Black Reference, ND Filter and Rodenstock Aperture Mount lenses

[eisbaer]

Hi,

just thinking about buying some Grad ND Filters, probably from Wine Country Cameras.

How do I do a black reference(or LCC) if the ND Filters are mounted?

I have two Rodenstock lenses with Copal Shutter and two in Aperture Mount. With the Aperture Mount lenses, I have to do the Black reference with the lens cap. I can't close the shutter as with my Copal Lenses.

Now when I mount a Filter holder... must I remove the Filter holder (and probably the Adapter Ring) so I can put the lens cap on for the Black Reference? This would be some work for each shot. ;-(

And the LCC. Almost the same problem, but here I could remove the ND Filter and put an 100mm LCC "Filter" into the holder. If I can get a 100mm LCC "Filter" which fits into the holder. Any ideas where I can get one?

I read that the wine country camera Filter Holders have no light leaks. So for the black reference, could I get a 100x100mm black opaque plastic wich closes the lightway?

I hope you understand my problem, and probably there is a simple solution, which I can't think of at the moment.

Thanks for your help.
Frank
(Phase One IQ4 150, Rodenstock 40/70HR with Copal and 23mm and 138mm in Aperture Mount, Alpa STC and Alpa Plus)

 

[jng]

Hi,

just thinking about buying some Grad ND Filters, probably from Wine Country Cameras.

How do I do a black reference(or LCC) if the ND Filters are mounted?

I have two Rodenstock lenses with Copal Shutter and two in Aperture Mount. With the Aperture Mount lenses, I have to do the Black reference with the lens cap. I can't close the shutter as with my Copal Lenses.

Now when I mount a Filter holder... must I remove the Filter holder (and probably the Adapter Ring) so I can put the lens cap on for the Black Reference? This would be some work for each shot. ;-(

And the LCC. Almost the same problem, but here I could remove the ND Filter and put an 100mm LCC "Filter" into the holder. If I can get a 100mm LCC "Filter" which fits into the holder. Any ideas where I can get one?

I read that the wine country camera Filter Holders have no light leaks. So for the black reference, could I get a 100x100mm black opaque plastic wich closes the lightway?

I hope you understand my problem, and probably there is a simple solution, which I can't think of at the moment.

Thanks for your help.
Frank
(Phase One IQ4 150, Rodenstock 40/70HR with Copal and 23mm and 138mm in Aperture Mount, Alpa STC and Alpa Plus)

The short answer is yes, you can incorporate a plastic plate into the WCC filter vault. The thickness around the edge needs to be 2mm to fit inside the vault's groove. See the following thread (read through post #5 for the technical bits):

H&Y Filter System with a Technical Camera

I've been using the H&Y system for the last several months. I had not heard of it before reading Tim Parkin's very thorough review of filter systems at OnLandscape (paid content). The real reason this system interested me was the opportunity to create a LCC card and dark frame that attached...

www.getdpi.com

Hope this helps.

John

 

[tcdeveau]

Definitely look into the HY thread John posted.

Just to play devils advocate, how necessary are grad NDs for the work you’re doing on the IQ4 150?

For my own work, I’ve found it’s simpler just to expose for the highlights and handle the “filter” in post. Dynamic range of today’s sensors is so good I don’t even remember the last time I used my own grad NDs. The filters and the holders just add bulk to the bag. If it can’t be done in a single shot, I just exposure bracket and combine in post.

Plus, the weight of a filter holder and filters on the copal 0 lenses makes me nervous, esp applying the force it takes to slide the filters up and down when attached to the lens. Maybe I’m being overly cautious and it’s a non-issue.

YMMV may vary of course (and maybe they’re necessary for your work) but I’d skip grad NDs personally.
-Todd

 

[dougpeterson]

The IQ4 can use a pre-recorded black frame. In our testing we saw virtually no difference between pre-recorded and in-situ black frame options, and obviously using pre-recorded black frames is far more convenient.

So my question is why are you doing a dark frame at all?

 

[eisbaer]

Thanks a lot for all the input.

The HY Filter set seems to solve my problem very elegant, so I ordered one with Grad Filters.

I am with Todd in regard of regular NDs as With frame averaging I can do the same just better without noise. Grads are very interesting for me as I do a lot of extremely High Contrast landscapes. As the IQ4 has an incredible dynamic range and with the Raw histogram I can get perfect ETTRs from Raws, but I hope I can handle 2-3 stops more of DR with Grads as I am very often at the Limit. As I have seen in the last years how much better a perfect exposed and developed RAW File is compared with an HDR (and I know how to handle HDRs and to do HDR postprocessing in PS) I try to avoid HDR if possible.

To Doug: I got the information in my POCP Workshop and In my dealer briefing for the IQ4 that the prerecorded Black References are Fine up to 1 second of exposure time. If one needs longer exposures I was told it’s recommended to take a Black Reference. As you are for sure much more experienced then me and you have surely more resources - up to which exposure time do you think one can skip the Black Reference?

thanks Frank