This 165 x 165mm Hitech Firecrest ND Filter for Solar Photography 7-Stopis a solid neutral density filter providing a 7-stop reduction in exposure. This 2.1 density creates a darkening of the entire image, allowing you to photograph with a wider aperture or longer shutter speed than normally required. By slowing your exposure time or increasing your aperture, you are able to control depth of field and convey movement more easily.

The design of this filter has been optimized for use with digital sensors and promote nearly flat attenuation of visible, UV, and infrared light. Due to imaging sensors' greater susceptibility to infrared light, compared to traditional film, color casts can occur when photographing darker subjects that require increased exposure times. This filter provides a high level of neutrality across all three spectrums in order to eliminate color casts and ensure cleaner, truer blacks.

Applied to the outside of the SCHOTT Superwite glass construction is a 15-layer Firecrest multicoating, which helps to minimize reflections and flare in order maintain truer colors and contrast. The multicoating is also scratch resistant and hydrophobic to benefit the overall durability of the filter. It measures 6.5 x 6.5" / 165 x 165mm and is 0.08" / 2mm-thick, making it compatible with the Lucroit 165mm Filter Holder.

This filter is designed specifically for photography applications. This filter is not suitable for direct solar viewing with the naked eye, including with optical viewfinders.

2.1 Optical Density    15-Layer Coating on Outside of Filter    Hydrophobic and Scratch Resistant    2mm-Thick SCHOTT Superwite Glass    Increase Exposure Length    Greater Control Over Exposures    Neutral Results Across All Spectrums    Fits Lucroit 165mm Filter Holder    Includes Pouch

ND 2.1 filter darkens the image, allowing you to photograph with a longer shutter speed or wider aperture than normally required.

Providing a 7 stop exposure reduction, this filter allows you to control depth of field and convey movement more easily.

Attenuates infrared light, as well as visible and UV wavelengths, to maintain color neutrality and suppress color casts due to increased exposure lengths.

The 15-layer Firecrest coating has been applied directly to the outside of the filter glass by way of a vacuum-formed, hard-coated, electrolytic process. The multicoating is water and scratch resistant for greater overall durability.

SCHOTT Superwite glass promotes maintained image clarity and its 2mm-thick design is compatible with the Lucroit 165mm Filter Holder.

Related Questions and Answers

Q: 1. Are the filters stackable?

A: It is stackable. It does have 77 mm front filter thread.

Q: 2. Is this filter suitable for solar imaging?

A: Yes, when shooting in live view, you can use it. I wouldn't use it while looking through the viewfinder if you have a DSLR but live view is ok.

Q: 3. Does this filter come in a case?

A: No it doesnt!I boughta href= http://www.bhphotovideo.com/c/product/212303-REG/B_W_65024717_E1_Filter_Pouch.html target= _blank http://www.bhphotovideo.com/c/product/212303-REG/B_W_65024717_E1_Filter_Pouch.html/aAnd its suitable.Mika from Finland

Q: 4. I have both ND 1.8 and 3.0. I found they are so different in coating. Both sides of ND 3.0 are the same. Surface of ND 3.0 like a blue mirror. I can see myself clearly in it. One side of ND 1.8 like a normal mirror with very low reflection. Another side of ND 1.8 have variant color looked in different direction. Both NDs are purchased in B&H. The 1.8 one is used. I'm not sure whether they are all right. Can you confirm this? Thank you.

A: I have both ND 1.8 and 0.9. Both sides of ND 1.8 and 0.9 are the sameSurface of ND 1.8 and 0.9 like a blue

Q: 5. What is the weight of this filter?

A: I dont know.

Q: 6. Is this filter a discontinued model? Nobody else has it at this price.

A: As far as I know it is not however, due to the Eclipse event this year, it took about 3 months to arrive. Well worth the wait though, I love it. I have 2 of these, one is a 13 stop and the other is a 16 stop filter. Both top notch quality and you can't beat the price on this site.

Q: 7. is this the same as firecrest irnd filter? I have firecrest irnd filter now and is looking for another one.

A: This filter is an IRND filter from the Firecrest Series.

Q: 8. How's the vignetting when shooting wide open? Do you have to crop any?

A: I use the the filter ONLY on my Canon 24mm TS-E... and I have not had any issues on any of my images from using this filter. As the old saying goes... you get what you pay for... so, if you're using sub-par glass using an expensive filter, EXPECT sub-par results... no matter the type of filter you use!

Q: 9. Will this work with the smallrig Lightweight Matte Box? I see many people saying 100x100mm are incompatible but they say 4x4 inch are... confusing or what??

A: The Formatt Hitech 100 x 100mm Firecrest Ultra ND 0.9 Filter (3-Stop) is incompatible with the SmallRig Lightweight Carbon Fiber Matte Box because the filter trays on the matte box support 4mm thick filters, and the Formatt Hitech filter is 2mm thick.

Q: 10. Is this filter rated as a solar filter suitable for photographing the sun?

A: Formatt Hitech 105mm Firecrest Ultra ND 5.4 Filter (18-Stop) does not have an ISO rating for safe solar viewing. It may work for a camera as it is not sensitive as human eyes, but if you want to be 100% safe I would recommend looking for a filter that is listed with an ISO rating for safe solar viewing.