Mamiya 7 II & Filter-Factors.

Monokrome

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Does anyone use the built in meter for exposing b/w films, using colored filters with the Mamiya 7 II?
I have B+W 022 and 023 filters and I am not quite sure how to set the ISO for these filters. My films are Ilford HP5 Plus and Delta 100 with development in ID-11 1+1 if that helps.

I dont have this problem with my Leica M6 TTL. :D
 
Take a look at http://www.schneideroptics.com/info/handbook/pdf/B+WHandbook30_35.pdf

It gives a filter factor of 2 for the 022, and 3 for the 023. For the former, set the exp. comp. dial to +1 stop, and for the latter, 1 2/3 stops. You may want to bracket slightly around these values, and look at the film/prints later to determine the optimum factor for your own workflow -- filter factors are only a guide.

On a Leica M6, the exposure is taken through the lens (and therefore through the filter), so it's not necessary to do this. The meter on the Mamiya 7 is not TTL, of course.
 
I strongly advise you NOT to use the manufacturers film factors but your own.

Shoot a frame without the filter and then one with, using various filter factors. Record what is what and then look at the negs and decide what the most suitable facor is. The factor will be greater at high altitude as there is more blue light.

I had terrible problems using manufacturers factors and when I tested them I realised thats because they were MILES OUT for my use.

My tests showed a #8 yellow is best at about +1/3 stop. +2/3 gets more exposure than the control without a filter. +1/2 would likely be perfect for cameras with 1/2 stop increments but +1/3 is so close you really cannot see a difference.

M B&W Orange/Red (I forget the number, but it looks like a rich orange) turned out best at + 1 and 1/3 stops.... so both needed 2/3 stops less exposure than the manufacturer which explained why I was getting dense negs with their numbers. Now my shadow exposure is the same with or without a filter, though I do adjust to get the results I want (i.e. add more if photographing something with a crucial area in the shade under a big blue sky.

I suspect their numbers are a conservative max i.e. what you need at 10,000ft.
 
I strongly advise you NOT to use the manufacturers film factors but your own.

Shoot a frame without the filter and then one with, using various filter factors. Record what is what and then look at the negs and decide what the most suitable facor is. The factor will be greater at high altitude as there is more blue light.

I had terrible problems using manufacturers factors and when I tested them I realised thats because they were MILES OUT for my use.

My tests showed a #8 yellow is best at about +1/3 stop. +2/3 gets more exposure than the control without a filter. +1/2 would likely be perfect for cameras with 1/2 stop increments but +1/3 is so close you really cannot see a difference.

M B&W Orange/Red (I forget the number, but it looks like a rich orange) turned out best at + 1 and 1/3 stops.... so both needed 2/3 stops less exposure than the manufacturer which explained why I was getting dense negs with their numbers. Now my shadow exposure is the same with or without a filter, though I do adjust to get the results I want (i.e. add more if photographing something with a crucial area in the shade under a big blue sky.

I suspect their numbers are a conservative max i.e. what you need at 10,000ft.
Thanks dprees and Turtle. I am glad that you mentioned the factors are a guide rather than absolute.
I have just bought a Hoya X0 Yellow-Green, so I will have to find the Hoya factor for that as well.
 
The factors are NOT a guide. Use that information. The errors are in metering, not filter factors--meters have color errors, so never meter through a filter.
 
The factors are NOT a guide. Use that information. The errors are in metering, not filter factors--meters have color errors, so never meter through a filter.

This is not correct. They are a guide and entirely dependent upon the colour temperature of the light passing through them. After all, this is how they work. The manufacturer cannot possibly know the colour temperature you will be shooting under so they come up with a 'guide.' Just like metering you have to use your brain and figure out what works for you. Its best to test and use your own eyes as a judge. FWIW I know plenty of people whose results are the same as mine and I suspect every single person using TTL metering will be... read on:

The Mamiya 7 does not meter through the lens and so is not prone to any colour influences on the meter associated with a filter. Different story with TTL metering, but in my experience it has little to no impact with paler filters, but becomes a significant problem with deep reds.

Having shot hundreds of rolls with my Mamiya 7, numerous test etc I am 100% certain that with my Mamiya 7 and B&W filters, if I use the filter factors provided by B&W I will get consistently overexposed negatives compared to those without a filter. Its plain as day and it first came to my attention by virtue of my exposures being all over the place when I used filters mixed with no filters on the same rolls. I later realised that on a roll where I used no filter they were consistent. After doing extensive tests to determine my factors, and applying my own factors, I now get the colour effect (i.e. the orange deepening skies etc) without getting over exposure. My rolls are perfectly consistent from frame to frame no matter which filter I use.

If you think about it, with shadows on a blue sky day being heavily influenced by reflected blue light, were my filter factors too low (they are lower than the manufacturers) I would be getting underexposure. The truth is I am not getting underexposure in shadows, but the same as with no filter, when on a blue day you should get underexposure in the shadows as an orange or yellow filter should reduce the passage of blue light. My tests were designed to ensure that I get consistent shadow exposure under average conditions (which includes sunshine and blue skies for Afghanistan). The B&W factors clearly give significantly more shadow detail and so are over compensating even in those areas where blue light is prevalent. I suspect they would be perfect by the sea or at altitude or when there is little direct sunlight over the subject but instead the 'blue sky soft box effect.'

At the end of the day it is about what you want to achieve, but one thing I promise you, is that if you shoot a control frame with no filters and then put a #8 B&W on and add a full stop (the manufacturer's factor), that frame will show more shadow detail than the control. Try it on an overcast day and it will leap out at you!

Whats interesting is that when I put the a #8 on my ZM lenses, the Leica meter shows a need for 1/3 stop more light.... so in perfect agreement with my non-TTL tests. The Orange (I think a #23) comes out at +1 1/3 also like my tests and again, exposures are perfectly in agreement with filterless images only with deeper skies. If there is deep skylit shade that I need lots of detail in, I open up a bit more, but it takes a heck of a lot of blue to need to do this.
 
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Are you exposing for the negative or the print? Certainly a denser negative would be easier to make a good print out of.
 
Thanks dprees and Turtle. I am glad that you mentioned the factors are a guide rather than absolute.
I have just bought a Hoya X0 Yellow-Green, so I will have to find the Hoya factor for that as well.

Go shoot some scenes without the filter and then with, applying various factors. Make clear records by frame number. I would recommend the following, separately so you can see how different subjects react:

Overcast day with gray scenery. Urban environment good for this.
Bright green foliage.
Blue skies, sunny, but not severe contrast.

It might take a couple of rolls, but you will be really glad you did this.
 
This is not correct. They are a guide and entirely dependent upon the colour temperature of the light passing through them. After all, this is how they work. The manufacturer cannot possibly know the colour temperature you will be shooting under so they come up with a 'guide.' Just like metering you have to use your brain and figure out what works for you. Its best to test and use your own eyes as a judge. FWIW I know plenty of people whose results are the same as mine and I suspect every single person using TTL metering will be... read on:

The Mamiya 7 does not meter through the lens and so is not prone to any colour influences on the meter associated with a filter. Different story with TTL metering, but in my experience it has little to no impact with paler filters, but becomes a significant problem with deep reds.

Having shot hundreds of rolls with my Mamiya 7, numerous test etc I am 100% certain that with my Mamiya 7 and B&W filters, if I use the filter factors provided by B&W I will get consistently overexposed negatives compared to those without a filter. Its plain as day and it first came to my attention by virtue of my exposures being all over the place when I used filters mixed with no filters on the same rolls. I later realised that on a roll where I used no filter they were consistent. After doing extensive tests to determine my factors, and applying my own factors, I now get the colour effect (i.e. the orange deepening skies etc) without getting over exposure. My rolls are perfectly consistent from frame to frame no matter which filter I use.

If you think about it, with shadows on a blue sky day being heavily influenced by reflected blue light, were my filter factors too low (they are lower than the manufacturers) I would be getting underexposure. The truth is I am not getting underexposure in shadows, but the same as with no filter, when on a blue day you should get underexposure in the shadows as an orange or yellow filter should reduce the passage of blue light. My tests were designed to ensure that I get consistent shadow exposure under average conditions (which includes sunshine and blue skies for Afghanistan). The B&W factors clearly give significantly more shadow detail and so are over compensating even in those areas where blue light is prevalent. I suspect they would be perfect by the sea or at altitude or when there is little direct sunlight over the subject but instead the 'blue sky soft box effect.'

At the end of the day it is about what you want to achieve, but one thing I promise you, is that if you shoot a control frame with no filters and then put a #8 B&W on and add a full stop (the manufacturer's factor), that frame will show more shadow detail than the control. Try it on an overcast day and it will leap out at you!

Whats interesting is that when I put the a #8 on my ZM lenses, the Leica meter shows a need for 1/3 stop more light.... so in perfect agreement with my non-TTL tests. The Orange (I think a #23) comes out at +1 1/3 also like my tests and again, exposures are perfectly in agreement with filterless images only with deeper skies. If there is deep skylit shade that I need lots of detail in, I open up a bit more, but it takes a heck of a lot of blue to need to do this.

Actually, the factors are correct. You are just changing the parameters to match your subjective judgment and your system. These filters are designed to remove blue so the fact that you shadows deepen is not a surprise. If you want to personalize you exposures, go ahead. But since you have no idea about the tastes of others, nor the conditions they are shooting under, the only place to start is with the manufacturers filter factors.
 
Actually, the factors are correct. You are just changing the parameters to match your subjective judgment and your system. These filters are designed to remove blue so the fact that you shadows deepen is not a surprise. If you want to personalize you exposures, go ahead. But since you have no idea about the tastes of others, nor the conditions they are shooting under, the only place to start is with the manufacturers filter factors.

You have mis-read my post and gotten things in reverse. It is irrelevant whether the filter factors are 'correct' if the test criteria bear no relationship to shooting conditions. They appear not to bear any relation to mine and I shoot under big blue skies too.

The OP asked whether the manufacturers factors are always right and I said to test as I found they were miles out. You say to use the manufacturers factor because it is always right, period. You say:

Originally Posted by Finder
"The factors are NOT a guide. Use that information. The errors are in metering, not filter factors--meters have color errors, so never meter through a filter."


Sorry, this is misleading very poor advice if the intent it to help the OP get the best results. If you are not metering through the filter how can the error be due to metering?

I have tested the B&W filters asked about extensively and for every manner of test I managed (with the stated exception of extreme blue light dominance) my factors maintain shadow exposure which for B&W photography is probably the only useful benchmark. The point being that with my filter factors the shadows remain the same as the control, but with the manufacturer's figures they increase in density. Yes, you would expect a yellow or orange to deepen skylit shadows but my factors are such that even with a big blue sky and normal shooting, I get the same shadow density as the control i.e. over 99% of shooting situations that would apply not only to me but others.

Try running a test and then tell me you still disagree. I bet you would have to be half way up a large mountain under a big blue sky to need the full stop to maintain equal shadow detail on a #8 compared to no filter.
I am very confident that you will change your tune. I have run the test on various cameras, films and conditions and the results were identical.

Over exposure is overexposure. Using the manufacturers factors, if anything, blue sky values were maintained and the density of every other part of the neg increased substantially. Thats no use whatsoever as it requires printing down a very dense neg. If your shadows take a hike over the control (and assuming the control metering is as desired) what would the point in that be?

I suspect the manufacturers use a very conservative factor to ensure you do not lose excessive shadow detail when in areas heavily under blue light. This makes sense and does not mean I am making things fit my sebjective argument, only that their testing to determine factors is not representative of most shooting conditions, only an extreme that they have cautiously catered to.

Have you actually done any tests and speaking from experience here? I think there is something you are missing here: actual photography and real-world usage. If you take me at my word, what is wrong with the logic outlined above and in what way would be better to use the manufacturers factors and consistently result in over exposed negs unless I drop the exposure by 2/3 stops (which is what I am doing!)???
 
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Well, I have shot at sea level on three continents, at 3,000m in the Japanese Alps for a period of 16 years, and at 4,000 to 5,000 meters in Tibet, China. I do not agree with you. In fact, in some situations the filter factor led to underexposure. In all cases, sky density decreases.

BTW, I know folks to use a second body with TTL metering or to hold filters over spot meters to determine exposure because they believe it is easier. My warning was of a general nature, not specifically for a Mamiya 7.
 
Take a look at http://www.schneideroptics.com/info/handbook/pdf/B+WHandbook30_35.pdf

It gives a filter factor of 2 for the 022, and 3 for the 023. For the former, set the exp. comp. dial to +1 stop, and for the latter, 1 2/3 stops. You may want to bracket slightly around these values, and look at the film/prints later to determine the optimum factor for your own workflow -- filter factors are only a guide.

On a Leica M6, the exposure is taken through the lens (and therefore through the filter), so it's not necessary to do this. The meter on the Mamiya 7 is not TTL, of course.

also, if you end up using a filter with a higher filter factor like the 091, you can adjust the iso instead of using the exposure compensation dial since on the 7II, the exp comp only allows you to adjust by 2stops and the 091 requires a 3 stop compensation. works out great imo
 
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