Hoyarex Skylight 1B filter

The Hoyarex Skylight 1B filter – cat number 011 – is one of the most valuable filters in the Hoyarex range, yet is often overlooked, because its not a special effect filter.
Hoyarex Skylight 1B filter
But this underused filter will do two things to ensure your photography improves.

Firstly, and most importantly, the filter is a lens protector. The Hoyarex system is made so that when a filter is placed in the back slot it removes any possibility of dust reaching the lens. So if the holder is left on with a filter inserted the lens wont get dust falling on the surface or scratches. The skylight is the obvious choice as it has no special effect value. It’s also one of the few filters in the Hoyarex range that’s made from glass so optically very good.
Hoyarex filter in to Holder
But the filter has another use. A skylight filter has a very slight pink tint that has a warming effect when shooting in hazy days, so landscapes can be photographed with slightly more clarity. skylight filter pink tint

Using the filter in the back slot near the lens means there still another slot free for a special effect filter when you want to add a graduated effect, sepia tone or spot for example.  Hoyarex holder screwed on lens  Photographyattic has the Hoyarex 011 Skylight 1B glass filter for sale here

Circular or Round filters?

Many new filter buyers are unsure whether to buy a round filter or one of the many square options.

system filters or round?

A round filter screws directly onto the front of your lens. A Square filter slides into a filter holder that has an adaptor ring matching the filter thread size of your lens.

There are a few advantages and disadvantages to consider.

The main advantage with a filter system, using a filter holder is that you only need one filter for a number of lenses. You just need to change the adaptor ring so the filter and holder will fit on to a different lens. Once you’ve bought the adaptor and ring system filters tend to be less expensive.
+ System Filters

This not only means it’s a lower cost when you have a selection of lenses, but you also save space. Imagine wanting five different filters and you have four lenses with different filter thread sizes. You’d need 20 filters in total! Well this is not exactly true as you can buy step up or step down rings to change the size of the lens’ filter thread.
+ System Filters

Screw in filters are often better quality. They’re usually made of glass and of the highest optical quality. Being glass they don’t scratch easily either, so are easier to clean without damage.
+ Round Filters

Screw in filters tend to take up less room as there’s no holder required. They are less protruding on a lens too so there’s less chance of vignetting (caused by the filter obstructing the corners of the frame).
+ Round Filters

The filter holder type of filter design usually means there’s a gap between the lens and the filter. This not only potentially reduces quality as light has more complicated path to follow, but also means the lens could be exposed to the elements more.
+ Round Filters

Although there are plenty of screw-in filter options you won’t get a wider range than a system filter, especially in the more creative options.
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Practicallity of use
If you intend using graduated filters you can’t beat the slot in system as you have the option to move the gradient up or down in the holder, whereas a screw in filter has the gradient fixed across the middle.
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Screw in filters stand you more chance of cross threading the filter on the lens thread. They are harder to remove if you over tighten too. While system filters need a two step process, so are slower at first while you have to attach the holder then slip the filter in. If, however you can put up with the extra bulk at the front of your lens and leave a filter holder attached the slip in type become far less fiddly.
+ System Filters  

If you decide to sell your filters square ones tend to fetch a better price on sites like ebay.
+ System Filters

There are many filters are for sale here:
Cokin A series,
Cokin P series,
Hoyarex System,
Cromatek System,
Round filters

Pro 4 Hood Guide

The Pro 4 Hood was a  unique design that allowed four effects filters to be loaded up and quickly flipped over the lens before taking a shot.

Each of the four flaps has a clip frame  to hold a Cokin A series or other 67mm square filter.

Benefit as well as speed is once the filters are in place you don’t have to handle them so they don’t get marked as easy.

The hood was popular with medium format wedding and portrait photographers, but can also be used on 35mm and digital cameras.

You can buy one here: Pro4 Hood along with various size adaptors.

Here’s a video of how the Pro 4 Hood works.