In Febuary 2010, Hitech announced a line of "Neutral Density Reverse Graduated" filters. Reverse Graduated filters were originally developed by American filter manufacturer Singh Ray in association with photographer Daryl Benson. Like standard ND grad filters, the bottom half of the filter is clear, having no effect on your image and the top has a neutral density coating, reducing light transmission.

Where the two filter types differ is the graduation its self; reverse grads have a hard transition from clear to ND, but then slowly fade back to almost clear at the top.
Primarily designed for use at sunrise and sunset, when the sun if on horizon. The denser middle area of the filter holds back the super bright area on and just above the horizon, whilst the slow graduation back to a lower density at the top stops overly darkening the sky, helping to retain finer details higher in the scene.

I'd been looking into getting a reverse grad for a while but at £120 [minus shipping and tax] each from the US, I decided to wait, hoping for a British manufacturer to jump on the band wagon. Luckily, Hitech were quick off the mark and go working on their own version.

I've been using one since June 2010. Here's my thoughts and experiences with my 0.9 Hitech Reverse Grad.

Specifications

Initial Thoughts

First of all, I need to make an admission - This is my second Hitech 0.9 Reverse Grad. The first one I got was for all intensive purpose useless. I don't mean it had a small scratch or something, I mean it was terribly made and flawed beyond use.
My first example had an extremely uneven horizon, the graduation its self was uneven, and there was a bleed towards the edges, where the dye had bled through the transition into the clear part of the filter.
For a filter the price of a Lee grad, I was gutted. I had such high hopes for these Hitech reverse grads.

First thing I did was get in contact with the shop I purchase most of my filters from, Teamwork Photo, and explained the situation. Another one was dispatched that same day, hence why I'm a loyal customer...
The second filter I received was of a much higher quality; the horizon is still slightly wonky but nothing compared to the 10° shift on the original, the graduation is even and there's no bleed.
I'm hoping the original one I received was just a bunk one that slipped through.

Besides the minor gripes, the filter its self has Hitech's standard high quality. Its well constructed, a lot more neutral than a Cokin though not quite on par with Lee. Its an all round well built piece of kit.
My only concern with Hitech filters is that they're dispatched in plastic wallets, not unlike the ones CD's come in. The edges of these can be quite sharp and could easily scratch a resin filter like a Hitech. I wish they'd go with either a paper or filter pouch style wallet.
The last thing I want when getting my brand new filter out of its packaging is to have it scratched by what its meant to be protecting it.

In Practise

This type of filter is a joy to use; I adjusted to using the reverse grad really quickly. There's a clear difference between shots taken with a reverse grad and a standard grad at sunset. The fine details and subtleties in clouds towards the top of the scene come alive when using a reverse grad, thanks to its lower density towards the top.
You only really need 3 stops over the brightest area, which at sunrise/sunset is usually the horizon. Standard grads will darken down the whole sky, frequently removing any subtle colours and patterns in the higher clouds. The lower density at the top, around a stop lower, allows such fine details and colours in the clouds to be balanced against the bright horizon.
Sunsets take on a whole different appearance.

The one major problem when using a reverse grad is that anything that breaks the horizon, be it a tree, building or sign post, is going to get very dark, very quickly. Be prepared to take a second exposure without the filter so you can fill in the massively under-exposed detail later in post-production, as there's a seriously noticeable difference in exposure.

The reverse type filter is very much suited to seascapes and level horizoned landscapes.

Unfortunately, due to not being loaded, I can't get a Singh Ray reverse grad to compare the Hitech against. But for all intensive purposes, I can't really imagine there's much difference between them. At least not a 120% price elevation difference anyways.
I'm sure the Singh Ray version has got better colour neutrality but I honestly can't see the reason for the price difference.

I know I've said it a lot, but I don't think I can stress enough details and subtlety the reverse grad lets you keep in the higher extremes of the sky.
If you're into your sunsets and sunrises, I strongly urge you to try one out. I honestly think it brought a new dimension to my exposures...

Pros and Cons

Conclusion

Should you get one? If you, like myself, mostly photograph sunsets and sunrises, then yes. Definitely. Absolutely. Positively.
Just be prepared that the one you get might be rather crap. I was gutted when I got my first one, but the guys at Teamwork Photo sorted it out so well.
I hate to keep going on about it but the higher cloud detail achievable with the filter is just phenomenal...
Sunset over a seascape + reverse grad = pure, unadulterated joy.

I'd seriouslly recommend them though. I'm looking at getting another to replace my slightly scratched 0.9. I'm also looking at adding a 0.6 reverse to my arsenal too.

Absolutely adore them.

Anyways. Thats the review/my thoughts.
I hope if you're looking at getting a Hitech Reverse grad, these rambles help you come to a conclusion.
Example images at the bottom, all taken using the reverse grad.

Thanks for reading,
Matt.

Examples

All of these were taken with the Hitech 0.9 Reverse Grad.

I'm not one for messing around with colours and boosting saturation. If the colours are in the photos, its because they were present. Thats the truth, don't believe it, thats fine. :)

Oh, and I'm not sponsored by Teamwork Photo. I just love their customer services.