Minolta 5400 Mark 1 - ZigZag artefacts

[Archiloque]

Yeah, that's what I noticed, huge variance between units. The 4 5400MK1 that I own all presents differents noise levels and patterns.

 

[scarbantia]

Meanwhile in my futile quest for the perfect scanner, I've received a 185 euros quote for the glass removal of the CCD sensor. I may go ahead with it, I just need to find a way to desolder it from its PCB as Eureca told me the procedure would be a lot riskier with a PCB. So, now, I need to get a desolder pump and hope for the best . I think i'll do it for completion sake.

I know it's a crazy idea, but I'm always thinking about how to cool the sensor. A drop of 5-10C° can reduce the noise. I was thinking of a thin heat pipe or a peltier, but it's probably impossible to put it under the sensor without it moving out of place.
The PCB is screwed to a plate. Does this have a thermal conduction function or is it just a support frame?

If you remove the sensor, can you take some pictures?

 

[dando]

Thank you for the interesting thread!
I am new to scanners, but am in the process of finding the optimal scanner to digitize my family's 35mm negatives.
I recently came across a project which seems relevant, as earlier @scarbantia mentioned (narrowband) trichromatic (RGB) light sources.
Here's a link:

GitHub - jackw01/scanlight: A better light source for scanning color negative film

A better light source for scanning color negative film - jackw01/scanlight

github.com

Maybe someone would find this interesting and useful.

In order not to be completely off-topic, @Archiloque, did you manage to remove the glass of the CCD sensor?

 

[Fish soup]

I own three of these scanners (one stands out with much better noise performance compared to the other two. My guess is that the bulb is in much better shape on this unit).

I've read about this issue before, but hadn't really noticed it in my daily usage. However, after going through this thread, I decided to run some tests on a few very dense color negatives (I don’t usually shoot slides, which might explain why I hadn’t noticed it).

I discovered that I could easily trigger the zig-zag issue in very dense areas on my less capable scanners. When scanning color negatives as linear positives with auto exposure turned OFF, grain dissolver ON, the zig-zag pattern and some banding primarily appeared in the blue channel, with some hints in the green. The red channel remained clear. I found that by using the analog gain in Dimage to elevate the blue and green channels to match the red channel and get them out of the “gutter” on the histogram, most artifacts would vanish. However, this also made the scan times ridiculously long. Plus, this won’t help at all when scanning transparencies. But for color negatives, it mostly solved the zig-zag issue on my scanners. So, it seems that optimizing the signal-to-noise ratio is key.

I also found some information stating that diffusion filters, like the grain dissolver, diffuse light more in the blue spectrum than in the red, so the blue channel is already at a disadvantage by receiving less light.

Additionally, I found that if I let the scanner (and the lamp!) warm up for about 30 minutes and then recalibrated the scanner by pressing ctrl+shift+I, it tended to performed better. So, I suspect that a lot of the issues might stem from worn-out lamps, possibly in tandem with aging capacitors.

@Archiloque,
Your LED swapping experiment was genius! Could you share more specifics on the exact parts you used? I’ve also been curious if simply swapping out the bulb could fix many of the issues. I’ve seen that folks are replacing the bulb in the Multi Pro with new off the shelf parts on the Minolta scanner group on FB, and it seems to work pretty well. Do you know the dimensions of the bulb in the 5400?

 

[koraks]

I discovered that I could easily trigger the zig-zag issue in very dense areas on my less capable scanners.

On a somewhat related note, I noticed something similar yesterday with my old Scan Dual IV. This was when scanning a B&W negative with a fairly dense sky (ca. 1.9logD) with all corrections in the Dimage software turned off/zeroed. When boosting the contrast in the flat sky area, I could bring out the familiar zig-zag pattern. I rescanned the negative with the exposure set to +2 in Dimage, resulting in a perfectly clean scan.

Btw, welcome to Photrio!

 

[Fish soup]

Thanks! I've been a long time occasional lurker since the apug days.

Yes, simply boosting the exposure will do wonders to bury the noise.
But on some of my densest negs it seemed that my worst copy of the 5400 was struggling to boost the blue channel enough relative to the red no matter what.. The histogram in the blue channel looked a bit weird and stretched, and the scan times almost came to a halt. But in the end most of the artifacts were gone. My best copy does not have the same problem with lifting the blue channel. I suspect a brand new bulb would fix this.

Edit: Though the mod @Archiloque did seems very tempting. The turtle like speeds of the 5400mki has always been the Achilles' heel of an otherwise very good scanner. Maybe the best dedicated 35mm scanner ever. Cutting the scan times in half or even more would be a god send.

 

[koraks]

The histogram in the blue channel looked a bit weird and stretched, and the scan times almost came to a halt. But in the end most of the artifacts were gone. My best copy does not have the same problem with lifting the blue channel. I suspect a brand new bulb would fix this.

I follow your analysis and agree that the light source would be the first thing to have a look at given these symptoms.

 

[Archiloque]

Hi guys,
To answer the questions above : no unfortunately, I did not end up sending my sensor to Eureka to have its protection removed. I never dared to unsolder it... I will probably do it when I have more time but I have currently no more time to play with my good old Minolta scanners (I will come back to them eventually, but not before a few months).

The parts for the Led mods were pretty straightforward, just 0.5m of the 5mm natural white led band (24V) available right there on aliexpress and a matching PSU.

 

[Fish soup]

@Archiloque Perfect! I might try that if I feel brave enough.

Do you also happen to remember the dimensions of the original bulb? I saw that you had tried replacing that as well.
And is the exact diameter important, or would a say 3mm tube fit even if the original is 2mm? I'm eager to pursue that route as well. The investment seem rather small, so nothing to lose really.

 

[BMbikerider]

I've been using a Minolta 5400 scanner for a few years now. Despite having both top of the line Coolscans at home (the 5000 and 9000), I still believe the Minolta 5400 Mk1 is my best scanner when it comes to extracting as much information as possible from a 35mm negative. I have scanned numerous photos with all these scanners and while the Coolscan tend to have better colors right out of the box, the Minolta 5400 diffuse lighting really give a more pleasing and forgiving image, especially when you have some imperfections on your negatives. Also, its resolution and grain rendition is unmatched.

It is slow, it is a brick. But I really believe it was the pinnacle in terms of image quality when it comes to advanced user scanners for 35mm.

Anyway, after these praises for a 20 years old scanner nobody asked for, here is my problem.

I noticed in dark areas the presence of zigzag artefacts. No matter what value of multisampling I choose, they're still here. I know that Coolscans tend to suffer from the same illness. I have an old Coolscan 4000 that suffers from it. But this issue has been well documented and investigated by the community, and the culprit identified. It's a simple 30 cents capacitor involved in the Analog Digital conversion that needs to be replaced.

Unfortunately, the 5400 doesn't attract the same interest from users nowadays. Sadly, their only appeal seems to be their lens, hence the sheer number of units sold without it on Ebay. Anyway, I was wondering if anyone had any idea of what capacitor or IC chip could be falty ?
Here are two examples. One in the shadows of a slide. Another in the densest highlights of a negative. Click to enlarge :

View attachment 336889 View attachment 336890

I plan to have all the chemical capacitors replaced at some point but I wondered if anyone had already encoutered this issue and had some clues. Thanks.

I have a Nikon Coolscan V which doesn't get as much use as it used to because I still prefer wet printing, but when I do use it I always use the RAW channel to scan and have no problem with shadow detail. Additionally I also believe the Nikon range have a greater D max that any other scanner of the same era of 4.2 which also helps with shadow details.

 

[brbo]

Additionally I also believe the Nikon range have a greater D max that any other scanner of the same era of 4.2 which also helps with shadow details.

Not true.

And especially not in case of Coolscan V which is a 14bit scanner and doesn't have multisampling.

 

[BMbikerider]

Well the d Max of the Coolscan V is stated in the manual as 4.2 and on a test of the epson D850 the D Max was stated at 3.8 and there is 20 years since the C.S.V. was made so they have not improved it all that much. The Epson v850 gives quite soft images compared to that of the C.S.V.
I have never worried about multisampling and with 14 bit RAW (NEF) can drag an enormous amount of information out of the shadows. It is also pretty good at sorting out highlights too.

I go by results I see, not theoretical assumptions

 

[brbo]

I'm not trying to say that your scanner doesn't give you results that you are very happy with. It obviously does.

I'm just saying that throwing theoretical specifications and untrue information around doesn't help anyone. Coolscans didn't and don't have better Dmax (you probably meant to say Drange, though) than all other scanners, Coolscan RAWs packed into NEF container are the same as any other RAW from any other scanner (basically just TIFFs) and multisampling does provide measurable benefits to the usable Drange of the scanner.