Problem with heavy Vignetting

[analog_input]

Hi everyone,

I’m kinda frustrated since the results I get are ranging from brilliant to super bad. I can’t quite figure out what’s the problem. But I’m sure it’s my fault since all your pictures come out so good!!

Also - NLP is the best!

First some Examples:

^That’s the photo I’m the most unhappy about - because I actually like it. The vignetting is so uneven that I can’t get any better results than that…

^The blue tint on the left.

^It’s subtle here but still there on the bottom.
And at the same time:

^Much better in a Photo taken literally minutes later in the same light.

Most frustrating is the fact that it doesn’t seem so bad at all from time to time:

As I move further away from the negative it seems to get better, but then I get super bad flares:

My scanning setup:
-Sony A7M2
-Canon FD 100 F4 Macro with FD50 extension-ring to reach 1:1 magnification (that’s actually a ultra sharp lens)
-Dörr LT-2020 lighttable (with black tape for no illumination except for the negative)
-Manfrotto Befree GT XPro

My settings are:
-lighttable max power
-stopped down to F16 for less vignetting and sharper images ( )
-ISO 100
-1/5th of a second shutter speed
-I scan mostly at night with no lights on except the light table!

I hope someone can identify my fault!

Greetz

Felix

[Digitizer]

Is there any issue when you take an image without film, just the light source alone? I had a case wherelighting seemed to be even but was not. Taking just the light and adjusting the resulting image to the extreme was revealing!

[nate]

@analog_input

-Sony A7M2

The earlier Sony A7 models do seem to have some “sensor flare” issues… Because it is mirrorless, the sensor is very close to the lens, and seems to cause more flare in extreme circumstances. As I understand it, the newer Sony models have improved this.

I’m not as familiar with the Dörr LT-2020 as some other models, but I may try going for less power on it, and see it that lowers the amount of flare?

@analog_input

-Canon FD 100 F4 Macro with FD50 extension-ring to reach 1:1 magnification (that’s actually a ultra sharp lens)

Have you tried WITHOUT the extension ring? Worth a shot… I’ve seen cases where the extension ring cased some issues with flare… also the extension ring may be preventing Lightroom from recognizing the main lens you used, and applying the proper lens correction profile.

@analog_input

-stopped down to F16 for less vignetting and sharper images ( )

Most lenses reach their peak sharpness around F8… so at F16 you will be gaining depth of field, but the lens won’t be as sharp. It’s worth a try to see if F8 makes it better or worse.

[analog_input]

First of all - THX for your replies!

@Digitizer
You were right! But the light table itself actually delivers really even lighting.
The actual problem was:
The black electrical tape (I used it to block light around the Area of the single negative) was somehow reflecting the light back down in the light table and back up - resulting in uneven lighting!
Removing some of that around the negative solved that problem.

@nate
I tried it without the extension ring and - as mentioned above - with less masking of the light coming from the LT.
-> NO flare and FAR less vignetting!

^Thats the photo after fiddling around - works for me! Grey is always an extreme condition…

^Thats the flares I get when using the lens with the FD50 Extension ring. When I’m at the closest focusing distance (at 1:1) they disappear but the edges will lose their sharpness.

I was hoping to get the highest resolution possible with my A7M2
So then I’ll save some money to get another setup…or live with those 6MP photos.

For general photography on the other Hand:
This lens is incredibly sharp and there’s almost no vignetting even at F4 - I’ll keep it for sure!

@nate
Do you have any recommendations which lens I could use?

Thanks a lot!

[Digitizer]

@analog_input

which lens I could use?

…often, it is a good move to use an original lens and Sony’s FE 90 mm f/2.8 Macro G OSS looks good on dxomark.com…

[MorroW]

I run old Micro-Nikkor 60mm F2.8 for example.
But Sony 90mm is also good.
I hahven’t used yet Sony’s 50mm macro, but it’s on plans

[analog_input]

Well I‘ll borrow both the 90mm and the 50mm original Sony FE lenses and test them.
The 90mm is really expensive, tho…
The 50mm is said to have quite heavy vignetting too, but thats better than the 1:2 max magnification, I think…I like grain!

[MorroW]

Please share later your results/findings

[runswithsizzers]

Are you are talking about the four brownish, bullet-shaped areas in the corners?

Look inside the extension rings from the back (camera) side. Can you see four of anything shiny - screw heads, maybe? If so, you might try to paint the shiny bits with flat black paint.

[Richard1Karash]

You asked what lens? I’ve tried many, on Sony A7 and A6000. Here are some that I like a lot:

• 90 f/2.8 Sony Macro
• 70 f/2.8 Sigma Macro ART (half the price of above, AF, goes to 1x)
• 55 f/2.8 Micro Nikkor AI (manual focus; needs PK-13 tube for 1x)

[Digitizer]

You could also use a medium format lens and reverse mount it to your camera. This should remove vignetting - at least the one caused by the lens.

[Clemens]

I am using the Sigma 70mm Macro, based on Richards recommendation, it’s very sharp.
To get rid of vignetting, you can use Lightrooms Flat Field Correction plugin.

[analog_input]

So I tested a few lenses in the past 2 months.

Among with the testing, I did my daily work with the Canon FD 100 F4 macro - as usual. But with that I could only get to 1:2 magnification. The extension ring was unusable due to heavy vignetting and super bad flares (as mentioned above).
With only 1:2 my 35mm negatives were just around 2800x1900px in size. That’s not enough for me so I decided to finally buy a e-mount lens.
I thought: “I would spend the same amount of money (or even a bit less) for a proper flatbed scanner, but a lens would save me lots of time and will be suited for my normal digital photography as well. - A good investment”.

There were four lenses I wanted to try:

1. Native Sony 90 f/2.8 Macro _______________________________ aprox. 1100€
2. Native Sony 50 f/2.8 Macro _______________________________ aprox. 500€
3. Sigma 105 f/2.8 Macro + Sony LA-EA4 A- to E-Mount adaptor ____ aprox. 600€
4. Sigma 70 f/2.8 Macro (as recommended by @Clemens) ________ aprox. 500€

…, but then there came the Corona lock-down and all the camera stores closed…

I don’t like buying stuff on the internet just to test it and then send it back if I don’t like it.
So what I did was reading a lot of tests and reviews. Also, I made myself a list of features I need in a lens.

• After a short time I found that the 90mm from Sony is just way too expensive.
• The second thought was: “There’s no guarantee that the LA-EA4 adaptor doesn’t produce flares just like the extension ring does.”
• The decision between the Sony 50mm and the Sigma 70mm was pretty easy since I found a sigma used in the online store of a german camera store (I’m German) for 429€.

But I think the Sony 50mm would be just as good of a choice after all!

/
/

The lens arrived yesterday, so I tried it last night.
TLDR - It’s just perfect!
SUPERSUPER sharp - just like @Clemens stated. Stopped down a bit there’s no vignetting at all and the focus-by-wire system is a charm after getting used to. I refocused the Canon FD 100 every couple of shots just because I wasn’t sure if it didn’t slip out of focus simply because of gravitation.

The downside of the Sigma 70mm f/2.8 Macro Art is that I had to change my scanning setup by a bit, because you have to get really really close compared to the Canon FD lens. Maybe a repro stand will make life easier! But after quite a bit of leveling around my solution with my tripod works just fine.
Look for yourself:

Something else is worth mentioning:
The lens is pretty big compared with the Canon FD 100 f/4 Macro, but it’s small compared with the Sony FE 90mm f/2.8 Macro. It also has no image stabilisation - but I don’t need that anyways…

Here’s a size comparison:
Left to Right:
Canon FD 100mm f/4 Macro __ Sigma 70mm f/2.8 Macro Art __Sony FE 28-70 Kit Lens

I rescanned some of my good older negatives for the extra resolution.
Here are the rescans of two photos from the original post:

Overall I hope this thread and my thoughts will help somebody who has similar problems!
Thanks to everyone that has helped me!

[analog_input]

Look down below!

[MorroW]

I will be reassembling customer setup with Sony 50mm and Arca Swiss rail next week, will post pictures.
I think you would prefer that much more compared to standard big repro.

P.S. I saw really bad copy of Sigma 70mm lens so I went with 50mm Sony.

[C.lement]

Nice! Do you have any experience with the 50 f/2.8 sony macro? I was considering it along with the sigma, but 50mm is a better lens for me for just general digital work. As for the nikon, will the tubes cause any flaring problems?

[C.lement]

awesome, Id be interested to see the photos! looking to get the 50mm too

[C.lement]

@Digitizer

ou could also use a medium format lens and reverse mount it to your camera. This should remove vignetting - at least the one caused by the lens.

Do you have any experience with using a medium format lens on full frame? Looking for a lens to scan and I have a medium format macro one, wondering if I could just use that

[Digitizer]

I still have a Mamiya 645 and a set of lenses. I’ve used them on an EOS 5D Mark III with a Fotodiox Adapter with focus confirmation chip, which came off, luckily outside of the camera.

I reverse mounted the 80mm lens, also with extension rings and it worked fine, albeit a bit clunky, also because aperture is fully manual which adds a few steps for each shot. Well, I also have a Canon EF100mm Macro lens which is much easier to use. Maybe it’s an idea worth considering to buy an original macro lens or a set of extension rings instead of spending some effort for a kludge which could make you cave in and buy the macro lens anyway…

Find my current setup here.

[C.lement]

I see, thanks for sharing your setup, very interesting!

As per my other post, I already own a hasselblad 120/4 macro lens with a bunch of extension tubes. I was wondering if it will be viable to buy a adapter to adapt the hasselblad onto my sony a7ii. Im concerned if the adapters and tubes will cause all sorts of problems, and I also have no idea how the magnification will work on when using mf lens on a full frame camera.

Thanks!