Advice on 10 stop filter please.

[Argee]

I have recently bought a Hitech Pro 10 stop square 85mm filter for my P size filter holder. I have been practicing fitting it and getting used to setting it up on my Canon EOS 60D and the preparation for getting the correct exposure. I read however that it is possible to use "Exposure simulation" to "see through" the filter, when fitted, and possibly then use exposure compensation to achieve the correct settings. Or is it all guesswork? Does this mean that in live view I can see the actual image change when setting exposure compensation, or do I have to switch between live view and the exposure simulation menu all the time. I have enabled expo sim and tried it but cannot see any apparent change in live view when I change exposure comp. I have made some test shots and CAN see the change in the finished image but can I see it in real time in live view?

Also I notice that when I fit the filter in the nearest of the three slots in my holder, the gasket does not fit snug to the lens. There is a slight gap between filter gasket and lens rim. I would have thought some light would get in here. Am I correct or am I missing something?

[donoreo]

I cannot see through my Hitech 10 stop and have to go to manual mode. Before putting the filter on, take a reading with the camera and then switch to manual mode and adjust it by 10, or so, stops. You can use the handy guide that came with the filter or as I do I use an iPhone app.

When you ordered the filter, did you get the right one for your holder? They have different gasket sizes (thickness) depending on the holder. Email them and they will help you out on that.

[JonnyM]

I have a 60D and a Hitech Pro 10 filter which I place in a Cokin P filter holder. You cannot see through a filter that dense to obtain a correct exposure or composition in camera. I do what donoreo does, manual mode, add 10 stops to the metered exposure then put the filter in the holder, carefully so as not to knock the focus barrel, camera level etc. Even then it can still be pretty much trial and error depending on the subject and the intended result, but atleast you have a benchmark exposure. I have no idea about 'exposure simulation'.

Yes light will get in there. You have to specify what filter holder you are using to determine the correct gasket thickness. I still get light leaking into the lens even with a snug fit so I sometimes cover the filter holder with a black cloth to reduce this.

[Argee]

Originally Posted by JonnyM

... I still get light leaking into the lens even with a snug fit so I sometimes cover the filter holder with a black cloth to reduce this.

Yes, I also heard once about someone covering the viewfinder with a black beanie hat as well. Thanks for the advice.

[JonnyM]

Yes you should cover the viewfinder as matter of course if your eye is away from it, especially with long exposures. My camera came with a little rubber device for this purpose, it stays on the camera strap to stop it getting lost.

[Argee]

Originally Posted by JonnyM

Yes you should cover the viewfinder as matter of course if your eye is away from it, especially with long exposures. My camera came with a little rubber device for this purpose, it stays on the camera strap to stop it getting lost.

Yes thanks, but I meant as well as the eyepiece cover that we all have on the camera strap. I guess it is an extra bit of insurance against light creeping in which I am told can happen.

[Argee]

I have investigated the gap left my the ill fitting gasket and it apparently is a known manufacturing problem and now all new Hitech ND 10 stop filters are to be supplied with a modification to the gasket. Unfortunately it is not retrospective so all previous buyers like me will not be given any help from Hitech. Fortunately my supplier is hoping to build something using the gasket foam used by Hitech to make a better seal with the lens so I shall post back with any results.

[donoreo]

Originally Posted by Argee

I have investigated the gap left my the ill fitting gasket and it apparently is a known manufacturing problem and now all new Hitech ND 10 stop filters are to be supplied with a modification to the gasket. Unfortunately it is not retrospective so all previous buyers like me will not be given any help from Hitech. Fortunately my supplier is hoping to build something using the gasket foam used by Hitech to make a better seal with the lens so I shall post back with any results.

that is odd. When I had their older 10 stop they sent me a free gasket to try.

[Argee]

Originally Posted by donoreo

that is odd. When I had their older 10 stop they sent me a free gasket to try.

Mine was bought Jan 2012. I know there was a problem with the earlier versions of this filter which supposedly was solved with the updated gasket now being supplied. However, I gather that there have been many recent complaints to Hitech regarding this so they are possibly reluctant to admit this problem exists again.

I add that I am using it with a 10-24mm wide angle lens with 77mm thread. I don't know whether it would be so apparent if used with a smaller lens diameter.

[Argee]

The final chapter! I went to my dealer and he had received the felt gasket modification which he tried to fit. Didn't work did it! No matter how he attached it there was still light leakage from around the filter as it didn't have a snug fit. We noticed however that all modifications to the Hitech ND filter NOW have a printed disclaimer recommending using a black cloth or otherwise to limit light intrusion. I think they now realise they have a problem! I asked about the square Lee big Stopper and he said the Lee although more expensive, it was a better configuration and fitted with no leakage. I would have bought one except I would have to also buy the Lee filter holder at extra cost. So the lesson is again " buy cheap … buy twice!"

Conclusion was I need a ND 10 stop filter so I asked my dealer if he could convert my square filter to a circular one, accepting this was my only alternative, or a full refund which he offered. I decided to have my filter machine cut down to a 77mm circular one which he promptly did and mount onto a fitting ring, so I now have a perfectly usable circular HD 10 stop filter. I know my previous comments preferred a square ND filter, but I now know I have something that works against something that is suspect. I understand that to use an extra square ND grad is going to present a problem but I have to accept this and figure out how to get around it.

Without overtly advertising my supplier I have to mention that he was very knowledgeable and fully understood the problem although completely unaware of it until he contacted his source and found that it was well known and documented. He made all modifications free of charge and gave me a complimentary gift for my trouble. So I can only recommend anyone who has bought a P size square Hitech ND 10 stop grad filter and has the same problem either PM me or get in touch with them for any info and advice.