Opticallimits

Hello fellow zoners,



Have you ever heard of the Dörr products and have you had experience with them? Especially filters.



http://www.doerrfoto.de/index.aspx



I'm looking for a 10 stop Neutral density filters and the Hoya & B+W filters are out of stock in most places I checked. So I was proposed an 8 stop Dörr.



The logo looks familiar (maybe because it vaguely looks like Zeiss?) as if it's been around for quite some time but then, cokin has been too and I couldn't say I appreciated their filters very much.



Any comments are welcome, thanks in advance !



Sylvain

[quote name='Sylvain' date='05 July 2010 - 12:17 PM' timestamp='1278325054' post='828']

Hello fellow zoners,



Have you ever heard of the Dörr products and have you had experience with them? Especially filters.



http://www.doerrfoto.de/index.aspx



I'm looking for a 10 stop Neutral density filters and the Hoya & B+W filters are out of stock in most places I checked. So I was proposed an 8 stop Dörr.



The logo looks familiar (maybe because it vaguely looks like Zeiss?) as if it's been around for quite some time but then, cokin has been too and I couldn't say I appreciated their filters very much.



Any comments are welcome, thanks in advance !



Sylvain

[/quote]





Most likely rebatched Marumi filters (which by-the-way did get good scores at lenstip, see links here: http://photonius.wikispaces.com/Filters).

DHG is the coating of marumi, and if you look at doerr, they offer a "soft fantasy dhg" filter, like Marumi. Nobody else - as far as I know- labels a soft filter

as "soft fantasy".

Hi Sylvain,



I've come across Dörr products a few times - they are more of a low-price company like Hama etc. The company has existed for about 25 years.



I guess they are importing and re-labelling cheap Asian supplies, judging by the low prices for most of their product range. Thus, I wouldn't expect top quality from a Dörr filter, though if you're lucky it won't be too bad either.

[quote name='Pinhole' date='05 July 2010 - 01:05 PM' timestamp='1278331515' post='830']

Hi Sylvain,



I've come across Dörr products a few times - they are more of a low-price company like Hama etc. The company has existed for about 25 years.



I guess they are importing and re-labelling cheap Asian supplies, judging by the low prices for most of their product range. Thus, I wouldn't expect top quality from a Dörr filter, though if you're lucky it won't be too bad either.

[/quote]



Thanks Photonius, Pinhole. Good to know.

I eventually found a B+W in stock somewhere else so I went for the B+W. Actually, they were proposing an Dörr ND8 filter as an alternative which is merely 3 stops and not 10 as I was looking for!

Sylvian, I have the solemn duty to tell you the truth about ND definitions. ;-)





B+W uses ND numbers like this:

ND3 means 10 to the power of 3 (10x10x10): 1/1000 of the light is transmitted, the rest will be absorbed (and reflected). 1/1000 is (roughly) 10 stops down (2 to the power of 10 = 1024).



The others (including Marumi, Kenko, Doerr) are using quite another defininition:

ND3 means 1/3 of the light is transmitted.



Take care:

The Doerr ND8 will transmit 1/8 of the light = 3 stops down.

A B+W ND8 (not existing) would transmit 1/100,000,000 of the light ... about 26 stops down ... from f/1.0 to

f/8192 (+- a few thousands), i guess.



The question is: What are you looking for?



To stop down by 8, you will need two B+W filters ND1,8 + ND0,6 stacked. (= Type 106 + 102)

To reduce the light by factor 8 (3 stops) you need an B+W 103 or a Doerr ND8.



Confused? Don't worry, this mess is not covered in the english wikipedia nor in the german one.



Ciao, Walter



PS: I waited too long for the reply, I see you found the correct answer already.

I have the B+W Type 110. Take care, it is *not* neutral, you will get a red cast. I suggest to use a white balance card.

[quote name='Walter Schulz' date='05 July 2010 - 01:54 PM' timestamp='1278334467' post='832']

Sylvian, I have the solemn duty to tell you the truth about ND definitions. ;-)





B+W uses ND numbers like this:

ND3 means 10 to the power of 3 (10x10x10): 1/1000 of the light is transmitted, the rest will be absorbed (and reflected). 1/1000 is (roughly) 10 stops down (2 to the power of 10 = 1024).



The others (including Marumi, Kenko, Doerr) are using quite another defininition:

ND3 means 1/3 of the light is transmitted.



Take care:

The Doerr ND8 will transmit 1/8 of the light = 3 stops down.

A B+W ND8 (not existing) would transmit 1/100,000,000 of the light ... about 26 stops down ... from f/1.0 to

f/8192 (+- a few thousands), i guess.



The question is: What are you looking for?



To stop down by 8, you will need two B+W filters ND1,8 + ND0,6 stacked. (= Type 106 + 102)

To reduce the light by factor 8 (3 stops) you need an B+W 103 or a Doerr ND8.



Confused? Don't worry, this mess is not covered in the english wikipedia nor in the german one.



Ciao, Walter



PS: I waited too long for the reply, I see you found the correct answer already.

I have the B+W Type 110. Take care, it is *not* neutral, you will get a red cast. I suggest to use a white balance card.

[/quote]



Ho Walter, very kind of you.

As confused as I may have looked, I was well aware of these differences in mfr. definitions <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/smile.gif' class='bbc_emoticon' alt='' />. The shop just oddly proposed me a ND8 Dorr while I was actually looking for 10 stops reduction and for a second I just thought they said stops. Surely, if you don't pay attention, and as you mentionned indeed, you can mix 8 times with stops.



I ordered a B+W ND110. I was aware of the red cast but haven't thought much about it yet. I thought I'd see in field conditions. I have a white balance card but I was somehow thinking that it wouldn't actually correct for such a cast. My very early thinking was that it was filtering other colors much more than the reds, which in my intuition was slightly different than the light temperature-induced color cast. Maybe I'm missing something here?



Thanks in advance for any clarification !

Data sheet for B+W ND filters:

http://foto-huppert.de/prdimages/bwc17.pdf

German languange only, but the transmission curves are speaking for themselves.

In the beginning I got very strange results. But most of the damage was done by DxO 4.x. The old engine added red cast by itself and - using the default settings - some neutral stones were transformed to spitting images (sic!) of things found in the Gorges du Daluis.

http://upload.wikimedia.org/wikipedia/co...var_01.jpg



Ciao, Walter

[quote name='Sylvain' timestamp='1278338527' post='833']

Ho Walter, very kind of you.

As confused as I may have looked, I was well aware of these differences in mfr. definitions <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/smile.gif' class='bbc_emoticon' alt='' />. The shop just oddly proposed me a ND8 Dorr while I was actually looking for 10 stops reduction and for a second I just thought they said stops. Surely, if you don't pay attention, and as you mentionned indeed, you can mix 8 times with stops.



I ordered a B+W ND110. I was aware of the red cast but haven't thought much about it yet. I thought I'd see in field conditions. I have a white balance card but I was somehow thinking that it wouldn't actually correct for such a cast. My very early thinking was that it was filtering other colors much more than the reds, which in my intuition was slightly different than the light temperature-induced color cast. Maybe I'm missing something here?



Thanks in advance for any clarification !

[/quote]





Right, you have to be careful. as the curves show, these filters don't absorbe so well in the red, infrared range, so you get partial infrared results, more difficult to correct.

I have only purchased one Dörr product and it was completely unintentional. I ordered a Lenspen Sensorklear sensor cleaning pen. When I opened the box and saw a Dörr Sensor Klear package I was disappointed until I actually looked at the pen through the clear plastic. It is a Lenspen product packaged in the Dörr packaging. The pen itself has Lenspen printed on it and not Dörr. So, I imagine that other Dörr products are repackaged items from other manufacturers. I would inspect the Dörr filter to see if it has any manufacturer's info on it before making a decision on it.