Minolta 9000: Checking shutter and focusing screen, adjusting the mirror, replacing parts, cleaning

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Andreas Thaler

Andreas Thaler

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D.jpg

The Reveni Labs Camera Tester in action.

I reconstructed the photo, so my jumper tape solution is not visible


4000.jpg

1/4000 s


2000.jpg

1/2000 s




1/1000 s




1/500 s




1/250 s




1/125 s




1/60 s




1/30 s




1/15 s




1/8 s




1/4 s




1/2 s




1/1 s


As you can see, both shutter curtains virtually move evenly across the film field. Only at 1/4000 s is there a larger deviation, which results as +1.37 EV exposure difference in the image.

I can live with that as a hybrid photographer, the correction is then done in Photoshop, if at all necessary

I don't even know if I can adjust the shutter speeds at all, it probably takes more than turning a trim potentiometer. I'll look in the service manual. But I'll be careful not to mess around here, this is a very good result.

I assume that this camera has never been serviced (assumption) and for its about 40 years it has held up excellently.

Since the other functions also work plausibly, this 9000 is ready for testing with film. As soon as the motor drive and battery holder arrive, we'll get started.

Reveni Labs Camera Tester: New perspectives for professional and private camera repairers

I wonder if the light source is bright enough to work on large format graflex slr's with focal plane shutters, as well as speed graphics. Currently I have a phocron, sadly no longer made. I have made a rig for the light source for this, so it can be inserted into the camera close to the meter...
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ic-racer

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Recent thread I had about adjusting mirror angle:

Setting SLR Mirror Angle With A Collimator

In most all SLRs the mirror pivots at the upper portion of the film frame. Mirror angle has very little effect in that area, as the pivot is not moved with the mirror angle adjustment. In the viewfinder, the top of the film frame is the bottom of the viewfinder image. So, adjusting the mirror...
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I would still like a collimator. But I didn't find anything on eBay.

So I am very hopeful about the current project from @Reveni-matt:

Designing a new affordable production-ready Autocollimator

Hi guys, Matt from Reveni Labs here. I'm working on designing an affordable autocollimator to release in 2025. Trouble is, I have no hands-on experience with a real autocollimator so I'm piecing things together bit by bit just from what I'm reading. I'm working to separate the "gotta haves"...
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In the case of the 9000, it obviously works by adjusting the mirror through the viewfinder.

The auxiliary mirror underneath can be adjusted with another adjusting screw; it should be responsible for the AF.

Obviously, the position of the main mirror has no effect on the auxiliary mirror.

I will know more when I evaluate the test film (motives from Vienna, no test board).
 
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Paul Howell

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My 3 working bodies all seem to have accurate shutters, my primary body was cleaned and new seals installed by Tempe Camera just before the pandemic, they tested the shutter before agreeing to work on it, if the shutter is not accurate and they cannot adjust it they will turn down working on it.
 
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Replacing parts and cleaning

Another 9000 from my squad of six works, but is dirty and heavily used.






It's the one with adhesive tape on the handle and the back panel.


I want to clean and improve this 9000 with replacement parts from my stash.




On the left is the as good as new 9000, whose shutter is unfortunately blocked and which I don't want to try to repair because I would have to take the camera apart and that would be a mission I'm not prepared for right now.

But it's always good to have new spare parts and so it's now member of my spare parts stock.

On the right is the 9000 that needs to be improved.

I've already removed the adhesive tape, underneath is the plastic handle without a covering.

There's actually no difference to be seen and so I'm abandoning the idea of replacing the handles. I'm saving the nice handle for other 9000s that need more.

But I'm replacing the base plates.




This is what it looks like under the base plate of the as good as new but faulty 9000.




And this is what the heavily used but functioning 9000 looks like.

Some dirt is visible and lack of lubrication on the left transmission lever, which already has bare spots.




The third screw on the base plate of the donor 9000 could not be loosened. My last option was to remove the screw head with the Dremel and a diamond cutter.

I slipped, but I can cover that up with paint later.




The two stuck mirrors of the as good as new 9000.




Dirt on the heavily used 9000.




Here too, contamination and lack of lubrication.






I clean as best I can with Zippo lighter fluid and apply a little grease to the transmission lever.

This is better than nothing, actually the entire mechanism should be cleaned and lubricated, but this would definitely exceed my „mission of improvement“.




The adhesive on the outer plastic eyepiece part has come loose and the part moved inward.




I can grab it with the minisuccer, but the adhesive residue prevents it from fitting into the holder.

This means that I have to remove the top cover to repair it.

I am prepared for this from the section of a 9000:

Minolta (Maxxum, Alpha) 9000 AF: Removal of the mirrorbox/assembly, investigating the aperture issue, replacing the sticky damper in the shutter unit

An SLR from 1985 that is not only beautiful but also technically innovative, but which you don't read much about: https://en.wikipedia.org/wiki/Minolta_Maxxum_9000 Inspired by @Paul Howell in...
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But first I mount the replacement base plate.




Good thing I am going to take off the top cover, there's rust here.
 
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Andreas Thaler

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After removing the top cover, I can work on the eyepiece part in its holder. Tough adhesive needs to be removed.




I don't want to deal with that now, so I'll get an intact replacement from my stash.




In order to fully remove the top cover, I desolder these two cables.




I also have a replacement for the top cover. The one at the bottom looks better.




I would also like to replace other parts that are worn out from my stock.

Here are the remains of the section of an abandoned 9000.




I will replace these parts.




The 9000 is now complete with spare parts.




These parts are being cleaned with cleansing foam, water and Durgol descaler.
 
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Cleaning/Lubricating





Cleaning with isopropyl alcohol.






Cleaning the accessible contacts with electronic cleaner.




The ball bearing for the exposure metering rotary switch gets some grease.


Electronic troubleshooting

After assembling the 9000, I tested the functions.

Setting the shutter speed with the slide switch under the mode selector worked for a short time. Then the camera started to run on its own and counted the times down to bulb.

The slide switch for setting the aperture did not change anything on the LCD.

ISO and exposure compensation also ran through the settings automatically.

An electronics error.

What could be the cause, what did I change by disassembling and reassembling it?

I suspected moisture from cleaning the top cover. I probably hadn't dried everything thoroughly.




I saw that the unit with the mode selector was attached to the top cover with three screws. There could still be moisture here. So I dismantled the unit.




And indeed, there was a drop of water on this conductor track which I removed.




Here you can see the connection to the camera circuit via a flexible circuit board.




This wiper runs on the conductor track that I dried.




I reassembled the top cover and documented before the soldering points on the circuit board to make sure I had connected the cover correctly.








Mission accomplished

This 9000 also works and has now been cosmetically improved.

The handle looks better without the coating coming off. Nothing sticks here anymore, so stripping is an option if the coating detoriates.

I cleaned all external parts with isopropyl alcohol on a microfiber cloth.
 
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Andreas Thaler

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After testing the plausibility of all functions, I finally measured the shutter speeds with the Reveni Labs Camera Tester.

Everything was perfect.




1/4000 s




1/2000 s




1/1000 s




1/500 s




1/250 s




1/125 s




1/60 s




1/30 s




1/15 s




1/8 s




1/4 s




1/2 s




1/1 s




I will also test this 9000 with motor drive, program back and film.

Stay tuned!


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Fortunately I don't see any rotting/sticky mirror shock absorbers or light seals on my 9000s. There was obviously progress in materials at that time.

Thanks for the hint about setting the shutter speeds, I'll look in the service manual to see what it says about that.
 
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BMbikerider

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The Minolta 9000 was my first AF camera and well ahead of the opposition at the time. Go forwards a few years and my last Minolta AF camera was a Dynax 9 - what a gem that was. Up there with the best, unfortunately, it came as film cameras were being phased out in favour of Digital so I jumped ship to Nikon. That was around 2002 and since then I have only seen two up for sale in a dealers window and they didn't stay there a day before both were sold.

Probably the 9000 and the 9 were my all time favourite cameras at the time.
 
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Reconstruction of the covering on the handle



At a third 9000 I see two options:
  1. either remove the covering and expose the plastic handle underneath, which doesn't stick (see above in the thread), or
  2. touch up the area with Sugru.



I tried the latter with the help of a spudger with a flexible blade.




After it dries, I'll see what the color looks like in the end and whether I need to polish it.

Before applying it, I cleaned the area with isopropyl alcohol.

I'm curious to see if it holds.

Here, too, the primary concern is improvement rather than restoration of the original condition.

Repair work: Sugru, the multi-purpose mouldable glue

For small repairs on cameras, I like to work with Sugru, a mouldable adhesive that can be kneaded and shaped. After hardening, it replaces plastic. https://sugru.com/ https://en.wikipedia.org/wiki/Sugru Here are two projects where I used Sugru. Alignment of a battery contact on a Canon...
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Paul Howell

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I have a 9 as well along with a 9XI and 800si. The 9000 is still a good camera, you can shoot manual film advance, a film winder or a true motor drive. What I like is the spot shadow and highlight metering modes . What is an issue for me with the 9 is that the viewfinder readout is a bit dim, hard to read in bright desert light then the weight. I use the 9 when shooting wildlife or in bad weather. The 9Xi uses those stupid cards for some advanced functions like bracketing and multi exposure. Has the same top shutter speed as the 9 1/12000 of a second. It is much lighter than the 9, although it lacks the stainless steel body and weather sealing it seem robust. The viewfinder readout is pretty good, I tend to use mine in manual mode. The 800si is my go to day to day shooter. The predicative autofocus works well, the viewfinder readout is bright, light, I have a battery grip for both the 9 and 800si. What the 9 has is the ability to bracket with exposure compensation that are controlled by buttons and switches on the body, no need to deep dive into the menu.
 
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Andreas Thaler

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Speaking of seals:

Unfortunately, the Minolta 9000 didn't come with any, which surprises me, as it was positioned as a professional camera. But even the dedicated amateurs would be happy about it.

My experience described above with the settings acting crazy shows what moisture can do to electronics. In the worst case, there can be a short circuit with fatal consequences for the electronics.

But it's not good for the metal parts either, see the rust under the rotary switch for the exposure metering modes.
 

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I think when the 9000 came out in the mid 1990's people (pro's) were still using cameras like the Canon F1 and the canon, Nikon F2(From all accounts Press in UK didn't trust the F3 electronics) when they were using these two iconic and possibly best pro quality manual focus and manual shutter they, had not even considered the Minolta 9000. There were perfectly happy with changing shutter speed and apperture manually, that Minolta probably didn't even think of automation beyond exposure. It could be because the pro's were used to it and could manage it very well, without the added complexity and possible distrust of automation.
 

Paul Howell

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Although the A7000 and A9000 were the first system AF on the market it was Canon who took over the market. The A9000 AF is good, but no better than the Nikon F4, Canon got AF right. The early Canon AF bodies with all micro motor lens had faster and more positive AF than the gear driven lens of Minolta and Nikon. The EOS 1 coupled with L glass lens became the standard that all others were held to. My thinking is after losing a 100 million dollar patent infringement suit to Honeywell that Minolta just did not have the resources to catch up, by the time of the F5 Canon was dominate. Although not a pro level camera the Pentax FSn had really good AF.
 
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Andreas Thaler

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I let the Sugru harden and smoothed the area with the Dremel and a polishing tip. I finished the work with ultra-fine sandpaper.

Another piece of the handle came off, which I will glue in place.






In the next step, I will treat the entire handle with black spray paint.


If this solution doesn't work, I will remove the entire covering from the handle.

It will then look like this:



Advantage: It is solid plastic that doesn't stick.
 
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Fixed




However, the next cracks are already visible.

I will see if the covering holds.


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Andreas Thaler

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Sticky shutter

Today I tested my 9000 series on the motor drive MD-90.

The cameras work with the motor, but it turns out that on some of them the shutter does not open at 1/4000 of a second.

I put this down to the sticky shutter:



Where sticky contamination (due to a rotten damper on the shutter) is visible on the second shutter curtain, cleaning with acetone helps, but only for a short time.

The shutter can be observed well with the back panel removed and the motor drive attached in H(igh) mode:



The camera then fires at 1/4000 of a second. When viewed against a bright surface, some light should be visible from behind through the shutter.

When used continuously in High mode, you can see that after around 36 shots the shutter no longer opens or only opens irregularly.

The only solution is to remove the shutter and clean it.


See also:

Minolta 9000: Examination of the sticky shutter and discussing solutions

Following these threads on issues with the Minolta 9000 https://www.photrio.com/forum/threads/minolta-maxxum-9000-dissection-and-investigating-the-aperture-issue.208476/ https://www.photrio.com/forum/threads/8-x-minolta-maxxum-9000-and-4-x-minolta-af-lenses-a-sample.210960/ I am starting a...
www.photrio.com

Minolta MD-90, BP-90 and AW-90: Test, troubleshooting contact problems, dissection

Today I achieved my goal of putting together two functional units, each consisting of a Minolta 9000 and a Motor Drive MD-90 with a BP-90 battery holder. It was also an eventful session: One of my six working 9000s failed. I was able to add a working Winder AW-90 to my ensemble and I...
www.photrio.com
 
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Andreas Thaler

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@ogtronix

You have already successfully disassembled a 9000 and removed the damper residue from the shutter. And also removed the aperture control:

Post in thread 'Minolta (Maxxum) 9000: Dissection and investigating the aperture issue'
https://www.photrio.com/forum/threa...gating-the-aperture-issue.208476/post-2850057

If it's just the shutter, how high do you think the chances are that the 9000 will work again afterwards? So the risk of disassembling and reassembling?

I will look at the procedure in the service manual together with your post.

The 9000 cannot be used with the rotting damper in the shutter, cleaning it from the outside won't help here.
 

ogtronix

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I think it wasn't too bad. The risky part is probably desoldering the two flat flex cables from the top PCB on the flanks of the prism. I'm still sorta psyching myself into taking the thing apart again to clean the aperture magnet more thoroughly (and probably finely and very lightly sand the surface to remove the shine) and that's the part I imagine going wrong since one of those flex PCBs was just starting to delaminate. There's also some fiddling to reinstall that one part of the winding mechanism on the bottom, and that one metal part of the frame counter felt like them interlocked metal ring puzzles.

The shutter itself seems potentially risky to open. I had some problems getting the screws out without chewing them a little on one of them, since they're adhered in place and the cheap tipped screwdriver I was using was starting to wear out. I could also imagine a slipped tool or a sneeze dislodging the shutter blades and causing a mess. Or whatever might happen if you accidentally hit the shutter's trigger with the top plate off... I was also concerned with reassembly and not getting that one C shaped leaf on the left pinched during reassembly (I held it in place with some kapton tape on the 2nd shutter).

Y'know when I do open it again, maybe I should put a tiny bit of loctite on them screws so they continue to stay in place. Are regular loctite thread retainers safe around optics?
 
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Andreas Thaler

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When I disassembled the shutter of a 9000 (dissection), I noticed two small springs on the side that came off quickly. Otherwise, I found the structure understandable. But it's better not to touch it.

Maybe it will work to dissolve the damper with acetone, otherwise there are no plastic parts there.

I will start with a test run - like NASA once did on their Apollo missions - I've had enough abandoned 9000s by now. First, practice disassembling.

Were you able to correctly interpret the instructions in the service manual for inserting the mirror box? So which parts should be cocked?
 

ogtronix

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Yeah I found the assembly reasonably straightforwards following the service manual's stuff (124-129 of the pdf). The trickier part was wrangling all the wires. There's a couple on the shutter button side of the camera that got lost in a hole, that grey wire for the AF/MF switch that got loose and under the contacts on the lens release side of the camera, and all the wires to that green DC/DC converter board on the bottom of the camera are a bit annoying to reattach and route correctly so they don't get pinched.

I'm remembering another couple tricky points though. That flex cable for the autofocus motor on the bottom of the camera that's soldered to the DC/DC converter, I imagine it'd be easy to tear that if it got snagged during removal of the mirror box. And it really tries its best to get re-snagged. And a pad of annoying adhesive on the back of the mirror box/ prism that held the thing together as if i'd missed a screw, along with risking tearing the light sealing foil.

Also the service manual suggests alot of the small brass washers around and about are from revisions, so there could be who knows how many loose washers waiting to escape.
 

ogtronix

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Oh yeah I forgot to say also that I put everything in cocked but I'm not sure it matters too much, but would make the levers easier to actuate when testing I suppose.

Also i'd worry about acetone affecting the insulation of the wires, including the enamel windings on the electomagnets, as well as those square rubber things visible in your photos (deeper into the shutter than I went). Even if you just immersed the icky part of the shutter you'd still be exposing the rest to vapours. It's probably best to just open it up and remove the bumpers that way... And possibly even replace them if you can find some rubber or silicone sheet to cut - I feel they were probably there for a reason. I was considering some blobs of silicone sealant but the normal bathroom stuff releases vinegar as it cures, which probably wouldn't be great inside a camera.
 
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Andreas Thaler

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I would try using foam for mirror shock absorbers, which I cut to size, it is self-adhesive.
 
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