Filter holders

Just a quick question.

Do the Canon and Sigma 15mm Fisheye lenses have filter slots/holders on the back? And if so what size filters do they fit?

Alex

The Sigma 15mm FE does. It's about 2 x 2 cm.

Canon too, about the same size

stu

Does anybody had used filters with Canon/Sigma 15mm FE underwater ? if yes, please post the examples !

Regards

I used Craig Jones' filter scheme when I had my D100 and the Nikon mount Sigma 15mm FE lens. I hadn't liked the cyan cast to blue water that I was getting out of the D100 originally so I tried his scheme of a magenta filter on the lens and green filters on the strobes. These examples are nowhere near the caliber of Alex's filter examples, but below are a few. I'm planning to use the 15mm with my D2X, but I am optimistic that I won't need the same filter scheme to get nice blue water. However, I may want to experiment with some filters for contrast effects such as Alex has just done .

These images have had no color correction. I was pretty happy with the blue when using the filters.

Beautiful shots!

But here is a stvupid beginner question. Why would you use a filter for this composition?

The successful filter shots I have seen using filters on the strobes and lens involve CFWA with some close up subject matter strobe lit (like a fish or coral head) and some distant huge subject (like a wreck). The idea is to get both color balanced correctly.

In this case I would think you probably could have lit the entire scene with your strobes (depending upon the strobe). Was this the intent or was there some other reson for using this technique?

Beautiful shots!

 

But here is a stvupid beginner question. Why would you use a filter for this composition?

Thanks! The magenta filter was to counter the cyan cast of the blue water that I was getting with the D100. My blue water backgrounds all had a slight greenish/cyanish tint to them originally. The magenta gave me more of a sapphire (okay, Fuji) blue. The green filters on the strobes were to counter the effects of the magenta filter for the strobe lit foreground.

In fact, if you look at the bottom shot, the water still looks a tiny bit cyan, because I was using a weaker filters than the top two.

The magenta filter also helped with diminishing blowout on sunballs as I tested in the bottom shot. Craig Jones has some posts from way back about this if you search for them.

Great shots Linda !

Thanks for share your experience with us.

Regards

Thanks for the tip!

Good suggestion about the sunballs. I know that Alex has shown that high shutter speeds help with sunballs--the trouble is that you sacrifice the water color. Both techniques seem to accomplish the same thing when you think about it--reduce the overall exposure while compensating in the foreground with flash. In Alex's demonstrations you do this with shutter speed. In your case you do it with a filter by knocking the overall exposure down a stop or two, but bring up the foreground with the flash--compensating in the foreground with flash of the right color to cancel the effect of the filter. Good idea.

I wasn't aware of this problem with the d100. I'm a bit confused though. Was the D100 giving a cyan cast to everything? Is this a charcteristic of the sensor or just the way you want the blues to look? (BTW the blues look fantastic) If it is the latter then it makes sense to add the strobe filters for the foreground, but wouldn't you get a magenta hue to the sunball? Did you compensate for this in photoshop?

I've heard of using split ND filters for sunballs (but very hard to use UW). I hadn't considered using plain ND filters to get good sunballs. Perhaps this technique also improves water color with the slight drawback of needing to adjust the color around the sunball (which is much more localized and easier than adjusting just the blue water).

Thanks

I know that Alex has shown that high shutter speeds help with sunballs--the trouble is that you sacrifice the water color.

<{POST_SNAPBACK}>

Just so I'm not taking credit where its not due - it was people here on Wetpixel like Rand and Herbko who showed me the way with fast shutter speeds for sunbursts.

I will take some credit for posting some of the first shutter speed comparsion shots - but it wasn't my idea.

Here is a set from Egypt. F14 @ 1/60th, 1/125th and 1/250th. ISO 100.

Alex