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13

From my point of view - or how I use my gels - there are two main usage points: Adjusting a color to get a color effect. For example make your flash-light red/green/... to get a interesting background color spot. Adjusting flash color to the color of ambient light, so that your picture have only one color of light. If you have different light-colors in one ...


11

Yes, their main purpose is to have different colors on different lights. However in the vast majority of cases (if not always) you simply cannot reproduce this setup in post. The human eye is quite good at detecting natural light falloff and it will detect the things which are Photoshopped, especially if we talk about a setup with multiple lights (we ...


9

I tried hard to find a source for that information, but no luck. However, it doesn't sound right to me because the idea behind putting a gel on a flash is to alter the light to match the ambient, be it tungsten, fluorescent, etc. That activity is independent of the sensor or the film in and of itself, it's simply about making the light outputs match each ...


9

They are gels for coloring the flash. Used for creative effect or to color match the ambient lighting. CTO (color temp orange) is for matching the flash to incandescent lights or sunrise/sunset. CTB (blue) is for matching with cooler sources (cool LED's, shade, etc)... it was originally intended to shift tungsten sources to daylight so it's not used for ...


8

No. Don't try gels. Your camera should have a custom white balance setting. Something like this: You need a 3 step process for this: 1) Take a photo of a white object using either Sun White Balance or Flash White balance (I prefer using sun). You can use a sheet of paper but as they can vary in the color you probably need a professional-grade gray card ...


7

In lighting terms, a gel is a piece of thin, transparent, plasticky material in the color of your choosing. Rosco and LEE are perhaps the best known gel manufacturers, at least in the US. Gels come in large sheets that you cut down to fit your application. One 20"x24" sheet of a given color will probably last a lifetime if you're only using it in your gel ...


6

Yes. It depends upon the gel, of course. A full CTO will effect the light coming form the flash more than 1/4 CTO. Do you need to compensate for it? TTL flash will automatically measure the output coming from the flash and adjust according, so no. If you're using the flash in manual mode then yes, you will need to compensate for it.


6

If light colors don't match (or you don't want them to match and they do) then you can't correct for this in post. Lights interact with each other and there is no good way to tell which light is contributing where in a reliable and automatic manner in post. This means that you can not adjust the color characteristics of an individual light after shooting. ...


6

It will still be quite noticeable. Even at very low power a flash is hard to miss. A flash set at 1/128 power is seven stops dimmer than the same flash at full power, yet it is hard for a person to tell the difference just by observing the flash fire. This is probably due to the fact that the irises of the eyes of people in a dark location are enlarged and ...


4

Very little diffusion happens, which is why gels look clear and not cloudy, but gels absorb certain frequencies of light, so the total output is reduced. If your camera and flash support TTL metering, then the camera should compensate for the light loss however unless the camera has RGB metering it can't compensate properly and may require you dial in some ...


4

You could use a digital camera to improve accuracy of eyeballing. Set its White Balance setting to "flash WB" and take a picture of a custom WB target (a gray card, white paper, bride's dress etc), without actually using flash. Switch the camera to playback that picture, and find a gel from your pack so that the WB target, viewed through the gel, looks the ...


4

Is there a way to know which power CTO gel you need to make the shot or is that more of an artistic choice? Yes. There are ways to figure out what CTO you need, but what you need is really just a matter of what you want, so it's always going to be a matter of your choice. To figure it out, you need to know what color temperature the light you have is, and ...


4

A gel filter cut to a circle slightly larger than 39mm in diameter is what the holder is designed to hold. There should be a flap that opens up and lets you insert the filter material. You then close the flap back over the filter material to hold it in place.


3

What you seem to be looking for does not seem to exist in gel form. The type of filter you require for what you wish to do is available from Edmund Optics. They offer these filters with either a rigid plastic or flexible film substrate in both right and left hand versions. The filters with the film substrate option, while not gels, can be cut and flexed ...


3

There are colour meters, like the Sekonic C500, but they've never been cheap. Even a used Minolta will set you back a bit. And they're far more accurate than you really need; a few 10s of CC difference between ambient and flash doesn't make enough difference to warrant the trouble unless you are working on something that is truly colour-critical (like ...


3

One main reason color gels are used on flashes is to match ambient lighting so that white-balance correction doesn't become a post-processing nightmare. When you use a flash, the color temperature of the light that comes from the flash is often different from that of the ambient lighting. And the mixed sources of lighting will both hit the same subject and ...


3

Samantha: Stop watching a bunch of videos about gels and gear and whatever. Get a victim... I mean, a model, and experiment. If you can not get another person to model, learn how to use a timer on your camera and take self-portraits. What do you see on the image? The light is clearly red, so get any transparent or translucent red thing. A bag, a Coke ...


3

Those are coloured filters to put in front of the flash, simply to change the colour of the light. There is really not much more to it. In the film days, it could however make sense to e.g. use a yellow filter on the flash if you used colour film balanced for tungsten or indoor lighting. Flashes have colour temperatures similar to daylight and if using a ...


2

My guess is that the studio lights overpowered the speedlight to the point it was barely contributing to the lighting. Next time turn off all the studio lights, place the speedlight with the gel, take test photos and adjust the camera settings until you get the effect you want (or maybe just a bit darker then you want), then turn on the studio lights and ...


2

The rapid change in light level caused by the flash will be detected by rod cells in the eye. These cells are responsible for detecting movement and do no see in colour so changing the colour of the flash will not decrease the change of it being noticed.


2

Gelatin filter were and are for the most part made of Gelatin and as such are very fragile and next to imposible to clean because their so soft and absorbent, a reason why some are glass mounted. Gelatin filters will fade with time and should be replaced occasionally and stored in their original packaging. Accuracy in colored glass is very expensive and ...


2

B&H sells the Wratten 2 filters ND #96 3 and ND #96 4 in 75mm X 75mm squares. They carry the other sizes listed on the Kodak chart as well. Since searching the B&H site doesn't always find them easily, I searched for them by googling "kodak xxxxxxx" where xxxxxxx is the number listed on the Kodak chart. You can also order them directly from Kodak ...


2

Gels aren't generally available as screw-on type filters. To place a gel on the front of the lens requires a holder of some kind and a much larger quantity of the filter media. Many "sample" sets of various color gels come in sizes that allow for trimming to fit a rear filter holder but not large enough to fill a front sized filter holder. Due to the less ...


2

You can get sheets of polarizing gel filters designed to be used on studio and theatrical lighting and trim a piece to fit the rear gel holder. They're not cheap, though. The main problem would be the sheets are linear polarizers and so the auto focus system on you camera would likely be disabled. The other significant issue would be that since polarizing ...


2

Sensitivity curves of negative film are different from the permissivity curves of the filters used on digital camera sensors. For example, film was decidedly sensitive to UV light, making the use of UV filters (and also skylight filters) a good idea for certain film situations. With digital, UV filters are basically a wash and don't really cause additional ...


2

Why do SLRs and DSLRs use different flash gels? They don't. I have heard that the full CTG works well with film SLR, but something about the color sensitivity of DSLR means that they require ½CTG instead, and likewise for ½CTO. Is that correct? No it's not about the sensor vs film. Different film did however had some slight colour renditions differences,...


2

You could go the DIY route very inexpensively. In solar photography, a common solar filter is a mylar film, similar in thickness and flexibility to filter gels. Many people create their own solar filter holders. Examples to give you some ideas: $10 DIY Solar Filter for DSLR Camera The author cut up a cardboard folder into two 4" × 4" squares and a ...


2

Look at gel filter holders made by Lee. http://www.leefilters.com/index.php/camera-directory/camera-dir-list/category/gelsnap-filter-holder


2

Lee has large filter swatch samples for complete no-brainer pricing. They are actually large enough for misuse as flash filters but they should also be good for selecting what kind of sheets to acquire for good.


2

I carry a Rogue Flash Color Correction Kit that was given to me at a demo once. It's a bit pricey at $30 for a pouch, sturdy rubber band, and 3 each of: ¼, ½, and full CTO; ½ CTB; plus Green; 1 stop diffuse. But it gets the job done, and is convenient to have around. When my filters got too wrinkled and torn, I just ordered sheets of CTO and green and cut ...


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