Fuji GA 645 Zi problems

[mark_muse]

I am having two problems with my Fuji GA645 Zi that I have not seen mention of in this or other forums:

 

1. The autofocus lense movement is so abrupt that it vibrates the camera and tripod to the detriment of the image. I no longer use a cable release with it because if I release by hand I can pause between focus and expose to allow the vibrations to settle. I am using a Tiltall tripod which should be plenty beefy enough for a camera this light.

 

2. I am experiencing vignietting on my films. I have not done a methodical test to see if the problem is worse at some focal lengths or aperatures, but the problem exists in all of my exposures. I tend to use smaller aperatures, but all focal lengths.

 

I sent the camera to Fuji NJ for for a D&C, along with some negs and a note asking them to fix this problem. They did not specifically mention the light fall off problem but said the camera was adjusted and operating properly. However, the problems persist.

 

Anyone experiencing either problem? Insights?

 

Thanks

[bleck]

Do you have any filters mounted, UV or otherwise? Or maybe a non-factory made lens-hood? I'd be inclined to suspect that's what's causing the vignetting you're seeing.

[robin_barnes]

Mark I can't comment on your first problem but with regard to the second I know what you mean. When I was looking for a lightweight medium format camera for travel and walking trips the Zi seemed like the obvious choice. A local camera store (I live in the UK) let me shoot a test film (Provia 100F) with one before deciding whether or not to buy. I liked it very much it seemed to be just what I was looking for until I saw the test slides! Sharp images certainly but light falloff was present at all zoom settings and all normal working apertures. I was very disappointed. To make sure that I hadn't just got a faulty camera I did the same test with another one and got the same results. So I decided not to buy one and bought a Bronica RF645 instead - no falloff at all with my 65mm lens and only a little with my 135mm (gone by f8).

 

I'm afraid you are just going to have to live with this problem as my tests suggest that all Zi's are like that. I don't think you will find any comments on this issue in the archives (other than one of mine a year or so ago in a discussion on the RF645 if I remember correctly) as most owners of the Zi who frequent this forum seem to mainly use negative film with which the effect is apparently less noticable.

[andrew_ito]

I've had a 645zi for a few years now and haven't noticed either problem that

you've experienced. After reading about the zi for a while now, your post is

the only one i've seen that describes these problems. You might want to

compare your zi with some others and see if they all have the same issues.

[scott bacon]

<p>I've also had the Zi for a few years, and I've haven't experienced the camera

shake or vignetting problems you have. Personally, I've found this to be a great

travel camera. I recently exposed about 60 rolls of Fuji Astia and ProviaF on a 7 week Europe trip. I went back through those images just

to check for vignetting. A few of the images show <b>very mild</b> light

fall-off. They seem to be those taken with the lens zoomed to its widest focal

length. But this is only a couple images out of a couple thousand. You can look

<a href="http://www.naturalorderphoto.com/gallery.htm">here</a> (bottom of page)

for yourself. 95% of the images displayed are scanned full frame and not

cropped.</p>

<p>I think you have a lemon. Or perhaps, there are different vintages of this

model? I don't know.</p>

[ed farmer - mount laurel,]

I never had light fall off problems with my Zi. I sold it for completely different reasons.

[brad_hiltbrand]

I did see some slight vignetting when using the smallest

aperatures available in very strong light (slide film). However,

since the lens seems sharper and has plenty of DOF at F8-16

for most of my photography, I am no longer trying to use the

smallest aperature I can. It is simply not necessary and does not

always produce the optimal image.

 

As for your autofocus shake problem with cable release, the

autofocus should be complete and the lens still at the time the

shutter opens. If you are convinced this is the source of trouble, a

simple workaround would be to use the manual focus button

and select an appropriate distance for your aperature and DOF

requirements instead of using AF when using cable release. MF

eliminates the autofocus time lag and may help. You could even

use the AF to check distance, and then switch over to manual

using the same distance. I would still look to your tripod/head as

being the most likely source of motion blur.

 

I find myself using MF more for landscapes since the AF does

get confused sometimes depending on conditions. If your

subject is between 5m and infinity, this approach seems to work

very well.

 

Scott, as an aside, your images are one of the main reasons I

decided to buy the GA645Zi last spring. Thanks for sharing! I love

this camera. It is not perfect, but it sure strikes the right balance

for me.

[philip_roberts1]

Mark, I appear to see the same problem you do regarding light

falloff. However it only occurs for me in very strong light (blue sky/

white clouds/full sunshine 1/250 F16 typical). Changing aperture

has no visible effect (I shot a test reel - Provia 100 - to check on

a glorious day in East Anglia, UK). I took shots at 90 and 180

degrees to the sun - no difference. Problem is more pronounced

at the 55mm end than the 90mm although still visible there.

Shooting using flash or in more difused light seems to be OK.

 

My feeling is this is purely a lens design issue. In all other

respects this is a MF camera that makes me go WOW! Light,

portable, highly speced it is probably the ultimate travel

camera...provided you treat it as the zoom compact it is.

 

I have no issue with shake - this camera is a delight to

handhold, even at low speeds. The lens is razor sharp and once

you understand the idiosyncratic focusing, darned accurate too!

 

It is worth noting that many landscape photographers (including

top class ones like Colin Prior) use a centre spot ND filter. Why?

Light falloff of course. The curse of any wide angle photo in

strong light.

 

Print film will be more forgiving I suspect, I have yet to use any in

anger.

 

Please all, get in touch with me and share your thoughts/

experiences.

[a._governale]

Can anyone suggest a source for a Centre Spot Filter? I havent had any luck in locating such a filter....Maybe there is another name?