Pentax 15mm Limited and square filter systems
Mhuni
500px
http://teamworkphoto.com/shop/index.php?main_page=product_info&cPath=78_261&prod...
Have a look around the site above for an idea of prices etc.
This is the manufacturers website, they are really helpful and a top notch bunch of people...
http://www.formatt.co.uk/default.aspx
No I don't work for them, it's just a good product at a fair price...
Cheers Jules...
My viewfinder is 576,000,000 pixels.
My other viewfinder is 5.76,000,000.
www.exaggeratedperspectives.com
Instead of protruding forward away from the lens, they recede backwards over the end of the lens allowing the filter holder to sit much closer to the front element of the lens reducing the risk of vignetting.
I wondered if the in-built hood would interfere with the receding adapter ring?
Mhuni
500px
If it doesn't work you'll all be the first to know!
They also do ordinary adaptor rings which may work as an alternative...
http://www.formatt.co.uk/stills-filters/hardware-100mm/wide-angle-adaptor.aspx
Someone has to be the guinea pig here

Cheers Jules...
My viewfinder is 576,000,000 pixels.
My other viewfinder is 5.76,000,000.
www.exaggeratedperspectives.com

A 100mm NDgrad works a treat on a DA12-24 where the front lens element is huge. However, stick the same 100mm NDgrad on a small lens and you are only using a tiny part of the grad

You'd probably find that an 'A' sized filter would be more suited to a 49mm thread... or a 'P' at a pinch.
Of course, for the Big Stopper it won't matter. (Except the cost!

... the other thing is how far the lens protrudes from the body. You may find that a Lee 100mm holder will hit the handgrip!! (Sorry, I don't have the 15mm to check)
HTH,
Matt
http://www.mattmatic.co.uk
(For gallery, tips and links)
Even the Cokin Z-Pro filters I have have slight colour casts

Lee are probably the only ones that have next to none, or none - but you definitely pay for it!

A slight magenta cast is no big deal and easily neutralised in Photoshop

It would definitely be a shame to pay out for lovely Lee NDgrad filters and find that they're not actually NDgrad but adjustable grad on a smaller lens

Matt
PS. Apart from straight ND, I find I'm using grads less and less. The dynamic range of the K7 helps, and where that's not enough two or three shots work just as well - gluing them back together in PP.
http://www.mattmatic.co.uk
(For gallery, tips and links)
Jules, have you used this with a DA15? I ask because it says this on the Teamwork page:
Instead of protruding forward away from the lens, they recede backwards over the end of the lens allowing the filter holder to sit much closer to the front element of the lens reducing the risk of vignetting.
I wondered if the in-built hood would interfere with the receding adapter ring?
Just got off the phone with them and they can't make it fit

http://teamworkphoto.com/shop/index.php?main_page=product_info&cPath=78_261&prod...
Not before the Postman had collected it

So it'll just have to go back and I'm back to the polariser idea, though Teamwork did suggest the Lee push on but I have no experience of that particular system and ain't about to throw masses of wonga their way either when it appears my other filter holder system is now redundant!
Cheers Jules...
My viewfinder is 576,000,000 pixels.
My other viewfinder is 5.76,000,000.
www.exaggeratedperspectives.com
Matt - I'd never thouoght about the problem of the grads with a lens with a small front element before - thanks for bringing that up - and cheers to Mhuni and Jules for their input too - It's not looking so hopefull that that I'll get the sysytem I really want to work properly on it.
Such a shame as I really like the 15mm but this problem is throwing a real spanner into the works -all my other lenses I figure would be fine, but the one I reckon would be the most useful with the filters is the one causing the headache!
Thanks again - might have to consider selling it and going for the DA14m or DA12-24 - had some specific types of shot in mind that I'm not sure I can pull off without certain fiters.

'The RAW is the score and the print is the performance' - Apologies to Ansel Adams
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Cheers Jules...
My viewfinder is 576,000,000 pixels.
My other viewfinder is 5.76,000,000.
www.exaggeratedperspectives.com
I wondered if the in-built hood would interfere with the receding adapter ring?
Been looking at the 15mm Ltd myself and figured this would be an issue. Only solution that I could work out is either build out the filter thread to reach beyond the fixed hood or... grind the hood down

The hood on the 31mm Ltd causes me the same grief and is one of the reasons why that lens gets less use than it should!
Spirit_of_will
Fan and user of quality Pentax Shiny Kit
WEBSITE www.willbartonphotography.com & www.inspiredlightimages.com
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Noone's commented on the idea of using a filter (element removed if desired) to get you beyond the in-built hood. Wouldn't this work? I'm sure I read about someone doing this elsewhere - and without vignetting.
What's the thickness of filter that you need to get beyond the hood? 5mm? Or is it more? Surely if you have to go much beyond the hood then you'll run into vignetting issues? Otherwise Pentax would have designed a larger (half useful?!?) hood?
Spirit_of_will
Fan and user of quality Pentax Shiny Kit
WEBSITE www.willbartonphotography.com & www.inspiredlightimages.com
Will Barton Photography: Landscapes, Cityscapes
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I guess it was a slim filter they referred to.
Mhuni
500px
Haworth
Member
North West UK
I ask as I am wanting to invest in one of these systems (probably Lee if/ when the filters become available). On the 15mm Ltd the lens hood protrudes slightly when retracted and I am worried the filter holder may not be able to screw in properly. It would be a shame if there were a problem as this lens is the most likely one I would use the system with -landscapes with the graduated filters or the 'Big Stopper' etc.
Any thoughts /experiences / comments welcome.
Cheers
H.
'The RAW is the score and the print is the performance' - Apologies to Ansel Adams
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