B+W 10 Stop is really an 11 stop?

stormcrow

stormcrow

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Dale
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I've had my B+W 10 stop filter for quiet a while but I've never got round to using it.
Anyway I'm planning on trying it out this weekend so I had a little play indoors with it mainly to remind myself of how the bulb function works. As a result of a few totally unscientific tests it appears that I'm having to add approx 11 1/3 stops instead of 10 stops.
Is this normal or should these filters be dead on 10 stops?
I should add I'm not worried about this as I think as long as I know roughly what to add then I can make adjustments to suit the image. I'm really just curious if this is normal?
 
tbh I have never check my ND to how many stops I change on settings, I normal just go with what ever is needed at the time.

I am assuming it will still depend on your other settings and also the light available etc.
 
stormcrow said:
I've had my B+W 10 stop filter for quiet a while but I've never got round to using it.
Anyway I'm planning on trying it out this weekend so I had a little play indoors with it mainly to remind myself of how the bulb function works. As a result of a few totally unscientific tests it appears that I'm having to add approx 11 1/3 stops instead of 10 stops.
Is this normal or should these filters be dead on 10 stops?
I should add I'm not worried about this as I think as long as I know roughly what to add then I can make adjustments to suit the image. I'm really just curious if this is normal?
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I've got no idea if it's normal but I only ever do that sort of calculation for a rough guess at exposure - chimping the lcd screen is the way forward!
 
I have only used my ND a couple of times so far but I have just used aperture mode and let the camera calculate the shutter speed then looked at the histogram then the other time used manual and started with the shutter speed it suggested and played again.
 
As I said I'm not really concerned as everone says you make adjustments to get the shot you want. I'm just a little surprised that it is not closer to being actually 10 stops after all they cost enough.
Another quick question comes to mind regarding using a 10 stop has anyone tried to use an expodisc with a 10 stop, is that even possible? should I forget about getting the white balance correct when I take the photo and just correct my raw file?
 
I would do as much as you can to get it right in the camera at the time of taking.....it doesn't take much extra effort and is far better than sitting in front of a computer trying to right wrongs.:thumbs:

Think if you were shooting on film, you would do your utmost to get it rigt because you couldn't change the result...so why do any different simply because gelatine has been changed for silicon? Seems irrational to me.

I expect you will get to know your filter and how it behaves in different circumstances before too long - just use the exposure calculations as a guide and then do your little tweak for your camera/lens/filter and the scene as required.

As a tip, I have the exposure calculator written on the back of the foam in the plastic filter box to refer to! I took the foam out and wrote down the 10 stop difference from 1/1000 downwards as a table using a permeneant felt tip. The foam was put back in the filter box and I can read the exposure difference through the box! Easy - You always have the box with you if you have the filter.:thumbs:
 
stormcrow said:
As I said I'm not really concerned as everone says you make adjustments to get the shot you want. I'm just a little surprised that it is not closer to being actually 10 stops after all they cost enough.
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If I trust to Matrix then certainly on a D700 I'd end up with underexposed shots.

I used to find that in strong daylight f/11 for around 18 to 20seconds usually did the goods, so I just generally did a quick test shot and dialed in and around that.

This is probably more of a metering issue rather than the B&W being slower than advertised.
 
Assuming my maths is correct then the difference between 10 stops and 11 stops is only 0.049% of the available light....simplistically speaking.
To manufacture within such a tolerance is a pretty remarkable achievement for the price.

Bob
 
is there a table that i can print of and have in my bag to calculate exposures.

i.e. if normal exposure is x i can just use the table and it will tell me in seconds how long 10 stop exposure would be for those conditions.
 
Canon Bob said:
Assuming my maths is correct then the difference between 10 stops and 11 stops is only 0.049% of the available light....simplistically speaking.
To manufacture within such a tolerance is a pretty remarkable achievement for the price.

Bob
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I agree with Bob. My B+W ten stopper is about 10.5 stops as best I can tell. While talking to the Lee filter guys at Focus, they said their new ten stopper also varied a bit. For the same manufacturing reasons, I would not be at all surprised if the colour varied very slightly from batch to batch.

Either way, it doesn't matter if you meter each shot individually by chimping - something you could never do with film. Given the unpredictability of film due to reciprocity failure at long exposures, using filters like this was just impossible in practise. It's pretty much a new technique to digital, without a lot of complex and unpredictable exposure calculations.

The Expodisc should work for white balance. I find doing a custom balance in the field is a bit of a pain with these things, so I have a couple of custom white balance images (sun and shade) that I don't delete off the card, so they are always there for a quick custom balance reference.
 
right now - where is the cheapest place to get one of these filters. any 10 stoip filter with good IQ, if there is an alternative to getting a B+W filter (not welding glass)
 
33L said:
right now - where is the cheapest place to get one of these filters. any 10 stoip filter with good IQ, if there is an alternative to getting a B+W filter (not welding glass)
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£75 in 77mm here http://www.fotosense.co.uk/catalogsearch/result/?q=b+w+77mm+110&x=18&y=14

There are a few alternatives around now. Two promising ones from www.Premier-Ink.co.uk - the LCW Fader ND, and also a LCW nine stops coated glass jobby that looks rather good, and cheaper - 77mm only. But both are out of stock at the moment, call for availability. Both are brand new and untested in their latest incarnations - I'm waiting for a Fader.

Hoya also make a coated glass nine stops X400, but it's expensive and special order only.

If you have a square system, the Lee Big Stopper is good.
 
Not sure - I just got a lightcraft fader nd for about £35 though (52mm size) - which goes from 2-8 stops with adjustment via a dial. Not had a chance to test it properly but it seems like a really handy bit of kit and less of a orangey cast than the B+W 10 stop I also have.

edit: got my lightcraft fader nd off ebay
 
was looking at ordering one today for del tomorrow, can throw that outta window with the bank hol weekend.
 
33L said:
is there a table that i can print of and have in my bag to calculate exposures.

i.e. if normal exposure is x i can just use the table and it will tell me in seconds how long 10 stop exposure would be for those conditions.
Click to expand...

I've got one I did, it was initially in 1 stop increments but I've now done it for 1/3 stops as that is how I have my camera setup. Its quite a comprehensive table as I have it from 1 stop to 12 stops. I dont know how I could post it here but if anyone wants it just pm me their e-mail and I will send it to you. I've uploaded 2 jpgs of the table so you can get them if you don't want the doc.
Hopefully I've got my sums correct my excuse if its wrong is I did it in my head and its a long time since I did maths at school. :)

http://img213.imageshack.us/img213/9885/99404882.jpg

http://img401.imageshack.us/img401/5836/10947250.jpg
 
stormcrow said:
I've got one I did, it was initially in 1 stop increments but I've now done it for 1/3 stops as that is how I have my camera setup. Its quite a comprehensive table as I have it from 1 stop to 12 stops. I dont know how I could post it here but if anyone wants it just pm me their e-mail and I will send it to you. I've uploaded 2 jpgs of the table so you can get them if you don't want the doc.
Hopefully I've got my sums correct my excuse if its wrong is I did it in my head and its a long time since I did maths at school. :)

http://img213.imageshack.us/img213/9885/99404882.jpg

http://img401.imageshack.us/img401/5836/10947250.jpg
Click to expand...

That's brilliantly useful, and very comprehensive :thumbs:

I defy anybody to do third-stops in their head, or even using all their fingers.
 
33L said:
What stops does that range from? i could see much info on the item, not sure on any antireflective coating either.
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I think it's 2-8 stops, same as the LCW Fader.

It looks identical to the LCW but speaking to Premier-Ink (linked earlier) they say it is not and that the new version they have coming in a week or two has different, better quality glass. LCW one is cheaper too.

When I spoke to them, they were unsure whether it was going to be coated or not - the current one isn't, so I'm assuming the Genus one isn't either.
 
HoppyUK said:
That's a handy little table, except that it's a stop out! Those figures are correct for an 11-stop filter.
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Scotty B said:
True but it puts you in the ball park of where you need to be.
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What I usually do, I bracket the shot ±0.7, and ±1.7 to give me a total of 5 shots.


As for white balance, I set it with an Expodisc prior to setting the ND, then shoot; there will be a slight colour change, sometimes giving a very pleasant effect, if not go back and re-shoot adjusting the WB temperature.
 
HoppyUK said:
I think it's 2-8 stops, same as the LCW Fader.

It looks identical to the LCW but speaking to Premier-Ink (linked earlier) they say it is not and that the new version they have coming in a week or two has different, better quality glass. LCW one is cheaper too.

When I spoke to them, they were unsure whether it was going to be coated or not - the current one isn't, so I'm assuming the Genus one isn't either.
Click to expand...

cheers Hoppy, I can see how useful a fader would be. Just not sure on the quality for the cost involved. we are not takling £10-£20. What will the new one be called?
 
33L said:
cheers Hoppy, I can see how useful a fader would be. Just not sure on the quality for the cost involved. we are not takling £10-£20. What will the new one be called?
Click to expand...

There's more on this thread http://www.talkphotography.co.uk/forums/showthread.php?t=209398&page=2

I'm thinking that LCW have maybe got the pick of the bunch here, with both the fader and also the fixed, multi-coated 9-stopper jobbie, both at a good price.

I've tried the fader at the Focus show, and liked it enough to buy one. The new version is supposed to be even better, which is what I'm waiting for. I'll post more when I get hold of it, within a couple of weeks max I'm told.
 
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