AVS Forum banner

Status
Not open for further replies.
1 - 4 of 4 Posts

·
Registered
Joined
·
475 Posts
Discussion Starter · #1 ·
I've spent more time working with the 5500 and the first thing I want to do is quell and untrue rumor. It's been rumored that the lens has a 58 mm thread to accept attachments. Wrong! A 58 mm lens sits inside of the existing ring and does NOT contact the threads. Actual threads are probably 59 or maybe 60 mm. That said...


I decided to try some filters to remove blue from the true reds. My blacks (dark blues) are dark enough for our tastes and its the blue in red objects (e.g., red lipstick, etc.) that drives my crazy. I went to the local camera store and told them that I wanted an orange filter to remove blue. Of course they said that yellow removes blue. (I still can't for the life of me understand why they don't use orange as it IS complementary to blue.) Anyway we went though what they had in stock (not much) and sure enough he came up with a peach-colored filter. He also came up with a yellow filter. The peach filter is a Tiffen 85B. The intended use is "Converts Type B film to daylight." It has a recommended f-stop increase of 2/3. The yellow filter is a Tiffen 15 "Deep Yellow." This filter is intended to render dark skys for black and white film.


We first tried the 85B. Yes! It does a beautiful job of removing the blues in the red and making the blacks, well, black. Of course use of the filters required me to do far more experimentation in the menu system, and I believe that I pretty much understand the beast now. The filter required MAJOR changes in the drive levels, subbright, and subcontrast, as well as the grey scale. Ultimately, the picture had a much warmer (redder) tone. In fact, no amount of adjustment could produce a bluish-white. However, light was diminished and my wife said that she could live with the blue more than the dimness (and lack of bright whites). My wife likened it to watching through a haze. If you have a light controlled room (we don't) and prefer a warm picture, maybe this could work for you.


Without changing the settings, we tried the yellow 15. Way too yellow and there is not enough correction in the world for this filter.


At this point I was looking through the included Tiffen brochures looking for ideas... hmmmm.


Daylight filters are used to reduce overly blue skys and add contrast. I have a 58mm Vivitar Skylight 1A so I slapped it on the projector. Light loss was extremely minimal (less loss than going from regular to whisper). Well the lips still had their bluishness, but the black (dark blue) was certainly blacker and even the wife had no problem differentiating the two. It also seems to add to the contrast slightly.


These are what I've tried so far. But there are far more filters out there that bare trying. Tiffen makes several gradations to remove excess blue and haze from skys and water. They also make several (the 80-series) for correction between different film types/temperatures. Additionally, FLB and FLD filters are used to remove the blues associated with fluorescent lighting. Finally, the 85C "Helps prevent overexposure of blue record layer" and only has an f-stop increase of 1/3.


BTW, related to my work with the filters, and search for greater contrast, I constructed a photo-detection devise that uses a photocell connected to an ohm-meter. With a high-intensity light at a distace of 8", the meter read 328 ohms. The Vivitar skylight increased the resistance to 353 ohms. the 15 and 85B read 466 and 465 ohms, respectively (though Tiffen notes a 1-2/3 f-stop increase for the 15 and 2/3 for the 85B. With my hand over the cell, the resistance was 110,000 ohms.


As noted, I been delving into the workings of the beast and can now differentiate the three dark end bars, though they show little difference. I also found that if one wants to warm up their color (lower the kelvin), it is fairly easy to do using the subbright, subcontrast, and greyscale adjustments. This does not reduce the blue "leakage" though.


Do not be afraid to experiment. Write down all settings before you begin and tweak away to your hearts desire. Maybe you'll be the one to find that perfect filter/setup. If you do, let us all know.
 

·
Registered
Joined
·
1,645 Posts
Toddalin


(I still can't for the life of me understand why they don't use orange as it IS complementary to blue.)


It is not like you have a choice primary colors are Red Green Blue (AKA additive colors)


Secondary colors are Yellow Magenta Cyan (AKA subtractive colors)


This only applies to light for pigments a different rule
 

·
Registered
Joined
·
327 Posts
toddalin,

Thanks for that useful bit of information regarding filter size. So what's the neatest solution? I don't believe 59 or 60mm threads are standard sizes. I'm currently using 3"x3" and 4"x4" optical grade polyester (or gelatin) filters from Lee. They cost about US$12 each. I make my own holder to slip over the lens surround and trim the corners off the filter squares. I had the intention of getting a sturdier glass filter after deciding what type of filter works best.
 

·
Registered
Joined
·
475 Posts
Discussion Starter · #4 ·
If 59-60mm are not available, the 58 will work. It just sits inside the ring AGAINST THE GLASS. Unless you project a wide setting, you are probably not using the very edge of the lens anyway. The filter will stay in place unless you have a very severe downslope-angle.


No way would my wife ever let me slap something over the end of the lens (long-term) for aesthetic reasons.
 
1 - 4 of 4 Posts
Status
Not open for further replies.
Top