Formatt Hitech Prostop IRND 7 Stop
I recently picked up this filter incredibly cheap as it is now discontinued for the more neutral Firecrest version that Hitech sell. Whilst I would love the best neutrality for my filters being able to get a 7 stop ND filter for £40 was a bargain I couldn’t pass up. I own the Hitech 100mm holder, 3 stop hard grad and a 105 mm polarizer so I have had great experiences so far with the system and it has saved me a fair amount of money over a dedicated Lee system (although I wouldn’t complain at one!)
Why 7 stops?
I realise 7 stops is quite a random filtration amount but when budget is an issue and 7 stops saves you nearly £100 over the nearest good quality contender you learn to make do. However, 7 stops is a very significant amount and as I found in my 1 little test shot a 1/2s metered exposure quickly became minutes – and that was shooting digitally! So I realised at that point I most likely don’t need 10 stops and 7 will do just fine.
How is it?
On my initial outing I had some issues and it turns out they were completely user related because I got too excited and didn’t read their suggestions. I’ll address them here and hopefully it will save people some disappointing shoots.
1. Always place the filter closest to the lens.
This is something I didn’t take heed of initially and then when I returned home I was shocked to see pictures that were glaringly purple, lacked contrast and were much darker than what I metered. At first I assumed the filter was a bit of a poor example and just simply had an incorrectable colour cast and just generally destroyed the raw files. However, upon returning home and reading a little further I realised that in fact this was simply the filter reflecting back onto the lens. This made sense as it is incredibly dark for a filter and as I was using an ND Grad inbetween as well I was always asking for reflections.
2. Use the foam seal.
This is another I assumed was a bit of a gimmick as it was suggested to prevent light leaks but it seemed to really strengthen my results when it was attached.
3. Set up a custom white balance profile.
I’ve never done one of these before as I often use auto white balance and use the colour picker in lightroom to correct any inaccuracies. To set this I shot a grey card I have with the filter attached. This gave me a great point of reference for setting later although I knew there would be some slight variances depending on the light I was shooting in. I did find that it cooled images quite significantly so most corrections required a level of warming to get back to neutral but I strangely found that it needed quite a heavy correction towards the magenta end of the scale. I’m not sure whether this was just the particular light I was shooting in but it was quite consistent. I didn’t feel the colour correction was overly bad considering the strength of the filter, it seemed what would most likely be in line with many other high strength ND filters.
I only have a couple of finished shots with this filter as I’ve only had chance to go out with it once but I can see some frequent shoots using this lens – I just hope the clouds are moving a little quicker next time!