this point I am more interested in the UG11-IRB(II), simply because it looks like it may have an even better transmission profile, but probably about the same as DUG11(X), wait and see I guess.

It doesn't need to be fabricated directly by Schott. It is thicker, 2mm,

but it costs just as much as DUG11(X), so it is still not as affordable as the Baader U.

 

Since most lenses will not realize anything more from the deeper transmission, I see very little reason for almost anyone to spend that kind of money for something that will just cut off a lot of higher UV and give them lower UV which they can not really use.

[JMC]

You've hit the nail on the head here Cadmium. When I was looking at the curves, I saw the deeper UV transmission, and purely thinking about my UAT lens. For anyone not using specialised optics, this deeper transmission would be wasted. I'm wondering now whether the UG11 IRB is the new version of DUG11x?

[Andrea B.]

Isn't the Baader U as mirrored as anything you have ever seen?!

 

Actually, no. I have this $600 unuseable Edmund 340/10 with both sides hard-coated and mirror-like. By comparison the BaaderU is simply "very shiny". And I have a few really old hard-coated filters which are also unuseable. So the question becomes when is a shiny or mirror-like coating OK and when is it unuseable?

I don't have an answer for you on that!! :D

[Cadmium]

... And I have a few really old hard-coated filters which are also unuseable. So the question becomes when is a shiny or mirror-like coating OK and when is it unuseable?...

 

In what way are those 'unusable' ?

[Andrea B.]

Cannot make a flareless foto with some of my mirrored filters (like the Edmund 340/10)

I get rings and flare washout with any lens

 

Tried lens hood

Does not help

[JMC]

I came across a British museum article online which mentioned the DUG11x being used as a camera filter, so I dropped that person an email to, to see if I can go into the museum and do some test shots with it and the Baader U and see how they compare. If I hear back I'll let everyone know.

 

Just a quick update. I heard back from the person at the British Museum. She's out until the 13th September, but was open to me visiting to take a look at it and said to get back in touch after that, so hopefully I'll be able to go and compare it with my Baader U. Once done I'll feed back.