Step up rings and ND filters.

[MRfanny]

Another beginner question for you all,

I'm considering buying the Fader ND filter of ebay for the gh1 stock lens with 67mm thread and zeiss with 55mm thread. Now someone had mentioned that it is a good idea to get a bigger filter to reduce vignetting/ or something of the like on the gh1 so I am looking at the 72mm thread one with 77mm front glass or maybe the next one up. What I like about this particular product is it gives me the flexibility to adjust from ND2 to ND400 on the fly, letting me experiment and understand the use of ND filters a bit more before I become pedantic about image quality.

My question here is will I have any issues if I purchase a set of step up rings and combining them, kinda creating an ever growing cone hood depending on how much i need to step up as apposed to a specific step up ring say 55to72 that is a lot thinner in profile. Should I just buy two separate filters to match each lens size?

thanks again.

 

[Terry]

The 14-140 takes a 62mm. I thought the ND's that you are talking about actually are made with the filter being bigger than the 62mm of the rear thread. 72mm with 77 front glass just seems too big and I wouldn't go that big with step up rings. Also not sure if you will get any weird reflections with the filter glass then being pretty far from the front element.

The 14-14 isn't that wide that you should have a vignetting problem on a 4/3 sensor. The bigger problems I've had have been on a full frame sensor.

Can you post a link to the ND you are thinking about.

 

[MRfanny]

yeah my concerns were if I use too many step up rings I may get unforeseen issues such as darkening of the edges and possibly reflections as you said. I may just get the singular step up rings for each lens diameter so it's consistent but may look strange, resembling a top hat brim...ha. I'd like to know if its common practice to get a slightly larger filter or not. Common sense, though more expensive, says to just get two filters to match each lens thread size.

Here is the ebay link to the fader nd. Its a cheaper alternative to the more expensive Singh Ray Vari ND.

http://cgi.ebay.com.au/Fader-ND-Fil...s?hash=item20acf1c3c7&_trksid=p3286.m63.l1177

They apparently come in 52mm to 82mm but run out of stock very quickly. And here are the two examples of the step up rings I am talking about.

http://cgi.ebay.com.au/pro-Step-Up-...ash=item5185ef2bdc&_trksid=p4634.c0.m14.l1262

http://cgi.ebay.com.au/55mm-to-67mm...s?hash=item335289ca14&_trksid=p3286.m20.l1116

Ignore thread numbers. As you can see the second one is a flat profile, keeping distance from lens to filter a minimum whereas the first increases distance the more you step up.

 

[Terry]

This is the one that I saw and was going to try. The 62mm already has a 67mm glass. For the 14-140, I think this should be fine and is what I plan to order.

The only lens I have a problem with is the Sony/Zeiss 24-70 with my A900 and there I have a full frame sensor and vignette at the wide end with a slim 77mm thread and 77mm glass whereas here I would get 82mm glass on a 77mm thread. The G1 should not be as bad as this lens for a number of reasons.

 

[MRfanny]

so do you think getting a 72mm-77glass would be overkill? especially when mounted to my zeiss 55mm primes? would just like to avoid any vignette or "ghosting" and "flaring"? I really don't know what i'm talking about. =)

If i think rationally, it does sound abit overkill..ha. I think ill just get the 62mm-67glass and see how it goes.