The Z-35 needs assistance--

alignment1

alignment1

Well-known member
Hey all-

After being inspired about a year ago from Edweirdo's 35mm adapter, I finally have mine built.

Through extensive research, I finally ended up going the 'Jetsetmodels' route, (thanks Daniel) with one of his vibrating GG holder's.

However- I am still having image issues

I seem to be getting quite a bit of vignetting and extreme blurring around the
edges of the frame.

Here's the setup:

DVX100B camera
72mm Cine HD achromat lens (india)
72-55 step ring
55mm circluclar polarizer filter (no glass)
EOS extension tube set (sections 3, 3, 2)
VH-57X Ver. 2.0 (w/ rheostat)
Canon Ee-A focusing screen
Multi-Coated UV filter (dust cap)
Canon FD to EOS mount (with glass)
Canon FD 50mm 1.4f lens

I've tried different variations of the extension tubes, doesn't seem to change
much, (still vignette/blurry edges).

The FD lens is wide open, (but I also tried stopping down 1 or 2 stops. The more I stop down- the darker the image, and more vignetting is happening.

The camera settings: It's in MF, autostabilizer is 'OFF' iris is wide open to
about 2.4 or so.

Shutter speeds 1/24, 1/48, 1/60

I feel like the vignetting is happening at the focusing screen. When I look at
the lens through the focusing screen(off of the camera) it looks like there
might be a bit of vignetting. Any suggestions?

I've seen footy on here using similar setup with great results.

I know I can somewhat correct the problem in post, but I'd much rather fix the problem at the camera.

Pics/Vids to come( Iknow it's easier to 'see' than 'read' :))

:dankk2:


Thanks

Zack
 
Last edited:
...also in camera settings would be helpful, i.e. DETAIL level, Coring...etc. if anyone has some good set-ups-mucho aprreciated!!

Z
 
Zack,

I have a spinner. In my setup I also went in this order of R & D

1. Magnifying glass LOL! really.
2. cokin & sunpak close up filters
3. indian achromat
4. first gen Cinevate achromat which at that time was similar to the Redrock.
5. sgpro achromat.

Since i use a spinner, I cannot say that my solution would be the same for you, BUT, the sgpro achromat gave me edge to edge sharpness and very little CA at the very edge. The cinevate gave a perfect rectilinear image and the sgpro has slight barrel distortion at the overscan boundaries.

Post a still frame of a focus chart so we can help you out. Dont post leaves and cluttered stuff, this way i can compare with my own R & D and mark your progress in a repeatable scenario.

Ted
 
I have to agree with Ted. When I built my spinner I went with Ted's recomendation of the sgpro achromat. I made one additional enhancement that helped with the hotspot and that was to add a condenser lens between the SLR lens and the GG. I used the front lens from an old set of binoculars. That made a noticible difference.
 
thanks guys--

I've been to Wayne Kinney's site (shoot35) but can't seem to find if there is a way to purchase an achromat alone, however, I haven't bothered Wayne with this yet. I was wondering if anyone else has info on how to acquire one of these.

Also* I saw a Redrock Micro 72mm achromat on E-bay yesterday--would that be comparable?

FYI- I've done a bit of research, but I'm still very much a newbie when it come to optics--thanks again guys!

Z
 
I just emailed Wayne directly about the achromat and took care of it that way.

By the way, I did order an SGBlade from Wayne and it will be replacing my DIY adapter.

Building an adapter was very educational. I learned a tremendous amount and have a deeper understanding about how it works and what causes issues...and how to fix them. Not to mention all the practice I got using it. All of that will come in handy once I get the SGBlade.

It was a great project and I may still use it occasionally even after I get my SGBlade.
 
mvansomeren said:
Building an adapter was very educational. I learned a tremendous amount and have a deeper understanding about how it works and what causes issues...and how to fix them. Not to mention all the practice I got using it.
Click to expand...

Yeah, I definitely have a deep appreciation for the undertaking of one of these things. Obviously, budget is an issue, so my initial endeavor of this adapter was with the notion that I could build one of these for a couple hundred bucks... well about $700 later I'm finding it is a bit of a can of worms. But that's the price you pay for education I guess:

--first it starts with the adapter and all of the parts you can get from home depot, and of course the holy grail of them all, the GG, which becomes an egghunt in itself, then there's the standard 50mm 1.4 lens for the front etc..

well then.... you need Rails!!

and then of course a follow focus...considering the length of my adapter (--and believe me I don't get to say that much, so I'm enjoying this moment..:huh:)

my follow focus isn't quite on the rig yet, but it's made of legos, YES LEGOS(thanks to a dude over at the HV20/30 forums). A little flimsy, but gets the job done for now.

But I still have higher standards for picture-and edge to edge clarity is a must!

So, I'll push on--but yeah for now this is a learning tool for the field, when my chops get better, I become more knowledgable about optics, cinematography, lighting, etc.. and of course my wallet permits, I will then step-up and invest in the real deal.

If an achromat will help me achieve edge-to edge, then I want in!! It's too bad however, I just spent $115 for my achromat from India-

oh well, it achieves some fun stuff on it's own though, like reading the fine print in contracts, starting a fire in a pile of leaves, etc.
 
...I spoke w/ Daniel from jetsetmodels he seems to think that the problem may lie in the Canon FD to EOS mount- more specifically the glass.

Truth be told, If I take apart the adapter so all that's attached is the front end section (Canon FD 50mm through to the gg section), when I look through the gg (canon Ee-A focus screen) to see the image with my own eyes as opposed to through the cam, I can't see I nice flat image, it kind of vignettes--I have to move it around to see the entire image.

Now, I don't know if that's the nature of the focusing screen, but I've seen other pics online of other people's adapters, and when they hold up this section of the adapter so you're looking through the gg, I see a nice flat, edge to edge picture.

The Extension tubes are Canon EOS, does anyone know if Canon EF lenses mount directly to those? I see a bunch of Canon 50mm f1.8 lenses for about a $100 bucks on ebay- would that be worth a try?? Anyone??
 
ok update here--

I picked up a CINEVATE 72mm achromat to replace the Indian achromat, definitely better e2e.

I have definitely narrowed the vignette problem down to the Canon Ee-A Focus Screen. I had the adaper apart today, (replacing motor) and held up the gg to a light and could very faintly see a circle in the focus screen! I hadn't noticed it before, but with a careful eye a circle is definitely seen. Everything in the circle is a pinch lighter, and outside, (the vignetted area is a pinch darker/denser or something. It looked something like this, (not as extreme):

attachment.php


Is this the built in condenser that I am seeing?

Can anyone give me guidance as to which screen I should try- I'm thinking of ordering the Canon Ee-S. I know the Nikon D is the holy grail of gg but if any one could share some recent ideas on available focus screens that will rid me of my vignette issues.

Is there a gg thta has an even matte without hotspots, do they need condensers??

thanks

Z
 
You must log in or register to reply here.
Back
Top